LICENSE AGREEMENT

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                                                                   EXHIBIT 10.37

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.

                                LICENSE AGREEMENT

                                    PREAMBLE

     THIS LICENSE AGREEMENT ("Agreement") is entered into as of the 3rd day of
March, 2006 (the "Effective Date") by and between Myogen, Inc., a Delaware
corporation, with its principal place of business at 7575 W. 103rd Avenue,
Westminster, CO 80021-5426 ("Myogen") and GLAXO GROUP LIMITED, a private limited
company incorporated in England and Wales, having its registered office at Glaxo
Wellcome House, Berkeley Avenue, Greenford, Middlesex, England UB6 0NN ("GSK").
Myogen and GSK are sometimes collectively referred to herein as the "Parties"
and separately as a "Party."

     WHEREAS, Myogen is the licensee of certain rights in the Abbott
Intellectual Property (as hereinafter defined), and has the right to grant
certain sublicenses thereunder, relating to Compound (as hereinafter defined)
and/or Product (as hereinafter defined) in the Field (as hereinafter defined);
and

     WHEREAS, GSK desires to obtain an exclusive sublicense from Myogen under
the aforesaid Abbott Intellectual Property to make, have made, use, sell, offer
for sale and import Compound and Product in the Field in the GSK Territory (as
hereinafter defined), and Myogen is willing to grant to GSK such sublicense, in
accordance with the terms and conditions of this Agreement; and

     WHEREAS, Myogen owns or otherwise controls the Myogen Intellectual Property
(as hereinafter defined), and has the right to grant certain licenses
thereunder, relating to Compound and/or Product in the Field; and

     WHEREAS, GSK desires to obtain an exclusive license from Myogen under the
aforesaid Myogen Intellectual Property to make, have made, use, sell, offer for
sale and import Compound and Product in the Field in the GSK Territory, and
Myogen is willing to grant to GSK such license, in accordance with the terms and
conditions of this Agreement.

     NOW, THEREFORE, in consideration of the mutual covenants and agreements set
forth herein and other good and valuable consideration, the receipt and legal
sufficiency of which are hereby mutually acknowledged, Myogen and GSK hereby
agree as follows:

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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                                     ARTICLE I

                                   DEFINITIONS

     Section 1.1 Definitions. As used herein, the following capitalized terms
will have the meanings set forth below when used in this Agreement, and all
terms defined in the singular will have the same meanings when used in the
plural (and vice versa), unless otherwise specified.

     "Abbott" means Abbott Deutschland Holding GmbH, a German legal entity, with
its principal office at Max Planck Ring 2, 65205 Wiesbaden, Germany.

     "Abbott Agreement" means the License Agreement by and between Abbott and
Myogen, dated as of October 8, 2001, and any amendments thereto. A complete copy
of the Abbott Agreement as of the Effective Date is attached hereto as Exhibit
A.

     "Abbott Intellectual Property" means the Abbott Know-How and Abbott Patent
Rights, collectively.

     "Abbott Know-How" means Know-How that is Controlled by Abbott as of the
effective date of the Abbott Agreement and which has been licensed to Myogen in
accordance with the terms and conditions of the Abbott Agreement.

     "Abbott Patent Rights" means the Patent Rights defined in Section 1.16 of
the Abbott Agreement. Myogen has provided to GSK a list of Abbott Patent Rights
current as of the Effective Date. A list of issued patents and pending PCT
applications included within the Abbott Patent Rights in the GSK Territory is
attached hereto as Exhibit B, and Myogen will update such Exhibit promptly upon
GSK's reasonable written request, which request will not be made by GSK more
than twice in any Calendar Year during the Term.

     An "Affiliate" of a Party or Person means any Person, whether de jure or de
facto, that directly or indirectly, controls, is controlled by, or is under
common control with such Party or Person, as applicable. Solely as used in this
definition, "control" means (a) direct or indirect ownership of more than fifty
percent (50%) of the equity (or such lesser percentage which is the maximum
allowed to be owned by a foreign corporation in a particular jurisdiction)
having the power to vote on or direct the affairs of such Party or Person, as
applicable, or (b) the possession, directly or indirectly, of the power to
direct or cause the direction of the policies and management of such Party or
Person, as applicable, whether by the ownership of stock, by contract, or
otherwise.

     "Agreement" will have the meaning set forth in the preamble.

     "Applicable Law" means all applicable provisions of any and all
supra-national, federal, national, state, provincial, and local statutes, laws,
rules, regulations, administrative codes, ordinances, decrees, orders,
decisions, injunctions, awards judgments, permits and licenses of or from
governmental authorities relating to or governing the use or regulation of the
subject item.

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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     "Assumption of Responsibility Notice" will have the meaning set forth in
Section 6.1.

     "Auditor" will have the meaning set forth in Section 9.3(e).

     "Business Day" means any day other than a day which is a Saturday, a Sunday
or any day banks are authorized or required to be closed in the United States or
in the United Kingdom.

     "Calendar Quarter" means each of the consecutive three (3) month periods
ending March 31, June 30, September 30, and December 31; provided, however, that
the first (1st) Calendar Quarter under this Agreement will be the period
beginning on the Effective Date and ending on the end of the Calendar Quarter in
which the Effective Date is encompassed.

     "Calendar Year" means, for the first Calendar Year, the period beginning on
the Effective Date and ending December 31, 2006, and for each Calendar Year
thereafter, each successive period beginning on January 1 and ending twelve (12)
consecutive calendar months later on December 31; provided, however, that the
last Calendar Year of the Term will be the period beginning on January 1 and
ending on the effective date of expiration or termination of the Term.

     "Commercially Reasonable Efforts" means efforts and resources normally used
by a similarly situated pharmaceutical company in the GSK Territory or Myogen
Territory, as applicable, in the exercise of its reasonable business discretion
relating to a prescription pharmaceutical product owned by it or to which it has
exclusive rights, which is of similar market potential at a similar stage in its
development or product life, taking into account issues of patent coverage,
safety and efficacy, product profile, the competitiveness of the marketplace,
the proprietary position of the compound or product, the regulatory structure
involved, the profitability of the applicable products (including, without
limitation, pricing and reimbursement status achieved), and other relevant
factors, including without limitation technical, legal, scientific, and/or
medical factors, and provided that all such actions are consistent in all
material respects with the Development Plan or Global Marketing Plan, as the
case may be.

     "Commercialization" or "Commercialize" means activities directed to
obtaining pricing and reimbursement approvals, marketing, promoting,
distributing, using, importing or selling the Product in the Field.
Commercialization will not include any activities related to Development or
Manufacturing.

     "Common Technical Document" means a harmonized structure and format for new
drug product applications developed by ICH to be used by the Parties, as
appropriate and subject to clinical data availability and Applicable Law in a
country, in connection with Regulatory Approval Applications for Product in the
European Union, Japan, Canada and the United States.

     "Compound" will have the meaning set forth in Section 1.5 of the Abbott
Agreement.

     "Confidential Information" means any and all information disclosed to or
obtained by Recipient pursuant to or in connection with the negotiation,
execution, delivery and performance of this Agreement or the consummation of the
transactions contemplated hereby and any and all information regarding, related
to, or associated with any or all elements of this Agreement,

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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including the Development, Manufacture and/or Commercialization of Product in
the Field or any aspect thereof, or each Party's operations that is disclosed by
the Disclosing Party to the Recipient; provided, however, that Confidential
Information will not include information which: (i) at the time of disclosure is
in the public domain; (ii) after disclosure becomes part of the public domain,
except through breach of this Agreement; (iii) the Recipient can demonstrate by
reasonable proof was in its possession prior to the time of disclosure by the
Disclosing Party hereunder, and was not acquired directly or indirectly from the
Disclosing Party; (iv) the Recipient can demonstrate by reasonable proof was
developed by or on behalf of Recipient independent of and without reference to
the Disclosing Party's Confidential Information; or (v) becomes available to
Recipient from a Third Party who did not acquire such information directly or
indirectly from the Disclosing Party and who is not otherwise prohibited from
disclosing such information.

     "Confidentiality Agreement" will have the meaning set forth in Section
13.1(h).

     "Control" means, with respect to the subject item, the ability and
authority of a Party or its Affiliate, whether arising by ownership, possession
or pursuant to a license or sublicense, to grant licenses or sublicenses to the
other Party under or to the subject item as specified in this Agreement, without
breaching the terms of any agreement with any Third Party and/or its Affiliates.

     "Cure Period" will have the meaning set forth in Section 11.2.

     "Development" or "Develop" means non-clinical and clinical research and
drug development activities related to obtaining and maintaining Regulatory
Approval (excluding pricing and reimbursement approvals) for Product in the
Field, including test method development and stability testing, process
development, formulation development, delivery system development, quality
assurance and quality control development for clinical supplies, statistical
analysis, clinical studies (including pre- and post-approval studies),
regulatory affairs, and Regulatory Approval (excluding regulatory activities
directed to obtaining pricing and reimbursement approvals) and clinical study
regulatory activities (excluding regulatory activities directed to obtaining
pricing and reimbursement approvals).

     "Development Information" means any and all information generated by a
Party (or a Party's Affiliates or any Third Party on behalf of a Party (i.e.,
including, without limitation, suppliers of starting materials, excipients and
packaging)) in the Development of Compound and/or Product as provided in this
Agreement, including, without limitation, information relating to chemistry
manufacturing and control (CMC), protocols, analysis plans, annotated case
report forms per study, analysis datasets, programs, raw data and other relevant
documentation used for the study reporting efforts and minutes from clinical
advisory boards and investigator meetings.

     "Development Plan" means the plan for Development of Product in the Field
in the United States, Canada and Major European Market Countries, which will
include, without limitation, the development, operating guidelines and estimated
filing dates, guidelines for filing Regulatory Approval, any preclinical and
clinical studies to be conducted (including, without limitation, [..**..], each
of which the Parties expect to be completed by Myogen according to the

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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timelines set forth in the Development Plan.

