nab-Paclitaxel Plus Carboplatin Induction Followed by nab-Paclitaxel Maintenance in Squamous Non-Small Cell Lung Cancer (ABOUND.sqm): A Phase 3 Randomized Clinical Trial

Abstract Purpose To evaluate maintenance nab-paclitaxel in advanced squamous non-small cell lung cancer (NSCLC). Patients and Methods Patients with treatment-naive squamous NSCLC received four 21-day cycles of nab-paclitaxel 100 mg/m2 (days 1, 8, 15) plus carboplatin AUC 6 (day 1) as induction. Patients without disease progression after induction were randomized 2:1 to maintenance nab-paclitaxel 100 mg/m2 (days 1 and 8 every 21 days) plus best supportive care (BSC) or BSC alone. The primary endpoint was progression-free survival (PFS). Secondary endpoints included safety and overall survival (OS). Results Overall, 420 patients received induction therapy; 202 (nab-paclitaxel plus BSC, 136; BSC, 66) received maintenance therapy. Enrollment was discontinued after a preplanned interim futility analysis (patients could remain in the study at investigator’s discretion). Median PFS was 3.12 (nab-paclitaxel plus BSC) vs 2.60 (BSC) months; the difference was not statistically significant (HR 0.85; 95% CI, 0.61-1.19; P=0.36). Median OS (median follow-up, 24.2 months) was 17.18 (nab-paclitaxel plus BSC) vs 12.16 (BSC) months (HR 0.70; 95% CI, 0.48-1.02; nominal P=0.07). An updated analysis (median follow-up, 28.4 months) revealed a median OS of 17.61 (nab-paclitaxel plus BSC) vs 12.16 (BSC) months (HR 0.68; 95% CI, 0.47-0.98; nominal P=0.037). The most frequent grade 3/4 TEAEs (entire study) were neutropenia (53.1% [nab-paclitaxel plus BSC] vs 50.0% [BSC]) and anemia (33.1% vs 32.3%); only peripheral neuropathy occurred in ≥ 5% of patients during maintenance (13.1%; nab-paclitaxel plus BSC). Conclusions ABOUND.sqm did not meet the primary endpoint of PFS. An updated OS analysis revealed a trend favoring nab-paclitaxel plus BSC.