Viral vectors for treating neurogenic detrusor overactivity

A herpes simplex virus 1 (HSV-1) viral expression vector comprising at least:

• a) one promoter active selectively in afferent neurons of the bladder, wherein said promoter active selectively in afferent neurons of the bladder is a promoter of Calcitonin Gene Related Peptide (CGRP);
• b) at least one transcription cassette comprising a nucleotide sequence operably linked to said promoter,
• wherein said nucleotide sequence prevents the neurotransmitter filled synaptic vesicles from attaching to the presynaptic membrane, therefore inhibiting exocytosis of the neurotransmitter from the presynaptic nerve terminal, and
• wherein said nucleotide sequence codes for a wild-type or a modified bacterial neurotoxin light chain of Clostridium tetani or botulinum or for an active fragment thereof disrupting the SNARE complex or an active fragment thereof;
• and
• c) one sequence conferring long-term expression, wherein said long-term expression sequence is an LTE and a DNA insulator from the HSV-1 genome and wherein said transcription cassette is placed between the LTE and the DNA insulator.