     "Disclosing Party" will have the meaning set forth in Section 13.1(a).

     "Dispute" will have the meaning set forth in Section 14.1.

     "Dispute Notice" will have the meaning set forth in Section 14.1 hereof.

     "Distributor" means a Third Party engaged by a Party or its Affiliates in a
country in the GSK Territory or Myogen Territory, as applicable, to
Commercialize Compound and/or Product in such country, who is not a Sublicensee
or Wholesaler.

     "Effective Date" will have the meaning set forth in the Preamble.

     "EMEA" means the European Medicines Agency of the European Union, or any
successor agency thereto.

     "European Commission" means the European Community authority that has legal
authority to grant marketing authorizations approvals for pharmaceutical
products on an European Economic Area wide basis following scientific evaluation
and recommendation from the EMEA or other applicable Regulatory Authorities.

     "European Critical Care Business Unit" means the business unit within GSK's
European pharmaceutical business unit that is focused on acute cardiology, the
hospital market and GSK's critical care portfolio in Europe.

     "European Economic Area" means those countries forming part of the European
Economic Area at any time during the Term, including, without limitation, those
countries in the European Union. The term "European Union" as used herein and in
the definition of "EMEA" means the countries forming part of the European Union
at any time during the Term.

     "FDA" means the United States Food and Drug Administration or any successor
agency thereto.

     "Field" means any and all therapeutic uses of Compound and/or Product in
humans for the prevention, palliation or treatment of PAH and related etiologies
as defined by the World Health Organization (WHO) clinical classification of
pulmonary hypertension (Venice 2003), a copy of which is attached hereto as
Exhibit C, but excluding any non-therapeutic or non-human use (which
non-therapeutic or non-human use shall include, but not be limited to, imaging,
diagnostics, veterinary medicine, etc.).

     "First Commercial Sale" means the date of the first commercial sale of a
Product in the Field in a country in the Territory or in the GSK Territory or
Myogen Territory, as applicable, in accordance with the terms of this Agreement,
by a Party and/or its Affiliates or permitted Sublicensees to distributors,
wholesalers or other customers in a quantity sufficient for the distribution of
such Product to pharmacies or other commercial distribution channels for sale in

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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the Field in such country or GSK Territory or Myogen Territory, as applicable.
Sales of Product for compassionate use, named patient use, clinical trial
purposes or other similar uses will not constitute a First Commercial Sale.

     "Force Majeure Event" will have the meaning set forth in Section 15.4(g).

     "Generic Equivalent" means, with respect to a particular Product
Commercialized by GSK, its Affiliates or sublicensees in a given country in the
GSK Territory, a pharmaceutical composition approved by Regulatory Authorities
to be sold by a Third Party in such country, which pharmaceutical composition
contains the Compound as an active ingredient and is bioequivalent to such
Product with respect to pharmacokinetic properties. For the avoidance of doubt,
the Generic Equivalent of a particular Product Commercialized by GSK, its
Affiliates or sublicensees in a given county in the GSK Territory, may or may
not be in the same Presentation as such Product.

     "Global Brand Team" will have the meaning set forth in Section 3.3(a).

     "Global Marketing Plan" means the plan for the pre-launch, launch,
post-launch and ongoing Commercialization activities for the Product in the
Field in the Territory.

     "Good Clinical Practice" means the current good clinical practice
applicable to the clinical Development of the Product in the Field under
Applicable Law, to the extent such standards are not less stringent than the
U.S. current good clinical practice, including the guidelines of the ICH.

     "Good Laboratory Practice" means the current good laboratory practice
applicable to the Development of the Product in the Field under Applicable Law,
to the extent such standards are not less stringent than the U.S. current good
laboratory practice, including 21 C.F.R. Part 58.

     "GSK" will have the meaning set forth in the Preamble.

     "GSK Indemnitees" will have the meaning set forth in Section 14.3.

     "GSK Inventions" will have the meaning set forth in Section 10.2.

     "GSK Know-How" means, solely to the extent necessary or useful for the
purposes of Development, Manufacture and/or Commercialization of Compound and/or
Product, all Know-How Controlled by GSK, its Affiliate or a Third Party on
behalf of GSK or its Affiliate at any time during the Term, excluding any Abbott
Know-How or Myogen Know-How.

     "GSK Intellectual Property" means GSK Know-How and GSK Patent Rights,
collectively.

     "GSK Marks" will have the meaning set forth in Section 5.2(d).

     "GSK Patent Rights" means Patent Rights, including the interest of GSK
and/or its

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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Affiliates in Joint Inventions, Controlled by GSK and/or its Affiliates on the
Effective Date or at any time during the Term, excluding the Abbott Patent
Rights and the Myogen Patent Rights.

     "GSK Publication" will have the meaning set forth in Section 13.3(b).

     "GSK Sponsored New Development Activity" will have the meaning set forth in
Section 4.3(d).

     "GSK Territory" means all countries and territories of the world that are
not included in the Myogen Territory.

     "ICH" mean International Committee on Harmonization developed through a
collaboration between the FDA and regulatory agencies in the European Union and
Japan to harmonize regulatory requirements to produce marketing applications
acceptable to the countries of the European Union, Japan and the United States.

     "Indemnitee" will have the meaning set forth in Section 14.4.

     "Indemnitor" will have the meaning set forth in Section 14.4.

     "Initial Royalty" will have the meaning set forth in Section 9.2(a)(i).

     "Joint Inventions" will have the meaning set forth in Section 10.2.

     "JNDA" means a Japanese New Drug Application, which is filed with the MHLW
in order to gain the MHLW's approval to Commercialize a pharmaceutical product
in Japan for the indications set forth in the Japanese New Drug Application.

     "Joint New Development Activity" will have the meaning set forth in Section
4.3(b).

     "Joint Project Team" will have the meaning set forth in Section 3.2(a).

     "Joint Steering Committee" will have the meaning set forth in Section
3.1(a).

     "Know-How" means any proprietary technology, information, methods of use,
processes, techniques, ideas or inventions (excluding any inventions disclosed
in any patent or patent application) which are directly related to or used in
connection with the Compound and/or Product, including any trade secrets and any
other technical information relating to Development, Manufacture and/or
Commercialization of the Compound and/or Product, excluding any Patent Rights.

     "Losses" will have the meaning set forth in Section 14.2.

     "MAA" means a Marketing Authorization Application, which is filed with the
EMEA for review and recommendation to the European Commission to approve such
Marketing Authorization Application for the Commercializing of a pharmaceutical
product in the European

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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Economic Area for the indications set forth in the Marketing Authorization
Application.

     "Major Country" means the following countries: [..**..] Australia, [..**..]
Canada, [..**..] Japan, [..**..].

     "Major European Market Countries" means the following countries: France,
Germany, Italy, Spain and the United Kingdom.

     Manufacturing" or "Manufacture" means all the activities relating to
production of Compound and/or Product, including without limitation, purchasing
raw materials, quality control and assurance, filling, finishing, labeling,
packaging, qualified person release, holding, shipping and storage and the tests
and analyses conducted in connection therewith. Manufacturing excludes
activities relating to Development or Commercialization.

     "MHLW" means the Japanese Ministry of Health, Labour and Welfare or any
successor agency thereto.

     "Milestone Payment" will have the meaning set forth in Section 9.1(a).

     "Milestones" will have the meaning set forth in Section 9.1(a).

     "Myogen" will have the meaning set forth in the Preamble.

     "Myogen Know-How" means, solely to the extent necessary or useful for
purposes of Development, Manufacture and/or Commercialization of Compound and/or
Product in the Field, any Know-How that is Controlled by Myogen or its
Affiliates or a Third Party on behalf of Myogen or its Affiliate on the
Effective Date or at any time during the Term, including, without limitation,
Development Information but excluding any Abbott Know-How and GSK Know-How.

     "Myogen Indemnitees" will have the meaning set forth in Section 14.2.

     "Myogen Intellectual Property" means Myogen Know-How and Myogen Patent
Rights, collectively.

     "Myogen Inventions" will have the meaning set forth in Section 10.2.

     "Myogen Marks" will have the meaning set forth in Section 5.3(d).

     "Myogen Patent Rights" means Patent Rights, including the interest of
Myogen and/or its Affiliates in Joint Inventions, Controlled by Myogen and/or
its Affiliates on the Effective Date or at any time during the Term, excluding
the Abbott Patent Rights and GSK Patent Rights. A list of issued patents and PCT
applications within the Myogen Patent Rights is attached hereto as Exhibit D,
and Myogen will update such Exhibit at least once each Calendar Year during the
Term, or promptly after GSK's reasonable written request, which request will not
be made by GSK more than twice in any Calendar Year during the Term.

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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     "Myogen Publication" will have the meaning set forth in Section 13.3(a).

     "Myogen Sponsored New Development Activity" will have the meaning set forth
in Section 4.3(c).

     "Myogen Territory" means the United States, and any other country in which
this Agreement is terminated pursuant to Section 6.2, Section 6.5, Section 11.4
or Section 11.7.

     "Myogen Trademarks" means the trademarks set forth on Exhibit E, attached
hereto and incorporated herein, and Myogen will update such Exhibit at least
once each Calendar Year during the Term, or promptly after GSK's reasonable
written request, which request will not be made by GSK more than twice in any
Calendar Year during the Term.

     "NDA" means a New Drug Application, which is filed with the FDA in order to
gain the FDA's approval to Commercialize a pharmaceutical product in the United
States for the indications set forth in the New Drug Application.

     "New Development Activity" will have the meaning set forth in Section
4.3(a).

