Tesaro's Zejula rolls to No. 1 PARP position with big Q2

Tesaro's Zejula more than doubled consensus sales estimates in the second quarter.

Tesaro’s third-to-market PARP contender Zejula has only been around since April, but that’s all the time it needed to snag the No. 1 position in the space.

The ovarian cancer medication is now the U.S. market leader, having passed AstraZeneca’s Lynparza and Clovis’ Rubraca, Tesaro CEO Lonnie Moulder said on this week’s second-quarter earnings conference call. The product held a 60% piece of the pie in June, and to date more than 1,000 doctors have already written Zejula scripts. That’s more than twice the number of doctors who wrote them for Zejula’s rivals in their respective first quarters of launch, he added.

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A few reasons? First, Zejula is the only one of the PARP bunch that can be used as a maintenance therapy in patients with or without BRCA mutations; of the more than 1,500 patients that started Zejula treatment in the second quarter, only about half carried germline BRCA mutations, Moulder said. Zejula is also approved for patients in the second-line setting or later, whereas Rubraca is restricted to those who have already tried two prior therapies, and Lynparza patients need to have already tried three.

But that’s not all. Tesaro’s field team, comprising 170 representatives, “has held the market-leading share of voice in ovarian cancer” the three PARP players and Roche, which sells VEGF ovarian cancer treatment Avastin, he noted. Reimbursement coverage for the medication “has been excellent,” too, with more than 95% of lives covered for the medication across Medicare, Medicaid and private insurance.

Those efforts produced a second-quarter revenue haul that blew past consensus estimates. The $25.9 million tally more than doubled Wall Street’s $11.3 million forecast, Leerink Partners analyst Seamus Fernandez recently wrote to clients.

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But as Fernandez was quick to note, Zejula’s rivals could be quick to move up into earlier lines of therapy, challenging the Tesaro medication in the second-line setting. Zejula's survival advantage, a primary trial endpoint, came in at 15.5 months. Though not a head-to-head comparison, AstraZeneca in March unveiled a sensitivity analysis showing that, in patients who’d relapsed after platinum chemo, Lynparza could hold off recurrence by more than two years compared with placebo. And Clovis in June unveiled positive findings to support its bid for a label expansion as well.

Still, “we continue to like the company's long-term strategic positioning in the PARP inhibitor space,” Fernandez wrote, pointing to a couple of forthcoming datasets that could keep the med in the lead. Tesaro will unveil combo results at September’s European Society for Medical Oncology meeting, and front-line monotherapy data should be along in 2019, he said.

Editor's note: This story was updated to clarify AstraZeneca's Lynparza survival advantage as the result of a sensitivity analysis of trial data, rather than data collected for a primary trial endpoint.