Effectiveness and safety of liposomal rapamycin for the treatment of facial angiofibromas in tuberous sclerosis.

Aim: Topical rapamycin is the pharmacological treatment of choice for facial angiofibromas in rare tuberous sclerosis disease. A new, more advanced, and complex formula was developed in our pharmacy service: rapamycin 0.4% liposomal formulation, with better organoleptic characteristics and a more favorable release profile of the active ingredient. The purpose of this study is to evaluate the effectiveness and safety of liposomal topical rapamycin for the treatment of facial injuries in this rare disease.

Method: This was an observational, prospective, and multicenter study. Effectiveness was evaluated mainly through facial angiofibromas severity index (FASI), investigator's global assessment (IGA) scores, and dermatology life quality index (DLQI) questionnaire. To assess the safety profile of rapamycin, adverse reactions were reported, and blood tests and blood rapamycin levels were performed during treatment.

Results: Eleven patients were included, of which 8/11 (73%) patients obtained successful treatment according to FASI and IGA scores after 24 weeks of treatment. Statistical analysis demonstrated a significant improvement (p<.05) in FASI and IGA scores, erythema, and FA size after treatment with rapamycin liposomal formulation (FASI before treatment, median (interquartile range): 6.0 (2.0), FASI after treatment: 3.5 (2.0), p=.0063). Five patients also improved their quality of life after treatment. Regarding safety profile of rapamycin, the most common adverse reaction was mild pruritus and 2 patients reported erythema, who discontinued treatment prematurely. All hematological tests were normal, and blood rapamycin levels were undetectable.

Conclusions: After galenic improvements and clinical evaluations, the rapamycin liposomal formulation proved to be effective and safe for this therapeutic indication. This new formulation was included as a magistral formula in our hospital pharmacy service, now accessible for prescribing by dermatologists. Drug development in hospital pharmacy is often the only pharmacological alternative available to treat the symptoms of rare diseases, when treatment options are limited or inadequate.