Sarilumab's new Humira-beating data poses another threat to AbbVie's megablockbuster sales

AbbVie ($ABBV) is watching competitors to top-seller Humira come up the pipeline at several of its Big Pharma peers. And now, one of those competitors topped the rheumatoid arthritis behemoth in a late-stage trial.

On Friday, Sanofi ($SNY) and Regeneron ($REGN) said their candidate RA drug, sarilumab, bested Humira at improving signs and symptoms of the autoimmune disease after 24 weeks of treatment. The trial hit its secondary endpoints, too, including other measures of improvement in RA symptoms and physical function.

It's an important win for the partners, who are looking to break into a crowded treatment landscape headlined by megablockbusters such as Humira and Amgen's ($AMGN) Enbrel. "Despite the availability of a wide range of treatment options, we believe that new therapies are needed to further address unmet needs of RA patients," Simon Cooper, a VP at Sanofi's immunology and inflammation department, said in a statement.

For AbbVie, it's yet another forthcoming sales threat to its chart-topping drug. The Illinois pharma already has plenty of biosimilars makers taking aim at its standout product, and some industry-watchers predict they'll do some real damage down the line. Last summer, results from a survey of biosimilar industry members, payers, regulators, lawyers and healthcare investors pegged Humira as the drug whose copies would rack up the biggest biosimilars sales, and Citi analyst Andrew Baum has predicted knockoffs would cut Humira's U.S. revenues to $6 billion by 2022.

Biosimilar rivals to Humira's head-to-head competitors could snap up share, too--and on the company's Q2 conference call last year, CEO Richard Gonzalez worked to assure investors that biosimilars of Johnson & Johnson ($JNJ) heavyweight Remicade weren't stealing sales.

AbbVie isn't standing idly by, though. In psoriasis--another of Humira's major indications--it recently inked a $595 million deal with Boehringer Ingelheim for rights to the German pharma's Phase III candidate, BI655066.

- read the release

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