Regeneron slides after Phase 3 melanoma combo misses key endpoint

Regeneron Pharmaceuticals (REGN) is down 10.7% today. Here is some analysis on what might have caused this price movement.

Analysis: The selloff appears tied to a late-stage setback for Regeneron’s fianlimab + cemiplimab combination in first-line advanced melanoma, which failed to achieve statistical significance on its primary progression-free survival endpoint versus pembrolizumab. Even with a numeric PFS improvement, investors often punish high-profile oncology misses because they can reduce confidence in pipeline value and future growth drivers.

Details:

Regeneron disclosed that its Phase 3 trial of fianlimab (LAG-3) plus cemiplimab (Libtayo) in unresectable locally advanced or metastatic melanoma did not meet the primary endpoint of statistically significant improvement in progression-free survival versus pembrolizumab.

Reported figures indicated a numeric median PFS benefit of a little over five months for the high-dose combination versus pembrolizumab, but the result fell short of statistical significance (hazard ratio and p-value did not clear the required threshold).

The study enrolled roughly 1,500+ patients, making it a widely watched, pivotal readout for the LAG-3 program’s competitiveness against established PD-1 therapy.

Regeneron also announced a collaboration with Parabilis Medicines involving $125 million in upfront consideration and the potential for additional milestones, which likely did not outweigh the melanoma disappointment for near-term sentiment.

Sources:

GlobeNewswire, Fierce Biotech, Investing.com

Disclaimer: This price movement analysis was generated with the help of AI. Please double-check the information provided for mistakes.

$REGN Insider Trading Activity

$REGN insiders have traded $REGN stock on the open market 49 times in the past 6 months. Of those trades, 0 have been purchases and 49 have been sales.

Here’s a breakdown of recent trading of $REGN stock by insiders over the last 6 months:

BONNIE L BASSLER has made 0 purchases and 2 sales selling 2,260 shares for an estimated $1,770,000.
JASON PITOFSKY (SVP Controller) has made 0 purchases and 11 sales selling 2,036 shares for an estimated $1,585,058.
HUDA Y ZOGHBI has made 0 purchases and 11 sales selling 1,638 shares for an estimated $1,279,811.
ARTHUR F RYAN has made 0 purchases and 25 sales selling 200 shares for an estimated $148,376.

To track insider transactions, check out Quiver Quantitative's insider trading dashboard. You can access data on insider stock transactions through the Quiver Quantitative API insider transaction endpoint.

EARLY ACCESS

Receive REGN Data Alerts

Real-time alerts on filings, insider trades, and market signals — before everyone else.

Get Alerts →

$REGN Hedge Fund Activity

We have seen 703 institutional investors add shares of $REGN stock to their portfolio, and 636 decrease their positions in their most recent quarter.

Here are some of the largest recent moves:

WELLINGTON MANAGEMENT GROUP LLP added 1,172,994 shares (+176.5%) to their portfolio in Q1 2026, for an estimated $898,970,871
CAPITAL INTERNATIONAL INVESTORS removed 876,564 shares (-100.0%) from their portfolio in Q4 2025, for an estimated $676,593,454
FMR LLC removed 801,374 shares (-34.5%) from their portfolio in Q1 2026, for an estimated $614,165,019
D. E. SHAW & CO., INC. removed 706,118 shares (-82.0%) from their portfolio in Q4 2025, for an estimated $545,031,300
TWO SIGMA INVESTMENTS, LP added 531,085 shares (+188.9%) to their portfolio in Q1 2026, for an estimated $407,018,233
MARSHALL WACE, LLP removed 478,198 shares (-99.9%) from their portfolio in Q1 2026, for an estimated $366,486,165
HOLOCENE ADVISORS, LP removed 460,723 shares (-100.0%) from their portfolio in Q1 2026, for an estimated $353,093,499

To track hedge funds' stock portfolios, check out Quiver Quantitative's institutional holdings dashboard. You can access data on hedge funds moves and 13F filings through the Quiver Quantitative API 13F endpoint.

$REGN Congressional Stock Trading

Members of Congress have traded $REGN stock 2 times in the past 6 months. Of those trades, 2 have been purchases and 0 have been sales.

Here’s a breakdown of recent trading of $REGN stock by members of Congress over the last 6 months:

REPRESENTATIVE JULIA LETLOW purchased up to $15,000 on 02/12.
REPRESENTATIVE GILBERT RAY CISNEROS, JR. purchased up to $15,000 on 11/18.

To track congressional stock trading, check out Quiver Quantitative's congressional trading dashboard. You can access data on congressional stock trades through the Quiver Quantitative API Congress trades endpoint.

$REGN Analyst Ratings

Wall Street analysts have issued reports on $REGN in the last several months. We have seen 6 firms issue buy ratings on the stock, and 0 firms issue sell ratings.

Here are some recent analyst ratings:

Barclays issued a "Overweight" rating on 04/30/2026
Truist Securities issued a "Buy" rating on 04/30/2026
Cantor Fitzgerald issued a "Overweight" rating on 02/02/2026
B of A Securities issued a "Buy" rating on 01/07/2026
BMO Capital issued a "Outperform" rating on 12/04/2025
HSBC issued a "Buy" rating on 11/24/2025

To track analyst ratings and price targets for $REGN, check out Quiver Quantitative's $REGN forecast page.

$REGN Price Targets

Multiple analysts have issued price targets for $REGN recently. We have seen 20 analysts offer price targets for $REGN in the last 6 months, with a median target of $857.5.

Here are some recent targets:

Biren Amin from Piper Sandler set a target price of $855.0 on 05/18/2026
Brian Abrahams from RBC Capital set a target price of $707.0 on 05/18/2026
Geoff Meacham from Citigroup set a target price of $700.0 on 05/18/2026
Andrew Berens from Leerink Partners set a target price of $641.0 on 05/18/2026
Mohit Bansal from Wells Fargo set a target price of $700.0 on 05/18/2026
Yatin Suneja from Guggenheim set a target price of $995.0 on 05/01/2026
Gregory Renza from Truist Securities set a target price of $796.0 on 04/30/2026

This article is not financial advice. See Quiver Quantitative's disclaimers for more information. Note that there may be inaccuracies due to mistakes in ticker-mapping, and other anomalies.