Randomized controlled trial of pyridoxine for tardive dyskinesia
To date, the only effective medications to treat the symptoms associated with schizophrenia are the “antipsychotic” class of medications. Unfortunately, these medications have many possible side effects, including involuntary muscle movements known as tardive dyskinesia (TD). There is a small body of evidence, however, to suggest that pyridoxine (also known as Vitamin B6) may help alleviate the symptoms of TD; this study will build on that research, and test whether pyridoxine represents an effective treatment.
Fredrik Jarskog, M.D.
Need/Problem: Involuntary muscle movements can emerge after long-term treatment with antipsychotic medications. This condition is called tardive dyskinesia (TD) and there are few treatments available for this debilitating and stigmatizing condition.
Grant Summary: This project will test whether pyridoxine represents an effective treatment for tardive dyskinesia (TD).
Goals and Projected Outcomes: Measure involuntary muscle movements before and after 8 weeks of pyridoxine or placebo. The hypothesis is that pyridoxine will help reduce the frequency and severity of involuntary muscle movements in people who have developed TD from taking antipsychotic medications.
Grant Details: To date, the only effective medications to treat the symptoms associated with schizophrenia are the “antipsychotic” class of medications. Unfortunately, these medications have many possible side effects, including involuntary muscle movements known as tardive dyskinesia (TD). While lowering the dose of the antipsychotic or changing to a different antipsychotic can sometimes improve TD, this approach doesn’t always help. Only one medication, valbenazine, has been FDA-approved for the treatment of TD. Valbenazine can be helpful, but only about half of those who received valbenazine in studies showed good improvement, and at this time, valbenazine can be a challenge to get access to because of limitations on insurance coverage and high cost.
Pyridoxine (also known as Vitamin B6) was shown in two small studies to help improve the symptoms of TD. In one study, 15 people with TD received pyridoxine 400 mg per day for 4 weeks and their involuntary movements improved by an average of 66%. A second study used a much higher dose of pyridoxine and participants had a similar improvement in TD symptoms.
Given that pyridoxine at 400 mg per day showed initial evidence of being safe and effective, the primary goal of the current study is to replicate the first study in a larger group of people. 50 individuals with TD will receive 8 weeks of pyridoxine 400 mg per day or placebo. During the study, participants will also continue to take their usual medications. The severity of involuntary movements will be measured at regular intervals during the study. Efficacy will be based on change in the severity of involuntary movements over the course of 8 weeks. Blood tests will also be performed to help provide information on how pyridoxine may work. This study will provide important knowledge about whether pyridoxine is a safe and effective treatment for involuntary muscle movements associated with TD. If pyridoxine is found to be effective, then pyridoxine would represent an important and cost-effective alternative to currently available treatments for TD.