Piper Jaffray Defends Alder Despite Stock Slump, Looks To What's Next In Migraine Management

Eptinezumab was successful in meeting the primary and key secondary endpoints in a phase 3 trial, and the company plans on filing for approval of the drug with the U.S. Food and Drug Administration in the bottom half of 2017.

Alder's results "have been interpreted in a tough competitive context," Piper Jaffray's Charles C. Duncan, Ph.D., commented in a research report. Investors should be focusing on the "good-sized" (40 percent-plus) subgroup of "super-type responders to therapy after just two doses, and some of whom convert as early as the first several days on therapy."

"While the placebo-adjusted reduction in monthly migraine days over weeks 1-12 looked 'just ok' we also note that, potentially consistent with an IV therapy, the placebo response was higher than for other Phase III programs we've seen," the analyst continued.

Clinical Benefit

Among the 75 percent responder analysis for the 300mg does, it appears that around one-third of patients respond in the first 12 weeks post-infusion. The figure increased to 40–45 percent after a second dose, the analyst added. On early response to therapy, certain patients experience an interruption of migraine following the first dose, and on average maintained the benefit during the first month of therapy.

"In the absence of a biomarker for response to epti' (or any of the antibodies in the class) we believe this early response is key to driving preference and also potentially reimbursement," Duncan also wrote.

The drug's safety also appears to be consistent with a placebo at all dose levels and following a second infusion. This wasn't a major risk heading into the results, but nevertheless, it was "reassuring to see no surprises."

What's Next?

Alder is expected to share more details from the dataset at future medical events, including at IHS in September. The analyst will be looking out for changes in headache severity, patient function and healthcare utilization. The additional data will "further support what we see as a clinically meaningful benefit to patients in the trial."

The company is also looking for its dosing regimen (or regimens) to be included in the back half of 2018 BLA and exploring the potential feasibility of a self-administered program, the analyst emphasized. The 300mg dose looks "most viable," but the 100mg dose could also be on the label for certain patient populations.

"It's also worth noting that we're not overly concerned about timelines of a self-administered program, as we see the IV differentiating epti' for the positive vs others in the space," Duncan concluded.

Shares of Alder BioPharmaceuticals remain Overweight rated with an unchanged $47 price target.