Yanqiao Zhang, Jieer Ying, Liwei Wang, Shujun Yang, Rui-Hua Xu, Guanghai Dai, Mingyu Li, Damir Begic, Xianjun Yu, Jia Chen, Lin Shen, Hongming Pan, Jihui Hao, Jianming Xu, Guohong Han, and Brian Lu
327 Background: nab-P + Gem demonstrated significantly better overall survival (OS; median: 8.7 vs 6.6 mo; HR 0.72; P < 0.001) than Gem alone as first-line treatment for pts with MPC in the MPACT study. This phase II bridging study evaluated efficacy and safety of nab-P + Gem in Chinese pts with MPC. Methods: Efficacy and safety of nab-P 125 mg/m2 + Gem 1000 mg/m2 on days 1, 8, and 15 every 4 weeks was evaluated in a 3-part sequential study. In part 1, safety was examined. In part 2, efficacy was evaluated by the Simon optimal 2-stage design. If there were > 2 responses in 28 pts in stage 1 of part 2, an additional 54 pts would be treated in stage 2. The study would be completed if > 9 responses were observed. If there was an insufficient number of responses in either stage of part 2, part 3 would be triggered to compare nab-P + Gem vs Gem alone. The primary endpoint was overall response rate (ORR). Secondary endpoints included duration of response (DOR), OS, and safety. Correlation of OS and baseline neutrophil-to-lymphocyte ratio (NLR) was also analyzed. Results: Eighty-three pts were treated. Median age was 57.0 y; 19% were aged > 65 y; baseline Karnofsky performance status was 90 - 100 in 70% of pts and 70 - 80 in 30%. Combining results for stages 1 and 2, ORR was 35% by independent assessment, median DOR was 8.9 mo (95% CI, 6.01 - 8.94), median OS and PFS were 9.2 mo (95% CI, 7.60 - 11.10) and 5.5 mo (95% CI, 5.29 - 7.16), respectively (Table). Baseline NLR ≤ 5 was associated with a nonsignificant trend toward longer OS vs NLR > 5 (median, 10.0 vs 8.3 mo; HR 0.62; P= 0.148). The most common grade ≥ 3 adverse events included neutropenia (37%), leukopenia (31%), and fatigue (14%). Grade ≥ 3 peripheral neuropathy occurred in 7% of pts. Part 3 was not triggered per study design. Conclusions: nab-P + Gem demonstrated efficacy in Chinese pts with MPC. The OS and ORR were numerically better than those of the phase III MPACT trial (Table). A trend toward longer OS in pts with baseline NLR ≤ 5 vs > 5 confirmed previous findings from the MPACT study. No new safety signals were identified. Clinical trial information: NCT02135822. [Table: see text]