A 5-year longitudinal follow-up study of serological responses to 23-valent pneumococcal polysaccharide vaccination among patients with HIV infection who received highly active antiretroviral therapy

Bacterial Vaccinations in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a frequent, often progressive, chronic disease of the lungs. Patients with COPD often have impaired immunity; therefore, they are prone to chest infections, such as pneumonia or bronchitis. Acute exacerbations of COPD are major events that accelerate disease progression, contributing to its symptoms' burden, morbidity, and mortality. Both pneumonia and acute exacerbations in COPD are caused by bacteria against which there are effective vaccinations. Although the number of randomised controlled studies on bacterial vaccinations in COPD is limited, national and international guidelines endorse specific vaccinations in patients with COPD. This review will summarise the different types of vaccinations that prevent pneumonia and COPD exacerbations. We also discuss the results of early phase studies. We will mainly focus on Streptococcus pneumoniae, as this bacterium was predominantly investigated in COPD. However, we also review studies investigating vaccinations against Haemophilus influenzae, Moraxella catarrhalis, and Bordetella pertussis.

A Retrospective Study of the Safety and Immunogenicity of MVC-COV1901 Vaccine for People Living with HIV

BACKGROUND

This study aimed to assess the safety and immunogenicity of MVC-COV1901, a recombinant COVID-19 protein vaccine, containing S-2P protein adjuvanted with CpG 1018 and aluminum hydroxide, for people living with HIV (PWH).

METHODS

A total of 57 PWH of ≥20 years of age who are on stable antiretroviral therapy were compared with 882 HIV-negative participants. Participants received two doses of MVC-COV1901 28 days apart.

RESULTS

No vaccine-related serious adverse events (SAEs) were recorded. Seroconversion rates (SCRs) of 100% and 99.8% were achieved in PWH and comparators, respectively, 28 days after the second dose. After adjusting for sex, age, BMI category, and comorbidity, the adjusted GMT ratio of comparator/PWH was 3.2 (95% CI 2.5-4). A higher CD4/CD8 ratio was associated with a higher GMT (R = 0.27, p = 0.039). MVC-COV1901 has shown robust safety but elicited weaker immune responses in PWH.

CONCLUSIONS

Further investigations may be needed to determine whether PWH require distinct immunization strategies with improved immunogenicity. The main study is registered at ClinicalTrials.gov (NCT04695652).

Evaluation of effectiveness, safety and cost-benefit of the 23- valent pneumococcal capsular polysaccharide vaccine for HIV-Infected patients

INTRODUCTION

Due to the lack of understanding of the protective effects and safety of 23-valent pneumococcal polysaccharide vaccine (PPV23) in immune-deficient populations, the vaccination rate of PPV23 among HIV-infected patients is still very low in China. The main objectives of this study were to determine whether the efforts to assess measures for the prevention of pneumococcal pneumonia are still worthwhile, and provide designated vaccination program of HIV-infected persons for government policy based on.

METHODS

60 HIV-infected adults in Lanshan county who had never been vaccinated with any pneumococcal vaccine were enrolled in this study, voluntary vaccination of PPV23 and One-year follow-up after vaccination can be completed.

RESULT

76.67% patients (46/60) had serologic response at 12 months after vaccine, CD4 count(≤500 cells/ul or > 500 cells/ul) and Month from diagnosis to first antiviral therapy (≤1 month or > 1 month) were related to antibody responses (p < 0.05).In this study, PPV23 was well tolerated, no adversereaction was reported.11 Streptococcus pneumoniae pneumonia (9.17%,11/120) occurred in the Unvaccinated group and 1 case(1.67%,1/60)in the vaccination group within one year after vaccination(Fisher's exact probability, P = 0.225). The VE was 81.79%. The per capita benefit was 39.32 dollars, thebenefit-costratio = 1.19. There are significant statistical differences between the vaccinated group and the non-vaccinated group in outpatient costs (p < 0.05, 95 %CI: 9.29-32.11), Medicine costs (p = 0.017, 95 %CI: 2.47-24.44), and disease related indirect costs (p = 0.038, 95 %CI: 0.93-33.63) within one year of vaccination.

