Correlation of pharmacodynamic activity, pharmacokinetics, and anti-product antibody responses to anti-IL-21R antibody therapeutics following IV administration to cynomolgus monkeys

Table 4 Formation of neutralizing anti-Ab-02 antibodies (log Titer) after a single 10 mg/kg IV dosage of Ab-02 to cynomolgus monkeys

TIME (DAYS)	ANIMAL 4	ANIMAL 5	ANIMAL 6
Pre-dose	Negative	Negative	Negative
15	Negative	Negative	Negative
22	4.12	2.7	2.2
36	2.2	2.7	2.7

Formation of neutralizing anti-Ab-02 was assessed using a flow cytometric assay, in which serum samples from Ab-02 dosed monkeys were tested for inhibition (relative to pre-dose) of anti-IL-21R-biotin binding to TF-1 cells transfected with human IL-21R. Negative samples had no inhibition at the minimum required dilution of 1:6 and had a log titer < 0.78.

ISSN: 1479-5876