Genmab A/S (GMAB) notched a significant regulatory win on Tuesday when the FDA granted traditional approval to Epkinly (epcoritamab-bysp) for treating a specific type of blood cancer. The approval covers two uses: in combination with lenalidomide and rituximab for relapsed or refractory follicular lymphoma, and as a standalone treatment for the same condition after patients have tried at least two other systemic therapies.
This traditional approval builds on the accelerated approval Epkinly received in 2024 for the same indication. The difference? Traditional approval means the FDA reviewed comprehensive data proving the drug actually improves patient outcomes, not just early signals that it might work.
The combination therapy approval stems from the EPCORE FL-1 study, an open-label randomized trial involving 488 patients with relapsed or refractory follicular lymphoma. Researchers split patients evenly between two groups: one receiving Epkinly plus lenalidomide and rituximab (known together as R2), and a control group getting just R2.
The patient population had typically been through one prior systemic therapy, though 24% had received two previous treatments and 17% had three or more. So these weren't newly diagnosed patients—they were people whose disease had already proven stubborn.
The results were striking. The FDA based its approval decision on two key metrics: progression-free survival and overall response rate. The Epkinly combination demonstrated clear superiority on both fronts, with a progression-free survival hazard ratio of 0.21—meaning patients on Epkinly had roughly one-fifth the risk of their disease progressing compared to the control group.
In practical terms, the median progression-free survival in the control arm was 11.2 months. In the Epkinly arm? Researchers couldn't even calculate a median because not enough patients had experienced disease progression—that's what "not reached" means in clinical trial speak, and it's generally good news.
The overall response rate told a similar story: 89% of patients in the Epkinly arm responded to treatment versus 74% in the control group.
Separately, Genmab shared updated data in October from a Phase 1/2 trial evaluating another investigational drug, rinatabart sesutecan (Rina-S), for advanced endometrial cancer. That trial showed a 50% confirmed objective response rate in heavily pretreated patients at the 100 mg/m² dose given every three weeks, including two complete responses.
After a year of follow-up, 63.6% of responders in that dose cohort maintained their responses and continued treatment. Notably, responses occurred regardless of FRα expression levels, suggesting the treatment might work across a broader patient population.
GMAB Price Action: Genmab stock was down 1.55% at $29.95 at publication on Tuesday.