Edward M. Kaye

Eteplirsen for the treatment of Duchenne muscular dystrophy

In prior open‐label studies, eteplirsen, a phosphorodiamidate morpholino oligomer, enabled dystrophin production in Duchenne muscular dystrophy (DMD) with genetic mutations amenable to skipping exon 51. The present study used a double‐blind placebo‐controlled protocol to test eteplirsens ability to induce dystrophin production and improve distance walked on the 6‐minute walk test (6MWT).

A controlled trial of diazepam administered during febrile illnesses to prevent recurrence of febrile seizures

Background Phenobarbital, once widely prescribed to prevent febrile seizures, is now in disfavor because of its side effects and lack of efficacy. Diazepam, administered only during episodes of fever, may be a safe, effective agent to prevent the recurrence of febrile seizures. Methods We conducted a randomized, double-blind, placebo-controlled trial among 406 children (mean age, 24 months) who had at least one febrile seizure. Diazepam (0.33 mg per kilogram of body weight) or placebo was administered orally every eight hours during all febrile illnesses. Results During a mean follow-up of 1.9 years (a period during which 90 percent of febrile seizures recur), our intention-to-treat analysis showed a reduction of 44 percent in the risk of febrile seizures per person-year with diazepam (relative risk = 0.56; 95 percent confidence interval, 0.38 to 0.81; P = 0.002). A survival analysis of the length of time to the first recurrent febrile seizure did not show a significant difference between the treatment gr...

Longitudinal effect of eteplirsen versus historical control on ambulation in Duchenne muscular dystrophy

To continue evaluation of the long‐term efficacy and safety of eteplirsen, a phosphorodiamidate morpholino oligomer designed to skip DMD exon 51 in patients with Duchenne muscular dystrophy (DMD). Three‐year progression of eteplirsen‐treated patients was compared to matched historical controls (HC).

Longitudinal effect of eteplirsen vs. historical control on ambulation in DMD

To continue evaluation of the long‐term efficacy and safety of eteplirsen, a phosphorodiamidate morpholino oligomer designed to skip DMD exon 51 in patients with Duchenne muscular dystrophy (DMD). Three‐year progression of eteplirsen‐treated patients was compared to matched historical controls (HC).

Update on genetic disorders affecting white matter

The classification of diseases affecting white matter has changed dramatically with the use of magnetic resonance imaging. Classical leukodystrophies, such as metachromatic leukodystrophy and Krabbes disease, account for only a small number of inherited diseases that affect white matter. Magnetic resonance imaging has clarified genetic disorders that result in white matter changes or leukoencephalopathies. The term leukoencephalopathy is used to reflect the broader number of diseases that may cause as either primary or secondary changes in myelin development. This review attempts to categorize white matter disorders into classes such as lipid, myelin protein, organic acids, and defects in energy metabolism, in addition to other causes.

Safety and Pharmacokinetic Profiles of Phosphorodiamidate Morpholino Oligomers with Activity against Ebola Virus and Marburg Virus: Results of Two Single-Ascending-Dose Studies

ABSTRACT Two identical single-ascending-dose studies evaluated the safety and pharmacokinetics (PK) of AVI-6002 and AVI-6003, two experimental combinations of phosphorodiamidate morpholino oligomers with positive charges (PMOplus) that target viral mRNA encoding Ebola virus and Marburg virus proteins, respectively. Both AVI-6002 and AVI-6003 were found to suppress disease in virus-infected nonhuman primates in previous studies. AVI-6002 (a combination of AVI-7537 and AVI-7539) or AVI-6003 (a combination of AVI-7287 and AVI-7288) were administered as sequential intravenous (i.v.) infusions of a 1:1 fixed dose ratio of the two subcomponents. In each study, 30 healthy male and female subjects between 18 and 50 years of age were enrolled in six-dose escalation cohorts of five subjects each and received a single i.v. infusion of active study drug (0.005, 0.05, 0.5, 1.5, 3, and 4.5 mg/kg per component) or placebo in a 4:1 ratio. Both AVI-6002 and AVI-6003 were safe and well tolerated at the doses studied. A maximum tolerated dose was not observed in either study. The four chemically similar PMOplus components exhibited generally similar PK profiles. The mean peak plasma concentration and area under the concentration-time curve values of the four components exhibited dose-proportional PK. The estimated plasma half-life of all four components was 2 to 5 h. The safety of the two combinations and the PK of the four components were similar, regardless of the target RNA sequence.

