16P Camrelizumab monotherapy or plus apatinib for PD-L1-positive advanced pulmonary sarcomatoid carcinoma: A single-arm, open-label, multicenter, phase II study

As a rare and highly aggressive malignancy, pulmonary sarcomatoid carcinoma (PSC) is insensitive to chemotherapy or radiotherapy and no optimal treatment has been established yet. Because of the high expression of programmed death-ligand 1 (PD-L1), immune checkpoint inhibitors (ICIs) were documented to possess encouraging efficacy in PSC patients (pts). Here we evaluated camrelizumab (Camre) in treating PD-1-positive PSC. Apatinib (Apa) may be used simultaneously with Camre based on the PD-L1 level, as the combination of Camre and Apa exhibited treatment potential in lung cancer in previous study. In this single-arm, open-label, multicenter, phase II study, pts with an age of 18-80 years old, ECOG PS 0-2, PD-L1 positive, histologically or cytologically confirmed stage IIIB-IV PSC regardless of prior therapy lines were enrolled to receive Camre (200 mg, IV, Q3W) plus Apa (250mg, QD) for PD-L1 TPS 1-49%, or Camre monotherapy (200 mg IV Q3W) for PD-L1 TPS≥50%. The primary endpoint was ORR according to RECIST v1.1. From Sep 2020 to Nov 2021, 16 pts (Camre plus Apa, n=3; Camre monotherapy, n=13) were enrolled. Until the final follow-up (Nov 30, 2020), 14 pts received at least one efficacy evaluation. In Camre plus Apa group, ORR was 66.7% (2/3), DCR was 66.7% (2/3), median DoR was 2.53 [95% CI 1.4-3.1] months. In Camre monotherapy group, ORR was 54.5% (6/11), DCR was 90.9% (10/11), median DOR was 3.19 [95% CI 1.1-6.9] months. Median PFS and OS data were not mature. Grade 3 or 4 adverse events were AST/ALT increased [1 (6.25%)], hypophysitis [1 (6.25%)], with no unexpected adverse effects. Adverse events that led to the discontinuation of any agent occurred in 1.9% (3/16) of the pts. No treatment-related deaths were reported. Camre monotherapy or plus Apa showed promising antitumour activity with manageable toxicity profile for PD-L1-positive PSC pts. This encourages the clinical practice with ICIs in PSC.