Important Note Regarding the September 11, 2017 Press Release Announcing Positive Dupilumab Topline Results from Phase 3 Trial in Uncontrolled Persistent Asthma

This press release has been corrected to address an error in the fourth sentence of the first paragraph. In the previous version, the mean improvement in lung function (FEV1) over placebo in mL was misstated in patients taking a 300 mg dose of dupilumab with 150 eosinophilic cells/microliter or greater. The correct mean improvement as assessed by FEV1 in these patients is 150 mL, not 210 mL as previously stated. Both versions correctly stated the corresponding percentage improvement (11 percent).

Contacts Regeneron: Media Relations Investor Relations Ilana Tabak Manisha Narasimhan, Ph.D.

Tel: + 1 (914) 847-3836 Tel: +1 (914) 847-5126

Mobile: +1 (914) 450-6677 Manisha.narasimhan@regeneron.com ilana.tabak@regeneron.com

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Regeneron Pharmaceuticals Inc. published this content on 21 September 2017 and is solely responsible for the information contained herein.
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