Painful diabetic peripheral neuropathy (DPN) can be effectively treated with hepatocyte growth factor gene therapy, according to results of a phase 2 clinical trial presented at the 140th Annual Meeting of the American Neurological Association (ANA).
“Diabetic peripheral neuropathy can cause debilitating pain with no effective treatment, and hepatocyte growth factor has potent neurotropic and angiogenic properties that make it an ideal candidate for treating DPN,” stated Senda Ajroud-Driss, MD, Northwestern University Feinberg School of Medicine, Chicago, Illinois, speaking here on September 28.
Dr. Ajroud-Driss and colleagues conducted a double-blind study involving 104 patients to evaluate the safety and efficacy of intramuscular injections of a plasmid (VM202) containing 2 human hepatocyte growth factor isoforms in patients with DPN.
Subjects were randomised to receive 8 mg (low dose) of VM202 per leg, 16 mg (high dose) of VM202 per leg, or placebo, via intramuscular injections in the calves, separated by 2 weeks.
Patients in the low-dose arm improved the most in all efficacy measures with a significant reduction in mean pain score at 3 months that continued at 6 months and 9 months.
No significant adverse effects were observed among the 96 patients who completed the study.
These findings suggest that non-viral gene therapy is safe, well tolerated, and effective in providing long-term relief from the symptoms of DPN, according to the investigators.
“We were surprised to see that the low dose was more effective than the high dose, even though the phase1, dose-finding study suggested the presence of a dose response,” commented Dr. Ajroud-Driss. “The second surprise was the duration of the effect; pain relief was significant at 6 months in responders,” she added.
Dr. Ajroud-Driss also stressed that the drug had a better side-effect profile when compared with currently available neuropathic pain medications. She cautioned, however, that this was a phase 2 study, “so we have to wait for the results of the pivotal study to determine whether this treatment is really effective in the treatment of painful diabetic neuropathy.”