Genentech: FDA grants Priority Review for Tecentriq plus chemotherapy in stage III dMMR/MSI‑H colon cancer
- Phase III ATOMIC showed Tecentriq plus FOLFOX6 reduced the risk of disease recurrence or death by 50% versus chemotherapy alone.
- 36‑month disease‑free survival was 86% with Tecentriq+FOLFOX6 versus 76% with FOLFOX6 alone.
- FDA has granted Priority Review of the supplemental BLA with a target action date of October 9, 2026.
- ATOMIC (A021502, NCT02912559) enrolled 712 patients and was sponsored by the NCI and conducted by the Alliance in partnership with Genentech and AIO.
Regulatory status
FDA accepted Genentech's supplemental Biologics License Application for adjuvant atezolizumab (Tecentriq and Tecentriq Hybreza) in combination with chemotherapy for stage III deficient DNA mismatch repair (dMMR) or microsatellite instability‑high (MSI‑H) colon cancer and granted Priority Review. The agency is expected to issue a decision by October 9, 2026.
Key trial results
The filing is supported by the Phase III ATOMIC study, which reported a 50% reduction in the risk of disease recurrence or death when Tecentriq was added to standard FOLFOX6 chemotherapy versus FOLFOX6 alone. The 36‑month disease‑free survival was 86% with the combination versus 76% with chemotherapy alone. The safety profile was consistent with prior Tecentriq and FOLFOX6 data.
Study design and selection
ATOMIC (A021502, NCT02912559) randomized 712 patients 1:1 to receive FOLFOX6 plus Tecentriq for 12 cycles followed by 13 cycles of Tecentriq monotherapy, or FOLFOX6 alone for 12 cycles. dMMR status was determined by immunohistochemistry tests such as the VENTANA MMR RxDx Panel. The primary endpoint was disease‑free survival.
Clinical context
Colon cancer affects over one million people annually worldwide; roughly 30% of stage III patients relapse within five years. Approximately 15% of colon tumors are dMMR/MSI‑H, a subset with higher mutation rates that may respond to immunotherapy, underpinning the rationale for adjuvant PD‑L1 inhibition in this population.
Source: Genentech
