Abemaciclib for the Treatment of Recurrent Ovarian or Endometrial Cancer

Inclusion Criteria: * Histologically-confirmed ovarian epithelial (including fallopian tube and primary peritoneal) cancer or endometrial cancer * Molecular tumor board confirms that patient's archival ovarian cancer tumor specimen has been assessed using standard of care genomic profiling and demonstrates CDK4/6 activation features * Molecular tumor board confirms that patient's archival endometrial cancer tumor specimen has been assessed using standard of care genomic profiling and is of endometrioid histology, has positive hormone receptor expression and lack of Cyclin E gene (CCNE) amplification or retinoblastoma susceptibility gene product (RB) loss * At least one prior chemotherapy regimen for the treatment of recurrent ovarian or endometrial cancer * Patients who received chemotherapy must have recovered (Common Terminology Criteria for Adverse Events \[CTCAE\] grade =\< 1) from the acute effects of chemotherapy except for residual alopecia or grade 2 peripheral neuropathy prior to enrollment. A washout period of at least 21 days is required between last chemotherapy dose and study initiation * Patients who received radiotherapy must have completed and fully recovered from the acute effects of radiotherapy. A washout period of at least 14 days is required between end of radiotherapy and study initiation * The patient is able to swallow oral medications * Patient has an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 * Patient must be willing and ab…