Paik, Julie J.

Abstract Dermatomyositis is driven by overactivation of type I and II interferons and other proinflammatory cytokines that signal via the JAK-STAT pathway. We conducted a 12-week, open-label study of brepocitinib, an oral TYK2/JAK1 inhibitor, in five adults with severe cutaneous dermatomyositis. Treatment was associated with rapid, clinically meaningful improvement in cutaneous disease activity. Single-cell and spatial transcriptomic profiling of lesional skin showed marked suppression of interferon-responsive pathways and inflammatory cell states by week 4. Together with findings from a Phase 3 randomized trial in DM patients with skin and muscle involvement (VALOR, NCT05437263 ), these data support TYK2/JAK1 inhibition as a promising therapeutic strategy for DM.

Objective This study aims to identify factors associated with patient global assessment (PtGA) and physician global assessment (PhGA) and discordance between them in systemic sclerosis (SSc). Methods Data from adults with early SSc (<5 years) from the Collaborative National Quality and Efficacy Registry were included. PtGA and PhGA (0–10 scale), clinical evaluations, and patient‐reported outcomes (PROs) were collected every six months. Multivariable mixed‐effects linear regression identified factors associated with PtGA and PhGA using (1) clinical variables and (2) clinical variables plus PROs. Relative weight analysis (RWA) determined the relative importance of each variable. Discordance (≥2 points between PtGA and PhGA) was assessed using multinomial mixed‐effects logistic regression. Results Among 956 patients (83% women, 33% limited disease), mean PtGA and PhGA at enrollment were 4.2 (SD 2.6) and 3.4 (SD 2.0), respectively ( P < 0.001). RWA of clinical variables identified modified Rodnan skin score (mRSS) and New York Heart Association (NYHA) functional class as most influential for both global assessments. After including PROs, PtGA was most influenced by measures of pain, skin symptoms, and physical function. Discordance occurred in 53% of patients (35% PtGA worse, 18% PhGA worse). Worse PtGA was associated with higher overall pain and discomfort. Worse PhGA was associated with higher mRSS, worse NYHA class, higher pain interference, and lower diffusing capacity of the lung. Conclusion Discordance between PtGA and PhGA occurs commonly, highlighting the need for comprehensive symptom management and measurement of disease burden in this complex disease. In SSc, differences in PtGA and PhGA reflect dissimilar weighting of data elements.

Abstract Somatic mutations in UBA1 cause vacuoles, E1 ubiquitin-activating enzyme, X-linked, autoinflammatory somatic (VEXAS) syndrome, an adult-onset inflammatory disease with an overlap of hematologic manifestations. VEXAS syndrome is characterized by a high mortality rate and significant clinical heterogeneity. We sought to determine independent predictors of survival in VEXAS and to understand the mechanistic basis for these factors. We analyzed 83 patients with somatic pathogenic variants in UBA1 at p.Met41 (p.Met41Leu/Thr/Val), the start codon for translation of the cytoplasmic isoform of UBA1 (UBA1b). Patients with the p.Met41Val genotype were most likely to have an undifferentiated inflammatory syndrome. Multivariate analysis showed ear chondritis was associated with increased survival, whereas transfusion dependence and the p.Met41Val variant were independently associated with decreased survival. Using in vitro models and patient-derived cells, we demonstrate that p.Met41Val variant supports less UBA1b translation than either p.Met41Leu or p.Met41Thr, providing a molecular rationale for decreased survival. In addition, we show that these 3 canonical VEXAS variants produce more UBA1b than any of the 6 other possible single-nucleotide variants within this codon. Finally, we report a patient, clinically diagnosed with VEXAS syndrome, with 2 novel mutations in UBA1 occurring in cis on the same allele. One mutation (c.121 A&gt;T; p.Met41Leu) caused severely reduced translation of UBA1b in a reporter assay, but coexpression with the second mutation (c.119 G&gt;C; p.Gly40Ala) rescued UBA1b levels to those of canonical mutations. We conclude that regulation of residual UBA1b translation is fundamental to the pathogenesis of VEXAS syndrome and contributes to disease prognosis.