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

Inclusion Criteria:

Part A and B:

• Have histologically confirmed high-grade serous or high-grade endometrioid 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 anticancertherapy

• 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 orequal to (≤)6 months of the last administration of platinum therapy.

• Have previously received greater than or equal to (≥)1 but ≤3 prior lines ofsystemic cytotoxic therapy. Up to 4 lines of prior therapy is allowed if one ofthose lines is mirvetuximab soravtansine.

• Have received prior bevacizumab treatment, unless documented contraindication orintolerance.

• Have received treatment with a poly(ADP-ribose) polymerase inhibitor (PARPi) ifknown to have a somatic or germline breast cancer gene (BRCA) mutation, ifclinically indicated, unless documented contraindication or intolerance.

Part B:

• Have relapsed after first-line platinum-based chemotherapy and haveplatinum-sensitive disease defined as radiographic progression greater than (>)6months 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, orwithin 6 months of completion of PARPi treatment.

Exclusion Criteria:

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