Xtandi field force gets a staffing boost for market-share battle with Zytiga

Astellas and Medivation ($MDVN) bagged that new Xtandi approval in prostate cancer. What next? Gear up for a head-to-head with Johnson & Johnson's ($JNJ) Zytiga. And to do that, Medivation is expanding its sales force by 50%, Medical Marketing & Media reports.

With Astellas fielding 90 reps to tout Xtandi, Medivation decided to boost its team to 90 reps from 60. That's because the new label--backing Xtandi for use in patients not yet treated with chemo--opens up a new group of potential prescribers. Naturally, Medivation wants to reach them.

In a conference call about the new approval, CEO Dr. David Hung said Medivation and Astellas could previously only target urologists who deliver chemotherapy. That's only "a small segment" of the urology universe. Now that the approval nixes chemo as a prerequisite, the two partners can "target all urologists," Hung said (as quoted by MM&M).

Of course, Zytiga has a big head start in the pre-chemo setting, with that FDA nod under its belt since December 2012. But analysts give Xtandi a good shot at dominating the first-line market.

When Medivation unveiled its pre-chemo data early this year, JPMorgan analyst Geoffrey Meacham said the "impressive" stats "definitely favor the Astellas-Medivation drug." The data left "little room for debate on whether Xtandi or J&J's Zytiga will have majority market share" in that group of patients, he said.

Last week, as the FDA approval came through, the enthusiasm was undiminished. Leerink Partners' Howard Liang had already posited in an August note that Xtandi's success in the post-chemo world is a sign of things to come in pre-chemo patients.

But price could be a factor, as MM&M notes. Liang himself has said that some insurers have favored Zytiga because of the cost difference. (When Xtandi launched, it carried a $74,500 price tag, compared with Zytiga's $66,000.) For instance, in January, Blue Cross of Massachusetts put Xtandi behind Zytiga on a new step-therapy policy in prostate cancer. So, while the field reps knock on doors in urology and oncology, Astellas and Medivation will have to make their case with payers as well.

Still, there's plenty of room for both Xtandi and Zytiga to be blockbusters. Decision Resources has said that the prostate cancer market is expected to double to $9.1 billion by 2021, with Xtandi expected to hit $2.2 billion by then.

- see the MM&M story

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