J&J, Pharmacyclics celebrate yet another nod for leukemia med Imbruvica

Johnson & Johnson's ($JNJ) new blood cancer drug Imbruvica (ibrutinib) is on a roll. The FDA just armed the drug with a new indication in chronic lymphocytic leukemia, adding to a series of regulatory nods.

The new use--in patients with a rare genetic abnormality--may seem like a narrow sort of victory. Only about 8% of untreated CLL patients have it. But the 17p deletion is associated with poor responses to standard CLL treatment. And that means Imbruvica, co-developed with Pharmacyclics, now has the edge on all those meds in treating 17b patients.

Up to 40% of CLL patients who failed on other meds, or whose cancer returned after previous therapy, carry that abnormal chromosome. Imbruvica's results in that group are impressive, according to a study of 17b patients who'd been treated with other therapies. The study patients who received Imbruvica saw a 75% reduction in the risk of death or cancer progression, the FDA says.

The FDA gave Imbruvica another validation Monday. The drug was approved in February for CLL treatment under the agency's accelerated approval program. Now, there's enough evidence to ratify the earlier data that showed Imbruvica benefited CLL patients, the FDA says. That means Imbruvica is officially fully approved for CLL.

Among that evidence: A head-to-head trial against GlaxoSmithKline's ($GSK) competing treatment Arzerra. In a study presented at the American Society of Clinical Oncology meeting in June, Imbruvica beat Arzerra at improving progression-free survival, overall survival and overall response rate. In that study, Imbruvica patients saw a 78% reduction in the risk of progression or death.

Imbruvica has made early strides in capturing CLL market share. It's pegged as one of the top 20 orphan drugs by 2018. But the contest is heating up, with Gilead Sciences' ($GILD) new Zydelig (idealisib) winning CLL approval in the U.S. just last week. Zydelig's FDA nod came with a black box warning, however, which could be something of a drag on its initial launch, analysts say. Meanwhile, both Zydelig and Imbruvica nabbed their first CLL approvals in Europe Friday, setting up a head-to-head battle for share.

- see the FDA release

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