TL;DR
The FDA granted accelerated approval for Jemperli (dostarlimab-gxly) alone in adults with previously untreated stage II or III locally advanced rectal cancer that is dMMR or MSI-H. In interim results from a 154-person study, nearly three-fourths had not needed surgery, radiation or chemotherapy after more than two years of median follow-up; longer monitoring is required to establish lasting benefit.
The U.S. Food and Drug Administration on October 19, 2026, granted accelerated approval for Jemperli (dostarlimab-gxly) as a stand-alone treatment for some adults with previously untreated stage II or III locally advanced rectal cancer. The approval applies only when a tumor is mismatch repair deficient (dMMR) or microsatellite instability-high (MSI-H), and may give eligible patients an option to avoid chemotherapy, radiation and surgery; whether the benefits last remains under study.
The FDA based its decision on interim results from AZUR-1, a phase 2 study of 154 patients with previously untreated dMMR or MSI-H locally advanced rectal cancer. Participants received up to nine doses of Jemperli, administered every three weeks over six months. After a median follow-up of more than two years, almost three-fourths had not needed surgery, radiation or chemotherapy, according to the FDA. That finding describes treatment received by patients during the study; it does not establish that every patient can safely forgo those treatments or that cancer will not return.
The FDA says Jemperli is intended for adults whose cancer has grown into nearby tissue or spread to nearby lymph nodes, but has not spread to distant organs. A tumor must be identified as dMMR or MSI-H through an FDA-authorized test. The agency cited published estimates that these features occur in about 3% of locally advanced rectal cancers, making the newly approved use relevant to a limited subset of patients rather than everyone with rectal cancer.
Jemperli blocks PD-1, a protein on immune cells that cancer cells can use to reduce an immune response. dMMR and MSI-H tumors have impaired DNA error correction and accumulate changes that may make them more recognizable to the immune system. The FDA warns that treatment can prompt the immune system to attack healthy organs and tissues; these reactions can be severe or fatal. Side effects reported in at least 15% of patients treated for this type of rectal cancer included fatigue, rash, diarrhea and itching.
A New Option Before Standard Treatment
For eligible patients, the approval creates a treatment choice that could change the usual sequence of care. The FDA says people with locally advanced rectal cancer often receive chemotherapy and radiation before surgery. Those treatments can affect bowel, urinary and sexual function, as well as fertility. Surgery also carries risks, including serious complications involving healing or leaks where the bowel is reconnected; some patients need a permanent colostomy.
The potential to avoid these interventions matters because their effects can continue after cancer treatment ends. But the approval is not a recommendation for all patients to skip standard care. The evidence is preliminary, the eligible tumor type is uncommon, and decisions about treatment require discussion between patients and their oncology teams, including consideration of the risks of immunotherapy and the uncertainties around long-term outcomes.
As an affiliate, we earn on qualifying purchases.
How the Evidence Supports Approval
The FDA granted accelerated approval, a pathway that allows certain drugs to reach patients based on evidence that a treatment may offer a meaningful benefit, while further study is needed to verify lasting clinical benefit. The agency said the application received Priority Review and that Jemperli had Breakthrough Therapy designation for this cancer type. It also said the review was completed nearly four months ahead of schedule; that timing does not change the need for follow-up evidence.
A separate, earlier study at Memorial Sloan Kettering Cancer Center evaluated Jemperli alone in 50 patients with previously untreated dMMR or MSI-H locally advanced rectal cancer. The FDA reported that none had detectable signs of cancer after treatment and that 93% maintained that status for at least 12 months. Among 27 patients followed for at least three years, one had a recurrence in the same area. These findings provide additional context, but they came from a separate study and do not replace the follow-up required for the approval.
“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.”
— Kyle Diamantas, acting FDA commissioner
Durability and Recurrence Need Monitoring
The AZUR-1 results are interim findings. The FDA says continued monitoring is needed to determine how long responses last and how often cancer returns. The study result that almost three-fourths had not needed surgery, radiation or chemotherapy after a median follow-up of more than two years does not by itself show that all those patients remain cancer-free or will never need additional treatment.
The FDA has not provided, in its announcement, a final estimate of long-term outcomes for AZUR-1 or a definitive comparison with standard treatment. It also remains important to identify which patients are suitable for this approach. The drug’s immune-related reactions can affect healthy organs and may be serious or fatal, so the balance of risks and benefits is a patient-specific clinical decision.
Further Study and Patient Follow-Up
GSK, the approval holder, must continue following patients to provide evidence that the responses translate into lasting clinical benefit. The FDA’s accelerated approval is conditional on that confirmatory evidence; the announcement does not specify a completion date for the follow-up or when updated results will be available.
Patients considering the treatment will need testing to establish whether their tumor is dMMR or MSI-H and a discussion with their care team about the evidence, possible immune-related harms and other treatment options. The next major development will be longer-term study results showing how durable responses are and how frequently patients require further treatment or experience recurrence.
Key Questions
Who is eligible for the newly approved use of Jemperli?
The approval covers adults with previously untreated stage II or stage III locally advanced rectal cancer whose tumors test dMMR or MSI-H using an FDA-authorized test. It does not apply to all rectal cancers.
Does the approval mean patients can skip surgery, radiation and chemotherapy?
No. Study results suggest that some patients may avoid those treatments, but the evidence is interim and does not establish that every eligible patient can safely do so. Treatment choices should be made with an oncology team.
What did the AZUR-1 study find?
In the phase 2 study of 154 patients, almost three-fourths had not needed surgery, radiation or chemotherapy after a median follow-up of more than two years. The FDA says longer follow-up is needed to assess response duration and recurrence.
What are the known risks of Jemperli?
The FDA warns that Jemperli can cause the immune system to attack healthy organs and tissues, with reactions that may be severe or fatal. Reported common side effects for this cancer use included fatigue, rash, diarrhea and itching.
Why is the approval accelerated?
The FDA granted accelerated approval based on interim evidence, while requiring GSK to continue following patients to confirm whether responses lead to lasting clinical benefit.
Source: primary
