Intent on fending off future Tesaro rival, AZ touts new PhIII Lynparza data

By Tracy Staton Oct 26, 2016 9:09am

AstraZeneca doesn’t want any other PARP inhibitor to steal a march on its first-to-market Lynparza. With Tesaro hoping to do just that with ovarian cancer candidate niraparib, AZ is trumpeting some new survival data on its own med.

The U.K. drug giant said Lynparza, approved on the strength of a Phase II trial, delivered even better progression-free survival results in a Phase III ovarian cancer study, dubbed SOLO-2. Median progression-free survival in Lynparza patients “substantially exceeded” that shown in the mid-stage trial, AstraZeneca said in a Wednesday release.

Details are yet to come, so we won’t know just how substantially Lynparza exceeded its previous score until the wraps are off. But Lynparza will need as much ammo as it can get as other PARP inhibitors hit the market.

In Phase II, Lynparza delivered a median progression-free survival of 11.2 months, compared with 4.3 months among placebo patients. So, beating that number would help AstraZeneca sharpen its case to prepare for Tesaro’s niraparib--which put up a 15.5-month PFS advantage in its own recently released trial.

The patient populations tested were different for the two meds, which means the numbers don’t lend themselves to direct comparisons, but doctors tend to consider them nonetheless when deciding among treatments for their patients. Lynparza's currently approved formula is a capsule, and the latest study tested a tablet form.

AstraZeneca put a $2 billion sales target on Lynparza when it was approved in December 2014--a goal that depends on new indications. In its current market--BRCA-positive patients who’ve relapsed after three rounds of chemo--Lynparza put up $98 million in first-half sales this year, up from $54 million over the same period of 2015.

Lynparza is now on the FDA’s fast track for second-line use, which would open it up to a much larger group of women. It’s also a “breakthrough” drug at the FDA in prostate cancer, and is under testing in breast cancer, among several others.

Meanwhile, Medivation (which Pfizer is buying) and Novartis each have PARP meds on their way, though neither of those is close to an ovarian cancer nod. But Medivation’s talazoparib could be a head-to-head rival for Lynparza soon enough; it’s on its way to a prostate cancer app.

The most immediate threat comes from Tesaro: It’s wrapping up its rolling submission to the FDA on niraparib, which posted a 21-month progression-free survival stat for BRCA-positive patients in a trial unveiled earlier this month at the European Society for Medical Oncology meeting. That was 15.5 months longer than the result for placebo patients.

That’s an unprecedented survival advantage, the niraparib trial’s lead author, Dr. Mansoor Raza Mirza of Copenhagen University, said at the time. "We have never seen such large benefits in progression-free survival in recurrent ovarian cancer,” he said.

The Tesaro med also performed--albeit in a less-impressive way--in patients who didn’t test positive for the BRCA mutation. The company says it’s going to go for an FDA approval to treat patients regardless of their BRCA status.

AstraZeneca is testing Lynparza in BRCA-negative patients, too, and no wonder--the BRCA-positive group is just 10% to 15% of ovarian cancer patients. But in the meantime, AZ is happy to tout the SOLO-2 data.

“We are pleased with the robust improvement in progression-free survival demonstrated by Lynparza in the SOLO-2 trial," EVP Sean Bohen said in Wednesday's statement. "We remain committed to investigating the full potential of Lynparza, both as monotherapy and in combinations, and to identifying all patients who may benefit from this important medicine.”

Cancer Tesaro