For Amgen's Nplate, No News is Good News

In case you didn’t have it circled on your calendar, July 23 was the user fee deadline for Amgen’s romiplostim (Nplate). And according to Amgen, FDA didn’t pick up the phone yesterday with a final answer on the platelet drug.

Without delving into specifics, Amgen says it was told by FDA that the agency will miss Nplate’s Prescription Drug User Fee Act deadline. The company says it is “optimistic that a final decision will be made soon,” but wouldn't speculate on exactly when the agency will be making an approval decision.

Maybe Amgen won’t speculate, but we will. We think the delay is actually good news for Nplate, and signals that—barring any last-minute surprises—an approval is just around the corner.

Simply put, if FDA weren’t pretty confident of the approvability of Nplate, it would have issued an “approvable” letter outlining its concerns with the BLA. Amgen would need to address FDA’s questions, submit a response and wait to hear back. (We should note that starting August 11, FDA will start sending "complete response" letters for all rejections.)

In this case, the review group is taking advantage of a new policy giving them the discretion to miss PDUFA deadlines. And it is fairly easy to see why the final review might take a bit longer than expected: Nplate will have a mandatory Risk Evaluation & Mitigation Strategy, or REMS, a new feature of the regulatory process created by legislation enacted last year. FDA is setting precedents with every REMS, and the agency has already extended or missed several deadlines for products covered by that authority.

There is a major caveat: when it comes to drug time lines, industry is treading in somewhat unknown territory these days. So while past history would suggest that a missed deadline would mean that approval is imminent, there is always a chance that the agency will let the application hang for a while.

That is certainly happening with FDA’s Cardio-Renal division, which has missed user fee dates for at least three NMEs this year: two anti-arrhythmics—Cardiome/Astellas’ vernakalant (Kynapid) and Solvay’s tedisamil (Pulzium)—and The Medicines Company’s clevidipine (Cleviprex) for acute hypertension.

But the oncology group has no history of letting applications linger. Quite the opposite: FDA doesn't always approve applications for cancer and related therapies, but it almost always acts quickly.

One thing is clear: as last week's slip-up by Business Wire illustrates, Amgen is ready to issue the approval press release whenever FDA is.