Long-term constitutive expression of Epo in AAV-transduced primates. (A) Transduction with AAV-CMV-Epo (primate RQ1582). (B) Transduction with AAV-RSV-Epo (primate 97E026). Times following administration of vector are indicated. Serum Epo levels (•) and hematocrit levels (⋄) were measured.