INNOVENT BIO's IBI354 has shown good efficacy in treating advanced solid tumors, breast cancer, and late-stage gynecological cancers.

The European Society for Medical Oncology (ESMO) Annual Meeting in 2024 will be held in Barcelona, Spain from September 13th to 17th. Recently, the official website of the ESMO conference has released the abstracts selected for Mini Oral presentations, with two phase 1 studies evaluating the safety and efficacy of INNOVENT BIO's (01801) HER2-targeted antibody-drug conjugate (ADC) IBI354 in advanced solid tumors, breast cancer, and advanced gynecological cancer patients. The reports show that in the treatment of advanced solid tumors and breast cancer, the Disease Control Rate (DCR) can reach 93.3%, while for advanced gynecological tumors, the DCR reaches 92.9%. IBI354 demonstrated good tolerability and efficacy in patients with advanced gynecological cancer. IBI354 is an ADC product containing the anti-HER2 antibody trastuzumab and a topoisomerase I inhibitor. Currently, the product is undergoing phase 1 clinical studies for various HER2-positive solid tumors. In the study evaluating IBI354 in advanced solid tumors and breast cancer, the DCR can reach 93.3%. The global multicenter phase 1 study of IBI354 in patients with advanced solid tumors and breast cancer has been selected for the Mini Oral session at the ESMO conference. The study included patients who had failed standard treatment or were intolerant to it. The dosing of IBI354 ranged from 0.8 to 15mg/kg, administered every 3 weeks or every 2 weeks. Dose expansion selected the dose level of 6mg/kg. The primary endpoint was safety, with secondary endpoints including Objective Response Rate (ORR), DCR, Duration of Response (DOR), and Progression-Free Survival (PFS) based on RECIST v1.1. As of March 22, 2024, a total of 318 patients from China and Australia, who had received 2 prior treatment regimens, were enrolled in the study. The median treatment duration was 14.2 weeks, with 215 patients (67.6%) still receiving treatment. No dose-limiting toxicities were observed at any dose level. Treatment-related adverse events occurred in 257 patients (80.8%), with severe TRAEs occurring in 16.7% of all patients and 16.0% in the 12mg/kg Q3W cohort. Eleven patients (4.1%) experienced serious TRAEs, with one requiring dose reduction and one requiring discontinuation, and no TRAE-related deaths were reported. One patient (0.3%) developed interstitial lung disease (Grade 1). Efficacy data showed that as of April 25, 2024, 44 HER2-positive breast cancer patients who had received at least one tumor assessment had an ORR of 61.4% and a DCR of 88.6%. The ORR and DCR were 57.1% and 85.7% for the 6mg/kg Q3W dose, 53.3% and 86.7% for the 9mg/kg Q3W dose, and 73.3% and 93.3% for the 12mg/kg Q3W dose. Twenty-six patients with low HER2 expression in breast cancer had received at least one tumor assessment and a dose of 12mg/kg Q3W, with an ORR of 53.8% and a DCR of 88.5%. Duration of Response and Progression-Free Survival were still immature. The researchers believe that IBI354 demonstrates good tolerability at doses up to 12mg/kg and shows good efficacy in both HER2-positive and low HER2 expression breast cancer patients. IBI354 treatment for advanced gynecological tumors can achieve a DCR of 92.9%. An ongoing phase 1 study of IBI354 in patients with advanced gynecological cancers was also accepted for the Mini Oral session at the ESMO conference. In this study, patients with HER2 IHC 1+, 2+, or 3+ advanced cervical cancer (CC), endometrial cancer (EC), or platinum-resistant ovarian cancer (OC) who had failed standard treatment or were intolerant to it from China and Australia were treated with IBI354 at doses of 6, 9, or 12mg/kg Q3W. The primary endpoint of the study was safety, with secondary endpoints including ORR, DCR, Duration of Response, and Progression-Free Survival based on RECIST v1.1. As of March 22, 2024, a total of 129 patients were enrolled, including 89 with OC, 26 with CC, and 14 with EC. The median treatment duration was 12.3 weeks. The incidence of TRAEs was 81.4% (105 cases), with a rate of 3% TRAEs of 16.3%. The most common TRAEs (20%) were anemia (34.1%), leukopenia (30.2%), nausea (29.5%), and neutropenia (21.7%). No cases of interstitial lung disease were observed. The rate of severe TRAEs was 7.0%, with no TRAEs leading to treatment interruption or death. As of April 25, 2024, for patients who had received at least one tumor assessment (n=124), the ORR was 39.5% and the DCR was 83.1%. The ORR for OC patients was 41.9%, with a DCR of 81.4%. For the 40 OC patients treated with a 12mg/kg dose, the ORR and DCR were 45.0% and 90.0%, respectively. For the 14 patients with HER2 2/3+ CC and EC, the ORR and DCR were 57.1% and 92.9%, respectively, with one endometrial cancer patient achieving complete remission and seven (four cervical cancer and three endometrial cancer) achieving partial remission. Duration of Response and Progression-Free Survival were still immature. The researchers believe that IBI354 demonstrates good tolerability and shows good efficacy in patients with advanced gynecological cancers.