Rat QWBA: highest in liver, lymph nodes, kidneys; detectable in all tissues at 672 h; not in fetal tissue
“Based on the QWBA data, radioactivity in tissues generally peaked by 48 hours postdose, and was highest in liver, lymph nodes, kidneys, and thoracic ducts.”
✓ VerifiedFDA pharmacology/toxicology review, p. 29Source ↗
Modality-specific risk
On-target vitamin A and thyroxine reduction (DART relevance); rat hepatocellular changes and renal basophilic granules
“vutrisiran was demonstrated to reduce circulating Vitamin A levels in monkey and human, consistent with TTR protein being a major carrier of Vitamin A.”
✓ VerifiedFDA pharmacology/toxicology review, p. 5Source ↗
Anti-drug antibodies: animals
Rat (6-month): no ADA; monkey (9-month): ADA in eight of 32, no impact on pharmacology, TK or toxicity
“No anti-drug-antibodies (ADAs) were discovered in the 6 months toxicity study in rats, whereas eight of the 32 monkeys in the 9 months chronic toxicity study developed ADAs that did not impact on the pharmacology, toxicokinetic or toxicity of vutrisiran.”
Treatment-emergent ADA in 4/179 (2.2%); no impact on PK, PD, efficacy or safety
“Across Study 001 and HELIOS-A, the incidence of treatment-emergent ADA due to vutrisiran was 2.2% (4/179). The presence of ADA had no impact on the PK, PD, efficacy, or safety of vutrisiran.”
Main pharmacology-related risk is increased susceptibility to infections (C5 inhibition); no complement activation by the aptamer in monkeys; panuveitis with Lucentis combination