AnaptysBio- and GSK-partnered immuno-oncology agent Jemperli (dostarlimab-gxly) plus chemotherapy demonstrates statistically significant and clinically meaningful improvement in progression-free survival for the treatment of primary advanced or recurrent

• Results published in The New England Journal of Medicine and presented simultaneously at ESMO Virtual Plenary and SGO Annual Meeting
• 72% and 36% reduction in the risk of disease progression or death observed in the dMMR/MSI-H population and overall patient population, respectively
• Clinically meaningful overall survival trend observed at interim analysis
• GSK is planning regulatory submissions for the first half of 2023

SAN DIEGO, March 27, 2023 (GLOBE NEWSWIRE) -- AnaptysBio, Inc. (Nasdaq: ANAB), a clinical-stage biotechnology company focused on delivering innovative immunology therapeutics, today announced that GSK has shared interim results from Part 1 of the RUBY/ENGOT-EN6/GOG3031/NSGO phase 3 trial investigating Jemperli (dostarlimab-gxly) plus standard-of-care chemotherapy (carboplatin-paclitaxel) followed by dostarlimab-gxly alone compared to chemotherapy plus placebo followed by placebo in adult patients with primary advanced or recurrent endometrial cancer. These data from GSK’s RUBY clinical trial are being shared in a European Society for Medical Oncology (ESMO) Virtual Plenary, presented at the Society of Gynecologic Oncology (SGO) Annual Meeting on Women’s Cancer (25-28 March) in Tampa, Florida and published simultaneously in The New England Journal of Medicine.

“We continue to be encouraged in the differentiated outcomes delivered by immuno-oncology antibodies discovered at AnaptysBio as GSK advances their development to treat multiple advanced solid tumors. The positive results from the RUBY trial represent a potential breakthrough for patients with primary advanced or recurrent endometrial cancer,” said Daniel Faga, interim president and chief executive officer of AnaptysBio. “There is a potential significant royalty opportunity over time to AnaptysBio from Jemperli if this indication is approved, as well as from GSK’s ongoing Phase 3 trials, including of dostarlimab in first line ovarian cancer and, in combination with cobolimab, a TIM-3 antagonist, in second line NSCLC.”

For specific details on the results of Part 1 of the RUBY trial, please reference the GSK stock-exchange announcement here. The safety and tolerability profile of dostarlimab-gxly in combination with carboplatin/paclitaxel in the RUBY phase 3 trial was generally consistent with the known safety profiles of the individual agents.

GSK stated in its press release that its “ambition is for dostarlimab to become the backbone of the Company’s ongoing immuno-oncology-based research and development program when used alone and in combination with standard of care and future novel cancer therapies, particularly for patients who currently have limited treatment options. Dostarlimab is being investigated in registrational enabling studies as monotherapy and as part of combination regimens, including in patients with recurrent or primary advanced endometrial cancer, patients with Stage III or IV non-mucinous epithelial ovarian cancer, and patients with other advanced solid tumors or metastatic cancers.”