     "Net Sales" means the gross sales of Compound and/or Product by GSK, its
Affiliates or Sublicensees to Third Parties (including, but not limited to,
pharmaceutical wholesalers, pharmacies, hospitals or dispensing physicians), in
arm's length transactions for which revenue is actually received by GSK, its
Affiliates, Sublicensees, less any of the following charges or expenses that are
incurred in connection with such gross sales:

          (a) discounts, including cash discounts, customary trade allowances or
rebates actually taken, governmental rebates, chargebacks, commissions, and
group purchasing management fees for formulary access;

           (b) credits or allowances given or made for rejection, recall or
return of previously sold Product actually taken;

          (c) any tax or governmental charge, duty or assessment (including any
tax such as a value added or similar tax or government charge) levied on the
sale, transportation or delivery of Product when included on the invoice or
other written document between the parties as payable by the purchaser and
collectable by GSK, its Affiliate or Sublicensee; and

          (d) freight, postage, transportation, insurance and duties on shipment
of Product when included on the invoice or other written document between the
parties as payable by the purchaser and collectable by GSK, its Affiliates or
Sublicensees.

Any sales of Compound and/or Product between GSK, its Affiliates and its or
their Sublicensees, for resale, will be excluded from the computation of Net
Sales; provided, however, that the revenue received from the subsequent sale of
such Compound and/or Product by GSK, its Affiliates and its or their Sublicenses
will be included within Net Sales.

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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     "New Field" will have the meaning set forth in Section 2.3(a).

     "New Field License Agreement" will have the meaning set forth in Section
2.3(d).

     "PAH" means pulmonary arterial hypertension.

     "Party" or "Parties" will have the meaning set forth in the Preamble.

     "Patent Prosecution" means, with respect to a Patent Right, (i) preparing,
filing, prosecuting, maintaining, extending and listing, including reissue and
reexamination of, such Patent Right (including reissue, continuing, divisional
and substitute applications and any foreign counterparts thereof) and (ii)
managing any interference or opposition proceedings relating to the foregoing.

     "Patent Rights" means all patents and patent applications including
continuations, continuations-in-part, divisions, patents of addition, patents
issuing from reissue, re-examination, renewal or extension proceedings, utility
models, all Supplemental Protection Certificates and any foreign counterparts
thereof, including PCTs existing as of the Effective Date and/or during the
Term, that generally or specifically claim or cover the making, having made,
use, sale, offering for sale and import of Compound and/or Product in the Field
in the Territory.

     "Person" means any individual, corporation, partnership, firm, association,
joint venture, joint stock company, trust or other entity, or any government or
regulatory administrative or political subdivision or agency, department or
instrumentality thereof.

     "Presentation" means the method of administration of a pharmaceutical
substance into the human body, including solid oral (including tablets,
capsules, gelcaps and caplets), other oral (including suspension and solution),
parenteral (including transdermal, intramuscular, subcutaneous and intravenous),
suppository, inhaled or intranasal.

     "Product" means any pharmaceutical composition containing the Compound,
whether or not as the sole active ingredient, and regardless of formulation,
dosage, or form.

     "Recipient" will have the meaning set forth in Section 13.1(a).

     "Reduced Royalty" will have the meaning set forth in Section 9.2(b)(i).

     "Regulatory Approval" means an approval, license, registration, and/or
authorization necessary for the Development, Manufacture and/or
Commercialization of a prescription pharmaceutical product in the Territory,
including, without limitation, the Shonin in Japan, but not including any
approvals for pricing and/or reimbursement.

     "Regulatory Approval Applications" means an application for obtaining a
Regulatory Approval, together with all documents, data, and information included
with such application.

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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     "Regulatory Authority" means any or all national, supranational, regional,
state, or local regulatory agency, department bureau, commission, council, or
other government entity involved in the granting of Regulatory Approval for a
pharmaceutical product in the Territory.

     "Right of Negotiation" will have the meaning set forth in Section 2.3(a).

     "Right of Negotiation Notice" will have the meaning set forth in Section
2.3(b).

     "Right of Negotiation Period" will have the meaning set forth in Section
2.3(d).

     "Royalty" or "Royalties" means the Initial Royalty and the Reduced Royalty,
collectively.

     "Sublicensee" means a Third Party to whom a Party or its Affiliate
sublicenses or otherwise transfers its right to Develop, Manufacture and/or
Commercialize Compound and/or Product in a country in the GSK Territory or
Myogen Territory, as applicable in accordance with the terms of this Agreement,
and in consideration for such transfer of rights, such Third Party pays such
Party or Affiliate a percentage of, or profit share on, such Third Party's sales
of Compound and/or Product in such country.

     "Supply Agreement" will have the meaning set forth in Section 7.1(g).

     "Term" will have the meaning set forth in Section 11.1.

     "Territory" means the GSK Territory and Myogen Territory, collectively.

     "Third Party" means any Person other than the Parties or their respective
Affiliates.

     "Third Party Payments" will have the meaning set forth in Section 9.2(c).

     "United States" or "U.S." means the fifty (50) states of the United States
of America, the District of Columbia, Puerto Rico and the territories and
possessions of the United States.

     "Wholesaler" means a Third Party engaged by a Party or its Affiliates in a
country in the GSK Territory or Myogen Territory, as applicable under the terms
of this Agreement, whose function is solely to re-sell or distribute and not in
any way promote Product purchased from such Party to other Third Party
purchasers.

     Section 1.2 Clarification. The word "including" or any variation thereof
means "including without limitation" and the word "including" or any variation
thereof will not be construed to limit any general statement which it follows to
the specific or similar items or matters immediately following it. The word
"annual" means each period during the Term from January until December, pro
rated as necessary. The phrase "pricing and/or reimbursement approval
commercially acceptable to GSK" or similar phrases used in this Agreement shall
mean pricing and/or reimbursement approval, as applicable, in the subject
country in the GSK Territory which is commercially acceptable to GSK, as
determined by GSK in its sole discretion,

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
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EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
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provided that any such pricing and/or reimbursement approval shall be deemed to
be commercially acceptable to GSK if GSK, any of its Affiliates, or any of its
Sublicensees achieves the First Commercial Sale of the Product in such country.

                                    ARTICLE II

                                 LICENSE GRANTS

     Section 2.1 Grants to GSK Under Abbott and Myogen Intellectual Property.

          (a) License in GSK Territory.

               (i) Abbott Intellectual Property. Subject to the terms and
conditions of this Agreement and the Abbott Agreement, including Abbott's
internal research license as set forth in section 3.2 of the Abbott Agreement,
Myogen hereby grants to GSK an exclusive sublicense, with the right to grant
further sublicenses as provided in Section 2.2, under the Abbott Intellectual
Property to make, have made, use, sell, offer for sale and import Compound and
Product in the Field in the GSK Territory.

               (ii) Myogen Intellectual Property. Subject to the terms and
conditions of this Agreement, Myogen hereby grants to GSK an exclusive license,
with the right to grant sublicenses as provided in Section 2.2, under the Myogen
Intellectual Property to make, have made, use, sell, offer for sale and import
Compound and Product in the Field in the GSK Territory in order for GSK to
Develop, Manufacture and Commercialize Compound and Product in accordance with
the terms and conditions of this Agreement.

               (iii) Notwithstanding the foregoing or any other provision
contained in this Agreement, Myogen shall retain the right, with the right to
grant further sublicenses upon obtaining the prior written consent of GSK, which
consent will not be unreasonably withheld, under the Abbott Intellectual
Property and the Myogen Intellectual Property, to make, have made and import
Compound, and make and have made Product, in each case, in the GSK Territory for
the sole purpose of exporting such Compound and/or Product from the GSK
Territory for Development, Manufacture and Commercialization of such Compound
and Product in the Myogen Territory. For the avoidance of doubt, Myogen will
have no right to use, sell and offer for sale Compound, or use, sell, offer for
sale and import Product, in each case in the Field in the GSK Territory (as such
term is defined from time-to-time).

          (b) License in Myogen Territory.

               (i) Abbott Intellectual Property. Subject to the terms and
conditions of this Agreement and the Abbott Agreement, Myogen hereby grants to
GSK a non-exclusive sublicense, with the right to grant further sublicenses as
provided in Section 2.2, under the Abbott Intellectual Property, to make, have
made and import Compound and to make and have made Product, in each case in the
Field in the Myogen Territory for the sole purpose of exporting such Compound
and/or Product from the Myogen Territory for Development, Manufacture and

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
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Commercialization of such Compound and Product in the Field in the GSK
Territory. For the avoidance of doubt, GSK shall have no right to use, sell,
offer for sale or import Compound or Product in the Myogen Territory.

               (ii) Myogen Intellectual Property. Subject to the terms and
conditions of this Agreement, Myogen hereby grants to GSK a non-exclusive
license, with the right to grant sublicenses as provided in Section 2.2, under
the Myogen Intellectual Property, to make, have made and import Compound and
make and have made Product, in each case in the Field in the Myogen Territory
for the sole purpose of exporting such Compound and/or Product from the Myogen
Territory for Development, Manufacture and Commercialization of such Compound
and Product in the Field in the GSK Territory.

     Section 2.2 GSK's Right to Grant Sublicenses.

          (a) GSK will have the right to sublicense any or all of its rights
under the Abbott Intellectual Property and Myogen Intellectual Property as
provided in Section 2.1(a) and (b) to its Affiliates, without the consent of
Myogen.

          (b) GSK will have the right to sublicense its rights under the Abbott
Intellectual Property and Myogen Intellectual Property as provided in Section
2.1(a) and (b) to Third Parties to make, have made and import Compound and/or
Product in the Field in the Myogen Territory, for the sole purpose of exporting
such Compound and/or Product from the Myogen Territory for Development,
Manufacture and Commercialization of such Compound and Product in the GSK
Territory in each case upon providing prior written notice to Myogen. If Myogen
does not object to the sublicense by GSK of its rights as provided in this
Section 2.2(b), or if Myogen does not provide any response to GSK, in each case
within [..**..] Business Days after receiving written notice thereof from GSK,
GSK will be free to sublicense its rights as set forth in this Section 2.2(b).
If Myogen objects to the sublicense by GSK of its rights as provided in this
Section 2.2(b) within [..**..] Business Days after receiving written notice
thereof from GSK, GSK will afford Myogen with a reasonable opportunity to meet
and discuss with GSK Myogen's objection to such sublicense, which objection GSK
will consider in good faith but to which GSK will have no obligation to comply.