CONCLUSION

Our study results showed that PPV23 can be safely and effectively administered to HIV-1 infected individuals and effectively preventing Streptococcal pneumonia. Considering the cost-benefit of vaccination among HIV-infected persons, as it has been reported in our study, it is necessary to promote the widespread use of the vaccine among HIV-infected persons in the future.

Single-Dose 13-Valent Conjugate Pneumococcal Vaccine in People Living With HIV – Immunological Response and Protection

Background

Patients living with HIV (PLHIV) are prone to invasive pneumococcal disease. The 13-valent conjugated pneumococcal vaccine (PCV13) is currently recommended for all PLHIV, followed in most guidelines by a 23-valent polysaccharide pneumococcal vaccine. Data are scarce concerning the immunological efficacy of PCV13 among PLHIV.

Objective

To assess the immunological response at one month, and the immunological protection at 1-, 6-, and 12 months in PLHIV with a CD4 cell count above 200 cells/µl after a single dose of PCV13, as measured by both ELISA and opsonophagocytic assay (OPA).

Methods

PLHIV with CD4 cell count >200 cells/µl were included. Specific IgG serum concentrations for eight serotypes by ELISA and seven serotypes by OPA were measured at baseline, 1-, 6-, and 12 months after the PCV13 vaccination. Global response was defined as a two-fold increase from baseline of specific IgG antibody levels (μg/ml) assayed by ELISA or as a four-fold increase in OPA titer from baseline, for at least five serotypes targeted by PCV13. Global protection was defined as an IgG-concentration ≥1 µg/ml by ELISA or as an opsonization titer ≥LLOQ by OPA for at least five tested serotypes targeted by PCV13. Factors associated with global response and global protection were assessed using logistic regression.

Results

Of the 38 PLHIV included, 57.9% and 63.2% were global responders, 92.1% and 78.9% were globally protected at one month, and 64.7% and 55.9% were still protected at 12 months, by ELISA and OPA respectively. A CD4/CD8 ratio of >0.8 was significantly associated with a better global response by OPA (OR=6.11, p=0.02), and a CD4 nadir <200 was significantly associated with a poorer global response by ELISA (OR=0.22, p=0.04). A CD4 cell count nadir <200 and age over 50 years were associated with poorer global protection by OPA at M1 (OR=0.18, p=0.04) and M12 (OR= 0.15, p=0.02), respectively. Plasma HIV RNA viral load <40 copies/ml was significantly associated with a better global protection at M1 by ELISA and OPA (OR=21.33, p=0.025 and OR=8.40, p=0.04)

Conclusion

Vaccination with PCV13 in these patients induced immunological response and protection at one month. At one year, more than half of patients were still immunologically protected.

Immunogenicity of pneumococcal vaccination in HIV infected individuals: A systematic review and meta-analysis

BACKGROUND

The objective of this systematic review and meta-analysis was to summarise the literature regarding the immunogenicity of pneumococcal conjugate vaccines (PCV) and pneumococcal polysaccharide vaccines (PPSV) in adult people living with HIV (PLWH) in the era of advanced combination antiretroviral therapy (cART).

METHODS

The systematic review protocol was published online (PROSPERO ID: CRD 42020153137). We searched Medline (Ovid), EMBASE (Ovid), and the Global Health Library for publications from 2000 to June 11, 2020. We included all studies in adult PLWH that reported vaccine immunogenicity outcomes. The primary outcome was seroconversion rate (SCR) after PCV, PPSV and PCV/PPSV combined. For random-effects meta-analysis, we included studies defining SCR as a ≥ 2-fold increase in IgG from baseline, and reporting SCR for serotypes 6B, 14, or overall SCR, 1-3 months after vaccination.

