Regeneron’s fianlimab/Libtayo combination shows positive results in advanced melanoma treatment

Regeneron has announced the presentation of positive data from multiple expansion cohorts of an initial phase 1 trial for an investigational combination of LAG-3 inhibitor fianlimab and PD-1 inhibitor Libtayo (cemiplimab) in advanced melanoma.

The results, which were shared in a mini-oral session at the European Society for Medical Oncology (ESMO) Congress 2022 in Paris, showed the combination treatment demonstrated greater than 60% response rates in two dose expansion cohorts.

"Combining LAG-3 and PD-1 inhibition has shown promise in advanced melanoma but achieving response rates above 50% has been challenging,” Israel Lowy, senior vice president, translational and clinical sciences, oncology at Regeneron said.

The data presented at ESMO was from three dose expansion cohorts in advanced melanoma, including two that enrolled patients who had not previously been treated with a PD-1 or PD-L1 inhibitor (PD-1/PD-L1-naïve) and one of patients who had received prior PD-1 or PD-L1 inhibitor therapy (PD-1/PD-L1-experienced).

The objective response rate (ORR) in the PD-1/PD-L1-experienced cohort was 13%. Meanwhile, updated results for one PD-1/PD-L1-naïve cohort demonstrated an ORR of 62.5%, and in a newly presented independent confirmatory cohort, an ORR of 65% was seen.

Adverse events of any grade in the two PD-1/PD-L1-naïve cohorts occurred in 96% of patients, with 29% considered serious.

“Notably, the safety profile for this combination appears in line with Libtayo monotherapy. A phase 3 trial in first-line metastatic melanoma is currently enrolling patients, and we look forward to opening additional trials with this combination in the near future," Lowy added.

The potential use of fianlimab and Libtayo for the treatment of advanced melanoma is investigational, and safety and efficacy of this combination have not been evaluated by any regulatory authority, the company underscored.