The present invention relates to a gene therapy vector which is useful in the treatment or prevention of hypertrophic cardiomyopathy in a subject in need thereof. The gene therapy vector of the invention comprises a nucleic acid sequence encoding a cardiac sarcomeric protein and a cardiomyocyte-specific promoter which is operably linked to said nucleic acid sequence. The invention furthermore relates to a cell which comprises the gene therapy vector. Pharmaceutical compositions which comprise the gene therapy vector and/or a cell comprising said vector are also provided. In another aspect, the invention relates to a method for treating or preventing hypertrophic cardiomyopathy in a subject by introducing the gene therapy vector of the invention into a subject in need of treatment.
