Cevaretigene ritoparvovec (MeiraGTx)

MeiraGTx unveiled results from a small dataset for its Parkinson’s disease gene therapy on Tuesday morning, causing its shares $MGTX to jump by as much as 24%. In what the company called a “bridging study” featuring 14 patients, the high dose of MeiraGTx’s AAV-GAD showed a statistically significant improvement on a Parkinson’s disease measurement score known as MDS-UPDRS Part 3 after 26 weeks. Five patients in the high-dose group improved their “off” state scores by an average of 18 points from baseline, good for a p-value of 0.03. MeiraGTx CEO Alexandria Forbes said in a statement that the company expected a five- to 10-point improvement to represent a clinically meaningful change. The sham group (four patients) and low-dose group (five patients) saw no significant changes compared to baseline. The primary endpoint was safety and tolerability, and was met. In another exploratory endpoint, MeiraGTx said a quality-of-life measure called the PDQ-39, which uses a patient questionnaire, achieved statistical significance in both dosing groups when compared to patients’ baseline scores. There was only a “trend to significance” between the high-dose group and the sham group, MeiraGTx said. The company is still discussing its Phase 3 plans with regulators, but expects to launch a pivotal trial in the first half of 2025, according to a corporate slide deck updated Tuesday morning. Gene therapies for Parkinson’s disease have been attempted before, though none have been FDA-approved. MeiraGTx’s program is designed to reset the abnormal brain activity associated with the disease by targeting production of a brain chemical called gamma-aminobutyric acid, or GABA. AAV-GAD attempts to deliver a functional copy of a gene called GAD into the brain that would increase GABA production and alleviate motor symptoms.

A MeiraGTx Holdings gene therapy for Parkinson’s disease has preliminary data from a small clinical trial showing the one-time treatment showed both safety and efficacy, results that lay the groundwork for discussions with regulators about a Phase 3 study. The MeiraGTx gene therapy, AAV-GAD, had previously posted Phase 1 and Phase 2 results showing it was well tolerated with no significant adverse effects. The results announced Tuesday are from a Phase 1 bridging study designed to evaluate doses of AAV-GAD manufactured by London-based MeiraGTx at its own facilities using its commercial platform process. Parkinson’s patients lack sufficient amounts of a neurotransmitter called dopamine. Standard treatment includes the drug levodopa, a compound that a brain enzyme converts into dopamine. But dopamine replacement therapies lose efficacy over time. The motor symptoms of Parkinson’s can also be treated with deep brain stimulation, but that’s an invasive procedure. sponsored content Upcoming Webinar: Battle of the Budget: Employers vs. Rising Healthcare Costs Gain valuable knowledge and practical insights on how employers are addressing an increasingly complex healthcare budget landscape. By Personify Health MeiraGTx’s gene therapy is designed to spark local production of a neurotransmitter called GABA, which is intended to reprogram dysfunctional brain circuits and restore more normal activity to cells, alleviating motor symptoms. The 26-week bridging study enrolled Parkinson’s patients who had a history of responsiveness to levodopa treatment for at least 12 months. A total of 14 participants were randomly assigned to receive a high dose, a low dose, or a sham treatment. According to MeiraGTx, AAV-GAD met the main goal of safety and tolerability with no serious adverse events (SAEs) reported. Efficacy, an exploratory endpoint, was evaluated by measuring motor examination scores. The company said at week 26, results show a statistically significant 18-point average improvement from baseline according to a rating scale used to measure the severity and progression of Parkinson’s. By comparison, no significant change was observed in the low-dose group or the sham cohort. “With material made using our proprietary production process at commercial scale, we have demonstrated that AAV-GAD is safe at all doses studied, including a higher dose than previously tested,” MeiraGTx President and CEO Alexandria Forbes said in a prepared statement. “We have now treated a total of 58 patients in this development program in three independent multicenter clinical studies and have seen no SAEs related to AAV-GAD treatment.” Participants who completed the bridging study have the option of enrolling in a long-term follow-up study, which will monitor them for five years. Meanwhile, MeiraGTx said it plans to discuss the results with regulators in the U.S., Europe, and Japan as it looks ahead to pivotal testing of the gene therapy. presented by Sponsored Post The Promise of Value-Based Care and MedTech Innovation Monica Vajani, Executive Director for mHUB’s MedTech Accelerator, discusses how mHUB is helping innovators transition healthcare towards value-based care. By Monica Vajani - mHUB MeiraGTx isn’t the only company working to develop a one-time treatment for Parkinson’s. Bayer’s bemdaneprocel is made by engineering donor cells, turning them into dopamine-producing neurons. These cells are surgically transplanted into a patient’s brain where they are intended to replace a patient’s lost dopamine production. Last year, Bayer reported positive safety and efficacy data from bemdaneprocel’s Phase 1 test. Last month, Bayer reported these encouraging trends continued measured at 24 months. Aspen Neuroscience is also developing a Parkinson’s cell therapy. But unlike Bayer’s approach, Aspen’s ANPD001 is made from stem cells sourced from a patient’s own skin, offering the potential to avoid immunosuppressive drugs needed to prevent the body from rejecting the transplanted cells. Last month, Aspen announced it had completed dosing of the first cohort of a Phase 1/2a test of this cell therapy. Image: Dr_Microbe, Getty Images