402P Efficacy and safety of sintilimab plus docetaxel in patients with previously treated advanced non-small cell lung cancer (NSCLC)

Abstract

Immuno-checkpoint inhibitors (ICIs) has become standard second line therapy for advanced NSCLC patients (pts). However, early progression remained a major challenge with ICIs monotherapy. The synergetic effect of ICIs plus chemotherapy has been demonstrated in first line setting. Our study aims to explore if the combination of a PD-1 inhibitor with chemotherapy can provide additional clinical benefits in previously treated advanced NSCLC pts. Advanced NSCLC pts who had failed standard platinum doublet without receiving any ICIs before would be enrolled in this single-arm phase II study. EGFR/ALK positive pts must be TKIs failure or intolerable. Eligible pts would receive docetaxel (75mg/m2, day 1) plus sintilimab (200mg, day 3) every 3 weeks for 4-6 cycles followed by sintilimab maintenance until disease progression, unacceptable toxicity, or up to 2 years. The primary end point is progression-free survival (PFS) per RECIST v1.1. Secondary end points included overall response rate (ORR), duration of response (DOR), overall survival, and safety. From 10/2019 to 4/2020, 28 pts were enrolled. Most were male (75%) and adenocarcinoma (85.7%). 21.4% pts had brain metastasis at baseline. Median follow-up was 5.1m (range 2.4-8.1) as of data cut-off (6/17/2020). 42.9% (12/28) pts were still on study treatment. PFS data was immature with only 35.7% (10/28) events. Estimated median PFS was 5.5m (95%CI 3.6-NE). Of the 25 evaluable pts, ORR is 24% (95%CI 9%, 45%), DCR is 92% (95%CI 74%, 99%). Median DOR was not reached (95% 1.28m, NA). Overall, 60.7% (17/28) pts had experienced treatment emergent adverse events (TEAEs), including 17.9% (5/28) grade 3-4 cases. No AEs led to treatment discontinuation or death. The most common TEAEs were leukopenia (50%), neutropenia (28.6%), alopecia (17.9%), lymphopenia (14.3%) and fatigue (14.3%). This first report of a PD-1 inhibitor plus chemotherapy in advanced Chinese NSCLC pts who had failed first-line chemotherapy showed encouraging efficacy and tolerable safety profile. Enrollment is ongoing and more data will be presented.