UPDATED: AbbVie scores FDA approval for expanded Humira label

AbbVie ($ABBV) wants to get the most that it can out of blockbuster Humira before biosimilars in the U.S. and Europe come knocking. Part of that plan involves expanding the drug's label, and the Illinois pharma recently notched a win as the FDA approved Humira to treat a rare inflammatory skin disease.

Regulators OK'd the med for serious forms of hidradenitis suppurativa (HS), a condition that causes lesions on the armpits, groin, buttocks and under the breasts. Earlier this year, the agency awarded Humira orphan drug designation to treat the condition, potentially giving AbbVie 7 years of exclusivity for the med.

"We believe HS has the potential to be a meaningful indication ... with peak-year sales potential of $1 billion globally," Scott Brun, AbbVie's VP of pharmaceutical development, told FiercePharma in an email.

Regulators based their approval on two Phase III studies, which showed that the drug worked better than a placebo in treating painful skin conditions associated with the disease. And Humira is the only FDA-approved med for HS in adults, Brun said, providing a "much needed development in treatment options for patients" and giving AbbVie access to a larger patient pool.

The Illinois pharma needs all the help it can get as it counters some unpleasant realities for Humira, which brought in more than $12 billion in worldwide sales last year. The anti-inflammatory behemoth is set to go off patent in 2016 and already has biosimilar competition in India. And biosimilars will continue to take their toll on Humira sales, Citi analyst Andrew Baum predicted earlier this year, with revenues dropping from $16 billion in 2017 to $6 billion in 2022. "At year 3, biosimilars will achieve 36% U.S. market share in Humira patients and 25% in established Humira patients," Baum said in a note to investors.

But AbbVie is not taking the news lying down. "Humira is well-positioned to face the challenge of potential new entrants," Brun said, with 9 other approved indications in the U.S. The company recently snagged European approval for a new formulation of the drug to reduce the pain patients feel from injections. And AbbVie wants to keep the regulatory ball rolling, planning to submit applications in the U.S. and EU this year for Humira to treat inflammatory eye diseases, Brun added.

Meanwhile, the company is working hard to fill its blockbuster's big shoes, striking a deal earlier this year with cancer drugmaker Pharmacyclics ($PCYC) to get its hands on the company's promising blood cancer med Imbruvica. And analysts see AbbVie's new hep C med Viekira Pak as breaking the blockbuster barrier, which could potentially soften the blow.

- read AbbVie's statement

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Editor's note: This story was updated with comments from AbbVie.