Authors: Nong Xu, Chenyu Mao, Jiong Qian, Yulong Zheng, Haiping Jiang, Yuan Gao, Cheng Xiao, Anwen Xiong, Wei Li, Yayi He, Shengxiang Ren, Lei Wang, Jia Yu, Jun Zhu, Ying Liu, Caicun Zhou
Published: 2022-06-06
DOI: 10.1200/jco.2022.40.16_suppl.2650
Source: Full article
2650 Background: Lymphocyte-activation gene 3 (LAG-3) is an immune checkpoint receptor protein that functions to control T cell response, activation and growth. Dual inhibition of PD-1 and LAG-3 may improve anti-tumor effect synergistically. A phase Ia/Ib dose-escalation study evaluated IBI110 ± sintilimab in patient with advanced solid tumors; initial efficacy and safety data were previously presented (C Zhou et al. ASCO 2021; NCT04085185). Here, we reported the updated results. Methods: Eligible patients were ECOG PS 0-1 and had locally advanced, recurrent or metastatic solid tumors for whom standard therapy had failed. Patients received escalating doses of IBI110 (0.01/0.1/0.3/1/3/10/20mg/kg) IV Q3W in phase Ia and escalating doses of IBI110 (0.3/0.7/1.5/3/5/8/10 mg/kg) in combination with sintilimab 200 mg IV Q3W in phase Ib. Crossover from monotherapy to combination therapy was allowed at progression. The primary objectives were safety, tolerability, and anti-tumor activity of IBI110 alone or IBI110+sintilimab (per RECIST v1.1). Results: Phase Ia: 28 patients (median age of 60.5 years [range 35-72], ECOG PS of 0 [n = 14] and 1 [n = 14]) were enrolled. Dose escalation was completed and no dose-limiting toxicity (DLT) was observed in all dose cohorts. The safety profile was generally consistent with the initial. By investigator-assessment, best response was 1 confirmed partial response (PR) and 6 stable diseases (SD) with monotherapy. After crossing to combination therapy at progression, 8 patients who failed prior anti-PD-(L)1 mAb therapy achieved SD. Phase Ib: Overall, 45 patients (median age: 60.0 yr [range 33-74]; ECOG PS: 0 [n = 14], 1 [n = 31]) were enrolled in all dose levels. Dose escalation was completed and no DLT was observed. The most common treatment-related adverse events (TRAEs) were aspartate aminotransferase increased (28.9%), anaemia (24.4%), and alanine aminotransferase increased (22.2%). TRAEs ≥ grade 3 occurred in 10 (22.2%) patients. Immune-related AE (irAE) incidence was 31.1%, and the most common irAE was hypothyroidism (15.6%). In 43 patients who had undergone at least 1 post-baseline tumor assessment, the investigator-assessed best response included 6 PRs (1 endometrial cancer, 4 NSCLC, and 1 SCLC patients) and 23 SDs. Three patients showed a progression-free survival > 1 year and continued treatment. Conclusions: IBI110 alone or plus sintilimab demonstrated acceptable safety profile and promising antitumor activity in patients with advanced solid tumors. Clinical trial information: NCT04085185.