Kv7.2 Channel Activators

In many cases, KCNQ2-DEE is caused by reduced Kv7.2 potassium channel activity. Because of this, therapeutics that boost the activity of these channels are likely to be an effective treatment approach. Support for this comes from research showing that a Kv7.2 channel opener, retigabine (also called ezogabine), reduced seizures and improved alertness, motor skills, and vocalizations in some people with KCNQ2-DEE. Unfortunately, retigabine was taken off the market in 2017 due to unintended side effects, such as skin discoloration.

Other companies are still working on Kv7.2 channel activators, reworking the formula to maximize benefits while reducing side effects. This includes Biohaven’s experimental drug called BHVN-7000. They have already completed Phase 1 clinical trials showing that the drug is well-tolerated and safe in healthy volunteers, and are now testing how well it reduces seizures in adults with focal and generalized epilepsies in advanced stage clinical trials (Phase 3). Given the success of previous Kv7.2 targeting drugs and the established safety profile of BHVN-7000, the foundation has been closely following the development of the drug and wanted to let the community know about a potential opportunity to access the medication. 

FDA’s Expanded Access (Compassionate Use) Program

In some cases, people who are not eligible to join clinical trials and are not responding to available treatments can get access to investigational drugs through the FDA’s Expanded Access (or Compassionate Use) Program. Biohaven has recently supported expanded access for one individual with KCNQ2-DEE, and the initial outcomes were reported at the American Epilepsy Society meeting. Treatment with BHVN-7000 allowed the patient to wean off a previous version of a potassium channel activator, which was being discontinued. Other attempts to wean the individual off the older drug had been unsuccessful, so this was a very positive outcome for the family.

If you feel your loved one’s symptoms are not currently well managed and that they might benefit from access to an investigational potassium channel activator, start by discussing the opportunity with your physician. You can share the references in this blog post. Have your physician reach out to Jason Learner, MD (jason.lerner@biohavenpharma.com) at Biohaven for more information and guidance on next steps.