In vitro cytokine release (IL-6, TNF-α, IFN-γ) varied by assay format, greatest in solid-phase PBMC assays
“Results of the cytokine release assays varied by the experimental conditions; mogamulizumab generally caused greater cytokine release (IL-6, TNF-α, and IFN-γ) in solid phase assays with isolated PBMCs.”
✓ VerifiedFDA multi-discipline review, p. 24Source ↗
Biodistribution & persistence
Placental transfer: fetal plasma exposure ~60% of maternal in monkeys
“At the end of the study plasma exposure of mogamulizumab in the fetuses was ~60% that observed in the dams; this finding is consistent with the expected transfer of mogamulizumab across the placental barrier.”
✓ VerifiedFDA multi-discipline review, p. 24Source ↗
Modality-specific risk
Dermatologic adverse events in patients not predicted by monkey repeat-dose studies
“Dermatologic adverse events (AE) were observed in humans that were not predicted by the repeat-dose toxicity studies in cynomolgus monkeys.”
✓ VerifiedFDA multi-discipline review, p. 23Source ↗
Anti-drug antibodies: animals
ADA in only 1 monkey in 26-week study; ADA-positive animals showed faster decline in drug concentration
“In the 26-week repeat-dose study, development of anti-mogamulizumab antibodies was observed in only one animal (1 female in the 2.5 mg/kg group). The plasma mogamulizumab concentrations of the animals in which anti-mogamulizumab antibodies were observed decreased more rapidly than the plasma concentration in animals that did not produce anti-mogamulizumab antibodies.”
14.1% (44/313) ADA-positive; no neutralizing antibodies; no clinically significant effect
“Among 313 patients treated with POTELIGEO and whose antibodies were tested, 44 (14.1%) tested positive for anti-mogamulizumab-kpkc antibodies. There was no identified clinically significant effect of anti-drug antibodies on pharmacokinetics, safety, or effectiveness of POTELIGEO. There were no positive neutralizing antibody responses.”
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