AACR: Clovis' Rubraca follows Lynparza's big pancreatic cancer win with phase 2 data

ATLANTA—AstraZeneca and Merck’s Lynparza earlier this year posted an unprecedented phase 3 win in the pancreatic cancer arena. Now, another drug in its class has shown some early success battling the disease, too.

Tuesday at the American Association for Cancer Research annual meeting, investigators released phase 2 data showing Clovis Oncology's PARP inhibitor, Rubraca, could spur a response among BRCA- or PALB2-mutated pancreatic cancer patients who were sensitive to platinum chemotherapy.

Researchers tested the drug in patients whose cancer hadn’t worsened after treatment with chemo, and 37% of them benefited from Rubraca therapy. After starting Rubraca treatment, patients went a median 9.1 months without their disease progressing.

While the data are “extremely preliminary” and researchers need more analysis to validate the findings, they still represent “a very exciting, kind of groundbreaking signal” that patients in this pool “might indeed respond to single-agent PARP inhibition therapy,” said lead investigator Kim Reiss Binder, M.D.

The results also point to a potentially less-toxic path forward for pancreatic cancer patients with these mutations, who have traditionally stayed on chemo long-term. The study raises what could wind up being “a new way forward” that allows patients to “switch to something which gives them their lives back, rather than continuing chemotherapy until they die,” Reiss Binder said in an interview.

RELATED: AstraZeneca, Merck's Lynparza posts pancreatic cancer win in another PARP-class first

The new results follow closely after AstraZeneca and Merck’s February announcement that their own PARP inhibitor, Lynparza, had beaten out placebo at staving off pancreatic cancer progression in patients with germline BRCA-mutated forms of the disease. The companies haven’t shared details yet, but in search of a green light in the tough-to-treat field, they're working to get results to regulators as quickly as they can.

The way Reiss Binder sees it, Rubraca's AACR data complement the Lynparza findings. “Our data is clearly much smaller and much more preliminary, but it adds to the same story—that this is potentially … a new frontier in the treatment of these specific BRCA pancreatic cancer patients,” she said.