Solriamfetol for treating excessive daytime sleepiness caused by narcolepsy

1.1 Solriamfetol is recommended as an option for treating excessive daytime sleepiness in adults with narcolepsy with or without cataplexy. This is only if modafinil and either dexamfetamine or methylphenidate have not worked well enough or are not suitable.

1.2 This recommendation is not intended to affect treatment with solriamfetol that was started in the NHS before this guidance was published. People having treatment outside this recommendation may continue without change to the funding arrangements in place for them before this guidance was published, until they and their NHS clinician consider it appropriate to stop.

Why the committee made these recommendations

Excessive daytime sleepiness caused by narcolepsy is usually first treated with modafinil, then dexamfetamine or methylphenidate. Availability of other treatments such as sodium oxybate and pitolisant varies in clinics across England. If available, they're normally used after modafinil and dexamfetamine or methylphenidate.

Clinical trial evidence shows that solriamfetol reduces excessive daytime sleepiness compared with placebo. It does not show a difference in quality of life but this is not certain because of the way that quality of life was assessed in the trial. There is no data comparing solriamfetol with dexamfetamine or methylphenidate. And there is no direct data comparing it with sodium oxybate or pitolisant. There is some indirect data but it is from only a small number of short trials. So solriamfetol's clinical effectiveness compared with these treatments is uncertain.

The cost-effectiveness estimates for solriamfetol compared with dexamfetamine or methylphenidate are highly uncertain, because they were based only on assumptions. And they're likely to be higher than what NICE normally considers acceptable. But solriamfetol is cost effective compared with pitolisant and sodium oxybate. So solriamfetol is recommended if modafinil and dexamfetamine or methylphenidate have not worked well enough or are not suitable to control excessive daytime sleepiness caused by narcolepsy.