GSK's Jemperli Delivers 76% Complete Response in MSI-H/dMMR Rectal Cancer
GSK sits 19% above its 52-week low of $42.845.
Summary
Interim AZUR-1 data show 76% of evaluable MSI-H/dMMR locally advanced rectal cancer patients (110/144) had a complete response to Jemperli alone, with no recurrences after more than two years. The data underpinned the 19 October US approval; the independent-review cCR12 endpoint is still maturing at 47%.
Key Events · Product Development and Regulatory · GSK
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AZUR-1 Shows 76% Complete Response
In an exploratory analysis, 76% of evaluable patients (110/144; 95% CI 69%-83%) achieved a complete response to dostarlimab monotherapy, including 68% (98/144) with a sustained clinical complete response of at least 12 months by investigator assessment.
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Primary Endpoint Still Maturing
By independent central review, the registrational endpoint of cCR12 stood at 47% (54/116; 95% CI 37%-56%) at analysis, with 38 additional patients already in response but not yet at the 12-month timepoint.
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No Recurrences After Two Years
Among responders, no disease recurrences have been reported after a median follow-up of more than two years, supporting an organ-preservation approach that avoids chemotherapy, radiation and surgery.
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Safety Consistent With Prior Profile
Serious adverse reactions occurred in 20% of patients and 3% permanently discontinued; the most common reactions were fatigue (32%), rash (22%), diarrhoea (18%) and pruritus (17%).
Analysis · GSK · Life Sciences
What matters here is the first full look at the AZUR-1 dataset behind Jemperli's 19 October US approval in locally advanced rectal cancer. A 76% complete response rate, with no recurrences after more than two years of follow-up, supports an organ-preservation approach that could let eligible patients skip chemotherapy, radiation and surgery — a genuine differentiator versus standard treatment. The caveat: the registrational primary endpoint, cCR12 by independent central review, sits at only 47% (54/116) so far, with 38 more patients still short of the 12-month assessment, so the headline number will settle lower as data mature. Near-term revenue is small for a company of GSK's size — MSI-H/dMMR accounts for only 5-10% of rectal cancers — but the data strengthen the oncology franchise story and the case for Jemperli across colorectal and gynaecologic settings.
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