SPARK THERAPEUTICS, INC. 3,500,000 Shares of Common Stock, par value $0.001 per share Underwriting AgreementSpark Therapeutics, Inc. • June 15th, 2016 • Biological products, (no disgnostic substances) • New York
Spark Therapeutics, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representative (the “Representative”), an aggregate of 2,500,000 shares of Common Stock, par value $0.001 per share, of the Company, and certain stockholders of the Company named in Schedule 2 hereto (the “Selling Stockholders”) propose to sell to the several Underwriters an aggregate of 1,000,000 shares of Common Stock of the Company (collectively, the “Underwritten Shares”). To the extent there is only one Selling Stockholder listed on Schedule 2 hereto, the term Selling Stockholders as used herein shall mean such Selling Stockholder listed on Schedule 2 hereto, and the term Selling Stockholders shall mean either the singular or plural as the context requires. In addition, the Company proposes to issue and sell, at the option of the Underwriters, up to an additional 525,000 shares of Commo
