Regeneron and Sanofi Announce Positive DISCOVER Trial Results for Dupixent in Adults and Adolescents with Moderate-to-Severe Atopic Dermatitis in Communities of Color

Regeneron and Sanofi announced positive Phase 4 trial results for Dupixent in treating moderate-to-severe atopic dermatitis in adults and adolescents with skin of color, showing a 76% improvement in overall disease severity. The DISCOVER trial, with a predominantly Black participant group, demonstrated significant reductions in symptoms like itchiness, dry skin, and hyperpigmentation. While the safety profile was consistent with previous findings, the overall adverse event rate was 42%, including allergic reactions and eye problems, warranting further monitoring.

Analysis

Regeneron Pharmaceuticals (REGN) and Sanofi (SNY) announced positive results from the DISCOVER Phase 4 trial for Dupixent, demonstrating its efficacy in treating moderate-to-severe atopic dermatitis in adults and adolescents with skin of color. Notably, over 76% of participants achieved a 75% or greater improvement in overall disease severity (EASI-75), and patients experienced significant reductions in symptoms such as hyperpigmentation, dry skin, and itch. These findings are crucial as they address unique clinical challenges in an underserved patient demographic and were highlighted at the 2025 Revolutionizing Atopic Dermatitis Conference, potentially boosting Dupixent's market perception. However, an overall adverse event rate of 42% was reported in the trial, with serious side effects including allergic reactions and eye problems, which necessitates careful monitoring despite the safety profile being generally consistent with previous indications. From a market perspective, Wall Street analysts maintain a positive outlook on REGN, with four firms issuing buy or overweight ratings in recent months and a median price target of $802.5. Conversely, institutional investor sentiment appears mixed; in Q1 2025, 771 institutions decreased their REGN positions while 648 added shares, with significant reductions from JPMORGAN CHASE & CO (-19.8%) and CAPITAL WORLD INVESTORS (-30.2%), contrasting with notable additions by GOLDMAN SACHS GROUP INC (+77.3%) and TWO SIGMA ADVISERS (+553,800 shares). Additionally, Congressional stock trading activity in REGN over the past six months shows a clear trend of selling, with 8 sales versus 1 purchase.

Key Decisions for Investors

• Consider the positive Dupixent Phase 4 trial data as a key factor for expanding its addressable market to diverse populations, potentially driving future revenue growth for Regeneron, while remaining vigilant about the reported 42% adverse event rate and specific serious side effects which could influence physician prescribing patterns and patient uptake.
• Evaluate REGN's investment profile by weighing the strong analyst consensus (four recent buy/overweight ratings, median price target $802.5) against the backdrop of net institutional selling in Q1 2025, including substantial divestitures by major funds, and the observed pattern of net sales by members of Congress.
• Monitor ongoing clinical adoption, post-marketing safety surveillance data for Dupixent, and its competitive positioning, particularly concerning its tolerability in diverse patient groups, as these elements will be critical in assessing the realization of its full commercial potential following these trial results.