Low‑Dose Interleukin‑2 Expands Regulatory T Cells and Modulates Biomarkers in Mild–Moderate Alzheimer’s Disease: Phase 2a Randomized Trial Shows Safety and Promising Signals

Highlights

– Low‑dose subcutaneous IL‑2 (1 x 10^6 IU/day for 5 days) administered every 4 weeks (IL‑2 q4wks) was safe and well tolerated in people with mild–moderate Alzheimer’s disease (AD).

– IL‑2 q4wks significantly expanded circulating regulatory T cells (Tregs) and increased Foxp3 mean fluorescent intensity (MFI), with enhanced suppressive function versus placebo.