LICENSE AGREEMENT DATED APRIL 17, 2006

Exhibit 10.15

Portions of this exhibit marked [*] are requested to be treated confidentially.

LICENSE AGREEMENT

17 ^th  August 2006

THIS LICENSE AGREEMENT (this “Agreement”) dated as of August 17 ^th , 2006 (the “Effective Date”) is entered into between KTB Tumorforschungs GmbH (Tumor Biology Center), a privately-held corporation (“Licensor”), having a place of business at Breisacher Str. 117, Freiburg, Germany, and Innovive Pharmaceuticals, Inc. a corporation with principal offices located at 555 Madison Avenue, New York, New York 10022 (“Company”).

WHEREAS, Licensor owns or has rights in the Technology (as defined below).

WHEREAS, Company desires to obtain an exclusive license under Licensor’s rights in the Technology on the terms and conditions set forth below.

NOW, THEREFORE, in consideration of the foregoing premises and the mutual covenants herein contained, the parties hereby agree as follows:

1. DEFINITIONS

For purposes of this Agreement, the terms defined in this Section 1 shall have the respective meanings set forth below:

1.1 “ Affiliate ” shall mean, with respect to any Person, any other Person which directly or indirectly controls, is controlled by, or is under common control with, such Person. A Person shall be regarded as in control of another Person if it owns, or directly or indirectly controls, at least fifty percent (50%) of the voting stock or other ownership interest of the other Person, or if it directly or indirectly possesses the power to direct or cause the direction of the management and policies of the other Person by any means whatsoever.

1.2 “ Competent Authority(ies) ” shall mean, collectively, the governmental entities in each country in the Territory responsible for (a) the regulation of any Product intended for use in the Field, including the FDA, the EMEA and the MHLW, (b) the establishment, maintenance and/or protection of rights related to the Licensed Patent Rights, or (c) any other applicable regulatory or administrative agency in any country in the Territory that is comparable to, or a counterpart of, the foregoing.

1.3 “ Field ” shall mean all fields of use.

1.4 “ First Commercial Sale ” shall mean, with respect to any Product, the first sale of such Product after all applicable marketing and pricing approvals (if any) have been granted by the Competent Authority.

1.5 “ Licensed IP Rights ” shall mean, collectively, the Licensed Patent Rights and the Licensed Know-How Rights.

1.6 “ Licensed Know-How Rights ” shall mean all trade secret and other know-how rights in and to all data, information, compositions and other technology (including, but not limited to, formulae, procedures, protocols, techniques and results of experimentation and testing) that are not Licensed Patent Rights and which are necessary or useful for Company to make, use, develop, sell or seek regulatory approval to market a composition, or to practice any method or process, at any time claimed or disclosed in any issued patent or pending patent application within the Licensed Patent Rights or which otherwise relates to the Technology, where such licensed-know how rights are owned by Licensor or Licensor has the right to grant a sublicense for.

1.7 “ Licensed Patent Rights ” shall mean (a) the patents and patent applications listed on Exhibit A hereto, and all worldwide counterparts thereof in which Licensor has an ownership or the right to grant a sublicense for, to the extent they claim or disclose the Technology, (b) all U.S. and foreign patents and patent applications that claim or cover the Technology in which Licensor heretofore or hereafter has an ownership or (sub)licensable interest, (c) all divisions, continuations, continuations-in-part, that claim priority to, or common priority with, the patent applications listed in clauses (a)—(b) above or the patent applications that resulted in the patents described in clauses (a)—(b) above which Licensor owns or has the right to grant a sublicense for, and (d) all patents that have issued or in the future issue from any of the foregoing patent applications, including utility, model and design patents and certificates of invention, together with any reissues, renewals, extensions or additions thereto, which are owned by Licensor or Licensor has the right to grant a sublicense for.

1.8 “ Net Sales ” shall mean, with respect to any Product, the gross sales price of such Product invoiced by Company or its Affiliate or sublicensees to customers who are not Affiliates (or are Affiliates but are the end users of such Product) less, to the extent actually paid or accrued by Company or its Affiliate or sublicensees (as applicable), (a) credits, allowances, discounts and rebates to, and chargebacks from the account of, such customers for spoiled, damaged, out-dated and returned Product, provided however , Licensor’s consent shall be required for any discount above [*] ([*]%) or any transfer on a non-cash-basis (except transfers for research or development purposes, clinical trials, compassionate use purposes or as samples or promotions) in order for such discount or transfer to be excluded from the calculation of Net Sales ; (b) freight and insurance costs incurred by Company or its Affiliate or sublicensees (as applicable) in transporting such Product to such customers; (c) cash, quantity and trade discounts, rebates and other price reductions for such Product given to such customers under price reduction programs; (d) sales, use, value-added and other taxes (excluding income taxes and other taxes on profit and property) incurred on the sale of such Product to such customers; and (e) customs duties, surcharges and other governmental charges incurred in exporting or importing such Product to such customers.

