Highly immunogenic in monkeys (ADA in most studies); no major immunomodulatory changes; no dedicated immunotoxicity studies
“Studies on immunomodulatory effects were incorporated in some pharmacology and toxicology studies in cynomolgus monkeys. These studies did not reveal any major differences compared to controls.”
Wide distribution in monkey without bone sequestration; limited BBB, testis and placental crossing
“There were indications that denosumab has limited potential to cross the blood/brain barrier, the blood/testis barrier as well as the placental barrier, although this data is confounded by the presence of radiolabel in blood vessels and an unknown contribution of free radiolabel.”
“RANK/RANKL knockout mice also exhibited absence of lymph node formation, as well as an absence of lactation due to inhibition of mammary gland maturation (lobulo-alveolar gland development during pregnancy)”
High ADA incidence in monkeys; antibodies markedly increased denosumab elimination, confounding high-dose PK
“In general, the high percentage of animals developing anti-drug-antibodies impacted the PK analysis. Especially at the high dose range, the PK data need to be interpreted with caution. The formation of these antibodies appeared to markedly increase the rate of elimination of denosumab.”
<1% (55/8113) binding antibodies over up to 5 years; no neutralizing antibodies
“Using an electrochemiluminescent bridging immunoassay, less than 1% (55 out of 8113) of patients treated with Prolia for up to 5 years tested positive for binding antibodies (including pre-existing, transient, and developing antibodies). None of the patients tested positive for neutralizing antibodies, as was assessed using a chemiluminescent cell-based in vitro biological assay.”
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