          (c) GSK will have the right to sublicense any or all of its other
rights, beyond those set forth in Section 2.2(b) above, under the Abbott
Intellectual Property and Myogen Intellectual Property as provided in Sections
2.1(a) as follows:

               (i) to any Third Party who GSK may engage to provide services to
or on behalf of GSK in the GSK Territory relating to this Agreement (including a
Clinical Research Organization (CRO)), except as otherwise provided in this
Section 2.2(c), without the consent of Myogen;

                (ii) to any Third Party who GSK may engage as a Wholesaler in the
GSK Territory, without the consent of Myogen;

               (iii) to any Third Party who GSK may engage as a Distributor of

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Product in a Major European Market Country(ies) or Major Country(ies), with the
prior written consent of Myogen which consent may be withheld for any reason in
Myogen's sole discretion;

               (iv) to any Third Party who GSK may engage as a Distributor of
Product in a country or countries other than a Major European Market Country or
Major Country, without the consent of Myogen; and

               (v) to any Sublicensee with the prior written consent of Myogen,
which consent may be withheld for any reason in Myogen's sole discretion.

Any agreement entered into by GSK pursuant to this Section 2.2(c) will
automatically terminate as to Product, without any action by GSK or such Third
Party or Sublicensee, upon the termination of this Agreement or the Abbott
Agreement.

          (d) GSK shall remain responsible for any breach by a Sublicensee of
the terms of this Agreement or the applicable sublicense agreement. Any
agreement entered into by GSK with a Third Party pursuant to Section 2.2(c)
shall be in writing and shall include provisions acknowledging that such
agreement is subject to the license granted to Myogen under the Abbott Agreement
and to the license granted to GSK under this Agreement, and with respect to
agreements entered into pursuant to Section 2.2(c)(v), that each Sublicensee
shall make reports and keep and maintain records of sales to at least the same
extent required under this Agreement and the Abbott Agreement, allowing Myogen
and Abbott the same access and audit rights permitted under this Agreement and
the Abbott Agreement. GSK shall provide Myogen with a copy of each agreement
entered into by GSK pursuant to Section 2.2(c)(iii) or (v), which copy Myogen
may provide to Abbott in accordance with the last sentence in Section 4.7 of the
Abbott Agreement. Myogen will designate such information as the Confidential
Information (as defined in Section 1.6 of the Abbott Agreement) of Myogen and
notify Abbott in writing of its obligation to maintain the confidentiality of
such agreement in accordance with the terms and conditions of Section 7 of the
Abbott Agreement. Notwithstanding the foregoing, this Section 2.2(d) will not
apply to, and GSK will have no obligations under this Section 2.2(d) with
respect to, to any agreements with any Third Party covered by Section 2.2(c)(iv)
above.

     Section 2.3 Right of Negotiation for Rights Outside of the Field.

          (a) Each time during the Term that Myogen, on its own or through any
of its Affiliates or any Third Party, decides to make, have made, use, sell,
offer for sale and/or import Compound and/or Product for a therapeutic use
outside of the Field in the GSK Territory (each therapeutic use referred to as a
"New Field"), Myogen will provide prior written notice to GSK and thereby grant
to GSK an exclusive option to negotiate with Myogen for an exclusive license
under the Abbott Intellectual Property and Myogen Intellectual Property to make,
have made, use, sell, offer for sale and import Compound and Product in such New
Field (each such notice referred to as a "Right of Negotiation").

          (b) GSK must exercise a Right of Negotiation by providing written
notice to Myogen (each such notice referred to as a "Right of Negotiation
Notice") within [..**..] calendar days after receiving written notice from
Myogen as provided in Section 2.3(a) of such Right of

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
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Negotiation.

          (c) If GSK does not submit a Right of Negotiation Notice to Myogen as
provided in Section 2.3(b) prior to the expiration of the [..**..] calendar day
period referenced in Section 2.3(b), the corresponding Right of Negotiation will
immediately terminate at 12:01 a.m. Eastern Standard Time on the calendar day
that is immediately after last calendar day of such [..**..] calendar day period
and Myogen will have no further obligation to GSK with respect to such Right of
Negotiation; provided, however, that in Developing, Manufacturing and/or
Commercializing Compound and/or Product in such New Field in the GSK Territory
during the Term, Myogen covenants and agrees that it will not, and will cause
its Affiliates and any Third Party not to, knowingly, materially and adversely
affect GSK's right and ability to Develop, Manufacture and Commercialize Product
in the Field in the GSK Territory.

          (d) If GSK exercises a Right of Negotiation by providing a Right of
Negotiation Notice as provided in Section 2.3(b), the Parties will in good faith
negotiate during the Right of Negotiation Period a license agreement pursuant to
which GSK would obtain an exclusive license under the Abbott Intellectual
Property and Myogen Intellectual Property to make, have made, use, sell, offer
for sale and import Compound and Product in the New Field in the GSK Territory
(the "New Field License Agreement"). The "Right of Negotiation Period" will be
the period that commences on the date on which GSK provides Myogen with a Right
of Negotiation Notice as provided in Section 2.3(b) (for the purposes of this
Section 2.3(d) only, the "commencement date") and expires at 12:01 a.m. Eastern
Standard Time on the day immediately following the [..**..] day after the
commencement date. Each such Right of Negotiation Period may be extended upon
the mutual written agreement of the Parties prior to the expiration thereof as
provided in Section 2.3(e) or earlier terminated by the termination of this
Agreement. Notwithstanding the foregoing, GSK will have the right, at any time
and for any reason during a Right of Negotiation Period, to terminate in writing
such Right of Negotiation Period which would terminate the corresponding Right
of Negotiation.

          (e) In the event the Parties have not executed the New Field License
Agreement during the Right of Negotiation Period, after starting to negotiate
the terms and conditions thereof in good faith: (i) the Parties may, upon the
Parties' mutual written agreement prior to the expiration of such Right of
Negotiation Period, extend such Right of Negotiation Period for successive
additional periods of [..**..] Business Days; or (ii) if not extended by the
Parties as provided in (i), such Right of Negotiation Period will expire as
provided in Section 2.3(d) and Myogen will have no further obligation to GSK
with respect to such Right of Negotiation or Compound or Product in such New
Field; provided, however, that in Developing, Manufacturing and/or
Commercializing Compound and/or Product in such New Field in the GSK Territory
during the Term, Myogen covenants and agrees it will not, and will cause its
Affiliates and any Third Party not to, knowingly, materially and adversely
affect GSK's right and ability to Develop, Manufacture and Commercialize Product
in the Field in the GSK Territory.

     Section 2.4 Grants to Myogen under GSK Intellectual Property.

          (a) Subject to the terms and conditions of this Agreement, GSK hereby
grants to Myogen: (i) a non-exclusive, royalty-free license under the GSK
Intellectual Property to

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make, have made, use, sell, offer for sale and import Compound and Product in
the Myogen Territory; and (ii) subject to Section 2.3, a non-exclusive,
royalty-free license under the GSK Intellectual Property to make, have made,
use, sell, offer for sale and import Compound and Product outside the Field in
the GSK Territory.

          (b)    (i) Myogen will have the right to sublicense any or all of its
rights under the GSK Intellectual Property as provided in Section 2.4(a) to its
Affiliates, without the consent of GSK.

               (ii) Myogen will have the right to sublicense its rights under
the GSK Intellectual Property as provided in Section 2.4(a) to Third Parties to
make, have made and import Compound and/or Product in the Myogen Territory and
to make, have made and import Compound and/or Product outside of the Field in
the GSK Territory, in each case upon providing prior written notice to GSK. If
GSK does not object to the sublicense by Myogen of its rights as provided in
this Section 2.4(b)(ii), or if GSK does not provide any response to Myogen, in
each case within [..**..] Business Days after receiving written notice thereof
from Myogen, Myogen will be free to sublicense its rights as set forth in this
Section 2.4(b)(ii). If GSK objects to the sublicense by Myogen of its rights as
provided in this Section 2.4(b)(ii) within [..**..] Business Days after
receiving written notice thereof from Myogen, Myogen will afford GSK with a
reasonable opportunity to meet and discuss with Myogen GSK's objection to such
sublicense, which objection Myogen will consider in good faith but to which
Myogen will have no obligation to comply.

               (iii) Myogen will have the right to sublicense any or all of its
other rights beyond those set forth in Section 2.4(b)(ii) above under the GSK
Intellectual Property as provided in Section 2.4(a) to Third Parties, upon
obtaining the prior written consent of GSK, which consent will not be
unreasonably withheld. Notwithstanding the foregoing, Myogen will have the right
at any time during the Term, to sublicense its rights under Section 2.4(a):

                    (A) to any Third Party who Myogen may engage to provide
services to or on behalf of Myogen relating to this Agreement (including a
Clinical Research Organization (CRO)), without the consent of GSK;

                    (B) to any Third Party who Myogen may engage as a
Wholesaler, without the consent of GSK;

                    (C) to any Third Party who Myogen may engage as a
Distributor of Product, without the consent of GSK; and

                    (D) to any Sublicensee with the prior written consent of GSK
which consent may not be unreasonably withheld;

provided, however that, except as set forth in Section 11.9(a)(iv), any
agreement entered into by Myogen pursuant to this Section 2.4(b)(iii) will
automatically terminate as to Product, without any action by Myogen or such
Third Party or Sublicensee, upon the termination of this Agreement.

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
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               (iv) Myogen will remain responsible for any breach by a
Sublicensee of the terms of this Agreement or the applicable sublicense
agreement. Any agreement entered into by Myogen pursuant to this Section 2.4(b)
will be in writing and will include provisions acknowledging that such agreement
is subject to the license granted to Myogen under this Agreement and that such
agreement shall be automatically terminated upon termination of this Agreement.
Myogen will provide GSK with a copy of each such agreement entered into by
Myogen pursuant to Section 2.4(b)(iii)(D).

