Rytvela acetate, Pathway-Biased IL-1R1 Antagonist acetate

Rytvela (101.10) is a highly cell-permeable, all-D-amino acid heptapeptide engineered to confer absolute protease resistance and structural stability, mimicking the flexible extracellular IL-1RAcP D3-juxtamembranous loop to non-competitively antagonize the interleukin-1 receptor (IL-1R1) complex with exceptional quantitative potency (IC50 ≈ 0.5–2.0 nM; KD = 5 nM). Binding an allosteric pocket distinct from the orthosteric site ensures exquisite IL-1R1 specificity, demonstrated by zero functional efficacy in knockout models and an absence of cross-reactivity with IL-18, IL-6, or TNF-α pathways. By exerting targeted functional selectivity, the reversible biased ligand potently ablates downstream SAPK/JNK, AP-1, and RhoA/ROCK signaling while critically sparing cytoprotective NF-κB activation, thereby circumventing the severe apoptotic toxicity characteristic of global IL-1 blockade induced by indiscriminate orthosteric biologics. Displays superior penetrance across placental, blood-retinal, and epithelial barriers, enabling rytvela to suppress pathogenic Sema3A, MMP9, and CCL2 expression, revert amoeboid microglia to a resting ramified state, prevent endothelial apoptosis, block vascular vaso-obliteration, and abolish pathogenic uterine contractility. Proving highly efficacious whether administered systemically (1 mg/kg IV, SC, IP) or locally (1 mg/kg/day intrarectal; 100 nM topical), rytvela rapidly reverses IL-1-induced hyperthermia, TNBS-induced inflammatory bowel disease, contact dermatitis, OIR-induced retinopathy, and LPS/LTA-induced preterm birth. Ultimately, the novel heptapeptide establishes a translatable, precision-engineered therapeutic paradigm for compartmentalized inflammatory diseases without compromising baseline host defenses.

Hygroscopic, Store with desiccant