FDA Approves Atezolizumab Plus Chemotherapy for Stage III dMMR Colon Cancer, Halving Disease-Free Survival Risk
The US Food and Drug Administration on October 8 approved atezolizumab (Tecentriq, Genentech) in combination with a fluoropyrimidine and oxaliplatin for the adjuvant treatment of adult and pediatric patients aged 2 and older with Stage III mismatch repair-deficient (dMMR) colon cancer. The subcutaneous formulation, atezolizumab and hyaluronidase-tqjs (Tecentriq Hybreza), was approved with the same chemotherapy for patients 12 and older weighing at least 40 kg.
The approval rests on the ATOMIC/ML39057 trial, in which 711 adults and one pediatric patient who had undergone complete resection were randomized 1:1 to atezolizumab plus 12 cycles of mFOLFOX6 followed by six months of atezolizumab monotherapy, or 12 cycles of mFOLFOX6 alone. The major efficacy outcome, disease-free survival, showed a hazard ratio of 0.50 (95% CI 0.35–0.73; p=0.0001) — a halving of the risk of recurrence or death — with median disease-free survival not reached in either arm.
The FDA labeling carries warnings for immune-mediated adverse reactions, infusion-related reactions, complications of stem-cell transplantation and embryo-fetal toxicity. Mismatch repair-deficient tumors are among the colon cancers most responsive to immunotherapy, making this an important addition to adjuvant options; treatment decisions rest with the patient's oncology team based on biomarker testing.
Source: GSM · USA (original Chinese edition)
Photo: 癌组织中的T细胞显微图像。Image: NIH Image Gallery, public domain
