A Clinical Trial of Raludotatug Deruxtecan (R-DXd) With or Without Bevacizumab in Participants With Ovarian Cancer Who Have Progressed During Treatment With PARP-inhibitors Treatment on First Line Maintenance (MK-5909-008/ENGOT-ov107/GOG-3142 / REJOICE-Ovarian05)

Participants will receive intravenous (IV) raludotatug deruxtecan (R-DXd) with or without IV bevacizumab for up to 2 years until progressive disease (PD), unacceptable toxicity, or other protocol-specified reason for discontinuation

Biological: R-DXd · Drug: Bevacizumab

Participants receive 6 to 8 cycles of investigator's choice of one of three options of platinum-based chemotherapy with or without IV bevacizumab. Bevacizumab treatment if elected, will continue until PD, unacceptable toxicity, or other protocol specified reason for discontinuation

Drug: Bevacizumab · Drug: Carboplatin · Drug: Paclitaxel · Drug: Gemcitabine · Drug: Pegylated liposomal doxorubicin (PLD)

R-DXd alone or in combination with bevacizumab administered via IV infusion

Bevacizumab 10 or 15 mg/kg administered via IV infusion on day 1 q3w

Carboplatin area under the curve (AUC) 5 mg/mL\*min or AUC 4 mg/mL\*min administered on day 1 q3w for a maximum of 8 cycles

Paclitaxel 175 mg/m\^2 administered via IV infusion on day 1 q3w for a maximum of 8 cycles

Gemcitabine 1000 mg/mL administered via IV infusion on day 1 and day 8 of each 3-week cycle for a maximum of 8 cycles

PLD 30 mg/m\^2 administered via IV infusion on day 1 of each 4-week cycles for a maximum of 8 cycles

Plazo: Up to approximately 3 years

PFS is defined as the time from randomization to the first documented disease progression per Response Criteria in Solid Tumors Version 1.1 (RECIST 1.1) or death due to any cause, whichever occurs first. Disease progression is defined as ≥20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of ≥5 mm. The appearance of one or more new lesions is also considered disease progression. PFS as assessed by blinded independent central review (BICR) will be presented.

Plazo: Up to approximately 4 years

OS is defined as the time from randomization to death due to any cause.

Plazo: Up to approximately 3 years

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.

An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.

Plazo: Up to approximately 3 years

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.

An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.

Plazo: Up to approximately 3 years

ORR is defined as the percentage of participants with Complete Response (CR: disappearance of all target lesions) or Partial Response (PR: at least a 30% decrease in the sum of diameters of target lesions) per Response Evaluation Criteria In Solid Tumors Version 1.1 (RECIST 1.1). The percentage of participants who experience CR or PR as assessed by Blinded Independent Central Review (BICR) will be presented.

Plazo: Up to approximately 3 years

For participants who demonstrate confirmed CR or PR, duration of response is defined as the time from the first documented evidence of CR or PR until disease progression or death due to any cause, whichever occurs first. Per RECIST 1.1, disease progression (DP) is defined as at least a 20% increase in the sum of diameters of target lesions. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions is also considered DP.

Plazo: Up to approximately 4 years

PFS2 is defined as the time from randomization to the documented subsequent objective disease progression after initiation of new anticancer therapy or death due to any cause, whichever occurs first.

Plazo: Up to approximately 3 years

TFST is defined as the time from randomization to initiation of first subsequent anticancer treatment or death due to any cause, whichever occurs first.

Plazo: Baseline and at designated time points up to approximately 3 years

EORTC QLQ-C30 is a questionnaire to assess the overall quality of life of cancer patients. Participant responses to the questions "How would you rate your overall health during the past week?" and "How would you rate your overall quality of life during the past week?" are scored on a 7-point scale (1= Very poor to 7=Excellent). Using linear transformation, raw scores are standardized, so that scores range from 0 to 100. A higher score indicates a better overall health status. The change from baseline in EORTC QLQ-C30 Items 29 and 30 combined score will be presented.

Plazo: Baseline and at designated time points up to approximately 3 years

EORTC QLQ-OV28 is an ovarian cancer-specific module to supplement the EORTC QLQ-C30. Participant responses to the 6 abdominal/GI symptoms scale questions are scored on a 4-point scale (1=not at all, 4=very much). The combined score is computed by averaging the raw scores of the 6 items and then applying a linear transformation to standardize the average score, so that the combined score ranges from 0 to 100. The change from baseline in abdominal and gastrointestinal symptoms (EORTC QLQ-OC28 Items 31-36) score will be presented. A lower score indicates a better outcome.

A Phase 3, Open-Label, Multicenter, Randomized Study of Raludotatug Deruxtecan (MK-5909, R-DXd) With or Without Bevacizumab Versus Standard-of-Care Platinum-Based Doublet Chemotherapy With or Without Bevacizumab in Participants With Advanced Platinum-Sensitive High-Grade Serous or High-Grade Endometrioid Epithelial Ovarian, Primary Peritoneal, or Fallopian Tube Cancer Who Have Progressed During First-Line PARPi Maintenance (ENGOT-ov107 / GOG-3142 / REJOICE-Ovarian05)