People with Chorea Can Switch from Xenazine To Austedo Safely, Phase 3 Clinical Trial Shows

Huntington’s patients who are taking Xenazine for the twitching condition known as chorea can switch without concern to the newly approved Austedo, according to Austedo’s maker, Teva Pharmaceutical Industries.

A Phase 3 clinical trial showed that the switch was safe and that Austedo (deutetrabenazine) did a better job of controlling chorea than Lundberg Pharmaceuticals‘ Xenazine (tetrabenazine), Teva said. Teva  company sponsored the research along with the Huntington Study Group.

The U.S. Federal Drug Administration approved Austedo tablets in March 2017 for chorea, a condition characterized by involuntary muscular movements that affects 90 percent of Huntington’s patients.

Teva published the results of the ARC-HD clinical trial in JAMA Neurology. The article was titled “Safety of Converting From Tetrabenazine to Deutetrabenazine for the Treatment of Chorea.”

“Chorea is a debilitating symptom of Huntington disease that can impact the safety, function and quality of life of many patients,” Dr. Michael Hayden, chief scientific officer at Teva, said in a press release. “We are pleased to share the ARC-HD study results to allow those physicians treating [Huntington’s disease] patients to increase their knowledge of AUSTEDO.”

The 37 Huntington’s patients in the open-label, single-arm trial received Xenazine three times a day for eight weeks or more before researchers switched them overnight to two doses of Austedo a day.

They started with a dose of Austedo that was half the Xenazine dose. After seven days, researchers adjusted patients’ Austedo dose weekly to achieve optimal control of their chorea.

The team used several yardsticks to measure Austero’s effectiveness, including the United Huntington’s Disease Rating Scale, Total Maximal Chorea Score, and Total Motor Score.

Austedo controlled chorea as well as Xenazine after the first week, researchers said. At eight weeks, it was doing a significantly better job of controlling the condition, they said.

The treatment was well-tolerated. There were few cases of adverse side effects causing patients to reduce their dose of Austedo or discontinue it.

Overall, the results showed that patients can switch from Xenazine to Austedo safely without loss of  control over their chorea, the researchers said.

“Human-based research is critical to evolving our understanding of [Huntington’s disease] and to providing more options and meaningful treatments,” said Dr. Samuel Frank, the study’s principal researcher. “It could not be done without the dedication of patients and their families who participate in clinical trials, for which we are extremely grateful.”