The end for AbbVie’s bestseller? US FDA approves Amgen’s Humira biosimilar

Humira (adalimumab) is the bestselling drug in the world, last year contributing over $14bn to AbbVie’s net revenues​ with $8.4bn of sales coming from the US.

But on Friday, AbbVie’s adalimumab dominance was struck a blow as the US Food and Drug Administration (FDA) approved Amjevita, a biosimilar version made by Amgen.

Amgen’s EVP of R&D Sean Harper described the news as “an exciting accomplishment,”​ marking “a new chapter in Amgen's story of being a leader in biotechnology.”​

Losing patents?​

AbbVie, in a statement sent to this publication, said it "​anticipated Amgen’s product would be approved."​ The firm has made no secret of its desire to retain market exclusivity until at least 2022 and is involved in a series of court battles with Amgen about the validity of a number of its patents.

In the latest of these, AbbVie filed a lawsuit against Amgen in August claiming involving ten of Humira’s patents.

“AbbVie identified 61 patents, but this lawsuit involves only 10 of them,”​ the firm said in its complaint. “That is Amgen’s choice, not AbbVie’s. The BPCIA gave Amgen the ability to cap the number of patents at issue in this lawsuit, rather than litigate all of AbbVie’s patents efficiently in a single wave and without delay.”​

In January​, AbbVie was successful in rebuffing a legal challenge from Amgen, with the US Patent Trial and Appel Board rejecting an inter partes review (IPR) against two of Humira’s formulation patents.

Fourth biosimilar​

Lawsuits aside, the earliest Amgen is able to launch would be March 22 – giving AbbVie the 180 days’ notice following FDA approval as affirmed in July​ by the US Court of Appeals for the Federal Circuit verdict in a landmark case brought about by Neulesta (pegfilgrastim) biosimilar developer Apotex against Amgen which, in this instance, was playing the part of the reference drugmaker.

Amjevita becomes the fourth biosimilar to be approved in the US, following Sandoz’ Zarxio (filgrastim), Pfizer’s Inflectra (infliximab) and Erelzi (etanercept),​ a second for Sandoz.

And in a statement, Janet Woodcock, director of the FDA’s Center for Drug Evaluation and Research (CDER), said: “The biosimilar pathway is still a new frontier and one that we expect will enhance access to treatment for patients with serious medical conditions.”​

As with the other three biosimilars, Amjevita has been approved as a biosimilar, not as an interchangeable product meaning that once launched it may not be substituted for the reference product by a pharmacist without the intervention of the health care provider who prescribed the originator biologic.

Industry still awaits guidance on interchangeability from the FDA.