Male CD-1 mouse and male cynomolgus monkey (plus juvenile male mouse)
“Repeat-dose studies in adult male CD1 mice, and single and repeat-dose studies in adult male cynomolgus monkeys were conducted to evaluate the general toxicology of vitolarsen.”
✓ VerifiedFDA pharmacology/toxicology review, p. 47Source ↗
Why that species
Exon 53 skipping shown in monkey; not pharmacologically active in rodents (mouse used for general/juvenile tox)
“In vivo assessment of exon 53 skipping was included in the 12- and 39-week toxicity studies in monkey; viltolarsen is not pharmacologically active in rodents.”
✓ VerifiedFDA pharmacology/toxicology review, p. 3Source ↗
Surrogate molecule
No surrogate in tox; mouse-specific PMO (NDK-73) used only for mdx52 proof-of-concept
“In male mdx52 mice, IV administration of a mouse surrogate (NDK-73) as well as an additional morpholine oligonucleotide (NDK-33), which targets the Exon 53 3’ end of the mouse dystrophin gene”
✓ VerifiedFDA pharmacology/toxicology review, p. 46Source ↗