- Insurers would be justified in imposing some initial limits on coverage of a new class of preventive migraine drugs, a new report from the Institute for Clinical and Economic Review said, citing insufficient evidence around the treatments' long-term safety and relative expense to current generic medicines.
- A panel of experts convened by ICER, a drug cost watchdog, concluded that prior authorization criteria would be "reasonable" to balance use of the drugs, known as CGRP inhibitors, against their added cost and remaining clinical uncertainties.
- One CGRP inhibitor, Aimovig from Amgen and Novartis, is already approved in the U.S., while two others from Eli Lilly and Teva Pharmaceuticals are currently under review by the Food and Drug Administration. Expectations are high for the class, which represents the first new preventive option for migraine sufferers since the introduction of Botox for the condition nearly a decade ago.
In May, Amgen and Novartis surprised some by pricing Aimovig (erenumab) at a wholesale acquisition cost of $6,900 per year, below Wall Street's expectations. The companies were the first to win U.S. approval of a CGRP inhibitor, securing an important first-mover advantage ahead of looming competition from Eli Lilly, Teva and several other biotech rivals.
Aimovig's pricing appeared designed to secure broad payer coverage, and a leading share of a market some predict to be worth several billion dollars a year.
Notably, the price fell within cost-effectiveness thresholds set out by ICER in an earlier draft report on the CGRP inhibitor class. In recent years, ICER's value assessments have become a flash point in skirmishes between drugmkers and payers over the prices of new medicines.
In its now finalized report, ICER calculated the annual net price of Aimovig would need to fall within a range from $3,700 to $5,300 to be considered cost effective. Assuming a 27% discount from WAC — about industry average for branded drugs — Aimovig would cost about $5,000 per year and just clear ICER's upper threshold.
That's still much more expensive than an old, now generic, class of migraine drugs called triptans. And, given the long-term safety of CGRP inhibitors remains unclear, a panel of experts convened by ICER judged prior authorization restrictions would be suitable for insurers to adopt.
The panel contained representatives from Amgen and Teva, as well as from major pharmacy benefit manager Express Scripts and from CalPERS, California's large public pension system.
While ICER found clinical evidence supported a health benefit to CGRP inhibitors in people with no other treatment options, the group judged existing data insufficient to compare the drugs directly with oral agents like triptans or with Botox. Importantly, this only applied to chronic migraine patients, who experience more than 15 "headache days" per month and represent about 10% of the migraine patient population in the U.S.
Given the evidence suggestive of benefit, ICER noted that authorization criteria should be "relatively streamlined," and require only a physician statement that a patient has previously tried and failed on other preventive therapies. ICER did not suggest requiring submission of extensive clinical documentation to prove prior failures.
This recommendation generally fits with analysts and industry expectations of how insurers would approach coverage of the drugs. Eli Lilly, for example, has been expecting insurers would require patients to fail first on triptans before being prescribed an anti-CGRP drug.
That ICER is also on board with this approach could be another signal the drugs may secure generally favorable coverage.
In a May note to investors, Leerink analyst Geoffrey Porges noted that experts polled by the investment firm indicated a sizable number of patients will have already tried several drugs and be able to move quickly on to CGRP inhibitors.
Prescription numbers from Iqvia cited by Mizuho indicate about 2,300 patients have been prescribed Aimovig since its launch, although many of those prescriptions are considered "free drug," or samples.
In its report, ICER also warned drugmakers seeking approval of competing CGRP inhibitors to "exercise restraint" in pricing their therapies.
Eli Lilly expects a decision from the FDA on approval of its drug galcanezumab by September. FDA review of Teva's fremanezumab has been delayed by manufacturing issues, but the Israeli drugmaker still expects to secure an OK before the end of 2018.