On 18 May, NLS Pharmaceutics announced new data confirming that its narcolepsy product, a controlled release (CR) formulation of mazindol, has agonist activity at orexin-2 receptors (OX2Rs). The data came from a pre-clinical study that investigated the psychostimulant effects of mazindol in wild-type mice and OX2R knock-out mice. The OX2R knock-out mice were 70% less sensitive to mazindol than the wild-type mice, confirming the treatment’s OX2R agonist activity.
Narcolepsy is a chronic sleep disorder characterised by two major symptoms, namely excessive daytime sleepiness (EDS) and cataplexy (sudden loss of muscle control). It is caused by a deficiency of orexin, a neuropeptide that is essential in regulating sleep and arousal states. Narcolepsy is currently treated with stimulants, selective serotonin reuptake inhibitors (SSRIs) and other antidepressants, but these therapeutics only provide symptomatic treatment. As such, disease-modifying or curative drugs for the treatment of narcolepsy remain an important unmet need. Mazindol CR has the potential to become the first available treatment for narcolepsy that targets the cause of the disease through agonist activity at the OX2R.
While mazindol is a monoamine reuptake inhibitor like many of the other stimulants used to treat narcolepsy, its additional OX2R agonist activity could give it a competitive edge in the market. It will, however, need to demonstrate strong efficacy in Phase III trials if it is to be competitive, as there are several factors that could limit its uptake. Not only is mazindol a scheduled IV controlled substance, which will restrict its use, but it has been linked with several safety concerns. Some key opinion leaders previously interviewed by GlobalData indicated a reluctance to prescribe an immediate-release formulation of mazindol, which was previously prescribed off-label to treat narcolepsy, due to safety concerns regarding the sympathetic activity of mazindol as well as cardiac problems.
If NLS Pharmaceutics is successful in launching mazindol CR, it will face significant competition from several recently approved products, including Jazz Pharmaceuticals’ Sunosi (solriamfetol hydrochloride). Sunosi has experienced good uptake since its approval in the US in 2019 and the EU last year as the most effective treatment available for improving EDS, a particularly challenging aspect of narcolepsy treatment. GlobalData forecasts that Sunosi will have global sales just shy of $300m by 2027. Sunosi has showed no evidence of efficacy in cataplexy, however, so opportunities remain in the narcolepsy market for safer therapies that are effective for treating both EDS and cataplexy.