Vss about 50 mL/kg in monkeys, similar to plasma volume; limited extravascular distribution
“The volume of distribution (Vss) estimated in the PK study (108662) in cynomolgus monkey was approximately 50 mL/kg which is similar to the plasma volume and demonstrated limited extravascular distribution.”
Unknown malignancy risk from chronic TSLP inhibition
“the malignancy risk in humans by chronic inhibition of TSLP via tezepelumab treatment is currently unknown.”
✓ VerifiedFDA multi-discipline review, p. 34Source ↗
Anti-drug antibodies: animals
ADA formed in monkeys but did not affect exposure; no effect on toxicology evaluation
“The formation of ADA did not affect exposure to tezepelumab during the dosing phase, and because all surviving animals maintained levels of bioactive drug, there was no effect on the toxicologic evaluation of tezepelumab.”
Asthma: ADA in 5% (29/601); treatment-emergent 2% (11); neutralizing in 1 patient (<1%)
“In patients with asthma (NAVIGATOR and an additional trial), anti-drug antibodies (ADA) were detected at any time in 29 (5%) out of 601 patients who received TEZSPIRE at the recommended dosing regimen during the 48 to 52‑week study period. Of these 29 patients, 11 patients (2% of patients treated with TEZSPIRE) developed treatment-emergent antibodies and 1 patient (<1% of patients treated with TEZSPIRE) developed neutralizing antibodies.”
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