system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
"""
Exhibit 10.5 Certain identified information has been excluded because it is both not material and would likely cause competitive harm if publicly disclosed. COMMERCIALIZATION AND LICENSE AGREEMENT This Commercialization and License Agreement (this "Agreement") is made effective as of December 17, 2019 (the "Effective Date") by and between Vyera Pharmaceuticals, LLC, a Delaware limited liability company ("Vyera"), and CytoDyn Inc., a Delaware corporation ("CytoDyn"). CytoDyn and Vyera are sometimes referred to herein individually as a "Party" and collectively as the "Parties." RECITALS WHEREAS, Vyera is a pharmaceutical company engaged in the commercialization of products useful in the amelioration, treatment or prevention of certain human diseases and conditions. WHEREAS, CytoDyn has developed leronlimab (PRO 140), an anti-CCR5 humanized monoclonal antibody and is pursuing the clinical development of its PRO 140 drug candidate for the treatment of multi-drug resistant Human Immunodeficiency Virus ("HIV") infection, as well as related HIV infection indications. WHEREAS, the Parties desire that, upon regulatory approval of PRO 140 for the Initial Indication (as defined below), Vyera will Commercialize (as defined below) Licensed Products (as defined below) in the Field (as defined below) in the Territory (as defined below), all in accordance with the terms and conditions of this Agreement. NOW, THEREFORE, in consideration of the foregoing and the premises and conditions set forth herein, the Parties agree as follows: ARTICLE 1 DEFINITIONS 1.1 "AAA" has the meaning set forth in Section 12.3(a). 1.2 "AAI Agreement" has the meaning set forth in Section 9.2(o). 1.3 "Affiliate" means, with respect to a particular Party, a Person that controls, is controlled by or is under common control with such Party. For the purposes of this definition, the word "control" (including, with correlative meaning, the terms "controlled by" or "under the common control with") means the actual power, either directly or indirectly through one (1) or more intermediaries, to direct or cause the direction of the management and policies of such entity, whether by the ownership of fifty percent (50%) or more of the voting stock of such entity, by contract or otherwise. 1.4 "AGC Agreement" has the meaning set forth in Section 9.2(o). 1.5 "Agreement" has the meaning set forth in the introductory paragraph. 1.6 "Alliance Manager" means, with respect to each Party, the person appointed by such Party from within its organization to coordinate and facilitate the communication, interaction and cooperation of the Parties pursuant to this Agreement. The Alliance Managers shall be the primary contacts between the Parties with respect to the activities conducted pursuant to this Agreement. 1.7 "Annual WAC" means the annual wholesale acquisition cost for the Licensed Product. Source: CYTODYN INC., 10-Q, 1/9/2020 1.8 "API" means an active pharmaceutical ingredient, whether produced from a living organism or through synthetic process (i.e., any substance intended to be used in the manufacture of a drug product and that is intended to furnish pharmacological activity in the cure, treatment or prevention of disease). 1.9 "Applicable Law" means all applicable statutes, ordinances, regulations, rules, or orders of any kind whatsoever of any Governmental Authority, including, without limitation, the FDCA, Prescription Drug Marketing Act, the Generic Drug Enforcement Act of 1992 (21 U.S.C. §335a et seq.), U.S. Patent Act (35 U.S.C. §1 et seq.), Federal Civil False Claims Act (31 U.S.C. §3729 et seq.), and Anti-Kickback Statute (42 U.S.C. §1320a-7b et seq.), all as amended from time to time, together with any rules, regulations, and compliance guidance promulgated thereunder. 1.10 "Arbitration Request" has the meaning set forth in Section 12.3(b). 1.11 "Bankruptcy Laws" has the meaning set forth in Section 11.6(b). 1.12 "Biosimilar Competitor" means, with respect to the Licensed Product, a drug or biological product that has been determined by the FDA to be therapeutically equivalent to the Licensed Product, such that it may be substituted by a pharmacist for the Licensed Product in the Field in the Territory without the need for such pharmacist to seek authorization from the physician that prescribed the Licensed Product. 1.13 "Biosimilar Entry Date" means the first day of the first Calendar Quarter that occurs after Biosimilar Competitor(s) have achieved at least [***] in the Field in the Territory. 1.14 "BLA" means a Biologics License Application (as defined in the FDCA), including all supplements, amendments, variations, extensions and renewals thereof. 1.15 "Breaching Party" has the meaning set forth in Section 11.4. 1.16 "Business Day" means a day other than Saturday, Sunday or any other day on which commercial banks located in the State of New York or the State of Washington, U.S., are authorized
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Extract the exact clause related to "Effective Date" from the excerpt above.

assistant: December 17, 2019