The Scientist discusses humanized mice used at Taconic Biosciences:
"In 1993, National Institutes of Health (NIH) researchers gave Eli Lilly's promising experimental hepatitis B drug fialuridine to 15 patients as part of a small Phase 2 trial. It did not go well. Five of the patients died; two more required emergency liver transplants.
Fialuridine had undergone toxicity testing in mice, rats, dogs, and even nonhuman primates with no apparent ill effects, so the disastrous trial outcome was shocking. Years later, research revealed that drug uptake occurred via a transporter expressed in human mitochondria but not in the mitochondria of mice. Researchers now hypothesize that fialuridine builds up to toxic levels within mitochondria of the human liver, leading to catastrophic damage." Read the complete article at: TheScientist.com
"In 1993, National Institutes of Health (NIH) researchers gave Eli Lilly's promising experimental hepatitis B drug fialuridine to 15 patients as part of a small Phase 2 trial. It did not go well. Five of the patients died; two more required emergency liver transplants. Fialuridine had undergone toxicity testing in mice, rats, dogs, and even nonhuman primates with no apparent ill effects, so the disastrous trial outcome was shocking. Years later, research revealed that drug uptake occurred via a transporter expressed in human mitochondria but not in the mitochondria of mice. Researchers now hypothesize that fialuridine builds up to toxic levels within mitochondria of the human liver, leading to catastrophic damage."