UNC/NIIGATA/PANACOS LICENSE AGREEMENT

Exhibit 10.3

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UNC/NIIGATA/PANACOS LICENSE AGREEMENT

UNC/NIIGATA/PANACOS LICENSE AGREEMENT (this “Agreement”), effective as of January 20, 2009 (the “Effective Date”), between THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL having an address at CB #4105, 308 Bynum Hall, Chapel Hill, NC (hereinafter referred to as “University”), NIIGATA UNIVERSITY OF PHARMACY AND APPLIED LIFE SCIENCES having an address at 5-13-2 Kamishin’Ei-cho Niigata 950-2081, Japan (“Niigata”) and PANACOS PHARMACEUTICALS, INC., a corporation organized and existing under the laws of Delaware and having an address at 209 Perry Parkway, Gaithersburg, MD 20877 (together with its Affiliates hereinafter referred to as “Licensee”).

WITNESSETH

WHEREAS, University owns and controls its share of the ownership interest in the inventions covered by the Patents listed in Appendix A attached hereto (“University Inventions”), developed jointly by University and Licensee pursuant to the Sponsored Research Agreement, and Niigata owns and controls its share of the ownership interest in the inventions covered by the Patent listed on Appendix B attached hereto (“Niigata Inventions”) (University Inventions and Niigata Inventions hereinafter collectively referred to as “Inventions”); and

WHEREAS substantially concurrently with the execution and delivery of this Agreement, (i) Licensee and Myriad Genetics, Inc. (“Myriad”) are entering into, and effecting a closing under, an Asset Purchase Agreement and related agreements whereby Panacos is assigning to Myriad Panacos’s share of the ownership interest in certain inventions covered by certain Patents (not including the Inventions) jointly owned by Panacos and University (the “Bevirimat Patents”), and (ii) University and Myriad are entering into a License Agreement dated as of the date hereof whereby University is granting to Myriad a worldwide license to the Bevirimat Patents; and

WHEREAS, Licensee is desirous of producing, using and selling products which include the use of Inventions and is willing to expend its commercially reasonable efforts and resources to do so if it can obtain an exclusive license to use the Inventions under the terms and conditions set forth herein; and

WHEREAS, University and Niigata desire to facilitate a timely transfer of their information and technology concerning the Inventions for the ultimate benefit of the public and this transfer is best accomplished by the grant of this license; and

WHEREAS, in the opinion of the University and Niigata, this transfer can best be accomplished consistent with their mission by affiliation with Licensee;

WHEREAS, University, Niigata, and Licensee entered into that certain License Agreement dated as of February 28, 2003 (as amended) pursuant to which Licensee obtained an exclusive license to certain Inventions (the “ Original Agreement ”);

WHEREAS, University, Niigata, and Licensee now wish to amend and restate the Original Agreement in its entirety;

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NOW, THEREFORE, for and in consideration of the covenants, conditions, and undertakings hereinafter set forth, it is agreed by and between the parties as follows:

I. DEFINITIONS

1.1. “U NIVERSITY T ECHNOLOGY ” means any unpublished (a) research and development information, (b) unpatented inventions, and (c) technical data, owned by or in the control of University prior to the Effective Date or during the Term of this Agreement, which relates to and is necessary for: (i) the practice of the Inventions, or (ii) the manufacture, use, sale, offer for sale or importation of any compounds disclosed in the Patents or any analogs, derivatives, modifications or improvements thereof, and which University has the right to provide Licensee under this Agreement, and which Licensee does not otherwise own or control.

1.2. “I NVENTIONS ” has the meaning set forth in the first Whereas clause above.

1.3. “N IIGATA I NVENTIONS ” has the meaning set forth in the first Whereas clause above.

1.4. “U NIVERSITY I NVENTIONS ” has the meaning set forth in the first Whereas clause above.

1.5. “L ICENSED P RODUCTS ” means (i) any method, procedure, or component part thereof whose manufacture, use, sale, offer for sale or importation is covered by any University Technology or Niigata Technology or by one or more Valid Claims of the Patents, or (ii) any product containing at least one Licensed Compound.

1.6. “L ICENSED C OMPOUNDS ” means any individual compounds whose manufacture, use, sale, offer for sale or importation is covered by any University Technology or Niigata Technology or by one or more Valid Claims of the Patents.

1.7. “P ATENTS ” means any US patents and/or patent applications owned or controlled in whole or in part by University or Niigata prior to or during the Term of this Agreement and which University and/or Niigata has the right to provide its share to Licensee and which are included in and limited to those listed in Appendix A and Appendix B, as well as any continuations, continuations in part, divisionals, provisionals, continued prosecution applications, extensions, or reissues thereof, and any foreign counterpart of any of the foregoing.