1.9 “ Non-Royalty Sublicensing Income ” shall mean, with respect to any Product, the aggregate cash consideration directly received by Company or its Affiliates in consideration for the Company or its Affiliates entry into a sublicense agreement under the Licensed IP Rights with a Third Party sublicensee with respect to such Product, but excluding (a) Royalty Sublicensing Revenues, (b) amounts received to reimburse Company or its Affiliates’ cost to perform research, development or similar services, (c) amounts received in reimbursement of patent or other out-of-pocket expenses, and (d) amounts received in

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consideration for the purchase of any securities of Company or its Affiliates at fair market value. Notwithstanding the foregoing, if a Third Party purchases securities in any Affiliate, and the purchase price is inter alia determined by the (direct or indirect) receipt of a sublicense under the Licensed IP Rights (e.g. a sublicense hold by the purchased Affiliate) or to Products (unless such premium is paid to reimburse Company or its Affiliates’ cost to perform research, development or similar services related to the Technology or Product development) then the respective portion of the purchase price shall be included within Non-Royalty Sublicensing Income. The same shall apply if a Third Party purchases securities in Company and a premium above the fair market value is paid for the (direct or indirect) receipt of a sublicense under the Licensed IP Rights or to Products (unless such premium is paid to reimburse Affiliates’ cost to perform research, development or similar services related to the Technology or Product development).

1.10 “ Oncology Field ” shall mean the detection, diagnosis, prognosis, monitoring, prevention or treatment of any oncologic disease, state or condition in humans or animals.

1.11 “ Optional Technology ” shall mean all methods, compositions, uses, technology, data and information that is claimed or disclosed in the patents and patent applications listed on Exhibit A hereto (as may be amended from time to time by the parties), or any modifications or derivatives thereto, in each case to the extent having application in the Oncology Field.

1.12 “ Person ” shall mean an individual, corporation, partnership, limited liability company, trust, business trust, association, joint stock company, joint venture, pool, syndicate, sole proprietorship, unincorporated organization, governmental authority or any other form of entity not specifically listed herein.

1.13 “ Product(s) ” shall mean any product for use in the Field that if made, used, sold, offered for sale or imported absent the license granted hereunder would infringe a Valid Claim, or that otherwise uses or incorporates the Licensed IP Rights.

1.14 “ Registration(s) ” shall mean any and all permits, licenses, authorizations, registrations or regulatory approvals (including NDAs) required and/or granted by any Competent Authority as a prerequisite to the development, manufacturing, packaging, marketing and selling of any product.

1.15 “ Royalty Sublicensing Revenues ” shall mean, with respect to any Product, the aggregate royalty cash consideration, received by Company or its Affiliates directly in consideration for the sublicense under the Licensed IP Rights by Company or its Affiliates to a Third Party sublicensee with respect to such Product, that is based on sales of such Product by or on behalf of such sublicensee.

1.16 “ Royalty Term ” shall mean, with respect to each Product in each country, the term for which a Valid Claim remains in effect that, if granted or issued, would be infringed but for the license granted by this Agreement, by the use, offer for sale, sale or import of such Product in such country.

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1.17 “ Technology ” shall mean (a) all methods, compositions, uses, technology, data and information relating to any anthracycline derivates with an acid-sensitive linkers, and (b) if Company has exercised its option under Section 3.6, the Optional Technology (including the applicable Mentioned Optional Technology).

1.18 “ Territory ” shall mean the world.

1.19 “ Third Party ” shall mean any Person other than Licensor, Company and their respective Affiliates.

1.20 “ Valid Claim ” shall mean (a) claim of an issued or granted and unexpired patent included within the Licensed Patent Rights, 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 Licensed Patent Rights, which claim was filed in good faith, has not been pending for more than seven (7) years and has not been abandoned or finally disallowed without the possibility of appeal or refiling of such application. Any claim that has been pending for more than seven (7) years and which is thereafter issued or granted becomes a Valid Claim under (a) at its issue or grant date.

2. REPRESENTATIONS AND WARRANTIES

Each party hereby represents and warrants to the other party as follows:

2.1 Corporate Existence . Such party is a corporation duly organized, validly existing and in good standing under the laws of the state in which it is incorporated.

2.2 Authorization and Enforcement of Obligations . Such party (a) has the corporate power and authority and the legal right to enter into this Agreement and to perform its obligations hereunder, and (b) has taken all necessary corporate action on its part to authorize the execution and delivery of this Agreement and the performance of its obligations hereunder. This Agreement has been duly executed and delivered on behalf of such party, and constitutes a legal, valid, binding obligation, enforceable against such party in accordance with its terms.

