GlaxoSmithKline plc Completes acquisition of TESARO

GlaxoSmithKline plc

GlaxoSmithKline plc (LON:GSK,NYSE: GSK) today announced that it has successfully completed the acquisition of TESARO, Inc. an oncology-focused company based in Waltham, Massachusetts, for an aggregate cash consideration of approximately $5.1 billion (£4.0 billion). The transaction, which was announced on 3 December 2018, significantly strengthens GSK’s pharmaceutical business, accelerating the build of GSK’s pipeline and commercial capability in oncology.

TESARO is a commercial-stage biopharmaceutical company, with a major marketed product, Zejula (niraparib), an oral poly ADP ribose polymerase (PARP) inhibitor currently approved for use in ovarian cancer. PARP inhibitors are transforming the treatment of ovarian cancer, notably demonstrating marked clinical benefit in patients with and without germline mutations in a BRCA gene (gBRCA). Zejula is currently approved 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.

Clinical trials to assess the use of Zejula in “all-comers” patient populations, as a monotherapy and in combinations, for the significantly larger opportunity of first line maintenance treatment of ovarian cancer are also underway. These ongoing trials are evaluating the potential benefit of Zejula 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, PRIMA, are expected to be available in the second half of 2019.

GSK also believes PARP inhibitors offer significant opportunities for use in the treatment of multiple cancer types. In addition to ovarian cancer, Zejula is currently being investigated for use as a possible treatment in lung, breast 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).

In addition to Zejula and dostarlimab, TESARO has several oncology assets in its pipeline including antibodies directed against TIM-3 and LAG-3 targets.

Dr Hal Barron, Chief Scientific Officer and President, R&D, GSK, said: “Both GSK and TESARO are driven by a focus on patients and a deep desire to develop truly transformational medicines that can improve and extend their lives. The acquisition of TESARO, which we have completed today, significantly strengthens our oncology pipeline and brings new scientific capabilities and expertise that will increase the pace and scale at which we can help patients living with cancer.”

Dr Mary Lynne Hedley, President and Chief Operating Officer, TESARO, said: “This new partnership between TESARO and GSK marks an important milestone in advancing our mission of developing transformative therapies for individuals living with cancer. Together with GSK, we can accelerate and further advance TESARO’s development and commercialization initiatives and, ultimately provide more time for more patients.”

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