1.8. “N ET S ALES ” means, subject to Article 3.4, the invoiced sales price of Licensed Products sold by Licensee, less (a) any charges for sales taxes or other taxes separately stated on the invoice, (b) shipping and insurance charges, (c) actual credits and allowances for returned, rejected, recalled, or defective goods, (d) trade discounts, but before cash discounts and (e) government mandated rebates. Licensed Products will be considered sold when billed out, or when delivered or paid for before delivery, whichever first occurs. As used herein, “cash discounts” means discounts given on account of payments made in cash or payments made early.

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1.9. “L ICENSED T ERRITORY ” means the world, subject to any restrictions in Article XI herein.

1.10. “L ICENSED F IELD ” means any and all human therapeutic and prophylactic uses.

1.11. “S UBLICENSEE ” means any person or organization to which Licensee has granted a sublicense to the University Technology or Niigata Technology or Patents for the purpose of development and/or commercialization of Licensed Products in the Licensed Field.

1.12. “C ONFIDENTIAL I NFORMATION ” means information considered proprietary to the party disclosing the information, and may include information relating to: research, development, patent prosecution and maintenance, manufacturing, purchasing, accounting, engineering, marketing, merchandising or selling.

1.13. “S UBLICENSE I NCOME ” means all royalties, all other payments, and any equity Licensee receives from Sublicensees, of which University and/or Niigata is owed a percentage; provided, however, that Sublicense Income shall specifically exclude (i) payments made in consideration for the issuance of equity or debt securities of Licensee at fair market value (but shall specifically include any payments received by Licensee from the issuance of securities of Licensee to the extent such payments are in excess of fair market value), (ii) equity or debt securities of a Sublicensee issued to Licensee if acquired by Licensee at fair market value, and (iii) payments specifically committed to research funding or development activities, or reimbursements of the same. In the event of a sublicense as contemplated herein, such sublicense shall state explicitly the consideration provided in exchange for University Technology or Niigata Technology or Patents.

1.14. “IND” means an Investigational New Drug Application filed with the Food and Drug Administration for authorization to initiate human clinical trials in the United States, or any foreign equivalent document for authorization to initiate human clinical trials outside the United States.

1.15. “A FFILIATE ” means any corporation or other business entity which, directly or indirectly, controls, is controlled by, or is under common control with, a party. For purposes of this definition, “control” means ownership or beneficial interest in 40% or more of the voting stock or other voting interest of the corporation or other business entity.

1.16. “ ANDA ” means an Abbreviated New Drug Application, made in the form of a Food and Drug Administration submission or package to the Food and Drug Administration, for approval to market a Licensed Product in the United States, or any foreign equivalent document for approval to market a Licensed Product outside the United States.

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1.17. “ CLASS OF LICENSED COMPOUNDS ” means each subset of Licensed Compounds as described in the Patents and identified in Appendix A and Appendix B as (i) Class 1, (ii) Class 2, or (iii) Class 3.

1.18. “ FIRST COMMERCIAL SALE ” means the first sale of Licensed Product for use in the Field by Licensee or its Sublicensee to any third party in a country.

1.19. “ NDA ” means an original New Drug Application, made in the form of a Food and Drug Administration submission or package to the Food and Drug Administration, for approval to market a Licensed Product in the United States, or any foreign equivalent document.

1.20. “P ERFORMANCE M ILESTONE ” means any milestone listed on Appendix C attached hereto.

1.21. “P HASE II C LINICAL T RIAL ” means a dosing range trial to evaluate efficacy and safety in the targeted patient population and/or to define optimal dosing regimen of Licensed Product, or any other trial required to be designated as a Phase II clinical trial by the Food and Drug Administration.

1.22. “R OYALTY Q UARTER ” has the meaning set forth in Article 3.5.

1.23. “S PONSORED R ESEARCH A GREEMENT ” means that certain sponsored research agreement by and between University and Licensee effective April 28, 1999, including any amendments thereto.

1.24. “T ERM ” shall commence on the Effective Date and shall expire upon the expiration of the last Valid Claim of the Patents, unless earlier terminated pursuant to Article VII.

