By Lois E. Krahn, MD, as told to Sarah Ludwig Rausch
I've been doing narcolepsy work for 25 years, and there has never been a time with as much activity on as many different fronts. For people who live with this disease, it’s incredibly exciting. I see this every day.
Sleep is challenging to understand because of its very nature. A person isn’t fully aware of their environment or their behavior when they’re asleep, so their ability to monitor themselves and describe what they're doing is limited. People with narcolepsy find themselves switching from wake to sleep and sleep to wake. They’re aware of what happens when they're awake, but when they‘re asleep, they aren't able to describe what they're thinking about or what they're experiencing.
So we have to rely on data questions, sleep studies, and other sources of information to understand the issues. Unlike other fields of medicine, such as psychiatry, where we rely on a patient to tell us what's going on, we need other sources to complement what the person with narcolepsy can tell us. I find it beneficial to be able to talk to family members or close friends who have observed people when they’re asleep and can tell us what happened. We also rely on other lab testing.
This has been a time of incredible activity in the treatment of narcolepsy. For a long period, we had a set of medications we would use to help people. Then in 2019, the FDA approved two new medications.
One was brand-new and had never been used anywhere. It’s called solriamfetol (Sunosi). The other has been used for some time in Europe and was approved for use in the United States. That one is called pitolisant (Wakix). They also approved older medicine called sodium oxybate (Xyrem) for use in children.
Plus there are studies underway to develop even more. A new form of oxybate salts (Xywav) that doesn't contain as much sodium was approved in 2020. There’s another form of sodium oxybate being tested that’s a once-a-night dose. Right now, you have to take it twice a night.
Getting Clarity on Causes
I think we have a better understanding of the causes of narcolepsy, too. For many people, it results from an autoimmune process -- the immune system attacks brain cells that produce a peptide, or compound, called hypocretin or orexin. There's an exciting research program looking at medicines that boost the activity of hypocretin/orexin in the brain. Those studies are only beginning, but they represent a brand-new possible treatment that may get to the underlying issues that people with narcolepsy have.
Another interesting development was quite recent. In the United States, there wasn't a way to measure hypocretin/orexin levels unless it was in a research lab. Now there’s a commercial laboratory, which happens to be affiliated with my institution, Mayo Medical Lab, that can measure hypocretin/orexin on spinal fluid samples that are sent to them. It used to take a long time to get results, but now it's something much more readily available to doctors, and therefore to people with narcolepsy.
Better Treatments, Faster Diagnosis
My experience with other diseases is the more treatment options that exist, the more people are encouraged that maybe there's something out there that can help. Rather than just getting by and struggling and maybe not paying much attention to their problems, they’re more likely to seek out help. A lot of people have narcolepsy and never get diagnosed and, therefore, never get treated.
My own personal hope is that more people with narcolepsy and their families will say, “You know, something doesn't seem quite right. Let's see if we can figure out if it's a problem and if there's a treatment for it,” rather than just live with it. Living with it may not be ideal, because if a person falls asleep while driving, that puts them and others at risk. Or they may not do well in school, or they may be having difficulty being an effective employee or parent.
As far as where the research is heading, I think that we're going to have more tools to treat people. Then we may determine that there are different subtypes of narcolepsy. Right now we know about two types: People who have a condition called cataplexy and those that don’t have cataplexy. I personally think there are probably other characteristics that will predict a person’s response to one treatment or another.
And then, as we create more treatments, we may be better able to help more people get relief from their symptoms. I hope we can somehow identify people at risk and come up with ways to intervene soon after onset. Their disease could be less severe because they won’t go as long without treatment.