Rescue Medications: Past & Present
Prior to 1997, there was no way for non-medical personnel such as caregivers to provide rescue therapy for their loved ones. The only rescue therapy available had to be done intravenously at the hospital. When rectal diazepam gel, or Diastat, came on the market, caregivers could use it in the home as anti-seizure medication for seizure clusters. There are some other medications (such as lorazepam, diazepam) that can be dissolved in the mouth.
- The rectal diazepam gel (Diastat) takes a little bit of time for the drug to be absorbed through the skin and sent to the brain. Note that it still works quickly relative to other options. Diastat may stop a seizure within 15 minutes of administration.
- Some people (such as school personnel, bus drivers, ambulance drivers, or other caregivers in the community) may not be allowed to give Diastat or other rescue therapies due to state level regulations or policies.
- People who could benefit from rescue therapy (like adults and adolescents) may not want to use a rectal form due to privacy.
Future of Rescue Medicine
For these reasons, there has been considerable interest about other ways of giving medicines outside of the hospital. In the early 2000s, researchers began exploring nasal forms of medicines (primarily midazolam and diazepam) that can be squirted into the nose or given buccally, between the gum and the cheek. Both options at present are not approved by the U.S. Food and Drug Administration (FDA) and need to be produced in special pharmacies. The sprays are somewhat dilute, and each dose can require 6 sprays.
This year’s Antiepileptic Drug and Device Trials in Miami, Florida, highlighted innovations for anti-seizure rescue therapies for out of hospital use. Specifically, anti-seizure drugs are now being designed to work as easy-to-use intranasal sprays or auto-injectors, like an EpiPen. Both options would make it much easier for non-emergency personnel to use. Here are three companies that presented at the meeting to watch in the rescue medication arena.
- Midazolam Nasal Spray (USL261) by Proximegen Limited passed its pivotal Phase 3 clinical trial and is now under review by the FDA.
- Staccato Alprazolam (AZ-002) by Alexza Pharmaceuticals is formulated to be used in a special inhaler. This may allow it to act very quickly. It is currently in Phase 2b trials to bring the product to market. Dr. Jacqueline French, chief scientific officer at the Epilepsy Foundation, has been spearheading clinical trials for AZ-002.
- Diazepam Auto-Injector from Xeris Pharmaceuticals is planning to start Phase 1 clinical trials next year. The company won a New Therapy Commercialization grant from the Epilepsy Foundation in 2012 to design a product that would work like an Epi-Pen for seizures. In the past five years, they have worked on improving the formula to ensure that an intramuscular injection would work and be easy to use.
I am only highlighting the three that were presented at the conference. However, there are other rescue medication options being developed. For example, Neurelis is also developing an intranasal spray for diazepam and the Department of Defense is also looking at intramuscular midazolam administration as a countermeasure in soldiers and civilians exposed to nerve agents that cause seizures.
These new methods of delivery are exciting because they are faster acting and easy to use. As these rescue medications become available on the market, we can begin to look at other preventative ways to use them. For example, if someone has an aura, would they be able to use the rescue medication to prevent the rest of the seizure?
As the director of the Epilepsy Innovation Institute, I look forward to following the development of these products. If you are interested in the drugs and devices in clinical development, please look at our therapies pipeline report updated every quarter.
Interested in learning more about the pipeline? Join us at the Epilepsy Foundation Pipeline Conference in San Francisco in February 2018.