1.25. “V ALID C LAIM ” means either (a) a claim of an issued and unexpired patent included within the Patents which has not been held permanently revoked, unenforceable or invalid by a decision of a court or other governmental agency of competent jurisdiction, unappealable or unappealed within the time allowed for appeal, and which has not been admitted to be invalid or unenforceable through reissue or disclaimer or otherwise or (b) a claim of a pending patent application included within the Patents, which claim was filed in good faith and has not been abandoned or finally disallowed without the possibility of appeal or refiling of said application. Notwithstanding the foregoing (and subject to Article 3.3(iii)), if a claim of a pending patent application has not issued as a claim of an issued patent within ten (10) years after the filing date from which such claim takes priority, such pending claim shall cease to be a Valid Claim for purposes of this Agreement unless and until such claim becomes an issued claim of an issued patent.

1.26. “P ATENT C OUNSEL ” has the meaning set forth in Article 11.1.

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1.27. “N IIGATA T ECHNOLOGY ” means any unpublished (a) research and development information, (b) unpatented inventions, and (c) technical data, owned by or in the control of Niigata prior to the Effective Date or thereafter during the Term, which relates to and is necessary for: (i) the practice of the Niigata Inventions, or (ii) the manufacture, use, sale, offer for sale or importation of any compounds disclosed in the Niigata Patents or any analogs, derivatives, modifications or improvements thereof, and which Niigata has the right to provide Licensee under this Agreement, and which Licensee does not otherwise own or control.

II. TERMINATION OF ORIGINAL AGREEMENT; GRANT OF LICENSE; UNIVERSITY RESTRICTIONS

2.1. University, Niigata, and Licensee hereby acknowledge and agree that the Original Agreement is terminated and superseded by this Agreement as of the Effective Date of this Agreement. Notwithstanding any provision to the contrary in the Original Agreement, no provision contained therein shall survive termination of the Original Agreement. Notwithstanding the foregoing, each party hereby agrees that all actions, suits, damages, claims and demands, in law or in equity, which either of them has against the other under the terms of the Original Agreement, upon, or by reason of any breach of the Original Agreement, shall be enforceable under this Agreement.

2.2. (i) University grants to Licensee, to the extent of the Licensed Territory, a non-exclusive right and license (with the right to grant sublicenses pursuant to Article 2.3) to use University Technology in the Licensed Field, subject to all the terms and conditions of this Agreement.

(ii) University grants to Licensee, to the extent of the Licensed Territory, an exclusive right and license (with the right to grant sublicenses pursuant to Article 2.3) under the Patents to make, have made, use, sell, offer for sale, and import Licensed Products and Licensed Compounds embodying the Invention(s) in the Licensed Field, upon the terms and conditions set forth herein.

(iii) Niigata grants to Licensee, to the extent of the Licensed Territory, a non-exclusive right and license (with the right to grant sublicenses pursuant to Article 2.3) to use Niigata Technology in the Licensed Field, subject to all the terms and conditions of this Agreement.

(iv) Niigata grants to Licensee, to the extent of the Licensed Territory, an exclusive right and license (with the right to grant sublicenses pursuant to Article 2.3) under the Niigata Patents to make, have made, use, sell, offer for sale, and import Licensed Products and Licensed Compounds embodying the Niigata Inventions in the Licensed Field, upon the terms and conditions set forth herein.

2.3. University and Niigata each grant to Licensee, to the extent of the Licensed Territory, the right to sublicense. Sublicensees shall be subject to provisions substantially similar to the following provisions of this Agreement: Articles 2.5, 2.6, 2.7, 2.8, 2.9, VI, IX, 11.6, XIV, XV, XVI, XIX, XXI, and XXII and this Article 2.3. Sublicensees may not further sublicense

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any rights they obtain herein without the written consent of University as to the University Inventions and Niigata as to the Niigata Inventions. In the event of early termination of this Agreement, any sublicense agreement with any Sublicensee shall provide for the termination of the sublicense, or the conversion to a license directly between such Sublicensee and University and/or Niigata (as the case may be) on substantially the same terms as the sublicense agreement, at the option of the Sublicensee, provided, however, that in no event shall University or Niigata have greater obligations to such Sublicensee as it has to Licensee hereunder.

2.4. Any license granted herein (excluding the grant in Article 2.2(i) above) is exclusive for the Term of this Agreement.

2.5. Licensee shall not disclose any University Technology pursuant to Article 2.2(i) above to third parties during the Term or any time thereafter, provided, however, that disclosure of University Technology may be made at any time (1) with the prior written consent of University, or (2) pursuant to the provisions of this Agreement, including Article 6 herein.

2.6. Licensee shall not disclose any Niigata Technology pursuant to Article 2.2(iii) above to third parties during the Term or any time thereafter, provided, however, that disclosure of Niigata Technology may be made at any time (1) with the prior written consent of Niigata, or (2) pursuant to the provisions of this Agreement, including Article 6 herein.

