A novel gene transfer vector, NP2, is safe and well tolerated for the treatment of intractable pain, researchers reported in the April 11 online Annals of Neurology. Investigators conducted a multicenter, dose-escalation, phase I clinical trial of intradermal NP2 injection in 10 subjects with persistent pain caused by cancer, despite treatment with morphine or other analgesic. Participants who received the low dose of NP2 reported no substantive change in pain; patients in the middle and high dose cohorts reported pain relief. “There were no placebo controls in this relatively small study,” the authors concluded. “But the dose-responsive analgesic effects suggest that NP2 may be effective in reducing pain and warrants further clinical investigation.”
The FDA has approved DaTscan (ioflupane I 123 injection) for detecting dopamine transporters in the brains of adults with suspected Parkinsonian syndromes. The radiopharmaceutical agent is intended for use with single photon emission CT imaging to evaluate neurodegenerative movement disorders. The injection may be used as an adjunct to other diagnostic evaluation tools to distinguish between essential tremor and tremor due to Parkinson’s disease, as ioflupane I 123 injection alone cannot differentiate between different types of parkinsonian syndromes. The FDA’s approval was based on two phase III clinical trials in which the drug was used to evaluate dopamine transporter distribution in the brains of adult patients. As a new diagnostic adjunct to clinical assessments, ioflupane I 123 can potentially help physicians select the appropriate treatments for patients with movement disorders.
Persons who are regularly exposed to welding fumes may be at an increased risk for brain damage, specifically in the same areas affected by Parkinson’s disease, researchers reported in the April 12 Neurology. “Welding exposes workers to manganese fumes, but it is unclear if this exposure damages dopaminergic neurons,” the authors stated. “The purpose of this study [was] to determine whether welding exposure is associated with damage to nigrostriatal neurons.” Using PET imaging on 20 welders with no parkinsonian symptoms, 20 individuals with symptoms, and 20 healthy controls, the investigators determined that asymptomatic welders had higher manganese levels in the blood and an average 11.7% reduction in dopamine in certain brain regions. The pattern of reduction seen in welders, however, was distinct from the dysfunction pattern found in symptomatic Parkinson’s disease.
The FDA has approved Nuedexta (dextromethorphan hydrobromide and quinidine sulfate) for the treatment of pseudobulbar affect. The new therapy will help patients manage pseudobulbar affect that occurs secondary to multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), traumatic brain injury, stroke, Parkinson’s disease, and other neurologic diseases. Nuedexta combines dextromethorphan hydrobromide and quinidine sulfate, a metabolic inhibitor that enables therapeutic dextromethorphan concentrations. These components act on NMDA receptors and sigma-1 in the brain, but the mechanism by which it exerts therapeutic effects in patients with pseudobulbar affect is unknown. The drug was tested in patients with ALS and MS and reduced involuntary laughing and crying episodes compared with placebo.
Virtual reality may be an effective adjunctive therapy for patients experiencing upper arm motor deficits following stroke, according to a study published in the May Stroke. Researchers analyzed seven observational studies and five randomized trials that investigated the effects of virtual reality and video game technology on stroke patients’ upper arm strength and function. Among the observational studies, there was a 14.7% improvement in motor impairment and a 20.1% improvement in motor function; in the randomized trials, patients had an almost five times higher chance of improvement in motor function, compared with those who received traditional therapy. The researchers concluded, “Virtual reality and video game applications are novel and potentially useful technologies that can be combined with conventional rehabilitation for upper arm improvement after stroke.”
Investigators found that surgical revascularization can restore lost brain tissue in patients with cerebrovascular disease that impairs blood flow to the brain, as reported in the online April 14 Stroke. Twenty-nine patients who had undergone vascularization were included in the study. All patients had pre- and postsurgery studies of cerebrovascular reactivity using MRI, and cortical thickness in regions corresponding to steal physiology were measured. “At an average of 11 months after surgery, cortical thickness increased in every successfully revascularized hemisphere,” the authors stated. “Mean cortical thickness in the revascularized regions increased by 5.1%.” The investigators’ goal was to halt further loss of brain tissue due to strokes, “so it was remarkable to see the loss was actually reversed,” they commented.