Adjuvant atezolizumab in Japanese patients with resected stage IB-IIIA non-small cell lung cancer (IMpower010).

The global phase 3 IMpower010 study evaluated adjuvant atezolizumab versus best supportive care (BSC) following platinum-based chemotherapy in patients with resected stage IB-IIIA non-small cell lung cancer (NSCLC). Here, we report a subgroup analysis in patients enrolled in Japan. Eligible patients had complete resection of histologically or cytologically confirmed stage IB (tumors ≥4 cm)-IIIA NSCLC. Upon completing 1-4 cycles of adjuvant cisplatin-based chemotherapy, patients were randomized 1:1 to receive atezolizumab (fixed dose of 1200 mg every 21 days; 16 cycles or 1 year) or BSC. The primary endpoint of the global IMpower010 study was investigator-assessed disease-free survival, tested hierarchically first in patients with stage II-IIIA NSCLC whose tumors expressed programmed death-ligand 1 (PD-L1) on ≥1% of tumor cells, then in all randomized patients with stage II-IIIA NSCLC, and finally in the intention-to-treat (ITT) population (stage IB-IIIA NSCLC). Safety was evaluated in all patients who received atezolizumab or BSC. The study comprised 149 enrolled patients in three populations: ITT (n = 117; atezolizumab, n = 59; BSC, n = 58), all-randomized stage II-IIIA (n = 113; atezolizumab, n = 56; BSC, n = 57), and PD-L1 tumor cells ≥1% stage II-IIIA (n = 74; atezolizumab, n = 41; BSC, n = 33). At the data cutoff date (January 21, 2021), a trend toward disease-free survival improvement with atezolizumab vs BSC was observed in the PD-L1 tumor cells ≥1% stage II-IIIA (unstratified hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.25-1.08), all-randomized stage II-IIIA (unstratified HR, 0.62; 95% CI, 0.35-1.11), and ITT (unstratified HR, 0.61; 95% CI, 0.34-1.10) populations. Atezolizumab-related grade 3/4 adverse events occurred in 16% of patients; no treatment-related grade 5 events occurred. Adjuvant atezolizumab showed disease-free survival improvement and a tolerable toxicity profile in Japanese patients in IMpower010, consistent with the global study results.

Subgroup analysis of Japanese patients in a phase III randomized, controlled study of neoadjuvant atezolizumab or placebo, combined with nab-paclitaxel and anthracycline-based chemotherapy in early triple-negative breast cancer (IMpassion031).

BACKGROUND: In the global phase III IMpassion031 study, neoadjuvant atezolizumab plus nab-paclitaxel/anthracycline-based chemotherapy improved pathological complete response in patients with early stage triple-negative breast cancer. Here, we report primary analysis results from a subgroup of Japanese patients. METHODS: Patients with histologically documented, previously untreated, stage cT2-cT4, cN0-cN3, cM0 triple-negative breast cancer were randomized 1:1 to receive intravenous atezolizumab 840 mg or placebo every 2 weeks in combination with chemotherapy consisting of nab-paclitaxel intravenous 125 mg/m2 once a week, followed by doxorubicin intravenous 60 mg/m2 and cyclophosphamide intravenous 600 mg/m2 every 2 weeks. Patients then underwent surgery. Pathological complete response (ypT0/is ypN0) in the intention-to-treat and PD-L1-positive (≥1% PD-L1-expressing tumor-infiltrating immune cells) populations were co-primary endpoints. RESULTS: This subanalysis (data cutoff: 3 April 2020) included 36 patients from Japan (intention-to-treat; atezolizumab arm, n = 17; placebo arm, n = 19). Pathological complete response occurred in 41% (n = 7; 95% confidence interval, 18-67) of patients in the atezolizumab arm and 37% (n = 7; 95% confidence interval, 16-62) in the placebo arm. In the PD-L1-positive population, pathological complete response occurred in 50% (n = 5; 95% confidence interval, 19-81) of patients in the atezolizumab arm and 45% (n = 5; 95% confidence interval, 17-77) in the placebo arm. Treatment-related grade 3-4 adverse events occurred in 71% and 68% of patients in the respective arms. CONCLUSION: Atezolizumab added to neoadjuvant chemotherapy numerically improved pathological complete response versus placebo in this small exploratory analysis of Japanese patients with early stage triple-negative breast cancer, a trend directionally consistent with the global study results. No new safety signals were identified.