No systemic toxicity at ~1-2x AUC and 1-4x Cmax at the MRHD (rat, monkey); local nasal toxicity at all doses
“Etripamil was well tolerated in nonclinical studies following intranasal administration at exposures approximately 1- to 4- fold Cmax and 1- to 2- fold AUC at the MRHD.”
No significant systemic toxicity up to highest doses in 6-month monkey and 14-day rat; local nasal toxicity at all doses
“In the 6-month monkey and 14-day rat studies, there were no significant systemic toxicities observed up to the highest doses tested. However, local nasal toxicity at the site of administration was noted at all doses in both species.”