The present invention provides methods and compositions for improving efficacy of viral transduction of cells. More particularly, the present invention provides methods and materials useful for safely and reliably improving the efficiency of methods and materials useful for safely and reliably improving the efficiency of methods for transducing cells, such as human hematopoietic stem cells (HSC), with viruses and/or viral vectors. The compositions and methods are useful for therapeutic indications amenable to treatment with hematopoietic stem cell gene therapies.
