Biogen and UCB said Tuesday morning that data from a Phase 3 study for the lupus program dapirolizumab pegol were strong enough to convince it to launch a second pivotal trial to confirm the benefit and eventually take the drug to the FDA. But the companies are keeping much of the specifics under wraps for now.
The Phase 3 PHOENYCS GO study enrolled 321 patients to measure dapirolizumab pegol on top of standard of care in moderate-to-severe systemic lupus erythematosus (SLE). The trial achieved its primary endpoint, Biogen and UCB said, showing dapirolizumab pegol improved disease activity better than standard of care alone as measured by a composite assessment called BICLA after 48 weeks.
Dapirolizumab pegol also showed “clinical improvements” across secondary endpoints, including on other disease activity measurements and flares.
But Biogen and UCB did not disclose the magnitude of the benefits on any of the endpoints, the differences between the active and placebo arms, or whether they were statistically significant. A Biogen spokesperson said the company wouldn’t be sharing any additional information.
Diana GallagherNonetheless, the decision to launch another pivotal trial — which will happen before the end of 2024 — signifies executives are confident they can win over regulators. The companies did not initiate the two pivotal studies simultaneously when it first moved dapirolizumab pegol into Phase 3, Biogen head of lupus development Diana Gallagher told Endpoints News last week.
“We have a success criteria in our mind of what we would need to see, and then, working with our colleagues at UCB, hope to align and trigger that next study if we’re all on the same page,” Gallagher said.
Tuesday’s announcement follows a Phase 2 study from 2018, whose primary endpoint did not achieve statistical significance. After that trial concluded, however, Biogen chose to move forward and attempted to refine the best patients to enroll, immunology chief Adam Meyers said.
As part of the study’s inclusion criteria, Biogen and UCB sought out patients with persistent active disease and/or an active flare, which Meyers said was a “deliberate” choice.
“A p-value of 0.07 is not statistically significant, but depending on the context you look at, especially in a smaller Phase 2 study, it’s open for interpretation,” Meyers said. “I think that ultimately we made a choice, along with our collaborators at UCB, to progress [the drug].”
Dapirolizumab pegol is an “Fc-free polyethylene glycol (PEG)-conjugated antigen-binding (Fab’) fragment,” Biogen said. The drug inhibits CD40L signaling, which researchers theorize can help tamp down on the overactive immune cells that drive lupus.