Mirdametinib is an orally active, small-molecule MEK1 and MEK2 inhibitor used in targeted oncology and rare-disease pharmaceutical applications. It is a selective, non-ATP-competitive inhibitor of mitogen-activated protein kinase kinase (MEK), a key component of the MAPK signaling pathway.
Mirdametinib is used in pharmaceutical formulations for neurofibromatosis type 1 (NF1) associated plexiform neurofibromas. It is marketed in the United States as GOMEKLI and received FDA approval in 2025.
Mirdametinib is a specialized targeted oncology and rare-disease pharmaceutical API used in the development and manufacture of oral pharmaceutical formulations.
Important API quality attributes may include identity, assay, related substances, water content, residual solvents, elemental impurities, stereochemical purity and solid-state characteristics.
CAS Number: 391210-10-9
Molecular Formula: C₁₆H₁₄F₃IN₂O₄
Molecular Weight: 482.20 g/mol
Chemical Name: (R)-N-(2,3-dihydroxypropoxy)-3,4-difluoro-2-((2-fluoro-4-iodophenyl)amino)benzamide
Development Code: PD-0325901 / PD-0325901-related development code
Drug Class: MEK Inhibitor
Therapeutic Class: Targeted Antineoplastic Agent
Therapeutic Area: Oncology / Rare Diseases
Molecule Type: Synthetic Small Molecule
Mirdametinib selectively inhibits MEK1 and MEK2, which are components of the RAS/RAF/MEK/ERK signaling pathway.
Its pharmacological activity includes:
Mirdametinib binds to MEK at an allosteric site rather than competing directly with ATP, thereby inhibiting MEK activity and downstream ERK phosphorylation.
Mirdametinib API is used in pharmaceutical development for:
Mirdametinib is particularly relevant to NF1-associated plexiform neurofibromas, where dysregulation of the RAS/MAPK pathway contributes to abnormal cell growth.
By inhibiting MEK1 and MEK2, mirdametinib reduces downstream MAPK signaling involved in cellular proliferation and tumor growth.
Mirdametinib is described as a white to tan or pink solid. Its aqueous solubility is 0.25 mg/mL, and the pH of water containing mirdametinib is 7.2 at 25°C. The reported pKa is 7.96.
A controlled Mirdametinib API manufacturing process may involve:
The final manufacturing process should follow the validated process and applicable pharmaceutical quality requirements.
Typical Mirdametinib API testing may include:
Numerical acceptance criteria should be taken from the current validated API specification or CoA rather than using generic pharmaceutical limits.
Store Mirdametinib API in a tightly closed container under controlled pharmaceutical storage conditions, protected from excessive moisture, heat and direct light. Final API storage conditions should follow validated stability data and the applicable approved specification.
Mirdametinib is relevant to research involving:
Mirdametinib is a selective MEK1/MEK2 inhibitor with CAS Number 391210-10-9, molecular formula C₁₆H₁₄F₃IN₂O₄, and molecular weight 482.20 g/mol. It is used as an oral targeted therapy for NF1-associated plexiform neurofibromas and is marketed as GOMEKLI.
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder or crystals |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| pH (1% Solution) | 7.2 in water at 25°C |
| Water Content | NMT 1.0% |