Lai ZW, et al. - The safety, tolerance, and efficacy of sirolimus were inspected by the researchers in patients with active systemic lupus erythematosus disease unresponsive to, or intolerant of, conventional medications aged ≥18 years at the State University of New York Upstate Medical University (Syracuse, NY, USA). It was observed that sirolimus expanded CD4⁺CD25⁺FoxP3⁺ regulatory T cells and CD8⁺ memory T-cell populations and inhibited interleukin-4 and interleukin-17 production by CD4⁺ and CD4^-CD8^- double-negative T cells after 12 months. A connection was illustrated between a progressive improvement in disease activity with the correction of pro-inflammatory T-cell lineage specification in such patients during 12 months of sirolimus therapy.