AAV9-mediated gene therapy for treating mucopolysaccharidosis type I

A therapeutic regimen useful for treatment of an alpha-L-iduronidase deficiency in a human patient, wherein the regimen comprises administering to a patient:

• (a) a recombinant adeno-associated virus (rAAV) having an AAV9 capsid and a nucleic acid comprising a sequence encoding human α-L-iduronidase (hIDUA) under control of regulatory sequences which direct expression thereof in the patient, wherein the hIDUA coding sequence has the nucleotide sequence of nucleotides 1 to 1962 of SEQ ID NO:
• 1 or a sequence at least 80% identical to nucleotides 1 to 1962 of SEQ ID NO:
• 1 which encodes a functional hIDUA, wherein the regulatory sequences comprise a cytomegalovirus immediate early (CMV IE) enhancer, a chicken beta-actin promoter, a chicken beta actin intron, and a rabbit beta globin polyadenylation (poly A) signal sequence,
• (b) at least a first immunosuppressive agent which is an intravenous corticosteroid;
• and
• (c) at least a second immunosuppressive agent which is an oral corticosteroid,
• wherein administration of at least one immunosuppressive agent begins prior to or on the same day as delivery of the rAAV;
• and
• wherein administration of at least one of the immunosuppressive agents continues for at least 8 weeks post-rAAV administration.