13 NONCLINICAL TOXICOLOGY
13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility
Carcinogenesis
Long-term studies in animals have not been performed to evaluate the carcinogenic potential of propofol.
Mutagenesis
Propofol was not mutagenic in the in vitro bacterial reverse mutation assay (Ames test) using Salmonella typhimurium strains TA98, TA100, TA1535, TA1537 and TA1538. Propofol was not mutagenic in either the gene mutation/gene conversion test using Saccharomyces cerevisiae, or in vitro cytogenetic studies in Chinese hamsters. In the in vivo mouse micronucleus assay with Chinese Hamsters propofol administration did not produce chromosome aberrations.
Impairment of Fertility
Female Wistar rats were administered either 0, 10, or 15 mg/kg/day propofol intravenously from 2 weeks before pregnancy to day 7 of gestation did not show impaired fertility (0.65 and 1 times the human induction dose of 2.5 mg/kg based on body surface area). Male fertility in rats was not affected in a dominant lethal study at intravenous doses up to 15 mg/kg/day for 5 days.
13.2 Animal Toxicology and/or Pharmacology
Intra-arterial injection in animals did not induce local tissue effects. Intentional injection into subcutaneous or perivascular tissues of animals caused minimal tissue reaction.
Published studies in animals demonstrate that the use of anesthetic agents during the period of rapid brain growth or synaptogenesis results in widespread neuronal and oligodendrocyte cell loss in the developing brain and alterations in synaptic morphology and neurogenesis. Based on comparisons across species, the window of vulnerability to these changes is believed to correlate with exposures in the third trimester through the first several months of life, but may extend out to approximately 3 years of age in humans.
In primates, exposure to 3 hours of an anesthetic regimen that produced a light surgical plane of anesthesia did not increase neuronal cell loss, however, treatment regimens of 5 hours or longer increased neuronal cell loss. Data in rodents and in primates suggest that the neuronal and oligodendrocyte cell losses are associated with subtle but prolonged cognitive deficits in learning and memory. The clinical significance of these nonclinical findings is not known, and healthcare providers should balance the benefits of appropriate anesthesia in neonates and young children who require procedures against the potential risks suggested by the nonclinical data [see Warnings and Precautions (5.3), Pregnancy (8.1), and Pediatric Use (8.4)].