The U.S. Food and Drug Administration on October 19, 2026 granted accelerated approval for a new use of the immunotherapy Jemperli (dostarlimab-gxly) that may allow some patients with locally advanced rectal cancer to avoid chemotherapy, radiation and surgery, according to the official release. The approval targets adults with previously untreated stage II or stage III disease whose tumors carry a specific DNA repair defect, a group the agency says makes up roughly 3% of locally advanced rectal cancers.

What the Approval Covers

Today's approval is for Jemperli used alone in adults with previously untreated stage II or stage III locally advanced rectal cancer, according to the FDA. At these stages, the cancer has grown into nearby tissue or reached nearby lymph nodes but has not spread to distant organs. To be eligible, patients' tumors must be mismatch repair deficient (dMMR) or microsatellite instability-high (MSI-H), as determined by an FDA-authorized test, and the agency notes that published estimates suggest approximately 3% of locally advanced rectal cancers fall into this category.

Both dMMR and MSI-H describe a defect in the way cancer cells correct errors when copying their DNA, the FDA explains. Normally, a built-in repair system catches and fixes these mistakes; when that system fails, errors accumulate and create proteins the immune system can recognize, making these tumors particularly vulnerable to immunotherapy. Jemperli works by targeting a protein called PD-1 on immune cells, blocking a signal cancer cells use to shield themselves from immune attack.

Standard treatment for locally advanced rectal cancer typically involves chemotherapy and radiation before surgery, which the FDA says can affect bowel, urinary and sexual function, as well as fertility. Surgery itself carries risks of serious, sometimes life-threatening complications, including poor healing and leaks where the bowel is reconnected, and in some patients results in a permanent colostomy.

The Trial Data Behind the Decision

The FDA based its decision on interim results from AZUR-1 (NCT05723562), a phase 2 study evaluating Jemperli alone in 154 patients with previously untreated dMMR or MSI-H locally advanced rectal cancer. In the study, patients received up to nine doses of Jemperli, given every 3 weeks over 6 months. After a median follow-up of more than 2 years — meaning at least half of patients had been monitored for that long — almost three-fourths of patients had not needed surgery, radiotherapy or chemotherapy, according to the FDA.

An earlier study at Memorial Sloan Kettering Cancer Center (NCT04165772) evaluated Jemperli alone in 50 patients with previously untreated dMMR or MSI-H locally advanced rectal cancer. None of the patients had detectable signs of cancer after Jemperli treatment, and nearly all patients (93%) maintained that cancer-free status for at least 12 months. Of the 27 patients followed for at least 3 years, only one had their cancer return, and it recurred in the same area, the FDA release states.

The FDA cautions that longer follow-up is needed to understand the duration of response and how often the cancer returns. Because this is an accelerated approval based on interim trial results, the sponsor, GSK, must continue following patients to show these responses create lasting clinical benefit.

Headline Figures at a Glance

Safety Profile and Review Pathway

Jemperli can cause the immune system to attack healthy organs and tissues, and the FDA warns these reactions can be severe or fatal. The most common side effects, reported in at least 15% of patients treated for this type of rectal cancer, were fatigue, rash, diarrhea and itching.

The FDA granted Priority Review to the application and Breakthrough Therapy designation to Jemperli for the treatment of dMMR or MSI-H locally advanced rectal cancer. The agency states this action marks the 11th approval of a drug reviewed under the Commissioner's National Priority Voucher pilot program, which aims to help accelerate the review of therapies that address national public health priorities.

"The FDA is committed to closing the gap between scientific progress and patient access, and that commitment has to show up not just in policy, but in the pace of our work," said Acting FDA Commissioner Kyle Diamantas, J.D., according to the release. "Completing this review nearly 4 months ahead of schedule means some patients who might otherwise be preparing for surgery, radiation or chemotherapy may now have a different conversation with their doctor."

How the FDA Reviews and Approves Cancer Drugs

The FDA, an agency within the U.S. Department of Health and Human Services, is responsible for assuring the safety, effectiveness and security of human drugs, including cancer therapies, before they can be marketed in the United States. Accelerated approval is a regulatory pathway that allows the agency to approve a drug based on an interim measure of effect, known as a surrogate endpoint, rather than waiting for complete long-term data, with the requirement that the drug's sponsor continue studying patients to confirm the treatment provides durable clinical benefit.

Priority Review and Breakthrough Therapy designations, both applied to Jemperli for this indication, are tools the FDA uses to speed the evaluation of drugs intended to treat serious conditions and that show potential to offer major improvements over existing options. The National Priority Voucher pilot program referenced in this release is a separate initiative aimed at accelerating reviews for therapies addressing national public health priorities, and this is the 11th drug approval to come through that program, according to the FDA.

This approval adds to a string of recent FDA oncology and drug actions reported this year, including the agency's first-of-its-kind treatment for chronic hepatitis B, underscoring continued agency activity around accelerated and priority drug reviews even as broader launch prices for new drugs have surged in recent years.

Frequently asked questions

Who is eligible for this new use of Jemperli?

Adults with previously untreated stage II or stage III locally advanced rectal cancer whose tumors are confirmed as mismatch repair deficient (dMMR) or microsatellite instability-high (MSI-H) by an FDA-authorized test. The FDA estimates approximately 3% of locally advanced rectal cancers meet this genetic criteria.

What treatments might eligible patients avoid?

In the AZUR-1 trial, almost three-fourths of 154 patients had not needed surgery, radiotherapy or chemotherapy after a median follow-up of more than 2 years. Standard treatment otherwise typically involves chemotherapy and radiation before surgery, which can affect bowel, urinary and sexual function.

What happens next for patients and the drug's approval status?

Because this is an accelerated approval based on interim trial results, GSK, the drug's sponsor, must continue following patients to confirm the responses translate into lasting clinical benefit. The FDA has said longer follow-up is needed to understand how long responses last and how often the cancer returns.