No cytokine or immunophenotype effects; transient ~2-fold C3 rise at high dose in mouse; no anti-drug antibodies
“There were no drug effects on C3 after dosing on Day 0; however, on Day 175, there was an approximate 2-fold elevation in serum C3 24 h after dosing in HDM.”
✓ VerifiedFDA pharmacology/toxicology review, p. 24Source ↗
Biodistribution & persistence
Radiolabel in monkey: highest in kidney cortex, low skeletal muscle levels; low protein binding
“With multiple doses (20 mg/kg/week for 8 weeks), highest levels of dose radioactivity were in kidney cortex (819 µg-Eq/g), with concentrations in skeletal muscle of 0.331- 0.479 µg-Eq/g.”
✓ VerifiedFDA pharmacology/toxicology review, p. 3Source ↗
Modality-specific risk
PMO renal tubular toxicity (nephrotoxicity, deaths in mouse); off-target hybridization (APCDD1) assessed in silico
“Kidney toxicity in the pivotal study, which resulted in unscheduled death of two HDM, was characterized by slight increases in urea nitrogen and creatinine, increases in kidney weight in HDM, and histologic findings of intratubular dilation and epithelial vacuolation in the distal tubule and collecting duct in MDM and HDM.”
✓ VerifiedFDA pharmacology/toxicology review, p. 47Source ↗
Anti-drug antibodies: animals
Anti-drug antibodies not detected in the 26-week mouse study
“Increases in Cmax and AUC were dose-proportional. Anti-drug antibodies were not detected.”
✓ VerifiedFDA pharmacology/toxicology review, p. 24Source ↗
Anti-drug antibodies: patients
No anti-viltolarsen antibodies: all samples from 16 patients negative in Study 1
“For Study 1, samples collected from all 16 patients at Day 1 (pre-dose), Week 5, Week 13, and Week 24 were assessed for anti-viltolarsen antibodies. All samples were determined to be antibody negative.”
Main pharmacology-related risk is increased susceptibility to infections (C5 inhibition); no complement activation by the aptamer in monkeys; panuveitis with Lucentis combination