Regeneron Reported Positive Ubamatamab Cancer Trial Data
The investigational drug showed promise in treating patients with recurrent low-grade serous ovarian cancer.
Updated on Oct. 1, 2026 in Cancer
Regeneron Pharmaceuticals has reported new trial results for its investigational drug, ubamatamab, in patients with heavily pre-treated low-grade serous ovarian cancer. The company plans to advance the drug into a Phase 3 clinical trial following promising initial efficacy metrics.
Why it matters
Low-grade serous ovarian cancer is a rare variant that typically shows limited response to standard chemotherapy, leaving patients with few effective treatment options. The development of targeted therapies like ubamatamab aims to provide a new therapeutic pathway for this specific malignancy.
In the 800 mg treatment arm, patients achieved an objective response rate of 73% and a median progression-free survival of 11 months. The study also noted that 90% of all trial participants experienced cytokine release syndrome.
The players
Regeneron Pharmaceuticals
This biotechnology company is headquartered in Tarrytown, New York, and focuses on the discovery and development of medicines for serious diseases.
U.S. Food and Drug Administration
This federal agency is responsible for protecting public health by ensuring the safety, efficacy, and security of human and veterinary drugs.
The details
Ubamatamab functions as a MUC16xCD3 bispecific antibody, designed to link MUC16 on cancer cells to CD3-expressing T cells for an immune-mediated attack. While one patient discontinued the trial due to a stroke, the company reported serious treatment-emergent adverse events in 21% of the 19 participants.
Timeline
October 1, 2026: Regeneron announced initial clinical trial results for ubamatamab.
The Big Picture
This trial follows the broader industry pattern of utilizing bispecific antibody platforms to redirect immune cells against solid tumor markers. The move marks a strategic expansion in the development of bispecific T-cell engager therapies for patients with treatment-resistant cancers.
Patients with recurring, pre-treated low-grade serous ovarian cancer may eventually gain access to a new treatment option that works differently than traditional chemotherapy. Those interested should consult their oncologist about clinical trial availability as the drug moves into larger phases of testing.
The takeaway
The successful trial results represent a shift toward specialized immunotherapy for rare ovarian cancer variants. Patients should remain in close contact with their medical teams to track if this therapy becomes available through future expanded access or wider clinical trials.
What happens next
Regeneron will engage in regulatory discussions with the U.S. Food and Drug Administration in the coming months regarding the trial data and the design of the upcoming Phase 3 confirmatory study.
Further reading
For more information on current treatment landscapes, explore the Cancer research section.
