The experimental drug Zenvia, developed by Avanir Pharmaceuticals as a treatment for unwanted laughing/crying spells in ALS, has shown continued promise in lessening the frequency of such episodes in people with amyotrophic lateral sclerosis (ALS).
The results were seen in an extension to the company's phase 3 clinical trial, which concluded last fall. Avanir presented its results April 13 at the 2010 meeting of the American Academy of Neurology (AAN), held in Toronto.
Designed to treat pseudobulbar affect (PBA) — uncontrollable episodes of laughing or crying caused by neurological abnormalities — Zenvia is a combination of two existing medications, dextromethorphan and quinidine. (The drug formerly was called Neurodex.)
In fall 2009, Avanir announced encouraging results for its phase 3 trial of Zenvia in people with ALS or multiple sclerosis (MS). (See Zenvia shows promise in treating ALS-related emotional symptoms).
About the phase 3 Zenvia trial
In the phase 3 trial, approximately 300 participants with PBA secondary to either ALS or MS were randomly assigned to receive Zenvia capsules containing 30 milligrams of dextromethorphan and 10 milligrams of quinidine; Zenvia capsules containing 20 milligrams of dextromethorphan and 10 milligrams of quinidine; or placebo capsules. All participants took the capsules orally twice a day for 12 weeks.
At the end of the 12-week, placebo-controlled trial, the investigators found both Zenvia dosages significantly reduced the number of laughing and/or crying episodes compared to the placebo, and that the drug was generally safe and well tolerated.
About the open-label extension trial
The results announced April 13 at the AAN meeting are from a 12-week, open-label extension trial of Zenvia.
In this study, people with ALS or MS who had participated in the phase 3 trial were invited to take the 30-milligram dextromethorphan formulation of Zenvia (the higher of the two dextromethorphan doses) on an open-label basis for an additional 12 weeks. In an open-label trial, participants and investigators know what everyone is taking.
The company said those taking Zenvia in the extension trial continued to benefit from the drug.
Meaning for people with ALS
According to information on the company's Web site, Avanir will move forward with its application to the U.S. Food and Drug Administration (FDA) seeking market approval for Zenvia to treat PBA. It expects a decision from the FDA on this application in late 2010.
As unwanted episodes of laughing or crying can be highly embarrassing and upsetting for people with ALS and their families, a safe, effective treatment to control these would be welcome by many.