Amendment to the Amended and Restated Investor Agreement, dated as of May 25, 2020, by and among Regeneron Pharmaceuticals, Inc., Sanofi, Sanofi-Aventis US LLC, and Aventisub LLC

Exhibit 10.2

EXECUTION VERSION

Regeneron Pharmaceuticals, Inc.

777 Old Saw Mill River Road

Tarrytown, New York 10591

May 25, 2020

Sanofi

54, rue La Boétie

75008 Paris

France

Attention: Chief Financial Officer

Ladies and Gentlemen:

Reference is made to the Amended and Restated Investor Agreement (as may be amended from time to time, the “Investor Agreement”), dated as of January 11, 2014, by and among Sanofi, a company organized under the laws of France (“Sanofi”), sanofi-aventis US LLC, a Delaware limited liability company (“Sanofi US”), Aventisub LLC, a Delaware limited liability company (formerly Aventis Pharmaceuticals Inc., a Delaware corporation) (“Aventis”), sanofi-aventis Amérique du Nord, a société en nom collectif organized under the laws of France (the “Investor”, which was merged with Sanofi on October 30, 2018, and, together with Sanofi, Sanofi US and Aventis, the “Purchaser Parties”), and Regeneron Pharmaceuticals, Inc., a New York corporation (“Regeneron”), as amended pursuant to that certain letter agreement, dated as of January 7, 2018, by and among Regeneron and the affiliates of the Purchaser Parties party thereto (the “2018 Letter Agreement”). Capitalized terms that are used but not defined herein have the meanings given to such terms in the Investor Agreement.

The purpose of this Letter Agreement is to provide for certain matters in connection with (i) the underwritten offering by Sanofi and Aventis of shares (the “Offering Shares”) of common stock, par value $0.001 per share, of Regeneron (“Common Stock”) pursuant to Regeneron’s Registration Statement on Form S-3 (Registration No. 333-228352), with a base public offering size equal to all shares of Common Stock held by Sanofi and its Affiliates as of the date hereof (other than the Repurchase Shares (as defined below), any shares of Common Stock subject to the underwriter overallotment option to purchase additional Offering Shares and 400,000 shares of Common Stock that Sanofi intends to retain) (such offering, the “Offering”) and (ii) the repurchase (the “Repurchase” and, together with the Offering, the “Transaction”) by Regeneron of approximately $5 billion of Common Stock from Sanofi at the price at which the Offering Shares are sold to the public in the Offering, less the underwriting discount (the “Repurchase Shares”) pursuant to the Stock Repurchase Agreement, dated as of the date hereof, by and between Sanofi, Aventis and Regeneron.

Pursuant to Sections 9.2 and 9.5 of the Investor Agreement, the parties to this Letter Agreement agree as follows:

“7.1 [Reserved.]”

“(c) [Reserved.]”

Except as expressly set forth herein or in the waiver letter, dated as of the date hereof, by and among Regeneron and the Purchaser Parties, no provision of the Investor Agreement is modified or waived, and the Investor Agreement shall continue in full force and effect in accordance with its terms. All references in the Investor Agreement to the Investor Agreement shall be deemed to be references to the Investor Agreement after giving effect to this Letter Agreement.

Please confirm your agreement with the foregoing by returning a countersigned acknowledgement.

[Signature page follows.]

[Signature Page to Amendment to the Investor Agreement]