Regeneron Sanofi Collaboration Agreement

As part of the research agreement, Sanofi-aventis will provide an $85 million advance to Regeneron and fund up to $475 million in research over the next five years. Sanofi-aventis will have the option to extend the research agreement for up to three years. The partners expect the proposed antibody agreement to be concluded in the first quarter of next year. Meanwhile, the current alliance for dupixent (dupilumab) is not subject to revision. Companies choose two clinical-stage bi antibodies for ongoing cooperation As part of the cooperation, Sanofi has acquired approximately 19% of Regeneron`s shares. The slides and management discussion will be available on the Regeneron website: www.regeneron.com on the Investor Relations presentation page at the time of the presentation. View original content:www.prnewswire.com/news-releases/regeneron-and-sanofi-restructure-immuno-oncology-collaboration-for-discovery-and-development-programs-300773538.html Regeneron Forward-Looking Statements and Use of Digital MediaCee forward-looking statements, risks and uncertainties regarding the future events and future performance of Regeneron Pharmaceuticals, Inc. (“Regeneron” or the “Company”) and actual events or results may differ materially from such forward-looking statements. Words such as “anticipate,” “expect,” “plan,” “believe,” “seek,” “appreciate,” variations in these words and similar expressions are intended to identify these forward-looking statements, although not all forward-looking statements contain these identifying words.

These statements relate to, and these risks and uncertainties include, among other things, the nature: the date and possible therapeutic applications of Regeneron products, candidates for products and research programs and clinical programs currently underway or scheduled, including, but not limited, in Libtayo® (cemiplimab-rwlc) and other Regeneron immuno-oncology programs (such as BCMAxCD3 and MUC16xCD3 specific programs, which are indicated in this press release); the likelihood, date and extent of possible marketing authorization and commercial introduction of Regeneron candidates at a late stage and new indications for marketed products, such as Libtayo, for the treatment of lung, cervical and skin cancers and other potential indications; the potential for discovery, development or cooperation agreements, including Regenerson`s agreements with Sanofi (or its related companies) (as discussed in this press release) to be terminated or terminated without further product success; unforeseen safety issues resulting from the administration of products and product candidates in patients, including complications or serious adverse events related to the use of Regeneron candidates in clinical trials; current regulatory obligations and monitoring of commercialized Regeneron products (such as Libtayo), research programs and clinical programs and business relationships, including those related to patient privacy; regulatory and administrative findings that may delay or limit Regeneron`s ability to develop or market Regeneron`s products and products; the availability and extent of reimbursement of company products by third-party payers, including private health and insurance insurers, health care organizations, pharmacy management companies and government-type programs such as Medicare and Medicaid; the coverage and reimbursement findings by these payers and the new policies and procedures adopted by these payers; Uncertainty about the market acceptance and economic success of Regeneron`s products and products, as well as the impact of studies (whether Regeneron or others and on behalf of or on volunteering) on the commercial success of these products and product candidates; Competing candidates for products and products that may be superior to Regeneron`s products and candidates; the extent to which the results of research and development programmes implemented by Regeneron or