Tuvusertib Combined With Niraparib or Lartesertib in Participants With Epithelial Ovarian Cancer (DDRiver EOC 302)

Inclusion Criteria:

• Histologically or cytologically confirmed high grade serous or high gradeendometrioid ovarian, primary peritoneal, and/or fallopian tube cancer that isrecurrent.

• Participants whose tumor carries germline or somatic deleterious or suspecteddeleterious mutations in the genes BRCA1 (Breast Cancer gene 1) and BRCA2 (BreastCancer gene 2), and/or tumors with positive HRD status. The presence of any of thesemutations and/or the homologous recombination deficiency (HRD) status will bedetermined according to routinely used local standard of care tests. Results must beavailable before screening.

• Radiologically confirmed/documented disease progression while on Poly (ADP-ribose)polymerase (PARP) inhibitors therapy in either first or second-line maintenancesetting (only 1 line of PARPi maintenance is allowed with or without bevacizumab).Note: Documentation of disease progression must be within 28 days of last PARPi dosetaken. Surgical salvage intervention and/or focal ablative therapies are allowed, (further disease progression after these interventions must be documented), ANDClinically benefited from PARPi maintenance prior to documented progression, asdefined by at least 6 months of treatment duration with no progressive diseaseobserved, AND either, Progression on first-line maintenance PARPi: Participants areallowed maximum 1 additional line of platinum-based chemotherapy before study entry. (note: treatment-free interval on platinum rechallenge must be >6 months, withdocumented disease progression prior to study entry).

OR Progression on second-line maintenance PARPi: Participants are not allowed any additional systemic anticancer treatments before study entry (that is PARPi is the last treatment before study entry)

• Intolerant to standard of care treatment options or refused standard of caretreatment or the participant's treating physician considers that the lack ofstandard of care treatment is not detrimental for the participant.

• Measurable disease per RECIST v1.1, as assessed by Investigator.

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 and a lifeexpectancy of at least 6 months.

• Other Protocol defined inclusion criteria could apply.

Exclusion Criteria:

• Primary platinum-refractory disease defined as disease progression during primaryplatinum-based chemotherapy or platinum-resistant disease defined as diseaseprogression within 6 months of the platinum administration in either the first orsecond-line setting.

• History of additional malignancy within 3 years before the date of enrollment.

• Known brain metastases, unless clinically stable, that is without evidence ofprogression by imaging for at least 4 weeks prior to the first dose of studyintervention, no evidence of new brain metastases, and on a stable or decreasingdose of ≤ 10 mg of prednisone (or equivalent) or without corticosteroids for atleast 14 days prior to study intervention administration.

• Active and/or uncontrolled infection.

• History of known hypersensitivity to the active substances or to any excipients (e.g. polysorbate 80) of the study interventions.

• Organ transplantation, including allogenic stem cell transplant.

• Patients with history of drug-induced severe cutaneous adverse reaction (SCAR;including but not limited to Stevens-Johnson syndrome/toxic epidermal necrolysis [SJS/TEN], or drug reaction with eosinophilia and systemic symptoms [DRESS]), ordose-limiting immune-mediated reactions related to skin.

• Other Protocol defined exclusion criteria could apply.