Understanding Neurofibromas and Treatment Variation
Neurofibromatosis type 1 (NF1) is a complex genetic disorder characterized by the growth of tumors along nerves [1.6.5]. These tumors, called neurofibromas, can manifest in different ways, and the ideal treatment is highly dependent on their type, location, and symptoms. The two most common types are plexiform neurofibromas (PNs) and cutaneous neurofibromas (cNFs) [1.6.6].
- Plexiform Neurofibromas (PNs): These are often large, complex tumors that grow from multiple nerve bundles. Occurring in about 30-50% of people with NF1, they can cause significant pain, disfigurement, and functional impairment by pressing on surrounding tissues and organs [1.5.2, 1.6.6]. They also carry a risk of transforming into malignant peripheral nerve sheath tumors (MPNST) [1.6.6].
- Cutaneous Neurofibromas (cNFs): These are benign tumors that appear on or just under the skin. While not life-threatening, they affect over 95% of adults with NF1 and can cause significant cosmetic concerns, itching, and pain, impacting quality of life [1.4.6].
Because of these differences, there is no single best medicine. Treatment is tailored to the specific tumor type and patient needs.
FDA-Approved Medications for Plexiform Neurofibromas
In recent years, significant breakthroughs have occurred in the pharmacological treatment of PNs, specifically with a class of drugs called MEK inhibitors. These drugs work by blocking the MEK1 and MEK2 enzymes in the MAPK signaling pathway, which is dysregulated in NF1 and drives tumor growth [1.3.2, 1.9.1].
Selumetinib (Koselugo)
In 2020, selumetinib (Koselugo) became the first FDA-approved medication for treating NF1 [1.2.4]. It is approved for pediatric patients aged one year and older with symptomatic, inoperable plexiform neurofibromas [1.2.2]. Clinical trials demonstrated that over 70% of patients experienced tumor volume reduction, along with improvements in pain, mobility, and quality of life [1.2.1].
- Mechanism: Selumetinib inhibits MEK1 and MEK2, thereby arresting the signaling pathway that promotes cell proliferation and survival [1.3.3].
- Common Side Effects: Side effects can include diarrhea, vomiting, rash, fatigue, musculoskeletal pain, and abdominal pain [1.8.4]. More serious potential side effects include heart problems (cardiomyopathy) and eye toxicity, requiring regular monitoring by a healthcare provider [1.8.5].
Mirdametinib (Gomekli)
In February 2025, the FDA approved a second MEK inhibitor, mirdametinib (Gomekli) [1.7.5]. This was a landmark approval as it is indicated for both adult and pediatric patients (age 2 and older) with symptomatic, inoperable PNs [1.9.5, 1.2.1]. In its pivotal trial, mirdametinib demonstrated significant tumor volume reductions and clinically meaningful improvements in pain and quality of life [1.9.2].
- Mechanism: Like selumetinib, mirdametinib is a MEK1/2 inhibitor that disrupts the MAPK pathway [1.9.1].
- Common Side Effects: The most common treatment-related side effects include acne-like rash, diarrhea, and nausea [1.9.2, 1.9.3].
What About Cutaneous Neurofibromas (cNFs)?
As of late 2025, there are no FDA-approved medications (systemic or topical) specifically for treating or preventing cutaneous neurofibromas [1.4.1, 1.4.6]. Management of cNFs remains focused on procedural removal for cosmetic reasons or symptom relief.
Available procedural options include [1.4.1, 1.4.2]:
- Surgical Excision: Effective for larger tumors or those in sensitive areas, but leaves scars.
- Laser Ablation (e.g., CO2 laser): Can treat many tumors at once but carries a risk of scarring and pigmentation changes.
- Electrodessication: Uses electrical currents to destroy small tumors.
Research into medicinal therapies is ongoing. Clinical trials are investigating topical MEK inhibitors, like NFX-179 gel, which have shown some promise in reducing phosphorylated ERK levels in tumors [1.4.6]. However, the side effect profile of systemic drugs like selumetinib has been found to be less tolerable for adults with cNFs, which are not life-threatening [1.4.6].
Comparison of Neurofibroma Treatment Approaches
| Treatment | Target Tumor Type | Primary Mechanism | Availability |
|---|---|---|---|
| Selumetinib (Koselugo) | Plexiform (inoperable) | MEK Inhibition | FDA-Approved for children ≥1 year [1.2.2] |
| Mirdametinib (Gomekli) | Plexiform (inoperable) | MEK Inhibition | FDA-Approved for adults & children ≥2 years [1.9.5] |
| Surgery | All Types (if operable) | Physical Removal | Standard Practice [1.4.1] |
| Laser / Electrodessication | Cutaneous | Physical Destruction | Standard Practice [1.4.2] |
| Other MEK Inhibitors | Plexiform / Other | MEK Inhibition | Clinical Trials (e.g., Trametinib) [1.5.1, 1.7.4] |
| Topical Medications | Cutaneous | Varies (e.g., MEK inhibition) | Clinical Trials (e.g., NFX-179) [1.4.6] |
The Future: What's on the Horizon?
Research continues to accelerate, offering hope for new and better treatments. The pipeline includes:
- More MEK Inhibitors: Studies on drugs like trametinib for PNs are ongoing to see if they offer similar benefits with fewer side effects [1.5.1].
- Topical Treatments for cNFs: The development of effective topical gels to prevent or shrink skin tumors is a major research focus [1.4.6].
- Combination Therapies: Researchers are exploring combining MEK inhibitors with other drugs to enhance their effectiveness or overcome resistance [1.7.4].
- Gene Therapy: In the long term, correcting the underlying NF1 gene mutation is the ultimate goal, though this technology is still in early development [1.4.1].
For the most current information on new treatments, consulting a specialist and exploring clinical trial databases is recommended.
Conclusion
The question, "What is the best medicine for neurofibroma?" has a nuanced answer that has evolved significantly. For individuals with symptomatic, inoperable plexiform neurofibromas, MEK inhibitors like selumetinib and mirdametinib represent the current best medicinal options, offering the ability to shrink tumors and improve quality of life [1.2.1, 1.5.1]. For cutaneous neurofibromas, the best treatment remains procedural, as no medications have yet been approved [1.4.1]. The choice of therapy must be individualized after a thorough evaluation by a healthcare professional specializing in neurofibromatosis.
