BASICS Trial: Baricitinib 4 mg Significantly Reduces Skin Fibrosis in Systemic Sclerosis
View StudyPlain-Language Summary
A 2025 randomized trial published in Clinical Rheumatology found that baricitinib, a JAK1/2 inhibitor already approved for rheumatoid arthritis, significantly reduced skin thickening in patients with systemic sclerosis (scleroderma). The high-dose group receiving 4 mg daily saw their modified Rodnan skin score drop by an average of 8.9 points at 12 weeks, compared to only 3.6 points in the control group. These findings suggest JAK inhibition may offer a meaningful new treatment pathway for scleroderma, a disease with very limited approved options.
Abstract
Systemic sclerosis (SSc), or scleroderma, is a rare autoimmune disease characterized by immune dysregulation, widespread fibrosis of the skin and internal organs, and vascular damage. Treatment options remain limited and no disease-modifying therapy has been broadly approved specifically for the skin manifestations of SSc. Baricitinib, a selective JAK1/2 inhibitor, has established efficacy in rheumatoid arthritis and dermatomyositis, and preclinical evidence suggests the JAK-STAT signaling pathway contributes to SSc-related immune activation and fibrosis.
The BASICS trial was a prospective, open-label, randomized study enrolling 48 adults with systemic sclerosis between April 2021 and January 2022. Participants were randomly assigned to baricitinib 4 mg daily, baricitinib 2 mg daily, or a control group for 24 weeks. The primary outcome was change in modified Rodnan skin score (mRSS), a validated composite measure of skin fibrosis, from baseline to week 12. Secondary outcomes included ACR-CRISS score, forced vital capacity, systemic sclerosis composite score, tender and swollen joint counts, digital ulcer burden, quality of life as measured by EQ-5D, and safety assessments at weeks 12 and 24. Transcriptomic analysis of blood samples before and after treatment was also performed.
The mean change in mRSS from baseline to week 12 was -8.9 in the baricitinib 4 mg group, -3.8 in the 2 mg group, and -3.6 in the control group (P = 0.019), with the 4 mg dose demonstrating statistically significant superiority over control. The safety profile was acceptable and consistent with the known profile of baricitinib. The authors concluded that baricitinib 4 mg improves skin fibrosis in SSc, likely by modulating JAK-mediated immune and inflammatory pathways, and that these findings support further investigation in larger randomized controlled trials.