- An immunotherapy developed by Regeneron and Sanofi helped people with advanced, but previously untreated, lung cancer live longer than did chemotherapy, according to study results announced by the companies Monday.
- Only lung cancer patients with high levels of a biomarker known as PD-L1 were included in the Phase 3 study, which is critical to the companies' plans to play a larger role in the market for immune-boosting cancer drugs.
- The companies plan to submit their findings to regulators in the U.S. and Europe for approval of their treatment, called cemiplimab and sold as Libtayo for a type of skin cancer. If cleared, Libtayo would join Merck & Co.'s Keytruda and Roche's Tecentriq as immunotherapy options in first-line non-small cell lung cancer, or NSCLC.
Regeneron and Sanofi are retracing a strategy taken by Merck four years ago with Keytruda, which became the dominant cancer immunotherapy on the back of its success in lung cancer.
Like Merck did, the two partners are trying first in a subset of patients whose cancers express the protein PD-L1 in greater than 50% of tumor cells. These patients are generally more responsive to immunotherapy — which, while powerful, doesn't work universally well.
Results disclosed by Regeneron and Sanofi show treatment with Libtayo reduced the risk of death by a third versus platinum-based chemotherapy, until only recently the standard of care for first-line lung cancer. That compares well with the 31% risk reduction observed in Merck's Keynote-042 study of Keytruda in a similar lung cancer patient population.
No other data from the 710 patients tested in the study were released, although the companies said investigators didn't observe any new side effects. Previous trials found Libtayo associated with fatigue, rash, diarrhea and, more rarely, immune-mediated reactions.
Although Libtayo is the sixth drug of its class to be approved in the U.S. Regeneron and Sanofi are attempting to make the case that it shares more similarities with Keytruda than with later-approved drugs from Roche, AstraZeneca and Pfizer.
Only Keytruda is cleared as a monotherapy for first-line lung cancer, while its approval in combination with chemotherapy has fueled widespread use and billions in sales. Roche's Tecentriq is also a competitor, following lung cancer OKs as part of drug regimens involving Avastin and other chemotherapies.
Bristol Myers Squibb's difficulties in proving its immunotherapy Opdivo in previously untreated lung cancer, meanwhile, have erased a once-formidable marketing edge and put pressure on the New York pharma.
Both Bristol Myers and Roche hope to win new lung cancer approvals this year.
Securing positive results from this first Phase 3 lung cancer study are a good first step for Regeneron and Sanofi, but may not do much to boost Libtayo commercially, if it is eventually approved for the tumor type.
"Although approaching efficacy seen with Merck's Keytruda, Libtayo will likely struggle to gain share as it enters a market with entrenched competitors and no clear differentiation," wrote Steve Scala, an analyst at Cowen, in a Monday note to clients.
Regeneron and Sanofi are also running another late-stage trial pairing Libtayo with chemotherapy in lung cancer patients, irrespective of PD-L1 status. Enrollment is expected to complete later this year, the companies said.