Arteritis in high-dose males attributed to ADA-mediated immune complex deposition (anifrolumab, IgM, C3b)
“The arteritis could be due to the deposit of ADA-mediated immunocomplexes based on positive staining of anifrolumab, monkey IgM, and complement component 3b (C3b) but not monkey IgG from kidney samples of 2 HD-IV monkeys with arteritis.”
✓ VerifiedFDA multi-discipline review, p. 46Source ↗
Biodistribution & persistence
Infant monkey serum on day 30 after birth 4.2-9.7% of maternal concentrations
“In the infants, mean serum concentrations of anifrolumab‑fnia on Day 30 after birth increased with dose and were approximately 4.2% to 9.7% of the respective maternal concentrations.”
Type I IFN blockade: plausible increased cancer risk given IFN anti-tumour role
“Type I interferons have a role in the anti-tumour response. Thus, it is plausible that blockade of IFNAR1 responses would potentially increase the risk of”
39-week study: ADA in 11/48 (22.9%) treated monkeys, higher incidence at lower doses
“Anti-drug antibodies were detected in 11/48 (22.9%) animals treated with anifrolumab with higher incidence observed in animals receiving lower doses.”
ADA 2.6% (9/350) with recommended IV dosing for up to 4 years
“In Trials 2, 3, and the long-term extension trial, treatment emergent anti-anifrolumab-fnia antibodies were detected in 9 of 350 patients (ADA incidence 2.6%) who received SAPHNELO at the recommended intravenous dosing regimen for up to 4 years.”
In vitro whole-blood cytokine release far below alemtuzumab/TGN1412 controls; no effects on monkey TDAR, lymphocyte subsets or serum cytokines; ADA in some monkeys