Regeneron's Ovarian Cancer Drug Shows 73% Response Rate but High Toxicity, Shares Slide
REGN sits 35% above its 52-week low of $541.
Summary
Regeneron reported initial Phase 1/2 data for ubamatamab in low-grade serous ovarian cancer. In 11 heavily pretreated patients at 800 mg monotherapy, the objective response rate was 73%, all partial responses. However, safety concerns are significant: all 19 patients experienced treatment-emergent adverse events, 90% had cytokine release syndrome, and 74% had treatment-related adverse events including neutropenia and liver enzyme elevations. One patient discontinued due to a stroke deemed unrelated to the drug. The company plans a randomized Phase 3 trial and will share data with the FDA in coming months. The stock dropped after the data, reversing earlier gains from the expanded Sanofi collaboration announced this morning. The high response rate is encouraging, but the toxicity profile raises questions about the drug's commercial viability and regulatory path. Watch for FDA feedback and Phase 3 design details.
At the time of this announcement, REGN was trading at $728.38 on NASDAQ in the Life Sciences sector, with a market capitalization of approximately $75B. The 52-week trading range was $541.00 to $859.34. This news item was assessed with negative market sentiment and an importance score of 8 out of 10. Source: Seeking Alpha.