A Study of ERAS-0015 in Patients With Advanced or Metastatic Solid Tumors

Inclusion Criteria: * Age ≥ 18 years * Willing and able to give written informed consent * Pathological documentation of tumor type and mutation prior to the first dose of study drug(s), for applicable cohorts. * There is no available standard systemic therapy available for the patient's tumor histology and/or molecular biomarker profile; or standard therapy is intolerable, not effective, or not accessible; or patient has refused standard therapy. Does not apply to newly diagnosed Pancreatic Ductal Carcinoma (PDAC) cohort. * Able to swallow oral medication * Have Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 or 1 * Adequate cardiovascular, hematological, liver, and renal function * Willing to comply with all protocol-required visits, assessments, and procedures Exclusion Criteria: * Previous treatment with a RAS inhibitor * Is currently receiving another study therapy or has participated in a study of an investigational agent and received study therapy within 4 weeks of the first dose of ERAS-0015 * Received prior palliative radiation within 14 days of Cycle 1, Day 1 * Have primary central nervous system (CNS) tumors * Prior surgery (e.g., gastric bypass surgery, gastrectomy) or gastrointestinal dysfunction (e.g., Crohn's disease, ulcerative colitis, short gut syndrome) that may affect drug absorption * Have any underlying medical condition, psychiatric condition, or social situation that, in the opinion of the Investigator, would compromise study administration as per protocol or compromise the assessment of AEs * Are pregnant or breastfeeding or expecting to conceive or father children within the projected duration of the trial