“100% Successful” Cancer Drug Gets Landmark FDA Approval

The cancer treatment landscape is abuzz with hope as dostarlimab (brand name Jemperli) takes a significant step toward wider availability. This promising immunotherapy, developed by GlaxoSmithKline (GSK), has received a Breakthrough Therapy Designation from the U.S. Food and Drug Administration (FDA).

This programmed death receptor-1 (PD-1)-blocking antibody achieved an unprecedented 100% clinical complete response rate in patients with locally advanced dMMR/MSI-H rectal cancer. Remarkably, the treatment eradicated tumors without requiring surgery, radiation, or chemotherapy—options that often lead to severe long-term side effects such as infertility and incontinence.

The trials, conducted at Memorial Sloan Kettering Cancer Center, initially reported success in 24 patients and later expanded to include 42 participants. According to MSK gastrointestinal oncologist Andrea Cercek, all treated patients remain cancer-free, with the longest success stories now extending up to four years. Side effects have been described as mild and well-tolerated, further enhancing the treatment’s appeal.

The FDA’s Breakthrough Therapy Designation is reserved for innovative treatments addressing serious medical conditions with no comparable alternatives. Of the 1,516 requests for this designation as of mid-2024, only 587 have been granted, underscoring dostarlimab’s potential significance. This is the drug’s second FDA recognition; it received a Fast Track designation in January 2023.

Hesham Abdullah, GSK’s Senior Vice President of Research and Development, emphasized the transformative impact this treatment could have:
“Today’s designation, which is based on the unprecedented 100% clinical complete response rate of dostarlimab reported to date, supports a path to help change the treatment paradigm for patients with locally advanced dMMR/MSI-H rectal cancer, who face long-term adverse quality-of-life effects.”

Dostarlimab’s success offers hope to thousands of patients diagnosed with rectal cancer each year. In the United States alone, approximately 46,220 people are affected annually, with up to 10% of cases classified as dMMR/MSI-H cancers. If dostarlimab proves successful in further trials, it could reduce treatment timelines by about three years compared to traditional drug approval pathways.

The drug’s ability to eliminate tumors without invasive treatments signifies a paradigm shift in oncology. By targeting the molecular mechanisms of cancer while minimizing harm to the body, dostarlimab could redefine standards for immunotherapy in oncology.

While the clinical trial results have been nothing short of extraordinary, dostarlimab will undergo additional rigorous testing under the FDA’s expedited review process. This includes further evaluation of its long-term efficacy, safety profile, and broader applicability.

Groundbreaking trial results regarding dostarlimab were published in The New England Journal of Medicine.