Cyclosporin H is a selective and potent inhibitor of FPR-1 (formyl peptide receptor 1). Cyclosporin H, a viral transduction enhancer, increases lentiviral transduction up to 10-fold in human cord blood-derived hematopoietic stem and progenitor cells (HSPCs). Cyclosporin H displays an additive effect when combined with Rapamycin or Prostaglandin E2. Cyclosporin H lacks immunosuppressant activity of Cyclosporin A.