2.3 No Consents . All necessary consents, approvals and authorizations of all governmental authorities and other Persons required to be obtained by such party in connection with this Agreement have been obtained.

2.4 No Conflict . The execution and delivery of this Agreement and the performance of such party’s obligations hereunder (a) do not conflict with or violate any requirement of applicable laws or regulations, and (b) do not conflict with, or constitute a default under, any contractual obligation of it.

2.5 Licensed IP Rights . To the best of Licensor’s knowledge Licensor (a) is the sole owner or exclusive licensee of the Licensed IP Rights, and except as Licensor has expressly informed Company in writing prior to the date of this Agreement, has not granted to any Third Party any license or other interest in the Licensed IP Rights, (b) is not aware of any

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Third Party patent, patent application or other intellectual property rights that would be infringed (i) by practicing any process or method or by making, using or selling any composition which is claimed or disclosed in the Licensed Patent Rights or which constitutes Licensed Know-How Rights, or (ii) by making, using or selling Products, and (c) is not aware of any infringement or misappropriation by a Third Party of the Licensed IP Rights. The Company is aware of the patents US 5,622,929, US 824,951, US 5,606,017 and EP 554 708 B1.

3. LICENSE GRANT

3.1 Licensed IP Rights . Licensor hereby grants to Company an exclusive license (with the right to grant sublicenses through multiple tiers) under the Licensed IP Rights to conduct research and to develop, make, have made, use, offer for sale, sell and import Product in the Territory for use in the Field.

3.2 Availability of the Licensed IP Rights . Licensor shall provide Company with a copy of all information available to Licensor relating to the Licensed IP Rights, Products or Technology, including without limitation: (a) regulatory submissions, (b) communications with the Competent Authorities (including the minutes of any meetings), (c) trial master files, including case report forms, (d) listings and tables of results from the clinical trials, (e) treatment-related serious adverse event reports from the clinical trials, (f) storage of and access permission to any retained samples of materials used in clinical trials, and (g) access to CROs involved in the clinical trials.

3.3 Registrations . Licensor acknowledges and agrees that Company shall own all Registrations for Products for use in the Field in each country in the Territory. Licensor hereby grants to Company a free-of-charge right to reference and use and have full access to all other Registrations and all other regulatory documents that relate to the Licensed IP Rights, Products or Technology, including INDs, BLAs, NDAs and DMFs (whether as an independent document or as part of any NDA, and all chemistry, manufacturing and controls information), and any supplements, amendments or updates to the foregoing (for the purposes of this Section, the “Right of Reference”). Company shall have the right to (sub)license the Right of Reference to its sublicensees and Affiliates. Licensor shall promptly notify Company of any written or oral notices received from, or inspections by any Competent Authority relating to any such Registrations, and shall promptly inform Company of any responses to such written notices or inspections and the resolution of any issue raised by such Competent Authority. During the time that Licensor is the holder of a Registration, Company shall be entitled to attend any and all meetings and participate in telephone calls with the Competent Authorities, including without limitation any meeting preparation, meeting co-ordination and preparation of minutes.

3.4 Access to Manufacturers . Licensor shall use its commercially reasonable efforts to provide access to Company to any suppliers of the API form of any Product for use in the Field on terms and conditions no less favorable than those terms and conditions between Licensor and such supplier.

3.5 Sublicense . Company may grant sublicenses in multiple tiers in its sole discretion. The Company shall provide Licensor with copies of all sublicense agreement within thirty (30) days of their execution date. Company shall have the right to redact any confidential

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information in such copies of sublicense agreements that does not relate to either the Licensed IP Rights hereunder or the economic terms therein. Each sublicense agreement shall contain covenants by the sublicensee for such sublicensee to observe and perform the same terms and conditions as those set forth for the Company in this Agreement. The Company shall be responsible for curing the acts or omissions of its sublicensees and shall not grant any rights which are inconsistent with the rights granted to and obligations of the Company hereunder. All sublicenses shall survive termination of this Agreement provided such sublicensees are not in breach (taking into account any applicable cure period provided in such sublicense); and, provided further that Licensor shall not be obligated to incur any obligation or duties to any sublicensee of the Company not otherwise provided for in this Agreement.

3.6 Optional Technology .

3.6.1 Option . Company shall have the right and option to include Optional Technology within the license grant set forth in Section 3.1 above for use in the Oncology Field. Such right and option may be exercised at any time by Company sending to Licensor written notice of such exercise, with respect to each different combination of an anti-neoplastic agent and a linker the option is exercised for (“Mentioned Optional Technology”). Each exercise of this option causes the obligation of Company to pay additional Milestones in accordance with Section 4.2 of this Agreement, including a license issue fee in accordance with Section 4.2 (a). Upon exercise of such right and option, the Mentioned Optional Technology shall be included within the definition of Technology and shall be included within the license grant set forth in Section 3.1 for use within the Oncology Field. The same terms and conditions as stipulated in this Agreement for the license of Technology apply for the Mentioned Optional Technology as well, especially, but not limited to, the obligation of Company to pay Royalties for the license of Mentioned Optional Technology in accordance with Section 4.1 of this Agreement.

