764P - Tislelizumab (Anti-PD-1) combined with definitive chemoradiotherapy in recurrent and/or metastatic cervical cancer (PILOT-2020-511): A single-arm, phase II trial

Background

Tislelizumab is an investigational, humanized, IgG4 monoclonal antibody with high affinity and binding specificity for programmed cell death-1 (PD-1) emerging as promising investigational agents for the treatment of advanced cervical cancer. This phase II trial evaluated the combination of Tislelizumab plus definitive chemoradiotherapy in patients with recurrent and/or metastatic cervical cancer who relapsed after prior platinum-based therapy.

Methods

PILOT-2020-511 was a single-arm, phase 2 trial done at Fudan University Shanghai Cancer Center (Shanghai, China). Patients aged 18-70 years with recurrent and/or metastatic cervical cancer, with an ECOG performance status of 0-2, and adequate organ and bone marrow function were eligible for inclusion. Patients received concurrent radiotherapy (58-60 Gy in 28 fractions), chemotherapy (4-6 cycles of intravenous paclitaxel [135 mg/m2] and carboplatin [AUC=5]), and tislelizumab (200 mg intravenously every 3 weeks for up to 1 year, or until disease progression or unacceptable toxicity). The primary endpoint was the complete response rate at 3 months after radiotherapy by investigator assessment. Secondary endpoints were overall survival, progression-free survival, duration of response, quality of life (not reported here), and safety. The trial is registered with Chictr.org.cn, ChiCTR2000034748 and follow-up is ongoing.

Results

Between September 1, 2020, and December 25, 2022, 41 patients were enrolled. The median age was 58 years (IQR 52-67), 30 (73.2%) of 42 patients had lymphatic metastasis, and 11 (26.8%) patients were organic metastasis. 40 (97.6%) of 41 patients completed the planned chemoradiotherapy and 32 (78%) of 41 had a complete response. The 1-year overall survival was 66.8% and 1-year progression-free survival was 61.8%. The most common grade 3 or worse adverse event was lymphopenia. The most common immune-related adverse event was thyroid dysfunction.

Conclusions

Combining Tislelizumab with definitive chemoradiotherapy provided encouraging activity and acceptable toxicity in patients with recurrent and/or metastatic cervical cancer, and this regimen warrants further investigation.

Clinical trial identification

ChiCTR2000034748.

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.