A phase 1b dose optimization study of sovilnesib (an oral KIF18A inhibitor) in subjects with advanced high grade serous ovarian cancer

This is a randomized, phase 1b study to assess the safety, tolerability, pharmacokinetics
(PK), and efficacy of sovilnesib at different dose levels to establish the Recommended
Phase 2 Dose (RP2D) of sovilnesib in subjects with high grade serous ovarian cancer
(HGSOC).

Key Inclusion Criteria:

- All Parts: Age ≥ 18 years, ECOG Performance Status ≤ 1, at least 1 site of
measurable disease evaluable by CT scan or MRI per RECIST 1.1, able to take oral
medication without alteration

- High Grade Serous Ovarian Cancer, Fallopian Tube or Primary Peritoneal Cancer -
histologically or cytologically confirmed; metastatic or unresectable; platinum
resistant (defined as recurrence within 6 months of platinum containing therapy) or
platinum refractory; prior bevacizumab treatment, or ineligible or intolerant to
bevacizumab, or did not receive bevacizumab based on Investigator judgement; if
germline and/or somatic BRCA1/2 mutation, previously treated with PARP-inhibitor or
ineligible or intolerant.

Key Exclusion Criteria:

- MSI-H, dMMR, POLE gene hotspot mutated, or known hypermutator phenotype

- Endometrioid, clear cell, mucinous, sarcomatoid, low-grade/borderline ovarian tumor
or mixed tumors containing any of the above histologies

- Previously received KIF18A inhibitor

- Current CNS metastases or leptomeningeal disease

- Cardiac parameters: MI or stroke ≤ 6 months, unstable angina/PE/DVT/CABG ≤ 6 months,
NYHA Class ≥ II, LVEF < 50%

- Any gastrointestinal condition (e.g. malabsorption syndrome, surgical anastomosis,
short bowel syndrome) that might affect the absorption of oral medications including
the study drug