The U.S. Food and Drug Administration has approved Tecentriq (atezolizumab) in combination with chemotherapy for adults and children with stage III mismatch repair-deficient (dMMR) colon cancer, following surgery.
The approval, announced October 8, covers atezolizumab paired with a fluoropyrimidine and oxaliplatin as adjuvant treatment — the additional therapy given after the primary tumour has been removed to reduce the chance of the disease returning. A subcutaneous formulation, Tecentriq Hybreza, was approved alongside the intravenous version.
The decision rests on the phase 3 ATOMIC trial, which enrolled 712 patients with completely resected stage III dMMR colon cancer. Those receiving atezolizumab plus standard chemotherapy saw a 50 per cent reduction in the risk of recurrence or death compared with chemotherapy alone, a hazard ratio of 0.50. Three-year disease-free survival stood at 86.3 per cent in the combination arm versus 76.2 per cent with chemotherapy alone, according to reports.
For the manufacturer, the decision marks a twelfth U.S. indication for Tecentriq — and, by its account, the first approved immunotherapy-based regimen in this setting. Until now, the adjuvant standard of care for stage III colon cancer had not differed by mismatch-repair status, making the approval a meaningful shift toward treatment tailored to the tumour’s biology.
Patients should note that, as with other immunotherapies, the treatment carries warnings for immune-mediated reactions and other serious side effects, and full prescribing information is available from the FDA. For a defined group of patients at high risk of recurrence, though, the approval opens a new standard of care — one aimed squarely at keeping the cancer from coming back.
