Although the FDA approved its fourth biosimilar Friday – Amgen Inc.'s Amjevita, which references Abbvie Inc.'s blockbuster Humira – the U.S. is not much closer to having a truly competitive biosimilars market, as only one biosimilar has actually launched.
With every new biosimilar it approves, the FDA brings more certainty to the pathway, but the agency's Janet Woodcock described the regulatory path as "still a new frontier" when the Amjevita (adalimumab-atto) approval was announced. If the pathway is a frontier, then the marketplace is more like an unexplored wilderness. With Sandoz Inc.'s Zarxio (filgrastim-sndz) the lone biosimilar out there, it's too soon to speculate about market uptake and actual savings.
Zarxio may soon have some company. The 180-day notice of commercial marketing, which must be given to the innovator once a biosimilar is licensed in the U.S., will end next week for Celltrion Inc.'s biosimilar that will be marketed in the U.S. by Pfizer Inc. as Inflectra (infliximab-dyyb), referencing Remicade (Janssen Biotech Inc.).
While Pfizer hasn't announced a launch date yet, it said Monday that it's "continuing with the preparation of our launch plans for Inflectra for 2016."
As for Amjevita, it could have more than a six-month wait before it ventures onto the market, given Humira's thicket of patents and ongoing patent litigation between the two companies. In the meantime, there are a lot of guessing games about when Amgen will launch its biosimilar, as the Thousand Oaks, Calif., company is keeping mum about launch and pricing plans for its first follow-on.
Abbvie hasn't been as quiet. It indicated earlier this year that, given Humira's patent portfolio, it doesn't expect to see biosimilar competition until late 2018 at the earliest. And even then, it predicted Humira might hold its own through 2022. If so, Humira, which was first approved in 2002, would enjoy a 20-year run with little competition. Once biosimilars get a grip on the market, Abbvie anticipates that 30 percent of Humira's "opportunity" will go to biosimilars over time. (See BioWorld Today, April 29, 2016.)
Abbvie, of North Chicago, needs to hold off the competition as long as possible. In the first half of the year, Humira generated more than $7.7 billion in global net revenue, accounting for 62 percent of the company's total revenue for the period. Nearly 64 percent of the Humira revenue, $4.9 billion, came from the U.S.
One of the ways Abbvie is protecting its turf is through ongoing development of Humira for new indications. In June, the FDA approved expanding Humira's label to include uveitis; the biologic also was approved for new indications in the EU this year. (The EMA is currently reviewing Amgen's biosimilar.)
Although the FDA approved an extrapolated label for Amjevita, it's a "skinny" label that includes only seven of the 10 indications approved for Humira in the U.S., since the other three still have market exclusivity. The innovator biologic has 14 indications in other markets.
When Amjevita does launch, it could be a test of what it will take to shape a robust biosimilar market. Besides directly competing with Humira, it will indirectly compete with Remicade, Inflectra, Amgen's own Enbrel (etanercept) and the third biosimilar the FDA approved, Sandoz's Erelzi, which references Enbrel, as they're all tumor necrosis factor inhibitors used in immunology. Amjevita also could face direct competition from several other Humira biosimilars that are now in late-stage development.
EMA, FDA CLUSTER ON RARE DISEASES
The EMA and FDA created a "cluster" to confidentially exchange their regulatory experiences and best practices to advance the development of new treatments for rare diseases.
The exchange will include draft documents, policies under development and detailed information supporting the scientific basis for approving drugs for rare diseases. The shared data also will involve such issues as:
• trial design in small populations;
• use of statistical analysis methods;
• selection and validation of trial endpoints;
• preclinical evidence to support development programs;
• design of postmarketing studies, especially in cases of conditional authorization or accelerated approval;
• risk management strategies.