Inclusion Criteria:

          -  Histologically proven LGSOC (ovarian, peritoneal)

          -  In Part A KRAS mutation, KRAS wt

          -  Progression or recurrence of LGSOC after at least one prior systemic therapy for
             metastatic disease.

          -  Measurable disease according to RECIST 1.1

          -  An Eastern Cooperative Group (ECOG) performance status ≤ 1.

          -  Adequate organ function

          -  Adequate recovery from toxicities related to prior treatments

          -  Agreement to use highly effective method of contraceptive

        Exclusion Criteria:

          -  Systemic anti-cancer therapy within 4 weeks of the first dose of study therapy

          -  Co-existing high-grade ovarian cancer or another histology

          -  History of prior malignancy with recurrence <3 years from the time of enrollment

          -  Major surgery within 4 weeks

          -  Symptomatic brain metastases requiring steroids or other interventions

          -  Known SARS-Cov2 infection (clinical symptoms) ≤28 days prior to first dose of study
             therapy

          -  For subjects with prior MEK exposure, Grade 4 toxicity deemed related to the MEK
             inhibitor

          -  Active skin disorder that has required systemic therapy within the past year

          -  History of rhabdomyolysis

          -  Concurrent ocular disorders

          -  Concurrent heart disease or severe obstructive pulmonary disease

          -  Subjects with the inability to swallow oral medications