FINDINGS

Our search identified 1597 unique studies, of which 115 were eligible for full-text assessment. Of these, 39 met the inclusion criteria (11 RCTs; 28 cohort studies). A high degree of heterogeneity was observed. Nineteen studies were included in the meta-analysis. Pooled overall SCRs were 42% (95% CI 30-56%), 44% (95% CI 33-55%) and 57% (95% CI 50-63%) for PLWH who received PPSV, PCV or a combination of PCV/PPSV, respectively. Compared to PPSV alone, a combination of PCV/PPSV yielded higher SCRs (OR 2.24 95% CI 1.41- 3.58), whereas we did not observe a significant difference in SCR between PCV and PPSV23 alone. There were no statistically significant differences in geometric mean post-vaccination antibody concentrations between vaccination schedules. Vaccination at higher CD4 cell counts improved immunogenicity in 8/21 studies, especially when PCV was administered. No studies assessed the long-term immunogenicity of PCV followed by PPSV23. Quality of evidence ranged from poor (n = 19) to good quality (n = 7). A limited number of pneumococcal serotypes was assessed in the majority of studies.

INTERPRETATION

We show that the recommended immunisation schedule consisting of a combination of PCV13/PPSV23, is immunogenic in PLWH in the era of advanced cART. However, the durability of this vaccination schedule remains unknown and must be addressed in future research. Vaccination with PCV should be delayed until immunological recovery (CD4>200) in recently diagnosed PLWH for optimal immunogenicity. The evidence gathered here supports wide implementation of the combination of PCV/PPSV23 for all PLWH. We recommend reassessment of this strategy once higher-valent PCVs become available.

FUNDING

HMGG is funded by a public research grant of ZonMw (project number 522004005).

Long-term Immune Response to Yellow Fever Vaccination in Human Immunodeficiency Virus (HIV)-Infected Individuals Depends on HIV RNA Suppression Status: Implications for Vaccination Schedule

Background

In human immunodeficiency virus (HIV)-infected individuals, the immune response over time to yellow fever vaccination (YFV) and the necessity for booster vaccination are not well understood.

Methods

We studied 247 participants of the Swiss HIV Cohort Study (SHCS) with a first YFV after HIV diagnosis and determined their immune responses at 1 year, 5 years, and 10 years postvaccination by yellow fever plaque reduction neutralization titers (PRNTs) in stored blood samples. A PRNT of 1:≥10 was regarded as reactive and protective. Predictors of vaccination response were analyzed with Poisson regression.

Results

At vaccination, 82% of the vaccinees were taking combination antiretroviral therapy (cART), 83% had suppressed HIV RNA levels (<400 copies/mL), and their median CD4 T-cell count was 536 cells/μL. PRNT was reactive in 46% (95% confidence interval [CI], 38%-53%) before, 95% (95% CI, 91%-98%) within 1 year, 86% (95% CI, 79%-92%) at 5 years, and 75% (95% CI, 62%-85%) at 10 years postvaccination. In those with suppressed plasma HIV RNA at YFV, the proportion with reactive PRNTs remained high: 99% (95% CI, 95%-99.8%) within 1 year, 99% (95% CI, 92%-100%) at 5 years, and 100% (95% CI, 86%-100%) at 10 years.

Conclusions

HIV-infected patients' long-term immune response up to 10 years to YFV is primarily dependent on the control of HIV replication at the time of vaccination. For those on successful cART, immune response up to 10 years is comparable to that of non-HIV-infected adults. We recommend a single YFV booster after 10 years for patients vaccinated on successful cART, whereas those vaccinated with uncontrolled HIV RNA may need an early booster.

Long-Term Serological Response to 13-Valent Pneumococcal Conjugate Vaccine Versus 23-Valent Polysaccharide Vaccine in HIV-Infected Adults

Introduction

Long-term comparative immunologic response to 13-valent pneumococcal conjugate vaccine (PCV13) versus 23-valent polysaccharide vaccine (PPV23) among HIV-infected adults has not yet been investigated.

