A First-in-human Study of PARP1 Selective Inhibitor, IMP1734, in Participants With Advanced Solid Tumors

Key Inclusion Criteria

• Breast cancer; must have received at least one prior chemotherapy inneoadjuvant/adjuvant/metastatic setting, must have received hormonal therapy if HR+,

• HGSOC or high grade endometrioid EOC, fallopian tube or primary peritoneal cancer;must have received at least one prior platinum-based chemotherapy for advanceddisease

• mCRPC with ongoing ADT, must have received NHA and up to 1 prior line of taxanechemotherapy

• Age ≥ 18 years at the time of informed consent

• Eastern Cooperative Oncology Group (ECOG) performance status ≤1

• Adequate organ function

• Life expectancy ≥ 12 weeks

• Should have evaluable disease as defined by RECIST1.1 and/or CA125 or PSA

• Female subjects of childbearing potential and male subjects must agree to use aneffective method of contraception from study entry up to 6 months after the lastdose of IMP1734

• deleterious or suspected deleterious germline or somatic mutations of select HRRgenes

• up to 1 prior line of PARP inhibitor containing treatment

Key Exclusion Criteria:

• Any investigational or approved anti-cancer therapies administered within 28 days/before the first dose of IMP1734

• Have received prior PARP1 selective inhibitors

• Mean resting QTcF > 470 ms or QTcF < 340 ms

• Active or untreated central nervous system (CNS) metastases and/or carcinomatousmeningitis.

• Infections

• An active hepatitis B/C infection

• Any known predisposition to bleeding

• Unable to swallow oral medications OR have malabsorption syndrome or any otheruncontrolled gastrointestinal condition that might impair the bioavailability