Summit Therapeutics Inc. announced promising data for its novel, potential first-in-class investigational bispecific antibody, Ivonescimab, that is being presented at the 2024 European Lung Cancer Congress (ELCC 2024) in Prague, Czech Republic. Two posters featuring updated ivonescimab data will be displayed from 12:00 to 12:45pm Central European Time. The posters will also be made available on website after the presentation period.

The first poster, ?Intracranial Activity of Ivonescimab Alone or in Combination with Platinum Doublet Chemotherapy in Patients with Advanced Non-Small Cell Lung Cancer (NSCLC) and Brain Metastases? includes data from patients with asymptomatic brain metastases at baseline. These patients were enrolled in either AK112-202 (NCT04900363), in which ivonescimab is delivered as monotherapy, or AK112-201 (NCT04736823), in which ivonescimab is delivered in combination with platinum doublet chemotherapy, both of which are Phase II clinical trials for patients with advanced or metastatic NSCLC.

This analysis consisted of the 35 patients with advanced or metastatic NSCLC who had asymptomatic brain metastases at baseline; 28 patients were treated with ivonescimab plus chemotherapy in AK112-201, and seven patients were treated with monotherapy ivonescimab in AK112-202. Notably, median intracranial progression-free survival was 19.3 months across all patients analyzed. Patients across both cohorts experienced an intracranial response rate of 34%, and eight patients (23%) experienced a complete response by RANO criteria.

All patients who did not achieve a response demonstrated stable disease or non-progression; no patients experienced intracranial disease progression at the time of the initial follow-up scan. No cases of intracranial bleeding complications were observed in these patients. The second poster titled, ?Phase 2 Results of Ivonescimab a Novel PD-1/VEGF Bispecific in Combination with Chemotherapy for First Line Treatment of Patients with Advanced /Metastatic Non-Small Cell Lung Cancer?

includes updated data from the Phase II trial AK112-201 centered around the cohort of patients in which ivonescimab is combined with chemotherapy for first-line treatment of squamous and non-squamous advanced or metastatic NSCLC in patients without actionable genomic alterations (e.g., positive for endothelial growth factor receptor (EGFR) mutations or anaplastic lymphoma kinase (ALK)). Summarized updates in NSCLC patients with EGFR mutations after a tyrosine kinase inhibitor (TKI) and NSCLC patients who have received prior PD-(L)1 plus doublet chemotherapy treatment are included as well. Of significance, first-line advanced or metastatic squamous NSCLC patients experienced a median PFS of 11.1 months (95% CI: 9.5 ?

16.3 months). In addition, first-line patients with advanced or metastatic non-squamous tumors experienced a median PFS of 13.3 months (95% CI: 8.3 ? 16.4 months).

Median overall survival was not reached in either subset of patients after a median follow-up time of 22.1 months. The frequency of treatment-emergent adverse events (TEAEs) leading to the discontinuation of ivonescimab was 11.1% and 2.8%, respectively, in patients with squamous and non-squamous tumors. The most frequent TEAEs were anemia and decreased neutrophil counts in squamous patients and anemia and constipation in non-squamous patients.

The posters will be presented by, amongst others, Dr. Li Zhang, Sun Yat-Sen University Cancer Center, and Dr. West, with data generated and analyzed by collaboration and licensing partner, Akeso Inc. (HKEX Code: 9926.HK) with contribution by Summit staff. Summit continues its clinical development of ivonescimab in order to establish its efficacy and safety in two NSCLC indications: · HARMONi Phase III trial: ivonescimab combined with chemotherapy in patients with EGFR-mutated, locally advanced or metastatic non-squamous NSCLC who have progressed after treatment with a third-generation EGFR TKI (NCT05184712) · HARMONi-3 Phase III trial: ivonescimab combined with chemotherapy in first-line metastatic squamous NSCLC patients (NCT05899608) Poster Title: Phase 2 Results of Ivonescimab a Novel PD-1/VEGF Bispecific in Combination with Chemotherapy for First Line Treatment of Patients with Advanced /Metastatic Squamous Non-Small Cell Lung Cancer ELCC Presentation No.: 68P Session Date & Time: March 22, 2024, 12:00 to 12:45pm CET Poster Title: Intracranial Activity of Ivonescimab Alone or in Combination with Platinum Doublet Chemotherapy in Patients with Advanced Non-Small Cell Lung Cancer and Brain Metastases ELCC Presentation No.: 174P Session Date & Time: March 22, 2024, 12:00 to 12:45pm CET.