Immusoft Corp., of Seattle, said it has made the final closing in its $20 million oversubscribed series B financing. The proceeds will be used to advance ISP-001 (iduronicrin genleukocel-T) through phase I/II development. ISP-001 incorporates Immusoft's Sleeping Beauty transposon engineered autologous B cells for the expression and delivery of alpha-L-iduronidase to treat mucopolysaccharidosis type I. The funds will also be used to support the development of additional pipeline candidates.