GSK and J&J spend billions to boost their cancer drug pipelines

Two large drugmakers announced deals today to boost their cancer drug pipelines. GlaxoSmithKline will purchase Tesaro, which sells a cancer drug known as a PARP inhibitor, for $5.1 billion, and Johnson & Johnson will work with Argenx to develop the blood cancer drug cusatuzumab in a deal worth up to $1.6 billion.

GSK is getting Tesaro’s small-molecule drug niraparib, sold as Zejula, which inhibits an enzyme involved in DNA repair called poly ADP-ribose polymerase (PARP). If cells have too much DNA damage, they will self-destruct. Some cancers, particularly breast and ovarian cancers, already have mutations in BRCA, a gene for another DNA repair system. In an effect known as synthetic lethality, blocking the PARP-mediated DNA repair in tumors that already have mutant BRCA can deal a fatal blow.

Tesaro tested its drug in women with ovarian cancer who had already undergone two or more platinum-based chemotherapy treatments. Niraparib was significantly more effective than a placebo in women with and without BRCA mutations, but the effect was particularly pronounced in people with BRCA mutations. The US Food and Drug Administration approved niraparib in March 2017 as a maintenance therapy to keep ovarian cancer at bay.

In the first three quarters of 2018, Tesaro posted only $166 million in niraparib sales, but GSK is counting on revenues to increase in the future.

At the moment, niraparib is considered a second-line maintenance therapy, meaning it’s not the first drug that oncologists turn to when treating women with ovarian cancer. Clinical trials are underway testing niraparib alone and in combination with other drugs as a first-line maintenance therapy. Niraparib is also under investigation for use in breast, lung, and prostate cancers.

GSK will face competition from AstraZeneca and Clovis Oncology, which have their own commercial PARP inhibitors called Lynparza (olaparib) and Rubraca (rucaparib), respectively.

Separately, J&J’s Cilag affiliate has signed a deal to license cusatuzumab, an anticancer antibody from the Dutch biotech Argenx.

Argenx is developing therapies for a variety of autoimmune diseases and cancers using portions of llama antibodies. Cusatuzumab, which targets a protein called CD70, is undergoing testing in Phase II trials for T-cell lymphoma and acute myeloid leukemia. J&J is paying Argenx $300 million in cash and purchasing $200 million of newly issued shares. Argenx could also receive up to $1.3 billion in future payments from J&J depending on cusatuzumab’s performance.