Bad news for AbbVie: Humira copies expected to rack up biggest biosim sales

Here's something AbbVie ($ABBV) doesn't want to hear: Industry watchers expect biosimilars for its top moneymaker Humira to be the most successful copycat biologics launched in the U.S. and Europe.

That's according to biosimilar industry members, payers, regulators, lawyers and healthcare investors who participated in a survey conducted by Bloomberg Intelligence. They see Humira's $12.5 billion in 2014 revenue--and the $14 billion it's expected to generate this year--as a prime opportunity for knockoff makers.

That's bad news for the Illinois pharma, which currently relies on the blockbuster for quite a bit of its top-line haul--despite recent attempts at diversification, a la its $21 billion deal for Imbruvica-maker Pharmacyclics. And Humira already has a biosimilar on the market in India thanks to local company Zydus Cadila.

Of course, "the true opportunity for a biosimilar version of Humira will ultimately depend upon whether the label is fully extrapolated and it is granted all indications of the originator, particularly in the U.S.," Bloomberg Intelligence analysts noted. AbbVie's juggernaut, originally approved to treat rheumatoid arthritis, also boasts indications in plaque psoriasis, Crohn's disease, ulcerative colitis, psoriatic arthritis, and ankylosing spondylitis.

And there could be all kinds of additional hurdles to biosimilars gaining traction in the U.S. market. Among them are concerns over interchangeability; only 20% to 40% of biosimilar drugs seeking interchangeability approval will succeed, survey respondents predicted. And even if they do, industry-watchers are guessing the drugs could face initial skepticism from doctors and patients.

All of those question marks have led some to believe it'll be a little while before AbbVie has much to worry about--but others, like Citi analyst Andrew Baum, disagree. In February, he predicted biosimilar rivals would cut into U.S. revenues sooner rather than later, knocking sales to $6 billion by 2022.

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