Paxlovid: which tox species, and why?

“Pivotal repeat-dose toxicology studies were conducted in rats (2-week and 1-month durations) up to 1000 mg/kg/day and in monkeys (15-day and 1-month durations) up to 600 mg/kg/day.”

“The species used for the GLP compliant pivotal studies included rats and monkeys based on similar PK profile seen in these species compared to human. Furthermore, the pharmacological target of PF-07321332 is an exogenous entity (virus-specific protein) and therefore there are no pharmacologically relevant species.”

“Pivotal repeat-dose toxicology studies were conducted in rats (2-week and 1-month durations) up to 1000 mg/kg/day and in monkeys (15-day and 1-month durations) up to 600 mg/kg/day.”

“Pivotal repeat-dose toxicology studies were conducted in rats (2-week and 1-month durations) up to 1000 mg/kg/day and in monkeys (15-day and 1-month durations) up to 600 mg/kg/day.”

“Fertility and embryo-foetal development studies were evaluated in rats and rabbits with PF-07321332 (studies 21GR146, 21GR132 and 21GR126). Pre- and postnatal development was evaluated in rats (21GR149) based on the interim results.”

“No carcinogenicity studies have been performed. Considering that the duration of treatment is limited to 5 days, the absence of carcinogenicity studies is in-line with the recommendations of ICH S1A.”

“Furthermore, the pharmacological target of PF-07321332 is an exogenous entity (virus-specific protein) and therefore there are no pharmacologically relevant species.”