Increased total sleep time in normal mice and rats (ED50 1 and 4.4 mg/kg)
“Oral administration of lemborexant to mice and rats significantly increased total sleep time, without an effect on the REM sleep ratio, with an ED50 of 1 mg/kg and 4.4 mg/kg, respectively.”
✓ VerifiedFDA multi-discipline review, p. 46Source ↗
Why that model
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.
Reviewer's view of the efficacy data
Lack of effect in orexin-deficient knockout/transgenic mice shows sleep promotion acts via orexin signaling
“Oral doses up to 30 mg/kg to preproorexin knockout mice, in which the orexin pathway is dysfunctional, and to orexin neuron-deficient transgenic mice, did not induce sleep, demonstrating that lemborexant acts through the orexin signaling pathway to exert its sleep-promoting effects in mice.”
✓ VerifiedFDA multi-discipline review, p. 46Source ↗