More Studies Required
The research, which prospectively collected data and blood samples from patients with HIV who received the JYNNEOS vaccine, is small and included only 24 patients with HIV infection, with seven hospital workers who also received the vaccine and seven unvaccinated individuals as controls. “I am one of the control subjects of the study, and intradermal vaccination is not especially pleasant,” said Dr. Güerri-Fernandez. “It is a very innervated area, and the moment of introducing the liquid is uncomfortable. But it is perfectly bearable.”
Outpatient HIV-infected patients from the Infectious Diseases Unit of Hospital del Mar on antiretroviral therapy and with undetectable viral loads were grouped according to their CD4+ T-lymphocyte counts. Those with CD4+ T-lymphocyte counts ≤ 500/mm3 required at least one booster vaccine to exhibit efficient virus-specific T-lymphocyte responses. The magnitude of the T-cell response after this booster correlated directly with the CD4+ T-lymphocyte count of those vaccinated.
For Argentine infectious disease specialist Julián García, MD, clinical researcher at the Huésped Foundation in Buenos Aires, Argentina, who did not participate in the study, it is always productive to know that T-cell responses develop in patients with HIV infection, with CD4+ T-lymphocyte counts > and < 500/mm3, through an intradermal administration route.
Dr. García emphasized that the most novel aspect is that the JYNNEOS vaccine induces a specific T-cell response in patients with HIV infection that increases with higher CD4+ T-lymphocyte levels. However, he noted that the number of patients was less than 10 in most study groups, and the control group had only intradermal administration, which limits the interpretation of the results. “It will be necessary to verify this in studies with larger groups with control groups from all routes and with a correlate of protection.”
Dr. García referred to this latter point as a significant source of uncertainty. “The study is fundamentally based on the cellular response, but nowadays, there is no immune correlate of real-life protection.” He concluded that the study builds knowledge, which is essential for a vaccine that began to be used for mpox and the effectiveness of which is based on estimates.
Dr. Güerri-Fernandez and Dr. Garcia declared no relevant financial conflicts of interest.
This story was translated from the Medscape Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.