Efficacy and Safety of Thalidomide for Pediatric PFAPA Syndrome

Efficacy and Safety of Thalidomide in Treating Pediatric PFAPA Syndrome: A Multicenter Randomized Controlled Trial

The goal of this clinical trial is to evaluate the efficacy and safety of thalidomide in the treatment of children with Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Adenitis (PFAPA) syndrome. The study focuses on children diagnosed with PFAPA syndrome. The main questions it aims to answer are:

Can thalidomide significantly reduce the frequency of febrile episodes in children with PFAPA syndrome? What is the safety profile and tolerability of thalidomide in this pediatric population? Researchers will compare the thalidomide group to a colchicine group to see if thalidomide is more effective in controlling recurrent fever and associated symptoms.

Participants will:

Take the assigned medication (thalidomide or colchicine) daily for a duration of 6 months.

Attend follow-up visits every 4 weeks at the clinic. Maintain a diary to record the frequency of fever episodes and any other clinical symptoms.

Undergo safety assessments and physical examinations during each scheduled visit.

Inclusion Criteria:

1. Meet the 2019 Eurofever or 2020 CARRA diagnostic criteria for PFAPA syndrome.
2. Aged 3 to 18 years (inclusive) at the time of screening.
3. Have experienced at least 3 febrile episodes within the past six months.
4. History of responsiveness to glucocorticoid treatment during at least 3 previous episodes, but with continued recurrence. (Responsiveness is defined as normalization of body temperature within 24 hours after a maximum dose of 2 mg/kg [up to 60 mg] administered as a single or two divided doses).

Exclusion Criteria:

1.Diagnosis of monogenic or other polygenic periodic fever syndromes. 2.Presence of immunodeficiency or neoplastic diseases. 3.Active bacterial, fungal, or viral infection during the screening period. 4.Prior treatment with immunosuppressive agents. 5.Prior use of thalidomide or colchicine. 6.Laboratory parameters at screening that meet any of the following (based on the most recent test result at the study hospital prior to the first dose):

1. White Blood Cell (WBC) count < 4 × 10⁹/L, Hemoglobin (HGB) < 100 g/L, or Platelet (PLT) count < 100 × 10⁹/L.
2. Serum Alanine Aminotransferase (ALT) > 2 times the Upper Limit of Normal (ULN).
3. Glomerular Filtration Rate (GFR/CCR) < 60 mL/min/1.73m².