     Section 2.5 Affiliates. Notwithstanding anything in this Agreement to the
contrary, either Party may contract or agree with one or more of its Affiliates
to have such Affiliate perform any of such Party's obligations herein. In no
event will such use of an Affiliate be deemed to relieve a Party of its
liabilities or obligations to the other Party under this Agreement; provided,
that performance of an obligation hereunder by an Affiliate of a Party will be
attributed to such Party. Each Party expressly acknowledges and agrees that it
will remain fully and unconditionally obligated and responsible for the full and
complete performance of all of its obligations under the terms and conditions of
this Agreement, whether or not such performance is carried out by such Party or
any of its Affiliates.

     Section 2.6 Abbott Agreement.GSK acknowledges that the sublicense granted
hereunder to GSK under the Abbott Intellectual Property is governed by the terms
of the Abbott Agreement. GSK agrees to abide by the terms and conditions of the
Abbott Agreement, where and to the extent applicable. Further, the Parties
acknowledge and agree as follows:

          (a) Pursuant to Section 3.2 of the Abbott Agreement, Abbott and its
Affiliates have the right to develop and commercialize the Compound for [..**..]
(the term [..**..] is defined in Section [..**..] of the Abbott Agreement).
Subject to any confidentiality restrictions imposed by Abbott, Myogen will
within five (5) Business Days inform GSK in writing of any consultation by
Abbott with Myogen regarding Abbott or its Affiliates conducting any research
and development activities involving the use of Compound in animals or humans in
which Abbott apprises Myogen of the scope and nature of such activities.
Further, subject to any confidentiality restrictions imposed by Abbott, Myogen
will within five (5) Business Days after receipt from Abbott, provide GSK with
copies of all studies relating to the Compound performed by Abbott or its
Affiliates, which shall be treated as the Confidential Information of Myogen and
subject to Article XIII.

          (b) To the extent permitted under Applicable Law, pursuant to Section
4.8 of the Abbott Agreement, in the event that the Abbott Agreement is
terminated by Abbott for any reason as set forth in Article 8 therein or by
Myogen under Section 8.2 therein, Abbott will have an exclusive license under
all [..**..] (as such term is defined in Section [..**..] of the Abbott
Agreement) made solely by GSK and/or its Affiliates.

          (c) Myogen will not, and will cause its Affiliates and Sublicensees
not to: (i) on its or their own or in agreement with Abbott, terminate the
Abbott Agreement or supplement, amend or modify the Abbott Agreement in any way
that materially and adversely affects GSK rights under the Abbott Intellectual
Property or in this Agreement without the prior written

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
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EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
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consent of GSK; provided, however, that Myogen will provide GSK with written
notice prior to making any amendment to the Abbott Agreement; (ii) initiate any
dispute resolution proceedings with Abbott under the Abbott Agreement without
the prior written consent of GSK, which shall not be unreasonably withheld; or,
(iii) send written notice to Abbott of any monetary or non-monetary breach by
Abbott of the Abbott Agreement as provided in Section 8.3 of the Abbott
Agreement without providing at least ten (10) calendar days' prior written
notice to GSK.

          (d) Within two (2) Business Days of receiving written notice of a
monetary breach or non-monetary material breach from Abbott as provided in
Section 8.3 of the Abbott Agreement, Myogen will provide GSK with a copy of such
notice and meet with GSK upon GSK's request to discuss whether a material breach
has occurred, whether Myogen should challenge the existence of the breach by
invoking the ADR (as defined in the Abbott Agreement) procedure set forth in
Exhibit D of the Abbott Agreement (which Myogen will not do without prior
consultation with GSK) and the options to cure such breach, if applicable. GSK
may, in its sole discretion but after consultation with Myogen, determine to
cure any such breach of Myogen under the Abbott Agreement if Myogen has not
already done so; provided, however, that (i) if GSK cures any monetary breach of
Myogen, GSK will have the right to credit all of such amount paid to Abbott
against any Milestone Payments and/or Royalties owed to Myogen as provided in
Article IX of this Agreement; and (ii) if GSK cures any non-monetary breach of
Myogen, GSK will have the right to credit any and all reasonable, documented
direct costs and expenses incurred by GSK in curing such non-monetary breach
against any Milestone Payments and/or Royalties owed to Myogen as provided in
Article IX of this Agreement; however, in the case of (i) and (ii) above, only
to the extent that such breach was not directly or indirectly a result of an act
or omission by GSK, its Affiliates or sublicensees, including any breach of this
Agreement.

     Section 2.7 Reservation of Rights. No right or license under any
intellectual property right Controlled by either Party is granted or implied
except as expressly granted in this Agreement. Except for the rights
specifically granted in this Agreement, each Party expressly reserves all rights
Controlled by it or its Affiliates to all its products and intellectual
property, and reserves the right to utilize or allow its Affiliates or Third
Parties to utilize such products and intellectual property rights in any manner
not inconsistent with the terms of this Agreement.

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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                                   ARTICLE III

                                   GOVERNANCE

     Section 3.1 Joint Steering Committee.

          (a) Within fifteen (15) Business Days after the Effective Date, the
Parties will form a committee (the "Joint Steering Committee"), which will serve
as a global oversight committee that is responsible for establishing, reviewing
and revising (i) the overall Development strategy for Compound and Product in
the Field in the Territory, with input from the Joint Project Team, including,
without limitation, approval of all updates and revisions to the Development
Plan as provided in Section 4.1; (ii) the overall Commercialization strategy for
Compound and Product in the Field in the Territory (other than pricing and
reimbursement for Product), with input from the Global Brand Team; and (iii) the
overall Manufacturing strategy for Compound and Product in the Field in the
Territory. The Joint Steering Committee will oversee the activities of the Joint
Project Team and Global Brand Team, and will settle unresolved disputes or
disagreements of the Joint Project Team and Global Brand Team.

          (b) Each Party will designate at least three (3) and up to five (5)
representatives for membership on the Joint Steering Committee. Each Party's
representatives on the Joint Steering Committee will be employees from among the
project management, clinical, regulatory, commercial and alliance management
departments of such Party and will have the authority to make decisions on
behalf of such Party within the constraints of necessary internal approvals
(which will have been previously obtained to the extent practicable). Each Party
will have one (1) vote on each matter brought before the Joint Steering
Committee. At least three (3) members from each Party (or their designees with
the authority to make decisions on behalf of such Party) must be present at a
meeting of the Joint Steering Committee to represent a quorum for voting
purposes. Each Party may from time to time and in their sole discretion include
additional non-voting ad-hoc representatives to participate in Joint Steering
Committee meetings to address specific issues. The Joint Steering Committee will
be co-chaired by a Myogen member of the Joint Steering Committee and a GSK
member of the Joint Steering Committee and each Party may, from time to time and
in its sole discretion, change the member of such Party who serves as such
Party's designee for co-chairperson of the Joint Steering Committee.

          (c) The first meeting of the Joint Steering Committee may be a face to
face meeting at a location agreed to by the Parties and will occur within twenty
(20) Business Days after formation of the Joint Steering Committee; provided,
however that if the first meeting of the Joint Steering Committee is not face to
face, the next meeting of the Joint Steering Committee, which must occur within
the immediately succeeding Calendar Quarter, must be a face to face meeting at a
location agreed to by the Parties. The purpose of the initial meeting will be to
agree on an operational charter that will set forth the principles and
guidelines for the governance and operation of the Joint Steering Committee
(e.g., how the co-chairs of the Joint Steering Committee will share
responsibilities for determining meeting agendas and the drafting of minutes,
etc.). Thereafter, meetings will be held at least once during each Calendar
Quarter, or more or less frequently as the Joint Steering Committee members may
agree. The location of

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<PAGE>

such meetings will alternate between sites selected by Myogen and GSK, unless
otherwise agreed upon between the Parties. Joint Steering Committee meetings
need not necessarily be face-to-face meetings but, upon the agreement of both
Parties, can be via other methods of communication such as teleconferences
and/or videoconference. Each Party will bear all expenses it incurs in regard to
participating in all meetings of the Joint Steering Committee, including all
travel and living expenses. Minutes of each Joint Steering Committee meeting
will be prepared as agreed to by the co-chairpersons and distributed to the
members of the Joint Steering Committee for review and comment within twenty
(20) Business Days after each meeting of the Joint Steering Committee, and will
be approved as the first order of business at the immediately succeeding Joint
Steering Committee meeting.

          (d) All decisions of the Joint Steering Committee will be by unanimous
vote, which decisions will be final and binding on the Parties. Should the
members of the Joint Steering Committee become deadlocked on an issue after a
good faith but unsuccessful effort to break such deadlock, the issue will be
presented to the senior management of Myogen and GSK as follows for resolution,
which resolution will be final and binding on the Parties: (i) to the chief
executive officer of Myogen or his/her designee and the head of the
cardiovascular therapeutic area within the research and development organization
at GSK or his/her designee for issues involving the Development of Compound
and/or Product; and (ii) to the chief executive officer of Myogen or his/her
designee and the president of pharmaceuticals for Europe at GSK or his/her
designee for all issues other than those relating to Development of Compound
and/or Product. If the dispute remains unresolved after thirty (30) Business
Days following the date on which such dispute is referred to the senior
management of each Party as provided in this Section 3.1(d), then (w) Myogen
will make the final and binding decision with respect to any dispute involving
the Development, Manufacture and Commercialization of Compound and/or Product in
the Myogen Territory, provided that such decision cannot be inconsistent with
the terms of this Agreement, the Development Plan and the Global Marketing Plan,
and such decision cannot materially and adversely affect GSK's right and ability
to Develop, Manufacture and Commercialize Product in the GSK Territory; (x) GSK
will make the final and binding decision with respect to any dispute involving
the Development, Manufacture and Commercialization of Compound and/or Product in
the GSK Territory, provided that such decision cannot be inconsistent with the
terms of this Agreement, the Development Plan and the Global Marketing Plan, and
such decision cannot materially and adversely affect Myogen's right and ability
to Develop, Manufacture and Commercialize Product in the Myogen Territory; (y)
any such decision, to the extent not specific to the Myogen Territory or the GSK
Territory, will be resolved in accordance with Section 14.1; and (z) any and all
issues relating to safety will be resolved as set forth in Section 3.4.

