Abstract: The present invention relates to a method of enhancing gene therapy by using an enzyme effective to degrade or digest and/or inhibit or reduce effector function of serum antibodies in the subject. More particularly, the subject is one that has no detectable antibodies that specifically bind to the gene therapy, or has either a low titre of neutralising antibodies (NAb) that specifically bind to the gene therapy or a low titre of total antibodies (TAb) that specifically bind to the gene therapy. The method may increase the serum half-life of the therapy and mean that a lower dose of the gene therapy can be administered than would otherwise be given.