1632P Analysis of penpulimab plus anlotinib in pleural mesothelioma or thymic carcinoma patients who have received at least one line of chemotherapy

Abstract

Pleural mesothelioma and thymic carcinoma have low morbidity and few treatment options available. Penpulimab is an IgG1 PD-1 antibody, which features point mutations in the antibody Fc region to eliminate all Fc gamma receptor binding and associated effector function. Anlotinib is a multi-targeted tyrosine kinase inhibitor selective for VEGF receptors 1/2/3, FGF receptors 1-4, PDGF receptors α and β, and c-kit，Preclinical research has confirmed that penpulimab and anlotinib can significantly reduce the proportion of TIM3+PD1+CD8+ T cells，improving anti-tumor efficacy. This study aimed to evaluate the efficacy and safety of anlotinib in combination with penpulimab in patients with pleural mesothelioma or thymic carcinoma who have received at least one line of chemotherapy. This study is a single-arm phase II study. Eligible patients had recurrent/metastatic pleural mesothelioma and thymic carcinoma who were inoperable or intolerant to radical radiotherapy and had failed at least first-line chemotherapy, were over 18 years old, with ECOG PS of 0-1. The primary endpoint was ORR, and secondary endpoints were DCR, PFS, DOR, OS and safety. Patients received anlotinib (12mg QD from day 1 to 14 of a 21-day cycle) plus penpulimab (200mg Q3W) until disease progression or intolerance. Between Nov 13, 2020, and May 12,2021, 12 patients were enrolled and treated, including 5 cases of thymic carcinoma and 7 cases of pleural mesothelioma. The data cutoff date was on Apr 19, 2022. There were 10 males and 2 females. All patients had ECOG PS of 1. Four patients received only one prior line of chemotherapy. 11 patients were available for tumor assessment, ORR was 18.2%, and DCR was 81.8%. The data on PFS and OS were not mature. The common TEAE were hypoalbuminemia (75%), hypertension (75%), anemia (75%), and hypertriglyceridemia(62.5%). The incidence of grade 3 or higher treatment-related AEs was 62.5%, and there was one immune-related AE of grade 3 or higher which was hypocalcemia. Penpulimab plus annlotinib demonstrated preliminary antitumor efficacy and acceptable toxicity in pleural mesothelioma or thymic carcinoma patients who have received at least one line of chemotherapy.