The US Food and Drug Administration has granted accelerated approval to GSK's Jemperli (dostarlimab) as the first and only immunotherapy for adults with a specific type of locally advanced rectal cancer. The approval came on 19 October 2026, about four months ahead of its February 2027 target date.
This article is for general information and is not medical advice.
Who it is for
The approval covers adults with stage II or III rectal cancer that is MSI-H or dMMR, meaning the tumour has a defect in the system that repairs DNA errors, confirmed by an FDA-authorised test. GSK says about 5–10% of rectal cancers fall into this group; other estimates cited by Medical Daily put it at about 3% of locally advanced cases.
Treatment is 500 mg given by drip every three weeks for nine cycles, about six months.
The results
- In the AZUR-1 trial, 110 of 154 patients (71%) needed no further treatment, meaning no surgery, radiation or chemotherapy, after dostarlimab alone, according to The ASCO Post.
- The 12-month complete response rate was 47% by independent review (54 of 116) and 68% by investigators (98 of 144).
- No patient who responded had a recurrence after a median follow-up of about 26 months.
- An earlier study at Memorial Sloan Kettering of 50 patients found a 100% response rate.
The most common side effects were fatigue (32%), rash (22%), diarrhoea (18%) and itching (17%). Serious reactions occurred in 20% of patients.
Why it matters
Standard treatment for locally advanced rectal cancer usually combines chemotherapy, radiation and surgery, which can leave patients with long-term bowel, bladder and sexual problems, and sometimes a permanent stoma. Avoiding all three is a major change. "A fundamentally different treatment approach," said Andrea Cercek of Memorial Sloan Kettering.
Michael Sapienza of the Colorectal Cancer Alliance said "biomarker testing at diagnosis will be essential" so that eligible patients are identified. For related research, see our report on ultra-processed food and colorectal cancer.
What happens next
Because this is an accelerated approval, the FDA requires continued follow-up to confirm the benefit lasts. Reviews are also under way in Canada, Israel, Switzerland and the UK.
