743MO - Efficacy and safety of QL1706 plus paclitaxel and cisplatin/carboplatin +/- bevacizumab (Bev) as 1L treatment in recurrent or metastatic cervical cancer (r/mCC): A single-arm, multicenter phase II study

Background

Pembrolizumab plus chemotherapy +/- Bev has been approved as the 1L treatment for r/mCC patients (pts) with PD-L1 CPS ≥1. QL1706, a bifunctional Mabpair product of anti-PD-1 and anti-CTLA-4 antibodies, has shown good safety and promising efficacy in previously treated r/mCC pts in a phase Ib study. Here we report the latest efficacy and safety results from a Ph 2 study of QL1706 plus paclitaxel and cisplatin/carboplatin +/- Bev as 1L treatment of r/mCC.

Methods

In this open-label, single arm, non-randomized, phase II study, eligible pts were pathologically confirmed r/mCC and had no prior systemic treatment. Pts were treated with QL1706 (5 mg/kg, IV, D1) plus paclitaxel (175 mg/m² or 135 mg/m², D1) and cisplatin (50 mg/m², D1/D2)/carboplatin (AUC = 5, D1) (cohort 1) or with Bev (15 mg/kg, D1/D2) (cohort 2) once every 3 weeks for 6 cycles. Thereafter, treatment maintained with QL1706 +/- Bev, until disease progression, intolerable toxicity, or other discontinuation events. The primary and secondary endpoints were safety and efficacy, respectively.

Results

A total of 60 pts were enrolled. As of data cutoff (Apr 24, 2023), the median follow-up time was 14.0 months. Overall 58 pts had ≥1 post baseline tumor assessment and analyzed for efficacy. The ORR was 81% (95% CI, 68.6–90.1) (8 CRs and 39 PRs). The DCR was 98.3% (95% CI, 90.8–100.0). The mPFS was 14.3 months (95% CI, 9.2-NE). The mPFS was numerically longer in cohort 2 vs cohort 1 (16.4 vs 12.5 months). The mOS was not reached. TRAEs occurred in 60 (100%) pts. The most common TRAEs (≥30% in total population) were WBC count decreased (73.3%), neutrophil count decreased (58.3%), anemia (43.3%), platelet count decreased (38.3%), and alopecia (33.3%), Grade ≥3 TRAEs occurred in 43 (71.7%) pts. Treatment-related SAEs occurred in 20 (33.3%) pts. TRAEs leading to treatment discontinuation occurred in 16 (26.7%) pts. irAEs occurred in 36 (60%) pts (Grade ≥3, 13.3%).

Conclusions

QL1706 plus platinum-based chemotherapy +/- Bev was well tolerated and showed promising antitumor activity as 1L treatment of r/mCC. Ph 3 study of QL1706 plus platinum-based chemotherapy +/- Bev as 1L treatment of r/mCC is ongoing.

Clinical trial identification

NCT05179317.

Editorial acknowledgement

Legal entity responsible for the study

Qilu Pharmaceutical Co., Ltd.

Funding

Qilu Pharmaceutical Co., Ltd.

Disclosure

X. Zhang, S. Xue, X. Kang: Other, Personal, Full or part-time Employment: Qilu Pharmaceutical. All other authors have declared no conflicts of interest.