No immunosuppression in repeat-dose toxicity studies
“belzutifan does not show off-target activity, did not induce proliferative changes or potential endocrine/hormonal perturbations, or immunosuppression in repeat-dose toxicity studies”
Mainly excretory organs and GI tract in rats; no melanin binding
“Distribution studies showed distribution of belzutifan to mostly excretory organs and the GI tract in rats. No gender differences were observed and no melanin binding was evident.”
Embryo-fetal toxicity, warranting a boxed warning given chronic use in younger patients
“given the chronic use of belzutifan in a younger population than other targeted oncology drugs, the review team recommended the label contain a boxed warning for embryo-fetal toxicity.”
✓ VerifiedFDA multi-discipline review, p. 36Source ↗