Regeneron, Sanofi pull FDA application for Libtayo in cervical cancer

The move is curious considering Libtayo has demonstrated an overall survival benefit in the indication.

Regeneron Pharmaceuticals and its partner Sanofi voluntarily withdrew their application with the United States (US) food drug regulator to broaden the use of their anti-cancer drug Libtayo in advanced cervical cancer patients. The application for the monoclonal antibody as a second-line treatment in patients was withdrawn "after the firms and the US Food and Drug Administration were unable to coordinate on certain post-marketing studies," according to the companies. The move is puzzling considering Libtayo has demonstrated an overall survival benefit in the indication. According to Regeneron and Sanofi, marketing applications are still being discussed with regulatory authorities outside of the (US). The drug has already been approved for some types of skin and lung cancer.

That announcement came just days after Merck's Keytruda, which had previously received an accelerated second-line approval in cervical cancer, received a first-line approval, converting the second-line approval to a complete nod. It also followed Agenus’ decision to pull its application for fast approval of balstilimab in October of last year. Balstilimab’s therapeutic area was also in second-line cervical cancer. One distinction between the applications was that Agenus used biomarker data to support its treatment, whereas Regeneron and Sanofi used survival figures.In a phase 3 trial in March of last year, the firms found that Libtayo reduced the risk of death by 31% compared to chemotherapy in patients with recurrent or metastatic cervical cancer that had progressed on platinum-based chemotherapy.