3.6.2 Right of first refusal : If Licensor desires to grant to any Third Party a license or other right to any intellectual property rights covering Optional Technology in the Oncology Field, Licensor shall give to Company express written notice thereof, together with (i) copies of all data and information in its or its Affiliates’ possession regarding applications of the Optional Technology within the Oncology Field, or (ii) the terms and conditions of an intended license agreement with a Third Party (“Third Party Agreement”). If Company fails to exercise in case (i) its right under Section 3.6.1 within [*] ([*]) days after the receipt of such notice, data and information, and in case (ii) its hereby granted right of first refusal within [*] ([*]) days after the receipt of such notice and the intended Third Party Agreement, then Licensor shall have the right to enter into a binding Third Party Agreement granting such license or other right to such Third Party within another [*] ([*]) days. Licensor shall not grant such license or other right to such Third Party on terms and conditions that are more favorable to such Third Party than in case (i) the terms and conditions of this Agreement, and in case (ii) the disclosed terms and conditions of the intended Third Party Agreement unless Licensor first offers in writing to Company such more favorable terms and conditions and Company fails to accept such offer within [*] ([*]) days after written notice of such more favorable offer. Company may not exercise its right under Section 3.6.1 from receipt of the notice of the intended Third Party Agreement (case (ii)) on, until the end of the period, Licensor may enter into a binding Third Party Agreement.

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4. FINANCIAL CONSIDERATIONS

4.1 Royalties .

4.1.1 Royalty Rate . In consideration for the licenses granted to Company herein, during the Royalty Term for a Product, Company shall pay to Licensor royalties, with respect to each Product, equal to (a) [*] percent ([*]%) of Net Sales of such Product by Company and its Affiliates of up to [*] Dollars in any calendar year, [*] percent ([*]%) of Net Sales of such Product by Company and its Affiliates in excess of [*] Dollars but less then [*] Dollars in any calendar year, and [*] percent ([*]%) of Net Sales of such Product by Company and its Affiliates of greater than [*] Dollars in any calendar year, (b) the greater of (i) [*] percent ([*]%) of Royalty Sublicensing Revenues, or (ii) [*] percent ([*]%) of Net Sales of such Product by such sublicensee, and (c) [*] percent ([*]%) of all Non-Royalty Sublicensing Income received by Company and its Affiliates. Only one royalty shall be owing for a Product regardless of how many Valid Claims cover such Product.

4.1.2 Third Party Royalties . If Company or its Affiliates is required to pay royalties to any Third Party in order to exercise its rights hereunder to make, have made, use, sell, offer to sale or import any Product, then Company shall have the right to credit against the royalties owing to Licensor under Section 4.1.1 above with respect to sales of such Product in such country: (a) [*] percent ([*]%) of such Third Party royalty payments made to Bristol-Myers Squibb Company (“BMS”) for any of the patents (or patents from the same patent family) identified in the last sentence of Section 2.5, and (b) [*] percent ([*]%) of all other such Third Party royalty payments. Company shall keep Licensor involved in any discussions with BMS for a license to such patents. Company shall have the right to credit any such Third Party royalties paid by a sublicensee against the royalties owing to Licensor in accordance with the foregoing, to the extent such Third Party royalties are deducted from the applicable Royalty Sublicensing Revenue paid by such sublicensee. Notwithstanding the foregoing, Company shall not reduce the amount of the royalties paid to Licensor under Section 4.1.1 above by reason of this Section 4.1.2, with respect to sales of such Product in such country, to less than [*] percent ([*]%) of Net Sales of such Product in such country.

4.2 Milestones . Company shall pay to Licensor the following milestone payments within [*] ([*]) days following the first achievement of the applicable milestone:

(a) A license issue fee of Five Hundred Thousand U.S. dollars (U.S. $ 500,000.00), payable within thirty (30) days of execution of this Agreement;

(b) [*] US dollars (U.S. $[*]) upon first dosing of a patient in a first Phase II clinical trial under Company-sponsored (or Affiliate-sponsored, or sublicensee-sponsored) Investigative New Drug Application (“IND”) for a Product;

(c) [*] US dollars (U.S. $[*]) upon conclusion of an End-of-Phase II Meeting with respect to a Product as defined by 21 CFR 312.47(b) or compareable regulation with a Competent Authority;

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(d) [*] US dollars (U.S. $[*]) upon first dosing of a patient in the first Phase III clinical trial under