Regeneron Shares Plunge 10% After Melanoma Trial Misses PFS Endpoint
Regeneron’s high-dose fianlimab plus pembrolizumab regimen failed to reach statistical significance for median progression-free survival (11.5 vs 6.4 months; p=0.0627) in its Phase 3 melanoma trial, triggering a 10% premarket share decline. Citi and BMO cut ratings and price targets, while Regeneron adds a radiopharmaceutical development deal with Telix Pharmaceuticals.
1. Phase 3 Trial Results
The high-dose fianlimab plus pembrolizumab combination in metastatic melanoma achieved a median progression-free survival of 11.5 months versus 6.4 months for pembrolizumab alone but failed to reach statistical significance (p=0.0627) for its primary endpoint.
2. Market Reaction and Analyst Response
Shares fell about 10% in premarket trading, prompting Citi to downgrade to Neutral with a $700 target and BMO to cut its target by nearly 20%, citing disappointment in what was to be the defining catalyst of the first half of 2026.
3. Telix Partnership Details
Regeneron entered a collaboration with Telix Pharmaceuticals to develop and commercialize next-generation radiopharmaceutical therapies, expanding its oncology pipeline beyond immuno-oncology assets.