A Study of INCB123667 in Participants With Platinum-Resistant Ovarian Cancer With Cyclin E1 Overexpression

Inclusion Criteria:

• Histological diagnosis of a high-grade serous epithelial ovarian, fallopian tube, orprimary peritoneal cancer.

• Have platinum-resistant disease:

• Participants who have only had 1 line of platinum-based therapy must havereceived at least 4 cycles of a platinum-containing regimen.

• Participants who have received 2 to 4 lines of platinum-based therapy must haveprogressed on or within 6 months after the last dose of platinum.

• Willingness to undergo a pretreatment biopsy. Note: Tissue from a fresh pretreatmentbiopsy is preferred, however an archival sample is acceptable as long as the sampleis no older than 5 years.

• Received at least 1 and no more than 4 prior lines of systemic therapy following theinitial diagnosis, after which single-agent therapy is considered an appropriatenext therapeutic option.

• Must have received bevacizumab unless there was a contraindication for its use.

• If the tumor tests positive for FRα, participants must have received mirvetuximabsoravtansine unless there is an exception for its use on medical grounds.

Exclusion Criteria:

• Have endometrioid, clear cell, mucinous, or sarcomatous histology, mixed tumorscontaining any of these histologies, or low-grade/borderline ovarian cancer.

• Have primary platinum-refractory disease: either did not respond (CR or PR) tofirst-line platinum-containing therapy or progressed on or within 3 months after thelast dose of the first line platinum-containing therapy.

• The tumor tests positive for FRα but the participant has not received mirvetuximabsoravtansine for any reason other than medical contraindication.

• Clinically significant or uncontrolled cardiac disease within 6 months before thefirst dose of study drug.

• Known active CNS metastases and/or carcinomatous meningitis.

• Known additional malignancy that is progressing or requires active treatment.

Other protocol-defined Inclusion/Exclusion Criteria may apply.