2.7. Licensee is further granted the right to disclose and use any University Technology, or other Confidential Information of University or Niigata Technology, or other Confidential Information of Niigata pertaining to the Patents, Licensed Products, or Licensed Compounds in any submission to local, state, federal or foreign governmental agency, including, but not limited to, the US Food and Drug Administration and the US Patent and Trademark Office, notwithstanding any provisions to the contrary in Article VI.

2.8. Notwithstanding the foregoing, any and all licenses granted hereunder are subject to the rights of the United States Government which may arise out of its sponsorship of the research which led to the Inventions.

2.9. Subject to the licenses granted to Licensee pursuant to the foregoing provisions of this Article II, each party retains all right, title, and interest in such party’s inventions and intellectual property, including, without limitation, its share of any joint inventions and jointly owned Patents.

III. LICENSE FEE AND ROYALTIES

3.1. [RESERVED].

3.2. The parties acknowledge that Licensee has paid University for all past costs (including reasonable attorney’s fees) arising out of the filing, prosecution, or maintenance of the Patents. Licensee will pay a further license fee in the form of

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payment of future costs (including attorney’s fees) arising out of the filing and prosecution of the Patents covering the Inventions pursuant to Article XI of this Agreement. Payment of such costs shall be non-refundable and shall not be a credit against any other amounts due hereunder.

3.3. (i) Beginning on the Effective Date of this Agreement and continuing, on a country-by-country basis, until the last to expire Valid Claim of Patents covering such Licensed Products, Licensee will pay University a running patent royalty on all Net Sales of Licensed Products in the Licensed Field covered by a Valid Claim of the Patents, in accordance with the chart below:

Notwithstanding the foregoing provisions of this Article 3.3(i), (a) in the event that the Licensed Product for which royalties are payable hereunder is covered by a Valid Claim of the Niigata Patents but no other Patents, then Licensee shall pay University one-half (  ¹ / 2 ) of the royalties otherwise payable to University under this Article 3.3(i), and Licensee shall pay Niigata the remaining one-half (  ¹ / 2 ) of such royalties; and (b) in the event that the Licensed Product for which royalties are payable hereunder is covered by Valid Claims of both the Niigata Patents and at least one other Patent, then Licensee shall pay University two-third (  ² / 3 ) of the royalties otherwise payable to University under this Article 3.3(i), and Licensee shall pay Niigata the remaining one-third (  ¹ / 3 ) of such royalties.

(ii) During the Term of this Agreement, Licensee will pay University a running technology royalty on all Net Sales of Licensed Products in the Licensed Field not covered by a Valid Claim of the Patents but whose manufacture, use, sale, offer for sale or importation is covered by University Technology, in accordance with the chart below:

Notwithstanding the foregoing provisions of this Article 3.3(ii), (a) in the event that the Licensed Product for which royalties are payable hereunder is covered by both University Technology and Niigata Technology, then Licensee shall pay University

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one-half (  ¹ / 2 ) of the royalties otherwise payable to University under this Article 3.3(ii), and Licensee shall pay Niigata the remaining one-half (  ¹ / 2 ) of such royalties; and (b) in the event that the Licensed Product for which royalties are payable hereunder is not covered by University Technology but is covered by Niigata Technology, then Licensee shall pay Niigata one hundred percent (100%) of the royalties otherwise payable to University under this Article 3.3(ii).

(iii) In addition to the foregoing, the parties acknowledge and agree that in the event a claim of a pending patent application ceases to be a Valid Claim pursuant to the last sentence of Article 1.23, and such pending patent application later issues during the Term of this Agreement, Licensee shall pay University and/or Niigata the difference between any patent royalties that would have been payable by Licensee under Article 3.3(i) if such claim of the pending patent application had not ceased to be a Valid Claim in the first instance pursuant to Article 1.23, and the technology royalty actually paid pursuant to Article 3.3(ii).

(iv) No later than thirty (30) days before the First Commercial Sale of a particular Licensed Product, Licensee retains the right to notify University and Niigata in writing of its determination of the allocation of payments between University and Niigata hereunder (if any). In such an event, University and Niigata shall have thirty (30) days to respond in writing if they disagree with Licensee’s determination. In the event Licensee does not receive written notice of a disagreement within such 30 day period, then Licensee’s determination shall be deemed acceptable to the parties. In the event Licensee receives written notice of a disagreement within such 30 day period, Licensee retains the right to make royalty payments into an escrow account until such time as University and Niigata provide Licensee with written confirmation of their resolution of such disagreement. In no event shall Licensee owe University and Niigata, in the aggregate, royalties greater than the royalty rates set forth in this Article 3.3.

