No ADA in monkeys (0.1-1 mg/kg/week); injection-site hypersensitivity-type skin reactions in rats and monkeys at all doses
“Fitusiran increased the incidence of hypersensitivity reactions (skin redness/dryness/scab/discharge at the injection site) in rats and monkeys at all doses tested.”
No ADA in monkeys at 0.1-1.0 mg/kg/week, including after 8-week recovery
“Antidrug antibodies (ADAs) were not detected in any monkey administered fitusiran at doses ranging from 0.1 to 1.0 mg/kg/week during the dosing period or following an 8-week recovery period.”
3.4% (10 of 290 adults), low-titer and mostly transient; no clinically significant effect
“During QFITLIA treatment (up to 250 weeks) in four studies, 10 out of 290 adults with hemophilia (3.4%) developed ADAs. All patients had low ADA titers, and the majority of patients had transient ADAs.”
Main pharmacology-related risk is increased susceptibility to infections (C5 inhibition); no complement activation by the aptamer in monkeys; panuveitis with Lucentis combination