Inclusion Criteria:

1. Clinically definite diagnosis of NF1 according to the NIH consensus conference
criteria.

2. Patients must have PN that have the potential to cause significant morbidity, such as
lesions that could compromise the airway or the great vessels, lesions that could
cause nerve compression, lesions that could result in major deformity or significant
cosmetic problems

3. Measurable disease: patient must have at least one measurable PN amenable to
volumetric MRI analysis.

Exclusion Criteria:

1. Chronic treatment with systemic steroids or another immunosuppressive agent.

2. Evidence of an active optic glioma, malignant glioma, malignant peripheral nerve
sheath tumor, or other cancer requiring treatment with chemotherapy or radiation
therapy.

3. Clinical evidence of significantly impaired lung function

4. Pregnancy or breast feeding.

5. Prior therapy with mTOR inhibitors (e.g.sirolimus, temsirolimus, everolimus).

6. No contraindications for MRI assessments

Other protocol-defined inclusion/exclusion criteria may apply