3.4. (i) In the event any Licensed Product in the Licensed Field is a combination of one or more Licensed Compounds with one or more other active ingredients not licensed hereunder, Net Sales for purposes of determining royalty payments on such combination shall be calculated by multiplying the net sales (i.e., the invoiced sales price of the combination less the deductions set forth in Article 1.6) by the fraction A/(A+B) in which “A” is the total of the gross selling prices of the Licensed Compounds, and “B” is the total of the gross selling prices of the other active ingredients.

(ii) In the event that it is not possible to determine the gross selling price for each ingredient, Net Sales shall be calculated by multiplying the net sales (i.e., the invoiced sales price of the combination less the deductions set forth in Article 1.6) of the combination by the fraction C/(C+D), in which “C” is the total of the direct costs plus the direct overhead of the Licensed Compounds and “D” that of the other active ingredients. The direct costs plus the direct overhead of a component shall be determined in accordance with generally acceptable cost accounting principles.

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3.5. Beginning with the date of First Commercial Sale of any Licensed Product in the Licensed Field, Licensee agrees to make quarterly written reports to University and Niigata (with respect to Licensed Products covered by a Valid Claim of the Niigata Patents or by Niigata Technology) within thirty (30) days after the first (1st) days of each January, April, July, and October during the Term of this Agreement and as of such dates, stating in each such report the number, description, and aggregate Net Sales of Licensed Products sold, used, or otherwise disposed of during the preceding three calendar months (each such three calendar months a “Royalty Quarter”) and upon which a royalty or percentage of Sublicense Income is payable as provided in Articles 3.3 or IV hereof, as appropriate. The first such report shall include all Net Sales of Licensed Products made prior to the date of such report. Until Licensee has achieved the First Commercial Sale of Licensed Product, a report shall be submitted by Licensee at the end of each January after the Effective Date of this Agreement and will include a full written report summarizing Licensee’s technical and other efforts made towards such First Commercial Sale of a Licensed Product.

3.6. In the event that it is necessary or required for Licensee to make royalty or other payments to one or more third parties in order for Licensee or any Sublicensee to make, use, or sell Licensed Products, Licensee may offset a total of fifty percent (50%) of such third-party payments against any royalty payments and/or percentage of Sublicense Income, as appropriate and in the Royalty Quarter they are due, that are otherwise due University and/or Niigata hereunder, provided that in no event shall the royalty payments or percentage of Sublicense Income otherwise due University and/or Niigata be reduced by more than fifty percent (50%) in any Royalty Quarter. Notwithstanding the foregoing, in no event shall Licensee offset third-party payments against any royalty payments and/or percentage of Sublicense Income that are otherwise due University and/or Niigata hereunder if such third party payments relate solely to other active ingredients to which the combination Product calculations in Article 3.4 have been applied.

3.7. Concurrently with the making of each report pursuant to Article 3.5 above, Licensee shall pay to the University and/or Niigata all payments due University and/or Niigata under Articles 3.3, 3.8 or IV, as appropriate.

3.8. Licensee will make milestone payments upon the first of either Licensee or a Sublicensee reaching the designated stages of development listed in the table below, for each Licensed Product. Payment shall be the greater of the compensation due University pursuant to Article IV (if applicable), or the amount listed in the table below.

Notwithstanding the foregoing, (a) in the event that the Licensed Product for which milestone payments are due hereunder is covered by a Valid Claim of the Niigata Patents but no other Patents, or is not covered by a Valid Claim of any Patents but is covered by the University Technology and Niigata Technology, then Licensee shall pay University one-half (  ¹ / 2 ) of the compensation otherwise payable to University under this Article 3.8 (or Article IV as the case may be), and Licensee shall pay Niigata the remaining one-half (  ¹ / 2 ) of such compensation; and (b) in the event that the Licensed Product for which milestone payments are due hereunder is covered by Valid Claims of both the Niigata Patents and at least one other Patent, then Licensee shall pay University two-thirds (  ² / 3 ) of the compensation otherwise payable to University under this Article 3.8 (or Article IV as

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the case may be), and Licensee shall pay Niigata the remaining one-third (  ¹ / 3 ) of such compensation; and (c) in the event that the Licensed Product for which milestone payments are due hereunder is not covered by a Valid Claim of any Patents but is covered by the Niigata Technology but not the University Technology, then Licensee shall pay Niigata one hundred percent (100%) of the compensation otherwise payable to Uni