N-acetylcysteine reduces disease activity by blocking mammalian target of rapamycin in T cells from systemic lupus erythematosus patients: a randomized, double-blind, placebo-controlled trial

Lai ZW, et al

Published in Arthritis & Rheumatism

Methodology

Randomised, double-blind, placebo-controlled trial of three NAC doses over 3 months in SLE patients, with SLEDAI/BILAG disease activity scoring and flow-cytometric T cell mTOR and regulatory T cell assessment.

Key Findings

In 36 patients with systemic lupus erythematosus, N-acetylcysteine (up to 4.8 g/day) for 3 months reduced SLEDAI and BILAG disease activity scores versus placebo and blocked mTOR activation in T cells, normalising regulatory T cell numbers and reducing anti-DNA antibody-associated activity.

Conclusions

High-dose N-acetylcysteine reduced lupus disease activity and normalised T cell signalling in a small trial, a promising but preliminary signal needing larger confirmatory studies.

Limitations

Small single-centre trial with three dose arms, leaving few patients per group; short 3-month duration; gastrointestinal intolerance at the highest dose; mechanistic endpoints emphasised over hard clinical outcomes; not replicated in a large phase III trial.