13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility
Formal carcinogenicity studies have not been conducted with inotuzumab ozogamicin. In toxicity studies, rats were dosed weekly for 4 or 26 weeks with inotuzumab ozogamicin at doses up to 4.1 mg/m2 and 0.73 mg/m2, respectively. After 26 weeks of dosing, rats developed hepatocellular adenomas in the liver at 0.73 mg/m2 (approximately 2 times the exposure in patients at the maximum recommended dose, based on AUC).
Inotuzumab ozogamicin was clastogenic in vivo in the bone marrow of male mice that received single doses ≥ 1.1 mg/m2. This is consistent with the known induction of DNA breaks by calicheamicin. N-acetyl-gamma-calicheamicin dimethylhydrazide (the cytotoxic agent released from inotuzumab ozogamicin) was mutagenic in an in vitro bacterial reverse mutation (Ames) assay.
In a female fertility and early embryonic development study, female rats were administered daily intravenous doses of inotuzumab ozogamicin up to 0.11 mg/m2 for 2 weeks before mating through Day 7 of pregnancy. An increase in the proportion of resorptions and decrease in the number of viable embryos and gravid uterine weights were observed at the 0.11 mg/m2 dose level (approximately 2 times the exposure in patients at the maximum recommended dose, based on AUC). Additional findings in female reproductive organs occurred in repeat-dose toxicology studies and included decreased ovarian and uterine weights, and ovarian and uterine atrophy. Findings in male reproductive organs occurred in repeat-dose toxicology studies and included decreased testicular weights, testicular degeneration, hypospermia, and prostatic and seminal vesicle atrophy. Testicular degeneration and hypospermia were nonreversible following a 4-week nondosing period. In the chronic studies of 26-weeks duration, adverse effects on reproductive organs occurred at ≥ 0.07 mg/m2 in male rats and at 0.73 mg/m2 in female monkeys [see Use in Specific Populations (8.3)].