AZ, Merck add pancreatic cancer to Lynparza’s growing use list

AstraZeneca and Merck & Co have cemented their lead in the PARP inhibitor class with FDA approval for Lynparza in pancreatic cancer, extending the drug’s use into a third type of solid tumour.

The US regulator backed  Lynparza (olaparib) for the new indication despite a close vote – which narrowly came down in favour of approval – at an FDA advisory committee meeting earlier this month.  

The US regulator has given the nod to Lynparza (olaparib) for first-line maintenance treatment of BRCA-mutated metastatic pancreatic adenocarcinoma in people who have responded to an initial chemotherapy regimen, making it the first PARP inhibitor to get the go-ahead in this type of cancer.

It also keeps AZ and Merck ahead of rivals like GlaxoSmithKline’s Zejula (niraparib), Clovis Oncology’s Rubraca (rucaparib), and Pfizer’s recently-approved Talzenna (talazoparib).

The FDA’s positive decision doesn’t come as a major surprise, as pancreatic cancer is notoriously hard to treat and the POLO trial showing Lynparza’s impact in this patient group was described as a “game changer” when the data was reported at this year’s ASCO conference in the US.

First-line chemotherapy has a notoriously poor efficacy in this setting, with most patients only surviving eight to 12 months from diagnosis despite treatment, but AZ’s drug has shown it can extend the time it takes before the cancer starts to recur.

In the POLO study, giving Lynparza after chemo extended the time to disease progression or death to 7.4 months, versus 3.8 months with placebo, which was a 47% reduction in risk.

There’s no strong signal yet on whether the drug will improve overall survival rates – which caused the narrow advisory committee vote – but that data is due next year.   

Despite advances in cancer treatment, few advances have been made in the diagnosis and treatment of pancreatic cancer over the decades.

The current treatments are surgery, chemotherapy and radiotherapy, highlighting a clear unmet medical need for more effective treatment options.

About 5% to 6% of pancreatic cancers are caused by mutations in one or both BRCA genes, changes which are more commonly associated with ovarian and breast cancer – which are already on Lynparza’s list of approved indications.

Use in ovarian and breast cancer has already put the drug firmly on course to top the $1 billion sales threshold in 2019, according to AZ.

That will add another blockbuster to its stable of new cancer drugs, alongside EGFR inhibitor Tagrisso (osimertinib) for lung cancer and immuno-oncology therapy Imfinzi (durvalumab).

Meanwhile, Lynparza could also claim approval in BRCA-mutated prostate cancer after encouraging results in phase 3 testing earlier this year, potentially adding a fourth type of tumour to the mix. AZ has previously said it thinks it will be able to grow the drug into a $2 billion-a-year brand.