Tesaro's Zejula quickly gaining in PARP market
- The U.S. launch of Tesaro, Inc.'s PARP inhibitor Zejula (niraparib) for the treatment of several types of ovarian cancer is under way, with more than 1,500 patient starts in the second quarter and more than a thousand prescribers since launch. Sales were $25.9 million in the second quarter, making up 88% of the company's total revenues.
- The U.S. launch of Zejula and the European launch of Varuby (oral rolapitant) for the prevention of chemotherapy-induced nausea and vomiting are the first two of Tesaro's four planned launches for 2017. A Varubi (IV rolapitant) launch is also planned for the U.S. before the end of 2017.
- Zejula is waiting on marketing approval in the EU, and the company is hoping to launch in European markets by the end of 2017. More than 200 patients have enrolled in the expanded access program across nine countries in Europe.
"The initial Zejula launch is going very well by all measures," said Leon Moulder, Tesaro co-founder and CEO in a second quarter conference call. "There is also a significant interest in our European expanded access program for niraparib, and we anticipate the European launch of Zejula by year-end."
It is a competitive market with three PARP inhibitors, but Zejula seems to be growing rapidly: of the monthly PARP inhibitor-treated recurrent ovarian cancer patients in the U.S., around 60% were treated with Zejula in June 2017, ten weeks after launch. The remaining 40% is split between Clovis Oncology's Rubraca (rucaparib) and AstraZeneca's Lynparza (olaparib).
Lynparza, which has been on the market for a few years, had sales of $50 million for the quarter, reported AstraZeneca — although sales were down 19% due to the increased competition.
Moulder sees Zejula as holding out strongly against the competitor PARP inhibitors, based on the strength of its data, and its once-daily dosing: "We have the first broad indication for maintenance treatment in recurrent ovarian cancer and have established really a new paradigm in a short period of time. We have a drug that has data that's unsurpassed. There are no data points in the primary analyses of any other data sets that exceed the benefit provided from our primary endpoint analyses across all populations."
It may also have cost advantages, as the Jefferies analysts point out. While Zejula is priced at around $14,750 for the highest (300 mg) dose (monthly WAC), compared with $13,740 for Rubraca and $12,583 for Lynparza, 40-50% of patients are likely to reduce their dose to 200 mg ($9,833) and 25% to 100 mg ($4,917).
The prescribers for Zejula are evenly split between hospitals and clinics, and around half of patients are gBRCA mutation carriers.
"We would anticipate over time, we'll have more patients that do not have a BRCA mutation. But the early use is about 50-50" said Moulder.
Tesaro has licensed Zejula to Takeda in Japan, Australia, Russia, South Korea and Taiwan, and, according to CFO Timothy Pearson, the company expects to recognize the majority of the $100 million upfront payment in the third quarter.
The Phase 3 PRIMA trial, looking at Zejula in first-line ovarian cancer, is ongoing, with progression-free survival as a primary endpoint.
"We believe the treatment benefits of niraparib monotherapy can be further expanded to the frontline ovarian cancer setting, and we intend to establish our foothold there with PRIMA," said Mary Lynne Hedley, co-founder, president, COO and director. "The expansion of that strategy will include the initiation in the first quarter next year of our combination study which accommodates the use of bevacizumab, an agent currently approved in Europe for frontline ovarian cancer, and also assesses combination treatment with an anti-PD-1 antibody. Enrollment in this trial is preceding quite well, and we currently anticipate data readout in 2019."
For patients with recurrent disease, the Phase 1/2 ANANOVA trial, currently ongoing, is assessing the combination of Zejula and Avastin (bevacizumab), with progression-free survival as an endpoint. The combination also has potential in colorectal cancer and glioblastoma multiforme. Updated data will be released in September 2017.
The Phase 1/2 TAPACIO study, in patients with triple-negative breast cancer (TNBC) or recurrent, platinum-resistant ovarian cancer, combines Zejula with Keytruda (pembrolizumab). The combination may also have potential in other cancers sensitive to PD-1 therapeutics, such as lung, bladder and head and neck cancer.
"Stage I of the expansion study includes two cohorts, one each for patients with TNBC and platinum-resistant ovarian cancer, and is fully enrolled with approximately 24 patients in each cohort," said Hedley.
Tesaro has plans to move Zejula into development in non-small cell lung cancer, beginning with a Phase 1 trial of Zejula in combination with Tesaro's PD-1 inhibitor TSR-042, and a Phase 2 trial of Zejula monotherapy.
- Tesaro Statement
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