First-in-Human Study of ATX-295, an Oral Inhibitor of KIF18A, in Patients With Advanced or Metastatic Solid Tumors, Including Ovarian Cancer

The goal of this study is to identify a safe and tolerated dose of the orally administered KIF18A inhibitor ATX-295. In addition, this study will evaluate the pharmacokinetics, pharmacodynamics and preliminary antitumor activity of ATX-295 in patients with advanced solid tumors and ovarian cancer.

Key Inclusion Criteria: * Patients with histologically confirmed solid tumors who have locally recurrent or metastatic disease, including HGSOC * Refractory to or relapsed after all standard therapies with proven clinical benefit, unless as deemed by the Investigator, the subject is not a candidate for standard treatment, there is no standard treatment, or the subject refuses standard treatment after expressing an understanding of all available therapies with proven clinical benefit * For the expansion cohorts, participants must have histological confirmation of HGSOC and be determined to be platinum-resistant, platinum-refractory, or platinum-intolerant * There is no limit to the number of prior treatment regimens * Have measurable or evaluable disease * Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1 Key Exclusion Criteria: * Clinically unstable central nervous system (CNS) tumors or brain metastasis * Any other concurrent anti-cancer treatment, except for hormonal blockade * Has undergone a major surgery within 3 weeks of starting study treatment * Medical issue that limits oral ingestion or impairment of gastrointestinal function that is expected to significantly reduce the absorption of ATX-295, however participants with a functioning distal ileostomy or colostomy may be permitted on trial * Clinically significant (ie, active) or uncontrolled cardiovascular disease * Need to use proton pump inhibitors on study or H2-receptor antagonists for the dose escalation portion of the study. * Unable to transition off strong or moderate CYP3A4 inhibitors or strong inducers * Pregnancy or intent to breastfeed or conceive a child within the projected duration of treatment Other inclusion and exclusion criteria as defined in the study protocol