           (e) The Joint Steering Committee will have only such powers as are
specifically delegated to it in this Agreement, and will have no power to amend
this Agreement or waive a Party's rights or obligations under this Agreement.

     Section 3.2 Joint Project Team.

          (a) Within thirty (30) Business Days after the Effective Date, the
Parties will form a team (the "Joint Project Team") whose mandate will be to (i)
make strategic and

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operational recommendations to the Joint Steering Committee on matters relating
to the Development of Compound and Product in the Field in the Territory; (ii)
update the Development Plan during each Calendar Year and obtain the Joint
Steering Committee's approval of all such updates to the Development Plan, as
provided in Section 4.1; and (iii) oversee, manage and implement the Development
of Product in the Field in the Territory as provided in Article 4, including,
without limitation, appropriate safety reporting systems, pre-commercial
manufacturing and technology transfer.

          (b) Each Party will designate at least three (3), but not more than
five (5) representatives for membership on the Joint Project Team. Each Party
may, from time to time and in their sole discretion, determine from which
departments of such Party (e.g., scientific, clinical development, commercial
development, regulatory, manufacturing, etc.) representatives on the Joint
Project Team will come. Each Party will have one (1) vote on each matter brought
before the Joint Project Team. At least three (3) members from each Party (or
their designees with the authority to make decisions on behalf of such Party)
must be present at a meeting of the Joint Project Team to represent a quorum for
voting purposes. Each Party may from time to time and in their sole discretion
include additional non-voting ad-hoc representatives to participate in Joint
Project Team meetings to address specific issues. The Joint Project Team will be
co-chaired by a Myogen member and a GSK member.

          (c) The first meeting of the Joint Project Team may be a face to face
meeting at a location agreed to by the Parties will occur within twenty (20)
Business Days after formation of the Joint Project Team; provided, however that
if the first meeting of the Joint Project Team is not face to face, the next
meeting of the Joint Project Team, which must occur within the immediately
succeeding Calendar Quarter, must be a face to face meeting at a location agreed
to by the Parties. The purpose of the initial meeting will be to agree on an
operational charter that will set forth the principles and guidelines for the
governance and operation of the Joint Project Team (e.g., how the co-chairs of
the Joint Project Team will share responsibilities for determining meeting
agendas and the drafting of minutes, etc.). Thereafter, meetings will be held at
least once during each Calendar Quarter, or more or less frequently as the Joint
Project Team members may agree. The location of such meetings will alternate
between sites selected by Myogen and GSK, unless otherwise agreed upon between
the Parties. Joint Project Team meetings need not necessarily be face-to-face
meetings but, upon the agreement of both Parties, can be via other methods of
communication such as teleconferences and/or videoconference; provided, however
that unless otherwise agreed to by the Parties, Joint Project Team meetings will
be face-to-face meetings not less than twice per year. Each Party will bear all
expenses it incurs in regard to participating in all meetings of the Joint
Project Team, including all travel and living expenses. Minutes of each Joint
Project Team meeting will be prepared as agreed to by the co-chairpersons and
distributed to the members of the Joint Project Team for review and comment
within twenty (20) Business Days after each meeting of the Joint Project Team,
and will be approved as the first order of business at the immediately
succeeding Joint Project Team meeting.

          (d) All decisions of the Joint Project Team will be by unanimous vote,
which decision will be final and binding on the Parties. Should the members of
the Joint Project Team become deadlocked on an issue after a good faith but
unsuccessful effort to break such deadlock,

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the issue will be presented to the Joint Steering Committee for resolution as
set forth in Section 3.1(d).

     Section 3.3 Global Brand Team.

          (a) Within thirty (30) Business Days after the Effective Date, the
Parties will form a team (the "Global Brand Team") whose mandate will be to (i)
make strategic and operational recommendations to the Joint Steering Committee
on matters relating to the Commercialization of Compound and Product in the
Field in the Territory; (ii) draft the initial Global Marketing Plan, and update
such Global Marketing Plan during each Calendar Year and obtain the Joint
Steering Committee's approval of any such updates to the Global Marketing Plan,
as provided in Section 5.1; and (iii) oversee the Commercialization of Product
in the Field in the Territory by the Parties as provided in Article 5.

          (b) Each Party will designate at least three (3), but not more than
five (5) representatives for membership on the Global Brand Team. Each Party
may, from time to time and in their sole discretion, determine from which
departments of such Party representatives on the Global Brand Team will come.
Each Party will have one (1) vote on each matter brought before the Global Brand
Team. At least three (3) members from each Party (or their designees with the
authority to make decisions on behalf of such Party) must be present at a
meeting of the Global Brand Team to represent a quorum for voting purposes.
Either Party may from time to time and in their sole discretion include
additional non-voting ad-hoc representatives to participate in Global Brand Team
meetings to address specific issues. The Global Brand Team will be co-chaired by
a Myogen member and a GSK member.

          (c) The first meeting of the Global Brand Team will be a face to face
meeting at a location agreed to by the Parties and will occur within twenty (20)
Business Days after formation of the Global Brand Team. The purpose of the
initial meeting will be to agree on an operational charter that will set forth
the principles and guidelines for the governance and operation of the Global
Brand Team (how the co-chairs of the Global Brand Team will share
responsibilities for determining meeting agendas and the drafting of minutes,
etc.). Thereafter, meetings will be held at least once during each Calendar
Quarter, or more or less frequently as the Global Brand Team members may agree.
The location of such meetings will alternate between sites selected by Myogen
and GSK, unless otherwise agreed upon between the Parties. Global Brand Team
meetings need not necessarily be face-to-face meetings but, upon the agreement
of both Parties, can be via other methods of communication such as
teleconferences and/or videoconference. Each Party will bear all expenses it
incurs in regard to participating in all meetings of the Global Brand Team,
including all travel and living expenses. Minutes of each Global Brand Team
meeting will be prepared as agreed to by the co-chairpersons and distributed to
the members of the Global Brand Team for review and comment within twenty (20)
Business Days after each meeting of the Global Brand Team, and will be approved
as the first order of business at the immediately succeeding Global Brand Team
meeting.

          (d) All decisions of the Global Brand Team will be by unanimous vote,
which decision will be final and binding on the Parties. Should the members of
the Global Brand Team become deadlocked on an issue after a good faith but
unsuccessful effort to break such deadlock,

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the issue will be presented to the Joint Steering Committee for resolution as
set forth in Section 3.1(d).

     Section 3.4 Decisions Relating to Safety Concerns.

          (a) Development Activities. If a Party (the "requesting Party")
reasonably believes that patient safety may be compromised in any ongoing or
proposed or planned Development activity of the other Party involving a clinical
trial for the Product (the "developing Party"), such requesting Party may send
written notice to the developing Party requesting that the developing Party
modify, discontinue or not initiate, as applicable, such Development activity
(including, without limitation, any clinical trial) in the Territory. If the
developing Party does not modify or discontinue the conduct or planning of any
such Development activity within thirty (30) Business Days (or such shorter
period as may be required by applicable Regulatory Authorities) after receipt of
written request from the requesting Party as provided in this Section 3.4(a),
the requesting Party may request that such matter be presented to an independent
safety board for resolution. The independent safety board panel will be
comprised of three (3) panelists, one (1) of whom will be selected by GSK, one
(1) of whom will be selected by Myogen, and one (1) of whom will be selected by
the two (2) panelists selected by the Parties. No panelist of the independent
advisory board may be an employee of either Party or shall have had an
employment or consulting relationship with either Party within five (5) years of
his/her appointment. Each panelist shall disclose his/her prior employment and
consulting relationships and must have a background in clinical safety issues.
Each Party will bear the cost of its own designated panelist on the independent
safety board and will equally share the cost of the third panelist selected by
the other panelists. The Parties must present such matter to the independent
safety board for resolution within thirty (30) Business Days after a request is
made by the requesting Party, which decision of the independent safety board
regarding the continuation of any such Development activity must be agreed to by
a majority of the panelists and will be binding on the Parties.

          (b) Commercialization Activities. Without prejudice to the provisions
contained in Section 8.1(a), if GSK reasonably believes that patient safety may
be compromised at any time after the First Commercial Sale, GSK may terminate
this Agreement in accordance with Section 11.3.

          (c) Notification of Safety Concerns. After a Party reasonably believes
that patient safety may be compromised with respect to Product in the Field in
the Territory as described in Section 3.4(a) or 3.4(b), such Party will promptly
notify the other Party. Within two (2) Business Days after such notice is sent
by a Party, the Joint Steering Committee will meet to discuss how the Parties
will address the patient safety concern, whether as provided in Sections 3.4(a)
and 3.4(b) or in some other manner.

                                   ARTICLE IV

                       DEVELOPMENT AND REGULATORY FILINGS

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     Section 4.1 Development Plan. The initial Development Plan which has been
agreed to by the Parties as of the Effective Date, has been exchanged by the
Parties under separate cover. Not later than sixty (60) Business Days prior to
the end of each Calendar Year during the Term in which the Development Plan is
applicable, the Joint Project Team will update the Development Plan as required
and submit the updated Development Plan for review and approval by the Joint
Steering Committee.

     Section 4.2 Clinical/Non-Clinical Development Under the Development Plan.

