Researchers found that PD-1-enhanced DNA vaccination can induce sustained virus-specific CD8+ T cell immunity in an AIDS monkey model. The vaccinated monkeys remained free of AIDS for six years and achieved virologic control without the need for combination antiretroviral therapy (cART), a treatment used to suppress viral replication in individuals living with human immunodeficiency virus (HIV). The study also found that polyfunctional and broadly reactive effector-memory virus-specific T cells were maintained in the protected experimental macaques for over six years. The findings provide supporting evidence that the PD-1-enhanced DNA vaccine strategy holds promise as a third-generation DNA vaccine for AIDS prevention and immunotherapy.