The FDA’s approval of Libtayo was based on Phase 3 trial data showing a 68% reduction in the risk of recurrence or death in high-risk CSCC patients.
Retail chatter picked up around Regeneron Pharmaceuticals late Wednesday after the U.S. Food and Drug Administration (FDA) granted the company’s Libtayo approval as a treatment for patients with cutaneous squamous cell carcinoma (CSCC) with high risk of recurrence after surgery and radiation.
Shares of the company ended down 3.3% at $563.86 Wednesday, marking its third consecutive session of declines, and moved 0.3% higher after hours.
The FDA expanded the approval of Libtayo for use in CSCC patients based on data from the Phase 3 C-POST trial in which Libtayo showed a 68% reduction in the risk of disease recurrence or death compared with placebo.
Regeneron said the approval has the potential to change the treatment paradigm for patients with earlier-stage disease, expanding beyond its previous use in advanced CSCC. Libtayo, a PD-1 inhibitor, is now approved for five cancer indications, including certain forms of lung, basal cell, and cervical cancers.
Until now, we lacked options to help prevent recurrence for patients whose CSCC was removed by surgery and radiation, said Vishal Patel of George Washington University, calling the data “practice-changing.” Regeneron’s Chief Scientific Officer, George Yancopoulos, added that the approval strengthens Libtayo’s position as a “versatile PD-1 inhibitor” backed by compelling survival data.
The drug’s safety profile remained consistent with what’s been seen in past studies, with most side effects described as mild, including itching, and thyroid issues.
To help patients access treatment, Regeneron also launched Libtayo Surround, a support program offering financial and educational resources.
On Stocktwits, retail sentiment was ‘extremely bullish’ amid a 211% surge in 24-hour message volume.
One user noted that Regeneron’s recent price action and news made it look like a good “buying opportunity,” saying they entered the stock around $564 after it touched a key trend line.
Another user mentioned that shares were trading near their average cost and that it seemed like a reasonable time to add more.
Regeneron’s stock has declined 20.5% so far in 2025.
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