- AbbVie, maker of the best-selling biologic drug Humira, sued Amgen in a federal court in Delaware last week, seeking to prevent Amgen from bringing its biosimilar version of Humira to market in the U.S., Bloomberg reports.
- Amgen recently secured the backing of an advisory panel to the Food and Drug Administration. Independent experts on the panel unanimously recommended approval for Amgen's biosimilar, setting up a potential final approval later this year.
- Humira accounted for 61% of AbbVie's total revenue last year and AbbVie hopes it can protect the drug's market for several more years. While the composition of matter patent for Humira expires in December in the U.S., other patents are valid through 2022.
AbbVie's lawsuit does not come as a surprise to anyone, given Humira's lucrative and still-growing (at least in the U.S.) revenue stream. AbbVie has maintained it can protect Humira from competition through 2022 and will likely be aggressive in trying to stop biosimilars from reaching the market.
According to Bloomberg, AbbVie contends in its lawsuit Amgen's Humira biosim would infringe on 10 patents and wants an injunction from the federal court to prevent Amgen from selling the drug, known as ABP-501.
A similar legal battle played out last year when the FDA approved Novartis' Zarxio, the first biosimilar approved in the U.S. That time it was Amgen who was on defense, trying to protect its drug Neupogen. Amgen was able to delay entry of the biosimilar for six months, giving it another half-year's worth of revenue.
As the biosimilar market in the U.S. is still nascent with only two approved biosimilars (Pfizer and Celltrion's Inflecta being the other), legal battles such as AbbVie's suit against Amgen take on greater importance for both the precedents to be set and the amount of as-yet untouched branded revenue at risk.
Take, for example, the case between Canadian drugmaker Apotex and Amgen. A federal appeals court last month affirmed that biosimilar drugmakers must provide brand-name companies of their intent to sell a biosimilar six months before marketing the drug.
While seemingly a minor technicality, the ruling has substantial relevance for this first wave of biosimilars. Biologic drugmakers already have 12 years of market exclusivity and an "extra" six months would give them more time to prepare legal challenges to a new entrant, not to mention adding another half-years' worth of protected sales.
Eventually, the FDA may begin to approve biosimilars for branded drugs still well within their 12 months of market exclusivity. If this occurs, a biosimilar drugmaker could provide six months' notice ahead of patent expiration and be ready to sell as soon as the 12 months are up—similar to how some generic drugs are approved under a federal law known as Hatch-Waxman.
Other threats for Humira loom as well. Samsung Bioepis, which just filed for European approval of a Humira biosimilar, plans to do the same in the U.S. and other companies are eyeing Abbvie's market share.