Expert: Small interfering RNA (siRNA) targeting antithrombin mRNA in hepatocytes. Reduces antithrombin protein levels by ~80%, shifting the hemostatic balance toward thrombin generation. Works independently of the intrinsic pathway (FVIII/FIX), effective in both hemophilia A and B, with or without inhibitors.

Everyday: Silences the gene that makes a natural blood thinner. Antithrombin normally prevents excessive clotting — useful for healthy people, but bad for hemophilia patients who can't clot enough. This drug uses RNA interference to tell the liver to stop making antithrombin, tipping the balance toward clotting.

Targets: []

First-in-class anti-antithrombin siRNA. Approved Mar 2025 for Hem A/B +/- inhibitors. Unique MOA: silences antithrombin gene via RNAi, rebalancing hemostasis. Key advantage: only 6 injections/year (Q2M). Key disadvantage: requires antithrombin monitoring, prothrombotic risk. Works in BOTH Hem A and Hem B.