Dysmyelinogenesis in animal model of GM1 gangliosidosis

Magnetic resonance imaging (MRI), pathologic examinations, and biochemical analyses were performed on 2 different canine mutants with GM1 gangliosidosis (i.e., English Springer Spaniel and Portuguese Water Dog) and on age- and sex-matched controls. Serial MRI studies were also performed on a child with infantile-onset GM1 gangliosidosis. The affected dogs had abnormalities on MRI, including a relative increase in gray matter and an abnormal signal intensity of cerebral and cerebellar white matter observed on T2-weighted MRI. White matter changes on MRI were similar to white matter abnormalities observed in a 15-month-old boy with GM1 gangliosidosis. The weight ratio of white to gray matter from the frontal lobe was markedly reduced. Microscopic examination revealed characteristic ballooned neurons which stained lightly with Luxol-fast blue. The central cerebral and cerebellar folia white matter exhibited pallor and gliosis, while the corpus callosum and fornix stained normally with Luxol-fast blue. Axons appeared intact on Bodian staining. Ultrastructural studies revealed fewer myelinated axons in affected puppies. Total gangliosides in gray matter were elevated. Thin-layer chromatography demonstrated GM1 ganglioside as the predominant ganglioside. The amount of cerebrosides and sulfatides was reduced in the gray and white matter when compared to controls but the ratio in gray and white matter remained unchanged. Immunostaining of neutral glycolipids disclosed increased amounts of stage-specific embryonic antigen-1 glycolipid in gray matter. These findings suggest that canine models for GM1 gangliosidosis are associated with abnormal myelin development which may be similar to the human disease.

Neonatal herpes simplex meningoencephalitis associated with fetal monitor scalp electrodes

Two full-term unrelated infants developed herpetic lesions at the site of scalp fetal monitor electrodes several days after uncomplicated labor and vaginal delivery. The mothers had been asymptomatic during pregnancy. In addition to the scalp vesicles, one infant had unilateral herpetic conjunctivitis; the other infant had vesicles on the face without ocular involvement. Both babies had cerebro-spinal fluid (CSF) pleocytosis and elevated protein. Herpes virus was cultured from the vesicles and CSF. Computed tomography showed low density areas in the frontotemporal regions. On follow-up, seizures persisted and neurologic development was impaired. These patients illustrate the potential risk of infection when internal fetal monitoring is used in low risk pregnancies.

Acetazolamide and furosemide for posthemorrhagic hydrocephalus of the newborn

The authors evaluated the efficacy of acetazolamide (ACZ) and furosemide (FUR) in avoiding ventricular shunting procedures in preterm infants with posthemorrhagic hydrocephalus (PHH) and increased intracranial pressure (ICP). Preterm infants were screened for PHH (defined as ventriculomegaly [VM] and increased ICP measured with the Ladd fiberoptic monitor). PHH infants were randomized to ACZ and FUR treatment or serial lumbar puncture (LP) and monitored until not receiving medications or having undergone shunting. Of 69 infants with IVH screened for the study, 39 never developed VM, 14 developed VM, without increased ICP, and 16 developed PHH. Ten PHH infants were randomized to ACZ and FUR treatment and six to serial LP. Nine (90%) of the 10 infants assigned to the ACZ and FUR group avoided shunting. Nephrocalcinosis developed in a significant proportion of treated infants. Three (50%) of the six LP group infants did not require shunting procedures (P = 0.118). The authors conclude that ACZ and FUR therapy is useful in the treatment of preterm infants with PHH. Because a significant number of infants treated with both ACZ and FUR developed nephrocalcinosis, close monitoring for increased calcium excretion in the urine, or use of ACZ without FUR, is advised.

Electron Microscopic Examination of Skin Biopsy as a Cost-Effective Tool in the Diagnosis of Lysosomal Storage Diseases:

In this report, we have summarized our 9-year experience of over 100 proven cases of lysosomal storage disease using electron microscopic evaluation of skin biopsies as a screening tool. The skin biopsy was very specific in establishing the diagnosis in only two disorders, namely neuronal ceroid lipofuscinosis and mucolipidosis IV. Although the biopsy was not diagnostic in other categories of storage diseases, it proved to be highly sensitive and provided valuable clues to direct further investigations on the basis of morphologic appearance of stored material and the cell type affected. Only in two cases of biochemically proven lysosomal storage disease was the morphologic diagnosis unable to be confirmed. We have compared the cost of screening for storage disorders using skin biopsy with the cost of performing multiple lysosomal enzyme assays. Our findings indicate that the skin biopsy, although more expensive than a single enzyme assay, provides an efficient, rapid, cost-effective tool to screen for more than 35 lysosomal storage disorders. (J Child Neurol 1996;11:301-308).