These cells are transduced ex vivo using a lentiviral vector encoding the human arylsulfatase A gene to insert a functional gene to produce the ARSA enzyme. When the modified cells are transplanted back into the patient as a one-time infusion, the cells have been shown to produce the missing ARSA enzyme. The children by the age of five were all in good condition and going to kindergarten when normally by this age, children with the disease can not even speak. Additional information can be found on the MLD Foundations Gene Therapy page and at the Clinical Trials.gov site. In November, 2020, Orchard Therapeutics acknowledged IND discussions with the FDA as the part of their effort to seek FDA approval in the USA. A trial for late juveniles was launched in February 2020. Orchard Therapeutics acquired the gene therapy IP from GSK in April 2018. Recruiting for the Phase I/II Clinical Trial formally started on March 24, 2010, after approval from the Italian Authorities. Recruiting the initial cohort of 8 patients was completed in mid-March 2013. The trial was to test the efficacy and safety of autologous (using the patients own cells) hematopoietic stem cell transplantation (HSCT) after genetic modification to deliver a super-therapeutic (over-expressing) ARSA enzyme to the nervous system by the route of the blood cells. Using the patients own stem cells with genetic correction should reduce or eliminate the complications of graft vs. host disease and provide a long-term solution to proper ARSA expression in MLD patients. Bench and animal tests showed positive results.
Heart valve dysplasia is a congenital heart defect which affects the aortic, pulmonary, mitral, and tricuspid heart valves. Dysplasia of the mitral and tricuspid valves can cause leakage of blood or stenosis.Dysplasia of the mitral and tricuspid valves - also known as the atrioventricular (AV) valves - can appear as thickened, shortened, or notched valves. The chordae tendinae can be fused or thickened. The papillary muscles can be enlarged or atrophied. The cause is unknown, but genetics play a large role. Dogs and cats with tricuspid valve dysplasia often also have an open foramen ovale, an atrial septal defect, or inflammation of the right atrial epicardium. In dogs, tricuspid valve dysplasia can be similar to Ebsteins anomaly in humans.Mitral valve stenosis is one of the most common congenital heart defects in cats. In dogs, it is most commonly found in Great Danes, German Shepherd Dogs, Bull Terriers, Golden Retrievers, Newfoundlands, and Mastiffs. Tricuspid valve dysplasia is most common in the Old English Sheepdog, German Shepherd Dog, Weimaraner, Labrador Retriever, Great Pyrenees, and sometimes the Papillon. It is inherited in the Labrador Retriever.The disease and symptoms are similar to progression of acquired valve disease in older dogs. Valve leakage leads to heart enlargement, arrhythmias, and congestive heart failure. Heart valve dysplasia can be tolerated for years or progress to heart failure in the first year of life. Diagnosis is with an echocardiogram. The prognosis is poor with significant heart enlargement. == References ==