179O - A phase II, open-label, single-arm study of QL1604 plus paclitaxel-cisplatin/carboplatin as first-line treatment in patients with recurrent or metastatic cervical cancer

Background

Programmed cell death-1 (PD-1) inhibitors have shown efficacy in cervical cancer as monotherapy. QL1604 is a humanized monoclonal antibody against PD-1 and has shown antitumor activity in phase (Ph) I study. Here we report the safety and efficacy results from a Ph II study of QL1604 plus paclitaxel-cisplatin/carboplatin as first-line treatment in patients (pts) with recurrent or metastatic cervical cancer.

Methods

Pts with recurrent or stage IVB cervical cancer not previously treated with systemic chemotherapy were enrolled to receive QL1604 (200 mg)+paclitaxel (175 mg/m²)+cisplatin (70 mg/m²)/carboplatin (AUC 6) at day 1 of each 21-day cycle for up to 6 cycles. Then pts continued to receive QL1604 200 mg Q3W maintenance treatment until disease progression, intolerable toxicity, or other discontinuation events. Primary endpoints were safety endpoints and ORR by investigators per RECIST v1.1 and iRECIST.

Results

46 pts were enrolled (squamous cell carcinoma: 41). 39 (84.8%) pts had recurrent disease and 7 (15.2%) pts had stage IVB disease. 38 (82.6%) pts had ECOG PS of 1. As of data cutoff (22 Apr 2022), 97.8% pts experienced TRAEs and 78.3% pts experienced grade (Gr)≥3 TRAEs. The most common TRAEs were white blood cell count decreased (78.3%), neutrophil count decreased (76.1%), and anemia (71.7%). The most common Gr≥3 TRAEs were neutrophil count decreased (47.8%), anemia (32.6%), and white blood cell count decreased (28.3%). 26.1% pts experienced irAEs. 34.8% pts experienced treatment-related SAEs (TRSAEs). ORR and iORR were 58.7% (27/46) and 60.9% (28/46). 6 pts (13.0%) had CR and 21 pts (45.7%) had PR as best response. DCR and iDCR were 84.8% (39/46) and 89.1% (41/46). The median duration of response was 9.6 months (95% CI: 5.5, NE). The median follow-up time for PFS was 6.23 months (range: 0 to 14 months). The median PFS was 8.1 months (95% CI: 5.7, NE). The 12-month PFS rate was 37%. OS was not reached.

Conclusions

QL1604+paclitaxel+cisplatin/carboplatin showed a manageable safety profile and promising antitumor activity as first-line treatment for pts with recurrent or metastatic cervical cancer.

Clinical trial identification

NCT04864782.

Editorial acknowledgement

Legal entity responsible for the study

Qilu Pharmaceutical Co., Ltd.

Funding

Qilu Pharmaceutical Co., Ltd.

Disclosure

X. Zheng, M. Si, B. Zhang, L. Li, X. Kang: Other, Personal, Full or part-time Employment: Qilu Pharmaceutical. All other authors have declared no conflicts of interest.