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Small nuclear RNAs (snRNAs) combine with specific proteins to generate small nuclear ribonucleoproteins (snRNPs), the building blocks of the spliceosome. U4 snRNA forms a duplex with U6 and, together with U5, contributes to the tri-snRNP spliceosomal complex. Variants in RNU4-2, which encodes U4, have recently been implicated in neurodevelopmental disorders. Here we show that heterozygous inherited and de novo variants in RNU4-2 and in four RNU6 paralogs (RNU6-1, RNU6-2, RNU6-8 and RNU6-9), which encode U6, recur in individuals with nonsyndromic retinitis pigmentosa (RP), a genetic disorder causing progressive blindness. These variants cluster within the three-way junction of the U4/U6 duplex, a site that interacts with tri-snRNP splicing factors also known to cause RP (PRPF3, PRPF8, PRPF31), and seem to affect snRNP biogenesis. Based on our cohort, deleterious variants in RNU4-2 and RNU6 paralogs may explain up to ~1.4% of otherwise undiagnosed RP cases. This study highlights the contribution of noncoding RNA genes to Mendelian disease and reveals pleiotropy in RNU4-2, where distinct variants underlie neurodevelopmental disorder and retinal degeneration.

Importance:Intensive lowering of low-density lipoprotein cholesterol (LDL-C) levels with PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors for cardiovascular event reduction has largely been reserved for patients with significant atherosclerosis. Objective:To investigate whether evolocumab could prevent a first major cardiovascular event (MACE) in patients without known significant atherosclerosis. Design, Setting, and Participants:VESALIUS-CV was a randomized, double-blind, placebo-controlled trial of evolocumab conducted across 774 sites in 33 countries and enrolling 12 257 patients with no prior myocardial infarction or stroke, LDL-C level 90 mg/dL or greater, and qualifying atherosclerosis or high-risk diabetes. This prespecified subgroup analysis examined outcomes in patients without known significant atherosclerosis (none of the following: prior arterial revascularization, arterial stenosis ≥50%, or coronary artery calcium score ≥100 Agatston units), all of whom had diabetes. Enrollment started in June 2019 and the last patient visit was July 2025, with a median follow-up of 4.8 years. Intervention:Patients were randomized in a 1:1 ratio to subcutaneous administration of either evolocumab (140 mg every 2 weeks) or matching placebo added to optimally tolerated statin therapy. Main Outcomes and Measures:The dual primary end points were composites of coronary heart disease death, myocardial infarction, or ischemic stroke (3-P MACE) and 3-P MACE plus ischemia-driven arterial revascularization (4-P MACE). Secondary end points included all-cause mortality. Results:This predefined subgroup included 3655 patients (1849 in the evolocumab group and 1806 in the placebo group) with a median age of 65 years (57% female). Among those in the lipid substudy, the median LDL-C level at 48 weeks was 52 mg/dL in the evolocumab group vs 111 mg/dL in the placebo group (P < .001). A 3-P MACE event occurred in 83 patients (5-year Kaplan-Meier estimate, 5.0%) in the evolocumab group compared with 117 patients (5-year Kaplan-Meier estimate, 7.1%) in the placebo group (hazard ratio [HR], 0.69 [95% CI, 0.52-0.91]; P = .009; between-group difference, 2.1% [95% CI, 0.4%-3.8%]). A 4-P MACE event occurred in 127 patients (5-year Kaplan-Meier estimate, 7.6%) in the evolocumab group compared with 178 patients (5-year Kaplan-Meier estimate, 10.5%) in the placebo group (HR, 0.69 [95% CI, 0.55-0.86]; P = .001; between-group difference, 2.9% [95% CI, 0.9%-4.9%]). There were 136 deaths (5-year Kaplan-Meier estimate, 7.8%) in the evolocumab group compared with 172 deaths (5-year Kaplan-Meier estimate, 10.1%) in the placebo group (HR, 0.76 [95% CI, 0.61-0.95]). Conclusions and Relevance:In high-risk patients without known significant atherosclerosis and with diabetes, evolocumab reduced the risk of a first major cardiovascular event. Trial Registration:ClinicalTrials.gov Identifier: NCT03872401.

