A Study of ERAS-4001 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)
* 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
* 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-4001
* 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