A Study to Assess the Efficacy and Safety of FORE8394 in Participants With Cancer Harboring BRAF Alterations

Required: BRAF fusion

Documentation of BRAF gene fusion in tumor and/or blood detected by an analytically validated test by DNA sequencing or RNA (transcriptome) sequencing.

Required: BRAF V600E

Documented BRAF V600E mutation in tumor and/or liquid biopsy detected by an analytically validated test

Excluded: RAS activating mutation

Malignancy with co-occurring activating RAS mutation(s) at any time

Excluded: NF1 mutation

Known or suspected neurofibromatosis-1 (NF-1) and/or RAS related gene alterations

Must have received: standard therapy — all available

Received all available standard therapy, is intolerant to available therapies, or the investigator has determined that treatment with standard therapy is not appropriate.

Must have received: radiotherapy and/or first-line chemotherapy or concurrent chemoradiation therapy — glioma

Had prior treatment with radiotherapy and/or first-line chemotherapy or concurrent chemoradiation therapy OR...not considered standard of care may remain eligible

Cannot have received: RAF/BRAF inhibitor active for Class 2 BRAF alterations

Prior treatment with RAF/BRAF inhibitors active for Class 2 BRAF alterations for advanced unresectable or metastatic disease.

Cannot have received: MEK inhibitor

Prior treatment with a MEK inhibitor.

Cannot have received: BRAF inhibitor

Prior treatment with BRAF, ERK, and/or MEK inhibitor(s).

Cannot have received: ERK inhibitor

Prior treatment with BRAF, ERK, and/or MEK inhibitor(s).