- Regeneron is years behind cancer immunotherapy rivals like Merck & Co. and Bristol-Myers Squibb. But, in their usual brash fashion, company executives on Tuesday made the case for their drug Libtayo and a broader immuno-oncology strategy that's advanced eight other candidates across a range of tumor types.
- Although Libtayo first won approval in a type of skin cancer not targeted by other companies, Regeneron said it expects to play in the largest, most competitive market, too: "PD-1 is a foundational technology in the immuno-oncology space," said Regeneron CEO Leonard Schleifer Tuesday. "Lung cancer is the biggest opportunity. We want to be there."
- On Tuesday, Regeneron also updated investors on the progress of two Phase 3 studies testing Libtayo in previously untreated lung cancer. Initial data from the first, an open-label study testing Libtayo in patients with high levels of a biomarker called PD-L1, showed tumor response rates roughly similar to what Merck's Keytruda posted in an early study.
Regeneron's Libtayo (cemiplimab) arrived on the U.S. market sixth in a drug class that includes the multi-billion dollar products Keytruda (pembrolizumab) and Opdivo (nivolumab).
The biotech's initial focus was on a cutaneous squamous cell carcinoma, a cancer type for which Libtayo was approved last September. In that specific indication, Libtayo was the first PD-1 or PD-L1 inhibitor available. But its smaller size meant Regeneron's immuno-oncology strategy would always involve taking on Merck and Bristol-Myers Squibb in more competitive areas like lung cancer.
How well Regeneron can do that will depend on success in studies like the two Phase 3 trials the biotech is running in first-line non-small cell lung cancer.
An update shared by Regeneron on Tuesday revealed both studies to be enrolling quickly, with potential results forthcoming next year for the first.
In that trial, 90% of the planned 700 participants have enrolled. Among the first 361 randomized patients with a minimum of 6 months of follow-up, 42% experienced decreases in tumor size following treatment with Libtayo, versus 22% for those given chemotherapy.
That's roughly analogous to the 45% overall response rate Keytruda posted in its initial Keynote-024 study, suggesting similar efficacy could be within Regeneron's reach.
After an interim analysis, the trial's data monitoring committee recommended the study continue as planned to the next planned look at survival data, expected in 2020.
The first part of the second study, meanwhile, has fully enrolled, and 20% of the 450 patients to be included in the second phase have joined as well. Regeneron expects enrollment to be completed in the second half of 2020.
More broadly, Regeneron is betting that efforts to combine immunotherapy with other approaches will eventually yield new successes, and potentially reset a field that's shifted several times.
"If it just turns out the only checkpoint inhibitor that continues to make a difference, as it has for the last five years in lung cancer, is a PD-1 inhibitor, we want to be there with ours and we want to compete," Schleifer said on a Tuesday conference call.
"But [we] could be one experiment away," he added, "and then everybody is back loaded up in the starting gate."
Regeneron's not the only one seeking to break Merck's hold on the immuno-oncology market. Positive trial results in lung cancer for both Bristol-Myers and AstraZeneca could lead to approvals, potentially making Regeneron a late entry yet again.