Negative in Ames, in vitro TK6 micronucleus and rat bone marrow micronucleus assays
“Pralsetinib was not mutagenic in an in vitro bacterial reverse mutation (Ames) assay or clastogenic in either the in vitro micronucleus assay in TK6 cells or the in vivo bone marrow micronucleus assay in rats.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Carcinogenicity
Not conducted (advanced cancer indication)
“The Applicant did not conduct carcinogenicity or fertility studies to support the currently proposed indication (NSCLC), and these studies are not needed to support a marketing application for a drug intended to treat patients with advanced cancer.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Instead of carcinogenicity
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Instead of genotoxicity
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
DRG histopathology
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Reproductive & developmental
Rat EFD: visceral and skeletal malformations from 5 mg/kg/day; 100% post-implantation loss at ≥20 mg/kg/day
“In the EFD study, multiple visceral and skeletal malformations were observed, as well as developmental variation, even from the lowest dose level of 5 mg/kg/day. 100% post implantation loss was seen at 20 mg/kg/day and above.”
No relevant hERG inhibition or QTc prolongation in monkeys; increased blood pressure with decreased heart rate in rats at ≥25 mg/kg
“Pralsetinib did not inhibit in vitro hERG potassium currents at relevant concentrations or induce QTc prolongation in the 13-week repeat-dose study in cynomolgus monkeys. Single oral administration of ≥25 mg/kg pralsetinib resulted in increased blood pressure with concomitant decreases in heart rate in male Sprague-Dawley rats.”
✓ VerifiedFDA multi-discipline review, p. 42Source ↗
Genotox: Ames
Negative (bacterial reverse mutation)
“Pralsetinib was not mutagenic in an in vitro bacterial reverse mutation (Ames) assay or clastogenic in either the in vitro micronucleus assay in TK6 cells or the in vivo bone marrow micronucleus assay in rats.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Genotox: in vitro mammalian
In vitro micronucleus in TK6 cells: negative
“Pralsetinib was not mutagenic in an in vitro bacterial reverse mutation (Ames) assay or clastogenic in either the in vitro micronucleus assay in TK6 cells or the in vivo bone marrow micronucleus assay in rats.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Genotox: in vivo
Rat bone marrow micronucleus: negative
“Pralsetinib was not mutagenic in an in vitro bacterial reverse mutation (Ames) assay or clastogenic in either the in vitro micronucleus assay in TK6 cells or the in vivo bone marrow micronucleus assay in rats.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Carcinogenicity model
Not conducted (advanced cancer)
“The Applicant did not conduct carcinogenicity or fertility studies to support the currently proposed indication (NSCLC), and these studies are not needed to support a marketing application for a drug intended to treat patients with advanced cancer.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Carcinogenicity timing
Not needed for the advanced cancer indication (ICH S9)
“FDA agrees that carcinogenicity studies are not needed to support the use of pralsetinib in the currently proposed indication per ICH S9.”
✓ VerifiedFDA multi-discipline review, p. 74Source ↗
“The IC50 value of 5.18 µM (n=2) determined in the non-GLP in vitro hERG channel study (Study #CPB-25-15-010A-0169) suggests minimal risk of QT prolongation through this pathway in humans given pralsetinib.”
✓ VerifiedFDA multi-discipline review, p. 51Source ↗
Not genotoxic overall: Ames negative; in vitro chromosome aberration positive without (not with) metabolic activation; rat micronucleus and comet negative