           (a) Myogen will be solely responsible for conducting all clinical and
non-clinical Development activities that, as of the Effective Date, the Parties
believe are required in order for Myogen to obtain and maintain Regulatory
Approvals for Product in the Field in the United States as set forth in Section
4.4(b) and that, as of the Effective Date, the Parties believe are required in
order for GSK or its Affiliates to obtain and maintain Regulatory Approvals for
Product in the Field in Canada and the European Economic Area as set forth in
Section 4.4(a), in each case as set forth in the Development Plan exchanged by
the Parties on the Effective Date and in accordance with this Agreement, and as
directed by the Joint Project Team. The Development Plan exchanged by the
Parties on the Effective Date sets forth all such clinical and non-clinical
Development activities that the Parties believe are required in order for Myogen
to obtain and maintain Regulatory Approvals for Product in the Field in the
United States as set forth in Section 4.4(b) and that the Parties believe are
required in order for GSK or its Affiliates to obtain and maintain Regulatory
Approvals for Product in the Field in Canada and the European Economic Area as
set forth in Section 4.4(a), which Development activities will be conducted by
or on behalf of Myogen at Myogen's sole cost and expense (provided that Myogen
shall not be required to pay regulatory filing, submission or similar fees
relating to the GSK Territory). To the extent that Myogen initiates any such
Development activities after the Effective Date, Myogen will share the design of
any such Development activities with GSK and provide GSK with a reasonable
opportunity to review, comment on and modify such design in a manner consistent
with the requirements necessary for GSK to obtain and maintain Regulatory
Approval for Product in the Field in the GSK Territory. All clinical and
non-clinical Development activities other than as set forth in the Development
Plan exchanged by the Parties on the Effective Date or as provided in Section
4.4 shall be deemed to be New Development Activities and Myogen and GSK shall be
responsible for the costs and expenses related to such New Development
Activities as provided in Section 4.3. Myogen will preserve any and all raw data
generated from non-Good Laboratory Practices (GLP) studies, including, without
limitation, pharmacology studies and absorption, distribution, metabolism and
excretion (ADME) studies, until such time that GSK determines such raw data is
no longer needed by GSK or its Affiliates to obtain or maintain Regulatory
Approvals in the GSK Territory as provided in Section 4.4(a). After such time,
Myogen will notify GSK in writing prior to destroying any such raw data and
offer GSK an opportunity to retain such raw data at GSK's sole cost and expense.

          (b) Except as otherwise provided in Section 4.2(a) above, GSK will be
solely responsible for conducting all clinical and non-clinical Development
activities that are required in order for GSK or its Affiliates to obtain and
maintain Regulatory Approvals for Product in all countries in the GSK Territory
in accordance with this Agreement and as directed by the Joint Project Team.
Such Development activities shall be conducted by or on behalf of GSK at GSK's

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sole cost and expense. Notwithstanding the foregoing, Myogen will, as reasonably
requested by GSK and at Myogen's sole cost and expense (provided that documented
fees and expenses of any Third Party will be billed at cost to GSK), provide
support to GSK with respect to clinical and non-clinical Development activities
required to obtain and maintain Regulatory Approvals for Product in the GSK
Territory.

          (c) Each Party, as applicable, will use Commercially Reasonable
Efforts to execute and to perform, or cause to be performed, their respective
Development activities set forth in the Development Plan, in each case, in
compliance with Applicable Law, Good Clinical Practice and Good Laboratory
Practice. Each Party will at no cost or expense to the other Party provide such
other Party with copies of or access to any and all Development Information
generated or otherwise obtained (including information generated or obtained by
Affiliates or any Third Party on behalf of a Party, provided that the fees and
expenses of any Third Party will be billed at cost to the requesting Party) in
the Development of Compound and/or Product as provided in this Section 4.2
(including Development Information generated or otherwise obtained by GSK and/or
its Affiliates to support the initial JNDA filing), all of which Development
Information may be used by or on behalf of each Party in the Development,
Manufacture and/or Commercialization of Compound and/or Product in their
respective Territories, including, without limitation, in the preparation,
submission, filing, prosecution and maintenance of Regulatory Approvals for
Product in their respective Territories. Moreover, upon reasonable written
notice from a Party, the other Party will provide Regulatory Authorities with
access to any Development Information for inspection and/or review as may be
required under Applicable Law.

     Section 4.3 Development Outside of the Development Plan.

          (a) If, during the Term, either Party desires to Develop the Compound
and/or Product in the Field for new indications, new formulations, publication
purposes or any purpose other than as provided in the Development Plan (a "New
Development Activity"), such Party must submit its proposed development plan for
such New Development Activity, including, without limitation the proposed budget
of all costs thereof, for review and approval by the Joint Steering Committee.

          (b) If the Joint Steering Committee approves the proposed plan and
budget for a New Development Activity (a "Joint New Development Activity"), then
prior to the commencement of any such Joint New Development Activity, the
Parties, through the Joint Project Team, will use Commercially Reasonable
Efforts to draft and agree to a comprehensive development plan and budget for
such Joint New Development Activity that are consistent with the proposed
development plan that was provided to the Joint Steering Committee as provided
in Section 4.3(a). The Parties acknowledge and agree that (i) each Party will be
responsible for its own internal costs associated with such Joint New
Development Activity; (ii) GSK will only be obligated to pay for those actual
external costs for such Joint New Development Activity that are equal to the
greater of (A) [..**..] of such actual external costs, or (B) if sales have
commenced in both the GSK Territory and the Myogen Territory, [..**..] such
actual external costs [..**..] the gross sales of Product in the Field in the
GSK Territory for the immediately preceding Calendar Year [..**..] the gross
sales of Product in the Field in the Territory for the immediately

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preceding Calendar Year, in each case calculated by the Parties in accordance
with generally accepted accounting principles; and (iii) Myogen will be
obligated to pay for all actual external costs for such Joint New Development
Activity which GSK is not obligated to pay for as provided in (ii) above. The
Parties will conduct any Joint New Development Activity in accordance with the
development plan, the budget prepared as provided in this Section 4.3(b) and the
terms and conditions of this Agreement, and as directed by the Joint Project
Team and Joint Steering Committee.

           (c) If the Joint Steering Committee does not approve the proposed plan
and/or budget for a New Development Activity and Myogen nonetheless desires to
conduct such New Development Activity (a "Myogen Sponsored New Development
Activity"), Myogen may conduct such Myogen Sponsored New Development Activity
only within the Myogen Territory; provided, however that Myogen may conduct
clinical/non-clinical activities relating to such Myogen Sponsored New
Development Activity in the GSK Territory upon obtaining GSK's prior written
consent, which will not be unreasonably withheld. Prior to conducting such
Myogen Sponsored New Development Activity, Myogen will draft a comprehensive
development plan and budget for such Myogen Sponsored New Development Activity
that is consistent with the proposed development plan submitted to the Joint
Steering Committee as provided in Section 4.3(b), which will be presented to the
Joint Project Team for review and comment. Myogen will conduct any such Myogen
New Development Activity in accordance with the development plan and budget
prepared as provided in this Section 4.3(c), the terms and conditions of this
Agreement. Myogen will be solely responsible for conducting, and paying all
costs and expenses related to, a Myogen Sponsored New Development Activity. Upon
Myogen's completion of a Myogen Sponsored New Development Activity, Myogen will
provide GSK with access to any and all Development Information generated by or
on behalf of Myogen during such Myogen Sponsored New Development Activity, all
of which Development Information may be used by or on behalf of GSK in the
Development, Manufacture and/or Commercialization of Compound and/or Product in
the Field in the GSK Territory, including, without limitation, in the
preparation, submission, filing, prosecution and maintenance of Regulatory
Approvals for Product in the Field in the GSK Territory; provided, however, that
GSK first pays to Myogen an amount equal to what GSK's funding contribution
would have been as provided in Section 4.3(b)(i) had the Joint Steering
Committee approved such New Development Activity, plus [..**..] of such amount.

          (d) If the Joint Steering Committee does not approve the proposed plan
and/or budget for a New Development Activity and GSK nonetheless desires to
conduct such New Development Activity (a "GSK Sponsored New Development
Activity"), GSK may conduct such GSK Sponsored New Development Activity only
within the GSK Territory; provided, however that GSK may conduct
clinical/non-clinical activities relating to such GSK Sponsored New Development
Activity in the Myogen Territory only upon obtaining Myogen's prior written
consent, which will not be unreasonably withheld. Prior to conducting such GSK
Sponsored New Development Activity, GSK will draft a comprehensive development
plan and budget for such GSK Sponsored New Development Activity that is
consistent with the proposed development plan submitted to the Joint Steering
Committee as provided in Section 4.3(b), which will be presented to the Joint
Project Team for review and comment. GSK will conduct any such GSK New
Development Activity in accordance with the development plan and budget

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prepared as provided in this Section 4.3(d), the terms and conditions of this
Agreement. GSK will be solely responsible for conducting, and paying all costs
and expenses related to, a GSK Sponsored New Development Activity. Upon GSK's
completion of a GSK Sponsored New Development Activity, GSK will provide Myogen
with access to any and all Development Information generated by or on behalf of
GSK during such GSK Sponsored New Development Activity, all of which Development
Information may be used by or on behalf of Myogen in the Development,
Manufacture and/or Commercialization of Compound and/or Product in the Field in
the Myogen Territory, including, without limitation, in the preparation,
submission, filing, prosecution and maintenance of Regulatory Approvals for
Product in the Field in the Myogen Territory; provided, however that Myogen
first pays to GSK an amount equal to what Myogen's funding contribution would
have been as provided in Section 4.3(b)(ii) had the Joint Steering Committee
approved such New Development Activity, plus [..**..] of such amount.

     Section 4.4 Regulatory Approvals.

          (a) Subject to Section 6.4, GSK will, in accordance with the
Development Plan and as directed by the Joint Project Team, be solely
responsible for at its sole expense, using Commercially Reasonable Efforts, for
the preparation, submission, filing, prosecution and maintenance, in its own
name or in the name of any of its Affiliates or sublicensees, of all Regulatory
Approvals for Compound and Product in the Field in the GSK Territory.

          (b) Myogen will, in accordance with the Development Plan and as
directed by the Joint Project Team, be solely responsible for, at its sole
expense, the preparation, submission, filing, prosecution and maintenance, in
its own name or in the name of any of its Affiliates or sublicensees, of all
Regulatory Approvals for Compound and Product in the Field in the Myogen
Territory.

