Data

Immunogenicity and Safety Data of PCV13 in HIV-infected Adults

A randomised clinical trial was performed to compare the immunologic response towards a combined immunisation strategy involving the use of PCV13 with PPSV23 (prime-boost vaccine group), as compared with PPSV23 alone, in HIV-infected adults. The prime-boost vaccine group achieved a ≥4-fold increase in GMT at Week 8 and a ≥2-fold increase in IgG GMC at 8 weeks. This study revealed that combining PCV13 with PPSV23 results in a higher magnitude of immune response in HIV-infected individuals at 8 weeks as compared with PPSV23 alone.¹

A study investigated the immunogenicity induced by combined PCV13 and PPSV23 vaccines in HIV-infected adults. It was observed that the use of PPSV23 12 months after PCV13 improves PCV13 immunogenicity and PPSV23 has a decreasing effect on PCV13-associated immunological memory. These findings are in line with different guidelines that recommend the use of PCV13, instead of PPSV23 in HIV-positive individuals.²

In an open-label study, 329 HIV-infected adults previously vaccinated with PPSV23 were assessed for safety and immune response to 3 doses of PCV13. PCV13 appeared well-tolerated and immunogenic in HIV-infected adults with CD4 counts ≥200 cells/mm.^3,4 A Phase 3, open-label, single-arm study evaluated the immunogenicity and safety of 3 PCV13 doses followed by 1 dose of PPSV23 at 1 month in vaccine-naive individuals. Among 301 individuals enrolled and vaccinated, 279 individuals completed the study. The study revealed that the PCV13 regimen elicited significant immune responses to all serotypes and was well-tolerated in these HIV-infected individuals. However, subsequent PPSV23 or PCV13 administration resulted in only modest increases in the antibody titres.⁵

A randomised clinical trial conducted in Brazil with 331 HIV-infected patients evaluated the safety and efficacy of PCVs in these patients, alone and combined. In this study, both PCV7 and PPSV23 were found to be immunogenic and well-tolerated in these patients, and the immunogenicity of PCV7 was higher than PPSV23. No benefits were observed in combining the 2 vaccines.⁶

Song et al compared the immunogenicity of PCV13 in HIV-infected patients with CD4 T-cell count <350 cells/μL, as compared with those with a higher CD4 T-cell count. Although PCV13 was well- tolerated in all HIV-infected patients irrespective of their immune status, it showed significantly lower immunogenicity among patients with CD4 T-cell count <350 cells/μL, as compared with those HIV-infected patients with a higher CD4 T-cell count. The findings of this study indicate that it would be important to assess the optimum timing of vaccination in HIV-infected patients for achieving sufficiently protective immunity. However, current guidelines recommend PCV13 use in HIV-infected patients irrespective of CD4 T-cell count.⁷ 

Another recent study explored the virological and immunological outcomes of HIV-1–positive patients after immunisation with PCV13. In this retrospective study conducted in individuals aged ≥50 years, it was observed that in first 6 months after PCV13 vaccination amongst patients on stable virological suppression, confirmed virological failures and viral blips were rarely found. These findings indicated that the PCV13 is well tolerated in HIV-1–positive patients with respect to immunological and virological outcomes.⁸

A prospective pilot study compared the long-term immunological response with PCV13 versus PPSV23 among HIV-infected adults. It was observed that both vaccines achieved a serologic response that was durable over the long term. However, after 5 years of vaccination, minor differences were observed between the immunogenicity of the 2 vaccines, whereby PCV13 was found to be better than PPSV23.⁹

A study assessed the antibody responses of PCV13 and/or PPSV23 in elderly HIV-infected adults, aged between 50 and 65 years. As compared with the recommended regimen of PCV13/PPSV23, PPSV23 alone demonstrated a clear immunological advantage in older HIV-infected individuals, and as compared with HIV-PCV13/PPSV23 controls, antibody responses to PCV13/PPSV23 were lower.¹⁰ A previous study by the group had reported that upon revaccination with PPSV23 in this group of older adults, PCV13 does not enhance cellular responses.¹¹

HIV, human immunodeficiency virus; CD4, cluster of differentiation 4; GMC, geometric mean concentration;
GMT, geometric mean titre; PCV7, 7-valent pneumococcal conjugate vaccine; PCV13, 13-valent pneumococcal conjugate vaccine; PPSV23, 23-valent pneumococcal polysaccharide vaccine.

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