Look out, CLL. AbbVie and Roche's new venetoclax is on FDA's priority track

AbbVie ($ABBV) and Roche ($RHHBY) scored priority review for their new leukemia therapy venetoclax, putting the companies in line for a launch within 6 months. With analysts predicting 2020 sales of $2 billion--and both companies expecting biosimilar competition by 2018--the med could be a welcome addition to their lineups.

The priority review tag was based on a Phase II study that posted an overall response rate of 79.4% and a complete response in 7.5%. The approval would be for venetoclax as a solo treatment for relapsed chronic lymphocytic leukemia (CLL) in patients with a 17p gene deletion, a marker of aggressive disease.

But venetoclax, formerly known as ABT-199, is important to AbbVie for another reason: It's seen as a new growth engine for Imbruvica, the blood cancer drug it shares with Johnson & Johnson. To get a share in that drug, AbbVie shelled out $21 billion last year for Pharmacyclics, and it's predicting $7 billion for its own share of peak sales, $12 billion overall. That's quite a stretch from its current $1 billion or so.

Venetoclax works by blocking BCL-2, a protein that prevents self-destruction of cancerous cells, while Imbruvica is a Bruton's tyrosine kinase inhibitor. AbbVie execs have said that the two mechanisms are complementary, and they see the combo working not only in CLL but in other blood cancers. Venetoclax could not only boost Imbruvica, but vice versa, they say.

AbbVie CEO Richard Gonzalez

That, in turn, would mean a new push from AbbVie's sales operation, executives there have said. Roche has the U.S. marketing rights to venetoclax, but to make sure doctors get the picture on the new med and its use with Imbruvica, AbbVie expects to invite more reps to the party down the road. "We would anticipate that we would add more people in order to fill that need for capacity," AbbVie CEO Richard Gonzalez said when the Pharmacyclics deal was announced.

In the meantime, venetoclax will have plenty of competition in CLL. There's Gilead Sciences' Zydelig (idelalisib), a head-to-head Imbruvica competitor, as well as Imbruvica itself. The AbbVie/J&J drug has a specific approval in patients with a 17p deletion in the U.S., while Zydelig's European label includes its use alongside Rituxan in 17p patients. Comparing the three by overall response rates in 17p patients, venetoclax could come out on top, some analysts say. But they also point out that researchers used "step-up" dosing on venetoclax to reduce the risk of tumor lysis syndrome (TLS), a serious side effect.

- get FierceBiotech's take
- see the release from Roche

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