Anti-panitumumab antibodies (MAHA) in 9/10 low-dose, 2/10 mid-dose and 1/10 high-dose monkeys
“Nine of ten monkeys in the low dose group were MAHA positive (Monkey anti-human antibody defined as anti-panitumumab antibody); frequency for MAHA positive was 2/10 and 1/10 in the mid and high dose groups.”
No panitumumab binding in human or monkey cardiac tissue in formal tissue cross-reactivity studies
“Further, no binding of panitumumab was noted in human or monkey cardiac tissue in a formal tissue cross-reactivity studies which utilised optimised immunohistochemical techniques to assess specific panitumumab binding.”
Anti-panitumumab antibodies in 9/10 low-, 2/10 mid- and 1/10 high-dose monkeys; ADA-positive monkeys cleared drug faster
“Nine of ten monkeys in the low dose group were MAHA positive (Monkey anti-human antibody defined as anti-panitumumab antibody); frequency for MAHA positive was 2/10 and 1/10 in the mid and high dose groups. Monkeys that developed MAHA were noted to have more rapid elimination of panitumumab.”
Anti-panitumumab antibodies in 5.2% (74/1417); 18.9% of these neutralizing
“the incidence of anti-panitumumab antibodies was 5.2% (74/1417). Of the 74 patients who tested positive for anti-panitumumab antibodies, 18.9% (14/74) had neutralizing antibodies against panitumumab.”
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