ATR Inhibitor Elimusertib (BAY1895344) Plus Niraparib Phase 1b Study in Advanced Solid Tumors and Ovarian Cancer

Inclusion Criteria

• •Participant must be ≥ 18 years of age, at the time of signing the informed consent.
• •Participants must have histologically confirmed diagnosis of the following indications as described below:
• •* Dose escalation (Part A): recurrent advanced solid tumors, excluding prostate cancer, who experienced disease progression after treatment with standard of care therapy for metastatic disease.
• •* Dose expansion (Part B): recurrent EOC, fallopian tube or primary peritoneal cancer
• •* Sub-population 1: participants PARPi naïve and with a platinum-resistant/refractory disease (recurrence with a PFI \< 6 months from last platinum-based regimen). Participants may not have had more than 3 prior therapies since the development of platinum resistance.
• •* Sub-population 2: participants with disease progression on PARPi (including niraparib), administered as maintenance as well active line of therapy. Participants must have not received further line of therapy after disease progression on PARPi.
• •Participants in dose escalation (Part A) of the study will need to have tumor-associated DDR deficiency and/or CCNE1 gene amplification.
• •\-- A homozygous deletion and/or a deleterious mutation in a gene reported to be involved in DNA repair and/or sensitive to ATRi's and/or PARPi's.
• •Participants in dose expansion (Part B) of the study will need to have tumor associated DDR deficiency (Sub-population 1). Participants in Part B (Sub-population 2) are not enrolled based on the presence or absence of a particular biomarker.
• •Participants must have disease progression and measurable disease, as defined by RECIST 1.1.
• •Available archival tumor tissue ≤ 12 months old, otherwise a fresh baseline tumor biopsy should be obtained.
• •ECOG PS of 0 to 1
• •Life expectancy of at least 12 weeks
• •Adequate bone marrow function as assessed by the following laboratory tests to be conducted within 7 (±2) days before the first dose of study intervention:
• •* Hemoglobin (Hb) ≥ 10 g/dL
• •* Platelet count ≥ 150 x 10\^9/L
• •* Absolute neutrophil count (ANC) ≥ 1.5 x 10\^9/L
• •Participants must have adequate organ function.
• •Participants must have adequate coagulation.
• •Adequate cardiac function per institutional normal measured by echocardiography (recommended) or cardiac MRI per institutional guidelines.
• •A female participant is eligible to participate if she is not pregnant (confirmed by a negative serum pregnancy test within 7 (±2) days of first study intervention), not breastfeeding, or is not a woman of childbearing potential (WOCBP). WOCBP must agree to use highly effective contraception during the intervention period and for at least 6 months (180 days) after the last dose of study intervention.