Unadjuvanted pandemic H1N1 influenza vaccine in HIV-1-infected adults

Abstract

We evaluated the immune response to a 2009 influenza A (H1N1) unadjuvanted vaccine in HIV-infected patients and assessed the boosting effect of a second dose. HIV-infected adults were enrolled and scheduled to receive the H1N1 unadjuvanted vaccine containing 15 μg of A/California/7/2009 haemagglutinin. Anti-H1N1 antibody titers were measured at enrollment and 4–8 weeks after each vaccination by using hemagglutination inhibition (HI) and virus neutralization (NT) assays. One hundred and four patients were analyzed. Seroconversion, as measured by using HI and NT assays, was observed in 52 (50.0%) patients and 49 (47.1%) patients, respectively, after the first dose. Seroconversion rate evaluated by using NT, but not HI, antibody titers was associated with HIV RNA levels of < 400 copies/ml (odds ratio, 3.21; 95% CI, 1.15–8.96). Other parameters, including CD4 cell count, were not associated with seroconversion. In a cohort that received two vaccine doses at a 4–8-week interval (n = 54), the seroconversion rate and geometric mean titer for HI antibodies were 44.4% (95% CI, 30.8–58.1%) and 30.5 (95% CI, 19.9–46.9) after the first dose, respectively, and 48.1% (95% CI, 34.4–61.9%) and 39.0 (95% CI, 26.1–58.2) after the second dose, respectively. Among HIV-infected patients, the seroconversion rate was around 50% after the first dose of unadjuvanted vaccine. A second dose of vaccine had a limited boosting effect on immunity in this patient cohort.

Higher Memory Responses in HIV-Infected and Kidney Transplanted Patients than in Healthy Subjects following Priming with the Pandemic Vaccine

“…Immunosuppressed patients have a general trend toward impaired antibody responses to non-adjuvanted vaccines [6] . Short-term antibody responses were indeed lower following 1 or 2 doses of non-adjuvanted influenza A/09/H1N1 vaccines in HIV-infected [12] , [13] and solid organ transplant (SOT) patients [13] – [15] . The extent to which adjuvanted vaccines may improve responses is thus of central interest.…”

Immune response to 2009 H1N1 vaccine in HIV-infected adults in Northern Thailand

“…However, the vaccine types used in those studies were different, for instances, inactivated Vero-cell-derived whole virion vaccine by Lagler et al 7 and other non-adjuvanted recombinant vaccines produced by several pharmaceutical companies. [8][9][10][11][12][13][14][15] Therefore, comparison of differences in immunogenicity among those vaccine including that used in our study may not be possible. Nonetheless, high seroconversion rates in HIV uninfected group indicated that the immunogenicity of the vaccines employed in those studies were adequate.…”

“…[2][3][4][5][6] However, several studies have shown poorer immune responses to the 2009 H1N1 vaccines in HIV-infected individuals. [7][8][9][10][11][12][13][14]16,17,[19][20][21] There are limited data in the HIV-infected population in resource-limited countries. We, therefore, evaluated the seroconversion and seroprotection rate to a 2009 H1N1 vaccine (Panenza ® ) in HIV-infected and healthy individuals in Thailand.…”

British HIV Association Guidelines on the Use of Vaccines in HIV‐Positive Adults 2015

“…One other study comparing HIV‐positive and HIV‐negative individuals suggested merely quantitative differences in the vaccine responses, thus offering a rationale for boosting strategies in the HIV‐positive population . In HIV‐positive adults however, administering higher/more frequent doses of standard non‐adjuvanted vaccine preparations has not been consistently associated with improved immunogenicity, whilst enhanced responses have been observed with novel adjuvanted preparations . Data on the clinical efficacy of influenza vaccination in HIV‐positive adults are limited.…”

“…Inactivated influenza vaccines are safe and well tolerated in HIV‐positive individuals . Injection site reactions are the most frequent side effects.…”