A Phase 1 First-in-Human, Open-Label, Multicenter Study of OP-3136 in Adult Participants With Advanced or Metastatic Solid Tumors
This is a first-in-human, open-label, multicenter phase 1 study to evaluate safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary efficacy of OP-3136, a lysine acetyltransferases 6A and 6B (KAT6A/B) inhibitor, as monotherapy and in combination with other anticancer agents in participants with advanced solid tumors. This study consists of 2 parts: a dose escalation part (Part 1) and dose expansion part (Part 2).
• Participants with advanced or metastatic ER+HER2- breast cancer, mCRPC, or NSCLC (Part 1) or advanced or metastatic ER+HER2- BC or mCRPC (Part 2).
• Part 1A (Dose escalation for OP-3136 monotherapy): Participants must have a tumor that is unresectable or metastatic and for which life prolonging measures do not exist or available therapies are intolerable or no longer effective.
• Part 1B (Dose escalation for OP-3136 in combination with fulvestrant): Participants with advanced or metastatic ER+ HER2- breast cancer that have progressed on or after at least 1 prior line of treatment that included endocrine therapy and CDK 4/6 inhibitor in advanced or metastatic setting and must have received no more than 2 prior lines of endocrine therapy (one of which must be in combination with CDK4/6 inhibitor) and no more than 1 prior line of chemotherapy or an antibody-drug conjugate in the advanced or metastatic setting.
• Part 1C (Dose escalation for OP-3136 in combination with palazestrant): Participants with advanced or metastatic ER+ HER2- breast cancer that have progressed on or after at least 1 prior line of treatment that included endocrine therapy and CDK 4/6 inhibitor in advanced or metastatic setting and must have received no more than 2 prior lines of endocrine therapy (one of which must be in combination with CDK4/6 inhibitor) and no more than 1 prior line of chemotherapy or an antibody-drug conjugate in the advanced or metastatic setting.
• Part 2A (Dose Expansion in ER+ HER2- mBC for OP-3136 monotherapy): Participants must have received up to 3 prior lines of endocrine therapy (one of which must be in combination with CDK4/6 inhibitor) and up to 1 prior line of chemotherapy or an antibody-drug conjugate.
• Part 2A (Dose Expansion in mCRPC for OP-3136 monotherapy): Participants must have received up to 4 lines of prior systemic therapy for prostate cancer. Prior therapy must include treatment with an androgen receptor pathway inhibitor(s).
• Part 2B (Dose Expansion in ER+ HER2- mBC for OP-3136 in combination with fulvestrant OR Dose Expansion in ER+ HER2- mBC for OP-3136 in combination with palazestrant): Participants must have progressed on or after at least 1 prior line of treatment that included endocrine therapy and CDK 4/6 inhibitor in advanced or metastatic setting. Participants must have received no more than 2 prior lines of endocrine therapy in the advanced or metastatic setting and no more than 1 prior line of chemotherapy or an antibody-drug conjugate in the advanced or metastatic setting.