The US Food and Drug Administration (FDA) has approved intravenous and subcutaneous formulations of atezolizumab in combination with fluoropyrimidine- and oxaliplatin-based chemotherapy for adjuvant treatment of stage 3 mismatch repair–deficient (dMMR) colon cancer following complete surgical resection, according to an agency press release.
Intravenous atezolizumab (Tecentriq) was approved for adults and children aged 2 years and older. Subcutaneous atezolizumab and hyaluronidase-tqjs (Tecentriq Hybreza) was approved for adults and children aged 12 years and older weighing at least 40 kg. Both indications require stage 3 dMMR colon cancer.
The approvals were supported by ATOMIC/ML39057 (NCT02912559), a multicenter, randomized, open-label, active-controlled phase 3 trial involving 711 adults and 1 pediatric patient with resected stage 3 dMMR colon cancer and no evidence of residual lymph node involvement or metastatic disease.
Participants were randomly assigned to modified FOLFOX6 (mFOLFOX6; oxaliplatin, leucovorin, and fluorouracil) plus atezolizumab for 12 cycles, followed by atezolizumab monotherapy for 6 months, or mFOLFOX6 alone for 12 cycles.
The primary end point was investigator-assessed disease-free survival (DFS). Adding atezolizumab reduced the risk of disease recurrence or death by 50% compared with chemotherapy alone. Median DFS was not reached in either group. According to Genentech's June 2026 announcement of the ATOMIC findings, 36-month DFS was 86% with atezolizumab plus chemotherapy versus 76% with chemotherapy alone.
Genentech reported that the combination's safety profile was consistent with previous studies of atezolizumab and FOLFOX6. The FDA prescribing information includes warnings and precautions for immune-mediated adverse reactions, infusion-related reactions, complications of allogeneic hematopoietic stem-cell transplantation, and embryo-fetal toxicity.
For adults, the recommended intravenous atezolizumab dosing is 840 mg every 2 weeks, 1,200 mg every 3 weeks, or 1,680 mg every 4 weeks. Pediatric dosing is recommended at 10 mg (up to 840 mg) every 2 weeks or 15 mg (up to 1,200 mg) every 3 weeks. Treatment is administered with chemotherapy for 6 months, followed by atezolizumab monotherapy for another 6 months or until disease recurrence or unacceptable toxicity.
The subcutaneous formulation is administered as a 15 mL injection containing 1,875 mg atezolizumab and 30,000 units hyaluronidase every 3 weeks, following the same treatment schedule. Dosing has not been established for children younger than 12 years or those aged 12 years and older weighing less than 40 kg.
Both applications received priority review and were evaluated under Project Orbis, with regulatory reviews continuing in Australia, Canada, Israel, and Switzerland.
Sources
US Food and Drug Administration. FDA approves atezolizumab in combination with chemotherapy for stage III mismatch repair deficient colon cancer. Published October 8, 2026. FDA approval announcement.
Sinicrope FA, Ou FS, Arnold D, et al. Atezolizumab plus FOLFOX for stage III mismatch repair–deficient colon cancer. N Engl J Med. 2026;394(12):1155-1166. doi:10.1056/NEJMoa2507874. Full study.
Genentech. FDA grants priority review for Genentech's Tecentriq for a certain type of stage III colon cancer. Published June 10, 2026.
