The US Food and Drug Administration (FDA) has rejected Regeneron Pharmaceutical’s approval application for odronextamab in two forms of lymphoma, amid concerns about the enrolment status of the ongoing confirmatory trials.

The FDA has been clamping down on requirements for accelerated approvals in oncology. An advisory committee met late last year to discuss ensuring clinical benefit via delayed confirmatory trials whilst maintaining timely access to promising treatments.

According to a 25 March press release, the FDA issued complete response letters (CRLs) highlighting the need for more data from the confirmatory trials. However, Regeneron specified that the CRLs did not identify any approvability issues about odronextamab’s efficacy, safety, trial design, labelling, or manufacturing.

The New York-based biotech was pursuing accelerated approval for odronextamab to treat patients with relapsed/refractory (r/r) follicular lymphoma and in r/rdiffuse large B-cell lymphoma who have not responded to two or more lines of systemic therapy. The drug was in Phase I and Phase II trials when the biologics licence application was submitted in September 2023.

Regeneron intended to use data from its Phase III OLYMPIA programme to support approval. While the company has initiated enrolment in the dose-finding portion of the trial, the FDA said that the confirmatory portion should be at the same stage. The agency added timelines should be laid out and agreed upon before any resubmission from the biotech. Regeneron said it will share updates on enrolment and regulatory timelines later this year and is working closely with the FDA.

Odronextamab is a CD20×CD3 bispecific antibody that facilitates local T-cell activation and cancer-cell killing by bridging CD20 on cancer cells with CD3-expressing T cells.

The antibody candidate has orphan drug status in Europe and is being evaluated for marketing authorisation by the European Medicines Agency. Odronextamab also has priority review status in the US. 

Regeneron only has one FDA-approved drug in its oncology portfolio – Libtayo (cemiplimab-rwlc). The PD-1 antibody, a monotherapy for two types of skin cancer, generated global sales of $869m in 2023. It is forecast to reach blockbuster status in 2024, estimated to make $1.1bn, according to GlobalData’s Pharma Intelligence Centre.

GlobalData is the parent company of Pharmaceutical Technology.