We report the case of a 32-year-old woman from São Paulo, Brazil, who was exposed to HIV but did not acquire the infection. This case demonstrates unique immune control characterized by transient viremia and the absence of seroconversion over a 10-year follow-up period. Genetic analysis revealed protective HLA alleles, a robust IFN-γ response to p24/Nef peptides, persistently high CD4+ T cell counts, and normal immune responses to other pathogens (e.g., Hepatitis A, CMV). These findings suggest that the inability to establish persistent HIV infection may be linked to the interaction of multiple factors, including a potent and sustained CD4+ T cell and cytotoxic response.