Mirdametinib Monotherapy in Adults With Neurofibromatosis 1 (NF1) and Cutaneous Neurofibromas (cNF).

This study is designed to assess Mirdametinib safety and efficacy in two phases: phase 1 tests the safety of up to four dose regimens of Mirdametinib, administered continuously or intermittently (3 weeks on/1 week off) to identify up to two recommended phase 2 doses. Phase 2a of the study will test the safety and efficacy of the recommended phase 2 dose(s) in adults with NF1 and cNF. The following dosing strategy will be assessed in participants ≥ 18 years old with NF1 and a minimum of 12 measurable cNF who desire systemic treatment of their cNF due to disfigurement, pain or itching. Each treatment cycle in this study is 28 days.treatment cycle in this study is 28 days.