2019 ASCO-SITC Symposium: Neoadjuvant Atezolizumab in NSCLC
Posted: Friday, March 8, 2019
According to research presented at the 2019 American Society of Clinical Oncology–Society for Immunotherapy of Cancer (ASCO-SITC) Clinical Immuno-Oncology Symposium (Abstract 99), neoadjuvant atezolizumab resulted in an “encouraging” major pathologic response rate in patients with resectable non–small cell lung cancer (NSCLC). In addition, preliminary data illustrated changes in the peripheral blood with immunotherapy.
“We observed significant increases in natural killer (NK) cells, CD8-positive T cells, Th1-response–related dendritic cells, and decreases in B cells after [atezolizumab],” wrote Filiz Oezkan, MD, of The Ohio State University, and colleagues.
The study enrolled 116 patients as of October 2018; 54 patients underwent follow-up through surgery, with 50 undergoing the planned procedure. The major pathologic response rate was 22% (10 of 45), excluding 5 patients with ALK or EGFR mutations. The biomarker-evaluable population consisted of 31 patients, 23 of whom had tissue PD-L1 status. Overall, 16 patients had PD-L1–positive disease. Late-activated NK cells, monocytic myeloid cells, and Th2- and Th17-response–related dendritic cells all increased in patients without a major pathologic response, whereas those with PD-L1–positive disease experienced decreases in monocytic myeloid and senescent T cells and increases in Th1-response–related dendritic cells.
Patients received 1,200 mg of atezolizumab on days 1 and 22 in 2 cycles prior to resection. A total of 15 patients experienced grade 3 or 4 adverse events, 3 of which were related to treatment. A single unrelated grade 5 event, sudden death, was recorded. PD-L1–positive cells increased in most patients following treatment with atezolizumab.
Disclosure: The study authors’ disclosure information may be found at coi.asco.org.