A Two-Part Phase 3 Study of LY4170156 in Participants With Platinum-Resistant (Part A) and Platinum-Sensitive (Part B) Ovarian Cancer

Open to people ages 18 years and up

Part A and B:

• Have histologically confirmed high-grade serous ovarian, primary peritoneal, or fallopian tube cancer.
• Have confirmed availability of tumor tissue block or slides
• Have radiographic progression on or after most recent line of systemic anticancer therapy
• Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.
• Have measurable disease per RECIST v1.1

Part A:

• Have platinum-resistant disease, defined as radiographic progression less than or equal to (≤)6 months of the last administration of platinum therapy.
• Have previously received greater than or equal to (≥)1 but ≤3 prior lines of systemic cytotoxic therapy. Up to 4 lines of prior therapy is allowed if one of those lines is mirvetuximab soravtansine.
• Have received prior bevacizumab treatment, unless documented contraindication or intolerance.
• Have received treatment with a poly(ADP-ribose) polymerase inhibitor (PARPi) if known to have a somatic or germline breast cancer gene (BRCA) mutation, if clinically indicated, unless documented contraindication or intolerance.

Part B:

• Have relapsed after first-line platinum-based chemotherapy and have platinum-sensitive disease defined as radiographic progression greater than (>)6 months of their last administration of platinum therapy
• Have previously received ≥1 but ≤2 prior lines of systemic cytotoxic chemotherapy
• Have previously received a PARPi, per local product label, with progression on, or within 6 months of completion of PARPi treatment.

Part A and B:

• Have received prior antibody-drug conjugate (ADC) with a topoisomerase inhibitor payload.

Part A:

• Have primary platinum-refractory disease, defined as disease that progressed ≤3 months since the last dose of first-line platinum-containing chemotherapy.

Part B:

• Have clinically significant proteinuria