Regeneron hit by advanced melanoma treatment failing trial

Regeneron shares tumbled 10% in early Wall Street trading on Monday, following the failure of its experimental advanced melanoma treatment in a Phase III clinical trial. The US pharmaceutical company announced that the combination of fianlimab and cemiplimab failed to meet the study's primary endpoint of improving progression-free survival, the duration during which the disease does not worsen.

This setback adds to several recent challenges for the group, including regulatory delays regarding the pre-filled version of its ophthalmology treatment Eylea and the late-stage failure of itepekimab for chronic obstructive pulmonary disease (COPD).

In the trial involving 1,546 patients, the tested combination showed a numerical improvement of 5.1 months in median progression-free survival compared to Merck's Keytruda, although it failed to reach the required threshold for statistical significance.

Several analysts believe that this string of failures increases pressure on the group's upcoming clinical developments over the next 12 to 18 months. Regeneron is nevertheless proceeding with another trial comparing this combination to Bristol Myers Squibb's Opdualag, although some brokerages are now more cautious regarding the chances of success.

The group also announced a partnership with Parabilis Medicines, which could receive up to $2.2bn in milestone payments for the development of new treatments targeting hard-to-treat diseases.