Conducted; negative (Ames, in vitro micronucleus, in vivo mouse micronucleus)
“In genetic toxicity studies, imetelstat was not mutagenic in the in vitro bacterial reverse mutation assay.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Carcinogenicity
Not conducted pre-approval; mouse and rat carcinogenicity studies required as PMRs
“To address the carcinogenicity risk assessment of imetelstat, there will be separate Post Marketing Requirements (PMRs) for carcinogenicity assessments in the mouse and rat species.”
✓ 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
EFD in mice and rabbits: post-implantation loss/resorptions; no fertility or PPND studies
“Increased rates of post-implantation loss and early resorptions that resulted in a decreased number of viable fetuses and litter size per animal, and decreased uterine weight were observed at”
✓ VerifiedFDA multi-discipline review, p. 42Source ↗
Safety pharmacology
Stand-alone telemetered monkey CV/CNS/respiratory study plus ECG in 9-month monkey study; no effects
“There were no test article-related changes observed in the cardiovascular, central nervous or respiratory systems.”
✓ VerifiedFDA multi-discipline review, p. 41Source ↗
Genotox: Ames
Negative (bacterial reverse mutation)
“In genetic toxicity studies, imetelstat was not mutagenic in the in vitro bacterial reverse mutation assay.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Genotox: in vitro mammalian
In vitro micronucleus in human lymphocytes: negative
“The drug was also negative for clastogenicity in both the in vitro micronucleus assay in human lymphocyte cultures and the in vivo mouse bone marrow micronucleus assay.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Genotox: in vivo
Mouse bone marrow micronucleus: negative
“The drug was also negative for clastogenicity in both the in vitro micronucleus assay in human lymphocyte cultures and the in vivo mouse bone marrow micronucleus assay.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Carcinogenicity model
Not conducted pre-approval; mouse and rat studies to follow as PMRs
“To address the carcinogenicity risk assessment of imetelstat, there will be separate Post Marketing Requirements (PMRs) for carcinogenicity assessments in the mouse and rat species.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
Carcinogenicity timing
Not conducted before approval; mouse and rat carcinogenicity studies are postmarketing requirements
“To address the carcinogenicity risk assessment of imetelstat, there will be separate Post Marketing Requirements (PMRs) for carcinogenicity assessments in the mouse and rat species.”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗
hERG / QT
No hERG inhibition up to 750 µg/mL (~150 µM)
“Imetelstat did not inhibit hERG currents up to a concentration of 750 µg/ml (~150 µM).”