CAMBRIDGE, MA, USA I December 10, 2018 I Voyager Therapeutics, Inc. (NASDAQ: VYGR), a clinical-stage gene therapy company focused on developing life-changing treatments for severe neurological diseases, today announced dosing of the first patient in RESTORE-1, a Phase 2, randomized, double-blind, placebo-controlled trial evaluating the safety and efficacy of VY-AADC for the treatment of Parkinson’s disease in patients with motor fluctuations that are refractory to medical management.

“Patients with Parkinson’s disease need new therapeutic options, especially as the disease progresses and there is less AADC enzyme in parts of the brain where it is needed to convert levodopa to dopamine,” said Mark Richardson, M.D., Ph.D., Associate Professor, Director of Epilepsy and Movement Disorders Surgery at the University of Pittsburgh Medical Center and principal investigator in the RESTORE-1 trial. “Voyager’s VY-AADC is an experimental gene therapy that is designed to deliver the AADC gene into brain cells where the enzyme can be produced to increase dopamine production. We are excited to contribute to this Phase 2, placebo-controlled trial of VY-AADC in patients with Parkinson’s disease.”

About the RESTORE-1 Phase 2 trial of VY-AADC for Parkinson’s Disease

The Phase 2 RESTORE-1 trial will enroll patients who have been diagnosed with Parkinson’s disease for at least four years, are not responding adequately to oral medications, and have at least three hours of OFF time during the day as measured by a validated self-reported patient diary. Patients who meet the eligibility criteria will be randomized (1:1) to one-time administration of VY-AADC (for a total dose of up to 2.5×1012 vector genomes) or placebo surgery. 

The primary endpoint of RESTORE-1 is ON time without troublesome dyskinesia, or good ON time, as measured by a self-reported patient diary at 12 months. Secondary endpoints include diary OFF time, other motor function and quality of life measures from the United Parkinson’s Disease Rating Scales (UPDRS-II,-III scores), the Parkinson’s Disease Questionnaire (PDQ-39), and patient’s global function as measured by the proportion of participants with improvement on the Clinical Global Impression (CGI) score. The trial will also measure non-motor symptoms from the Non-Motor Symptom Scale (NMSS), as well as safety. 

Biomarker data include measurements of the coverage of the specific region of the brain (putamen) targeted with VY-AADC and measurements of AADC enzyme expression and activity in the putamen measured by positron emission tomography (PET) using fluorodopa F-18. Changes in patients’ daily doses of oral levodopa and related medications will also be recorded.

For additional information regarding Voyager’s RESTORE-1 Phase 2 clinical trial with its gene therapy VY-AADC for the treatment of Parkinson’s disease, please use the following link or email Voyager at clinicaltrials@vygr.com“>clinicaltrials@vygr.com.

About Voyager’s VY-AADC Gene Therapy for Parkinson’s Disease

VY-AADC is an investigational gene therapy product designed to deliver the AADC gene directly into neurons of the putamen where dopamine receptors are located, bypassing the substantia nigra neurons and enabling the neurons of the putamen to produce the AADC enzyme to convert levodopa into dopamine. With this approach, VY-AADC has the potential to durably enhance the conversion of levodopa to dopamine and provide clinically meaningful improvements by restoring motor function in patients and improving symptoms following a single administration.

The FDA granted Regenerative Medicine Advanced Therapy (RMAT) designation for VY-AADC for the treatment of Parkinson’s disease in patients with motor fluctuations that are refractory to medical management. RMAT designation is an expedited program for the advancement and approval of regenerative medicine products, including gene therapy products. RMAT designation was granted based on clinical data from the Phase 1b trial with VY-AADC in patients with Parkinson’s disease. During this trial, one-time administrations of VY-AADC demonstrated robust and durable improvements in patients’ motor function along with substantial reductions in use of daily oral levodopa and other Parkinson’s disease medications. Infusions of VY-AADC have been well-tolerated in this trial with no vector-related serious adverse events reported to date.

About Parkinson’s Disease

Parkinson’s disease is a chronic, progressive and debilitating neurodegenerative disease that affects approximately 1,000,000 people in the U.S.1 and seven to 10 million people worldwide2. While the underlying cause of Parkinson’s disease in most patients is unknown, the motor symptoms of the disease arise from a loss of neurons in the midbrain that produce the neurotransmitter dopamine. Declining levels of dopamine and the enzyme needed to convert levodopa to dopamine in this region of the brain, the putamen, leads to the motor symptoms associated with Parkinson’s disease including tremors, slow movement or loss of movement, rigidity, and postural instability. Additional motor symptoms during the advanced stages of the disease include falling and difficulty with speech and swallowing, with patients often requiring the daily assistance of a caregiver. 

There are currently no therapies that effectively slow or reverse the progression of Parkinson’s disease. Levodopa remains the standard of care treatment, with its beneficial effects on symptom control having been discovered over 40 years ago3. Patients are generally well-controlled with oral levodopa in the early stages of the disease but become less responsive to treatment as the disease progresses. Patients experience longer periods of reduced mobility and stiffness termed OFF time, or the time when medication is no longer providing benefit, and shorter periods of ON time when their medication is effective.

The progressive motor symptoms of Parkinson’s disease are largely due to the death of dopamine neurons in the substantia nigra, a part of the midbrain that converts levodopa to dopamine, in a single step catalyzed by the enzyme AADC.  Neurons in the substantia nigra release dopamine into the putamen where the receptors for dopamine reside. In Parkinson’s disease, neurons in the substantia nigra degenerate and the enzyme AADC is markedly reduced in the putamen, which limits the brain’s ability to convert levodopa to dopamine4. The intrinsic neurons in the putamen, however, do not degenerate in Parkinson’s disease5,6.

About Voyager Therapeutics

Voyager Therapeutics is a clinical-stage gene therapy company focused on developing life-changing treatments for severe neurological diseases. Voyager is committed to advancing the field of AAV gene therapy through innovation and investment in vector engineering and optimization, manufacturing and dosing and delivery techniques. Voyager’s pipeline focuses on severe neurological diseases in need of effective new therapies, including Parkinson’s disease, a monogenic form of ALS called SOD1, Huntington’s disease, Friedreich’s ataxia, neurodegenerative diseases related to defective or excess aggregation of tau protein in the brain including Alzheimer’s disease and severe, chronic pain. Voyager has strategic collaborations with Sanofi Genzyme and AbbVie.  Founded by scientific and clinical leaders in the fields of AAV gene therapy, expressed RNA interference and neuroscience, Voyager Therapeutics is headquartered in Cambridge, Massachusetts.

SOURCE: Voyager Therapeutics