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Oral rapamycin: an alternative in children with complicated vascular abnormalities
A Gómez Sánchez1, J V Redondo Sedano1, V Pérez Alonso1
1Pediatric Plastic Surgery Unit. Pediatric Surgery Department. 12 de Octubre University Hospital. Madrid (Spain).
Insights
Oral sirolimus effectively treats pediatric vascular abnormalities, showing significant clinical and radiological improvements in most patients. This mTOR inhibitor offers a safe and beneficial option for complex cases resistant to other therapies.
Area of Science:
- Vascular biology and medicine
- Pediatric oncology and hematology
- Pharmacology and drug discovery
Background:
- Complicated vascular abnormalities pose significant treatment challenges in pediatric patients.
- Sirolimus, an mTOR inhibitor, has emerged as a promising therapeutic agent for these conditions.
- Previous treatments often yield suboptimal outcomes, necessitating novel therapeutic strategies.
Purpose of the Study:
- To evaluate the efficacy and safety of oral sirolimus in a cohort of pediatric patients with complicated vascular abnormalities.
- To review existing literature on sirolimus treatment for similar pediatric conditions.
- To present clinical and radiological outcomes in a series of treated children.
Main Methods:
- Retrospective analysis of pediatric patients treated with oral sirolimus since 2016.
- Standardized dosing (0.8 mg/m2 q12h) and therapeutic drug monitoring (5-15 ng/ml).
- Prophylaxis with trimethoprim-sulfamethoxazole was administered to all patients.
Main Results:
- Six pediatric patients (3 male, 3 female, mean age 9.5 years) with lymphatic, venous, or combined malformations were included.
- Five patients experienced clinical improvement within a mean of 3.6 months; four showed radiological improvement in 6.6 months.
- Mild, transient adverse effects were observed in three patients, with five remaining on treatment.
Conclusions:
- Oral sirolimus demonstrates efficacy and a favorable safety profile for treating complicated pediatric vascular abnormalities.
- The study supports sirolimus as a valuable treatment option for refractory lymphatic and venous malformations.
- Good symptomatic and moderate radiological responses were observed, particularly in cases where prior treatments failed.
Objective:
Sirolimus mTOR inhibitor represents a major advance in the treatment of patients with complicated vascular abnormalities. The objective of this study was to present our series of pediatric patients with vascular abnormalities treated with oral sirolimus, and to conduct a review of the relevant literature.
Material And Methods:
A retrospective analysis of patients with complicated vascular abnormalities treated with oral sirolimus in our healthcare facility from 2016 was carried out. Initial dosage was 0.8 mg/m2 every 12 hours, and therapeutic range was 5-15 ng/ml. All patients received trimethoprim-sulfamethoxazole prophylaxis.
Results:
6 children -3 boys and 3 girls- with a mean age of 9.5 years at treatment initiation were included. 3 of them had head and neck lymphatic malformation, 2 had lower limb venous malformation, and 1 had combined lymphatic-venous malformation at the thoracoabdominal level. They all had received multiple previous treatments without improvement. Following sirolimus initiation, 5 patients had clinical improvement (mean time: 3.6 months) and 4 had radiological improvement (mean time: 6.6 months). Mild and transitory adverse effects were noted in the 3 cases. Today, 5 patients remain under treatment.
Conclusions:
Oral sirolimus is an effective and safe treatment in patients with complicated vascular abnormalities. Our results support sirolimus use in lymphatic and venous malformations in which previous treatments have failed, with a good symptomatic and, to a lesser extent, radiological response.