Mediation analysis is a useful tool to evaluate surrogate endpoints in clinical trials. We propose a novel method, the M-survival learner, for estimating heterogeneous indirect treatment effects in the presence of censored outcomes. The proposed approach enables the identification of interpretable patient subgroups characterized by distinct mediation pathways. To distinguish heterogeneous from homogeneous mediation effects, we introduce a new statistical criterion specifically designed for survival data. The method provides a principled framework for evaluating heterogeneity in surrogate biomarker performance across patient populations, offering evidence to support accelerated approval drug. By explicitly assessing subgroup-specific surrogate validity, the proposed approach addresses key regulatory concerns regarding the reliability of surrogate endpoints. We further establish theoretical properties of the method to justify its statistical guarantees. We apply the approach to data from a Phase III randomized clinical trial of HIV treatment, demonstrating its practical utility in real-world settings. Extensive simulation studies further evaluate and demonstrate its finite-sample performance.

Vascular smooth muscle cell (VSMC) diversification drives atherosclerotic coronary artery disease (CAD). Mechanisms governing these cell state transitions remain unclear. We applied multiomic single-cell profiling, epitope mapping, and spatial transcriptomics across 27 human coronary arteries, identifying fibroblast activation protein (FAP) as a marker of modulated VSMCs. Lineage tracing in mice indicated that FAP+ cells originate from Myh11+ VSMCs, and FAP PET imaging in CAD patients showed plaque uptake. FAP+ cells states resided in the macrophage-rich neo-intima. Therapeutically, we developed an anti-FAP bispecific T-cell engager, which reduced plaque burden and remodeled the stromal-immune microenvironment through T-cell clonal expansion. Our study delivers a single-cell and spatial atlas of human CAD, establishes FAP as a marker of modulated VSMCs, and highlights immunotherapy for lipid-independent targets.

BACKGROUND:Chemotherapy-induced thrombocytopenia (CIT) is a common complication of chemotherapy that is associated with bleeding, reduced relative dose intensity, and potentially worse outcomes. No widely available therapies are approved for CIT. METHODS:We conducted a phase 3, international, double-blind, randomized, placebo-controlled trial involving patients with persistent CIT (platelet count, ≤85×109 per liter on trial day 1) who were receiving oxaliplatin-based multiagent cytotoxic chemotherapy for gastrointestinal cancers. Patients were randomly assigned in a 2:1 ratio to receive romiplostim or placebo for three chemotherapy cycles. The primary end point was the absence of CIT-induced modifications of the chemotherapy dose (reduction, delay, omission, or discontinuation) in both the second and third chemotherapy cycles. RESULTS:Of the 165 patients who underwent randomization (109 in the romiplostim group and 56 in the placebo group), 75% had colorectal cancer, 13% had gastroesophageal cancer, and 12% had pancreatic cancer; 72% of the patients in the romiplostim group and 61% of those in the placebo group had stage 4 disease. The percentage of patients with no CIT-induced modifications of the chemotherapy dose was 84% (92 of 109 patients) with romiplostim and 36% (20 of 56 patients) with placebo, which corresponded to an odds ratio of 10.16 (95% confidence interval [CI], 4.44 to 23.72; P<0.001) and a risk ratio of 2.77 (95% CI, 1.78 to 4.30; P<0.001). Adverse events of grade 3 or higher occurred in 37% of the patients who received romiplostim and in 22% of those who received placebo, which primarily reflected chemotherapy effects. Adverse events that were considered by the investigator to be related to romiplostim or placebo occurred in 12% of patients who received romiplostim and in 7% who received placebo, with the most frequent being nausea (2% in each group) and headache (2% in the romiplostim group); none were serious or led to death or discontinuation of romiplostim, placebo, or chemotherapy. Thromboembolic events occurred in 2% of patients who received romiplostim and in no patients who received placebo. CONCLUSIONS:In this phase 3, placebo-controlled trial, romiplostim was efficacious in treating CIT. (Funded by Amgen and the Biomedical Advanced Research and Development Authority; RECITE ClinicalTrials.gov number, NCT03362177.).