A Study to Assess Naporafenib (ERAS-254) Administered With Trametinib in Patients With NRAS-mutant Melanoma (SEACRAFT-2)

Key Inclusion Criteria:

1. Willing and able to provide written informed consent

2. Age ≥ 18 years

3. Histologically or cytologically confirmed unresectable or metastatic cutaneous (includes acral) melanoma.

4. Documentation of an NRAS mutation (tumor tissue or blood) prior to first dose ofstudy drug(s) as determined locally with an analytically validated assay in acertified testing laboratory.

5. Archival tumor tissue collected within 5 years prior to enrollment must be confirmedto be available at the time of Screening, which may be submitted before or afterenrollment for exploratory biomarker analysis.

6. Must have received an anti-PD-1/L1 based regimen (monotherapy or combination).Patient must have documented disease progression either while receiving therapy orwithin 12 weeks of last dose of the most recent anti-PD-1/L1 based regimen; thepatient is eligible if they have received other therapies between the most recentanti-PD-1/L1 based regimen and enrollment.

7. ECOG performance status 0, 1 or 2

8. Presence of at least 1 measurable lesion according to RECIST v1.1

9. Able to swallow oral medication.

Key Exclusion Criteria:

1. Patients with uveal or mucosal melanoma

2. Prior therapy with an ERK-, MEK-, RAF-, or RAS-inhibitor

3. Impairment of gastrointestinal (GI) function or GI disease that may significantlyalter the absorption of study drug(s) (e.g., ulcerative diseases, uncontrollednausea, vomiting, diarrhea, malabsorption syndrome, small bowel resection)

4. History or current evidence of retinal vein occlusion (RVO) or current risk factorsfor RVO (e.g., uncontrolled glaucoma or ocular hypertension, history ofhyperviscosity or hypercoagulability syndrome)

5. LVEF <50%

6. Symptomatic CNS metastases that are neurologically unstable. Patients withcontrolled CNS metastases are eligible.

7. Patients receiving treatment with herbal medicine known to cause liver toxicity,which cannot be discontinued 7 days prior to first dose of study drug(s) and for theduration of the study.

8. Are pregnant or breastfeeding or expecting to conceive or father children within theprojected duration of the trial