          (c) Notwithstanding the foregoing, each Party agrees and acknowledges
that it will, as reasonably requested by the other Party from time to time
during the Term, assist the other Party with the preparation of the Common
Technical Document. Further, Myogen will, as reasonably requested by GSK from
time to time during the Term, (i) assist GSK with the preparation of responses
to questions by Regulatory Authorities regarding Compound and/or Product in the
Field in the GSK Territory; and (ii) provide support to GSK during the
preparation, filing, prosecution and maintenance of Regulatory Approvals for
Compound and Product in the Field in the GSK Territory, in each case at Myogen's
sole cost and expense; provided, however that the reasonable, documented direct
fees and expenses of any Third Party incurred by Myogen in connection with such
assistance will be [..**..] GSK.

          (d) Except with respect to a Myogen Sponsored New Development
Activity, unless GSK has paid the funding contribution, if required, as set
forth in Section 4.3(c), Myogen will promptly furnish GSK with copies of all
substantive Regulatory Authority outputs relating to the Development of, and/or
filing of Regulatory Approvals for, Compound and/or Product in the Myogen
Territory (including, without limitation, all substantive correspondence with
such Regulatory Authorities, responses from such Regulatory Authorities,
requests for information from such Regulatory Authorities, briefing documents
and other materials relating to interactions with such Regulatory Authorities,
and summaries of outputs resulting from substantive

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correspondence/ conversations or meetings with such Regulatory Authorities).

          (e) Except with respect to a GSK Sponsored New Development Activity,
unless Myogen has paid the funding contribution, if required, as set forth in
Section 4.3(d), GSK will promptly furnish Myogen with copies of all substantive
Regulatory Authority outputs relating to the Development of, and/or filing of
Regulatory Approvals for, Compound and/or Product in the GSK Territory
(including, without limitation, all substantive correspondence with such
Regulatory Authorities, responses from such Regulatory Authorities, requests for
information from such Regulatory Authorities, briefing documents and other
materials relating to interactions with such Regulatory Authorities, and
summaries of outputs resulting from substantive correspondence/ conversations or
meetings with such Regulatory Authorities).

                                    ARTICLE V

                                COMMERCIALIZATION

     Section 5.1 Global Marketing Plan. As directed by the Joint Steering
Committee, the Global Brand Team will draft the initial Global Marketing Plan
and submit the initial Global Marketing Plan to the Joint Steering Committee for
review and approval. Thereafter, not later than sixty (60) Business Days prior
to the end of each Calendar Year during the Term, the Global Brand Team will
update the Global Marketing Plan as required and submit the updated Global
Marketing Plan for review and approval by the Joint Steering Committee.

     Section 5.2 Commercialization of Product in the GSK Territory.

          (a) (i) GSK will have full control, authority and responsibility for
the Commercialization of Product in the Field in the GSK Territory. Subject to
Section 6.4, GSK will exercise its Commercially Reasonable Efforts in
Commercializing Product in countries of the GSK Territory where it has obtained
Regulatory Approval in a manner consistent with this Agreement and the Global
Marketing Plan, and, with respect to the Major Countries and Major European
Market Countries only, as directed by the Global Brand Team. Notwithstanding
anything in this Section 5.2(a) or in this Agreement to the contrary, GSK will
have final decision-making authority, in its sole discretion, relating to the
Commercialization of Product in the Field in the GSK Territory, including,
without limitation, pricing and reimbursement for Product (as provided in
Section 5.2(c)), Product advertising and promotional materials, Product
packaging, sales force training and all interactions with Regulatory Authorities
regarding the Commercialization of Product in the Field; provided, however that
any such decisions of GSK relating to the Commercialization of Product in the
Field in the GSK Territory, to the extent not required by a Regulatory Authority
or under Applicable Law, will not be inconsistent with the Global Marketing Plan
or the terms of this Agreement, and will not materially and adversely affect
Myogen's Development, Manufacture and/or Commercialization of Product in the
Field in the Myogen Territory, or subject to Section 2.3, Myogen's retained
right to make, have made, use, sell, offer for sale and/or import Product
outside of the Field in the GSK Territory.

               (ii) If, at any time during the Term, Myogen reasonably believes
that

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GSK has failed to use Commercially Reasonable Efforts in Commercializing Product
in a country in the GSK Territory as set forth in Section 5.2(a)(i), Myogen may
(A) with respect to any Major Country or Major European Market Country, exercise
its rights under Section 6.2, and (B) with respect to any country other than a
Major Country or Major European Market Country, exercise its rights under
Section 11.2 to terminate this Agreement but only with respect to such affected
country and in such an event, such terminated country will be removed from the
GSK Territory and included within the Myogen Territory and the provisions
contained in Section 11.9(a) shall apply to such termination.

          (b) GSK will book all sales of Product in the Field in the GSK
Territory and will warehouse and distribute the Product in the Field in the GSK
Territory; provided, however, that GSK will be permitted to warehouse Product in
the Field in the Myogen Territory if such Product has been Manufactured by or on
behalf of GSK in the Myogen Territory. If Myogen receives any orders for Product
for sale in the Field in the GSK Territory, it will refer such orders to GSK. If
Product sold in the Field in the GSK Territory is returned to Myogen, Myogen
will promptly ship such returned Product to a facility designated by GSK.

          (c) Subject to the terms of this Agreement, including, without
limitation, Section 6.4, and the Global Marketing Plan, (i) GSK will be solely
responsible for, using Commercially Reasonable Efforts, all pricing and
reimbursement approval proceedings relating to the Product in the Field in the
GSK Territory, and (ii) GSK will have complete discretion in setting pricing for
the Product in the Field in the GSK Territory. GSK will be responsible for
filing and maintenance fees relating to pricing and reimbursement approvals.

          (d) (i) Subject to Applicable Law and the Global Marketing Plan, GSK
will, in its sole discretion, determine and select all trademarks, tradenames,
copyrights, logos (collectively, "GSK Marks"), used in connection with Product
in the Field in the GSK Territory and will, as part of GSK's annual updates to
the Global Marketing Plan, keep Myogen informed of GSK's plans with respect to
existing and planned GSK Marks. For the avoidance of doubt, the term "GSK Marks"
will in no way be deemed to include the Myogen Trademarks.

               (ii) Myogen hereby grants to GSK an exclusive, royalty free
license, with the right to grant sublicenses, to use the Myogen Trademarks to
Develop, Manufacture and Commercialize Compound and/or Product in the Field in
the GSK Territory during the Term. GSK will use the Myogen Trademarks solely
with respect to the Development, Manufacture and/or Commercialization of
Compound and/or Product in the Field and in accordance with the standards of
quality established or approved in writing by Myogen and provided to GSK.
Whenever GSK uses the Myogen Trademarks in any manner in connection with
Product, Myogen will clearly indicate that the Myogen Trademarks are owned by
Myogen. When using the Myogen Trademarks under this Agreement, GSK will comply
with all Applicable Law pertaining to the Myogen Trademarks in force at any time
in the GSK Territory. During the Term, GSK will provide Myogen with copies of
promotional materials on a periodic basis, as requested by Myogen, for review of
the use of the Myogen Trademarks by GSK. GSK will use Commercially Reasonable
Efforts to promptly take any and all actions directed by Myogen with respect to
GSK's use of the Myogen Trademarks that are reasonably designed to ensure
compliance with the provisions of this Section 5.2(d)(ii).

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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                    (A) GSK acknowledges and agrees that Myogen and/or its
Affiliates, is, and at all times will remain the owner of the Myogen Trademarks.
GSK will not at any time do, cause to be done, or permit any of its employees,
agents, contractors and subcontractors to commit any act inconsistent with,
contesting or in any way impairing, or tending to impair, such ownership. GSK
agrees that all use of the Myogen Trademarks by GSK will inure to the benefit of
and be on behalf of Myogen or Myogen's Affiliates. GSK acknowledges that nothing
in this Agreement will give GSK any right, title or interest in the Myogen
Trademarks other than the right to use the Myogen Trademarks within the GSK
Territory in accordance with this Agreement. GSK agrees that it will not
challenge Myogen's or Myogen's Affiliates' title to, or ownership of, the Myogen
Trademarks, or attack or contest the validity of the Myogen Trademarks. All
goodwill accruing to the Myogen Trademarks as a result of the use of the Myogen
Trademarks in the performance of this Agreement will belong solely to Myogen or
Myogen's Affiliates. In the event that GSK acquires any rights in the Myogen
Trademarks in connection with GSK's activities pursuant to this Agreement, GSK
will assign, and hereby does assign, to Myogen or Myogen's Affiliates all such
rights, including any related goodwill.

                    (B) GSK is limited to using the Myogen Trademarks in
connection with the Internet as follows:

                         (1) the use must be in compliance with local rules
regarding advertising of pharmaceuticals on the Internet;

                         (2) the use of any Myogen Trademarks as a domain name
is limited to the relevant country code domain within the GSK Territory. No
license is granted to use the ".com generic code domain" or any other such
top-level domain. All domain names containing the Myogen Trademark will be
registered and maintained by and in the name of Myogen or its designee;

                         (3) the use of any Myogen Trademarks as a domain name
is limited to use on websites with universal resource locaters using the
relevant country code domain within the GSK Territory and aimed at audiences in
those countries in the GSK Territory;

                         (4) appropriate disclaimers must be included in any
website to the effect that it is intended for residents in that country within
the GSK Territory only; and

                         (5) in using any of the Myogen Trademarks as a domain
name or on the Internet, GSK will not have and will not represent in any way
that it has any title or right to the ownership or registration or their use,
except as provided in this Agreement. GSK will at all times indicate that each
of the Trademarks is a trademark of Myogen and is used under license.

          (e) Upon GSK's request, the Parties will, through the Global Brand
Team and

[..**..] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED
BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF
1934, AS AMENDED.


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in the Global Marketing Plan, use good faith efforts to negotiate ways in which
Myogen may assist GSK in the Commercialization of Product in the Field in the
GSK Territory during the Term at no cost or expense to GSK except as agreed in
advance to defer the incremen