GSK enters PARP space with TESARO acquisition

GSK has announced that it will acquire US-based oncology specialist TESARO for $5.1 billion, gaining access to its PARP inhibitor Zejula (niraparib).

Previously, several other firms were rumoured to be interested in buying the company, including Roche.

Zejula is an oral poly ADP ribose polymerase (PARP) inhibitor currently approved for use in the US and Europe as a treatment for adult patients with recurrent ovarian cancer who are in response to platinum-based chemotherapy, regardless of BRCA mutation or biomarker status.

The deal will help GSK compete in the PARP space with companies like AstraZeneca – who have been TESARO’s main rival with their own ovarian cancer drug Lynparza (olaparib) – and Clovis Oncology’s Rubraca (rucaparib).

“Our strong belief is that PARP inhibitors are important medicines that have been under appreciated in terms of the impact they can have on cancer patients,” said Hal Barron, chief scientific officer and president, R&D, GSK.

“We are optimistic that Zejula will demonstrate benefit in patients with ovarian cancer beyond those who are BRCA-positive as front-line treatment.”

Zejula is currently in trials to assess its potential as a monotherapy and in combinations for first line maintenance treatment of ovarian cancer. These trials are evaluating the potential benefit of the drug in patients who carry gBRCA mutations as well as the larger population of patients without gBRCA mutations whose tumours are HRD-positive and HRD-negative. Results from the first of these studies are expected in the second half of 2019.

The drug is also being investigated for use as a possible treatment in lung, breast, bladder and prostate cancer, both as a monotherapy and in combination with other medicines, including with TESARO’s own anti-PD-1 antibody (dostarlimab, formerly known as TSR-042) and Roche’s Tecentriq (atezolizumab).

TESARO has several other oncology drugs in its pipeline including antibodies directed against PD-1, TIM-3 and LAG-3 targets.

“The acquisition of TESARO will strengthen our pharmaceuticals business by accelerating the build of our oncology pipeline and commercial footprint, along with providing access to new scientific capabilities,” said Emma Walmsley, GSK’s CEO. “This combination will support our aim to deliver long-term sustainable growth and is consistent with our capital allocation priorities. We look forward to working with TESARO’s talented team to bring valuable new medicines to patients.”

The announcement comes in the wake of two consumer healthcare deals for GSK, which will have helped finance the acquisition. Last week the company sold the North American distribution rights to five consumer healthcare brands – PanOxyl, Sarna, Zeasorb, Desenex, and Mineral Ice – to Crown Laboratories, and yesterday it announced it would be divesting Horlicks and other OTC nutrition brands to Unilever while merging GSK India with Hindustan Unilever Limited (HUL).