Abstract 3335: ORIC-114, an orally bioavailable, irreversible kinase inhibitor, has superior brain penetration and antitumor activity in subcutaneous and intracranial NSCLC models

Abstract

Abstract Exon 20 genomic insertions of both epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) are oncogenic drivers and are most commonly found in non-small cell lung cancer (NSCLC). NSCLC patients with exon 20 insertions have a worse prognosis compared to those with other activating EGFR mutations. Moreover, approximately one-third of patients with exon 20 insertion mutations develop central nervous system (CNS) metastases over the course of their disease. Unfortunately, current therapeutics lack sufficient brain exposure for treating this patient population. ORIC-114 is a brain penetrant, orally bioavailable, irreversible small molecule inhibitor designed to target exon 20 insertions in EGFR and HER2. Notably, ORIC-114 is highly selective for the EGFR family of receptors, with excellent kinome selectivity compared to other reported exon 20 inhibitors, reducing the risk of off-target kinase liabilities. The superior brain penetration and free unbound exposure of ORIC-114 in preclinical studies also differentiates it from comparator EGFR and HER2 exon 20 targeted agents. To further characterize ORIC-114, in vivo studies were undertaken to assess activity in both subcutaneous and intracranial NSCLC tumor patient-derived xenograft (PDX) models. Consistent with in vitro potency and selectivity, once daily oral administration of 3 mg/kg ORIC-114 induced robust tumor regressions with greater than 100% tumor growth inhibition in the absence of significant body weight loss in an EGFR exon 20 insertion H773_V774insNPH NSCLC PDX model. In this subcutaneous model, ORIC-114 was superior to CLN-081 in efficacy and tolerability, and superior to BDTX-189 in efficacy. To investigate whether the brain-penetrant attributes of ORIC-114 translated into antitumor activity in the CNS, we utilized an intracranial PC-9 luciferase-labeled EGFR del 19 mutant cell line model. Once daily oral administration of ORIC-114 significantly regressed established intracranial NSCLC tumors and demonstrated greater efficacy than TAK-788, commensurate with the superior brain exposure of ORIC-114. We further explored dosing regimens in this intracranial model and found that ORIC-114 demonstrated equivalent regressions at 1.5 mg/kg twice daily and 3 mg/kg once daily, and strong efficacy with 1.5 mg/kg once daily dosing. Taken together, these data confirm ORIC-114 as a potent, selective, irreversible, brain penetrant exon 20 inhibitor, and a promising therapeutic candidate, including for patients with CNS metastases. Based upon these data, ORIC-114 is entering a Phase 1/1b clinical trial in genetically defined cancers. Citation Format: Jason E. Long, Soochan Kim, Ha Yeong Kim, Dong Guk Shin, Dong Hyun Park, Robert Warne, Akash Das, Ganapati Hegde, Padmini Narayanan, Lidia Sambucetti, Brenda Chan, Xi Chen, Jae H. Chang, Paul Gibbons, Jessica Sun, Matthew Panuwat, Lori S. Friedman, Melissa R. Junttila. ORIC-114, an orally bioavailable, irreversible kinase inhibitor, has superior brain penetration and antitumor activity in subcutaneous and intracranial NSCLC models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3335.