Voyager's gene therapy for Parkinson's shows promise in early data from small Phase Ib trial
Voyager Therapeutics $VYGR reported some good news from the front lines of its gene therapy clinical trial in Parkinson’s, showing the company’s drug might one day rescue patients from the inevitable decline associated with their response to levodopa.
Parkinson’s, characterized by low dopamine levels in the brain, progresses over time with the patient experiencing a debilitating loss of motor and non-motor functions – with symptoms like trembling, slowing of movements, and impaired balance. As the disease progresses, these symptoms become more severe, resulting in periods of decreased function in the patient, also called “off” time. Thanks to excessive doses of levodopa aimed at treating the “off” time, some patients experience involuntary movements, or dyskinesia.
Voyager’s therapy, called VY-AADC, is currently in a Phase Ib trial that only includes 15 total patients, with 5 in each cohort. In its best-performing cohort, VY-AADC showed a mean increase of five hours a day of “on” time — without any dyskinesia — in Parkinson’s patients. The early data have Voyager upbeat, as it helped the company narrow down the dose that will be used in Phase II and III programs.
“Given the improvements in motor function and wider spectrum to titrate oral levodopa with our Cohort 2 dose, we are excited to consider this as our likely dose in the pivotal program while still planning to review the six-month results from the Phase 1 posterior trajectory trial next quarter,” said Bernard Ravina, chief medical officer of Voyager Therapeutics, in a statement. “We look forward to reviewing these results from the Phase 1b with the FDA as part of a planned Type C meeting and we continue to expect to dose the first patient in the pivotal Phase 2-3 program in mid-2018.”
The Cambridge, MA-based biotech reported a 2.1-hour improvement in “on” time from baseline to three years for patients in Cohort 1, a 3.5-hour improvement from baseline to 18 months in Cohort 2, and an improvement from baseline to six months of 1.5 hours that plateaued from six to 12 months in Cohort 3.