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The US Food and Drug Administration granted accelerated approval on 19 October 2026 for Jemperli in a defined group of adults with locally advanced rectal cancer. The decision rests on evidence of tumour response, with lasting clinical benefit still needing confirmation.
The decision concerns Jemperli, also called dostarlimab, used on its own. It is a new use for a medicine that already had US authorisation for certain other cancers, including previously treated advanced solid tumours with a particular biological characteristic.
Who is covered?
According to the FDA’s announcement, the new US approval covers adults with previously untreated stage II or III locally advanced rectal cancer whose tumours are microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR), as determined by an FDA-authorised test.
These biological markers concern faults in the machinery that repairs errors when cells copy their DNA. They help identify the particular patient group studied. The approval does not apply to every person with bowel cancer. In this setting, locally advanced means cancer has reached nearby tissue or lymph nodes without spreading to distant organs.
What does accelerated approval mean?
The FDA’s accelerated-approval pathway allows earlier US approval for serious conditions using an outcome considered likely to predict clinical benefit. The manufacturer must still establish the anticipated lasting benefit through further study. FDA procedures can lead to withdrawal if that benefit is not confirmed.
For this use of Jemperli, the approval rests on sustained clinical complete response for 12 months. Longer follow-up remains important because the long-term risk of relapse is uncertain.
How should the trial results be read?
The main AZUR-1 study enrolled 154 patients. It was a phase II, open-label, single-arm study: there was no randomly assigned comparison group receiving another treatment.
GSK reports that independent central reviewers found a clinical complete response sustained for 12 months in 54 of 116 evaluable patients, or 47%. Investigators assessing patients reported that outcome in 98 of 144 evaluable patients, or 68%. Those figures come from different assessments and denominators.
Some participants who had achieved a response had not yet completed 12 months of follow-up. A clinical complete response describes the absence of detectable cancer on the assessments used. It cannot establish that cancer will never return. The trial therefore offers evidence of a potential way for some eligible patients to avoid chemotherapy, radiation and surgery, while leaving important longer-term questions open.
What about safety?
GSK reports serious adverse reactions in 20% of study participants. Common reactions included fatigue, rash, diarrhoea and itching. The FDA also warns that Jemperli can cause the immune system to attack healthy organs and tissues, with reactions that can be severe or fatal.
What does this establish for South Africa?
A US decision does not itself establish South African authorisation, availability or funding. SAHPRA’s published guidance sets out a separate South African medicine-registration process. It can also consider exceptional access to unregistered medicines through Section 21, involving a separate application and authorisation; approval is not automatic.
The sources reviewed for this explainer do not establish South African authorisation for this new use, local stock, price or medical-scheme coverage. Eligibility for the US indication and access in South Africa are separate questions.