Methods

In this prospective pilot study, we quantified in HIV-positive adults serotype-specific IgG concentrations of the 12 pneumococcal serotypes shared by both vaccines 5 years after vaccination with two doses of PCV13 8 weeks apart (group 1) or one dose of PPV23 (group 2) and compared them with those assessed prior to vaccination (BL) and after 1 year (T1). Comparison of immunogenicity was based on geometric mean concentration (GMC), proportion of individuals with ≥ twofold increase from BL in specific antibody concentration against ≥ 2 serotypes and percentage of individuals with serotype-specific IgG ≥ 0.35 μg/ml, ≥ 1 μg/ml and ≥ individual serotype-specific correlates of protection.

Results

We included 91 subjects (median CD4⁺ 650 cells/µl, > 90% with HIV-RNA < 50 copies/ml); patients in groups 1 (n = 42) and 2 (n = 49) were homogeneous for the main characteristics. GMCs were significantly higher in the PCV13 group than in the PPV23 group for serotype 19F (p = 0.003). Both vaccines revealed higher significant GMCs to most serotypes compared with BL, i.e., eight in group 1 vs. seven in group 2. With respect to T1, GMCs decreased significantly in the PCV13 group for eight vs. ten serotypes in the PPV23 group. More participants in the PCV13 group had ≥ 2 increase from BL in antibody levels to ≥ 2 serotypes compared with the PPV23 group (78.6% vs. 59.2%, p = 0.042). Overall, the percentage of subjects with serotype-specific IgG ≥ 0.35 μg/ml, ≥ 1 μg/ml and ≥ individual serotype-specific correlates of protection was similar between groups.

Conclusion

In this study with HIV-positive adults with a favorable viro-immunologic profile, both vaccines were shown to achieve a long-term durable serologic response. We found minor differences in immunogenicity between the two vaccines, which favored PCV13 over PPV23 5 years after immunization.

Trial Registration

ClinicalTrials.gov identifier, NCT02123433.

Electronic supplementary material

The online version of this article (10.1007/s40121-019-0256-z) contains supplementary material, which is available to authorized users.

Treating bacterial pneumonia in people living with HIV

Introduction: Bacterial pneumonia remains an important cause of morbidity and mortality in people living with HIV (PLWH) in the antiretroviral therapy (ART) era. In addition to being immunocompromised, as reflected by low CD4 cell counts and elevated HIV viral loads, PLWH often have other behaviors associated with an increased risk of pneumonia including smoking and injected drug use. As PLWH are aging, comorbid conditions such as chronic obstructive pulmonary disease (COPD), cancers, and cardiovascular, renal and liver diseases are emerging as additional risk factors for pneumonia. Pathogens are often similar to those in HIV-uninfected individuals; however, PLWH are at risk for unusual and/or multi-drug resistant organisms causing bacterial pneumonia based, in part, on their CD4 cell counts and other exposures. Areas covered: In this review, we focus on the recognition and management of bacterial community-acquired pneumonia (CAP) in PLWH. Along with antimicrobial treatment, we discuss prevention strategies such as vaccination and smoking cessation. Expert opinion: Early initiation of ART after HIV infection can decrease the risk of pneumonia. Improved efforts at vaccination, smoking cessation, and reduction of other substance use are urgently needed in PLWH to decrease the risk for bacterial pneumonia. As PLWH are aging, comorbidities are additional risk factors for bacterial CAP.

Vaccination in the Adult Patient Infected with HIV: A Review of Vaccine Efficacy and Immunogenicity

Patients infected with HIV remain at increased risk of mortality and morbidity from diseases that are preventable with vaccines partly due to the persisting immunopathology that results in impaired responses to vaccination despite virologic suppression. Because data on clinical effectiveness in patients who are immunocompromised remain limited, undervaccination of individuals with HIV poses a major concern. Multiple societies have published recommendations on vaccination in individuals infected with HIV. Many of these recommendations are based on extrapolation of data from clinical trials that usually exclude patients with HIV, although there is a growing body of data from patients infected with HIV as well. In this review, we describe the available literature on vaccine response in the adult patient with HIV as measured by immunogenicity or vaccine efficacy.

Serological responses to revaccination against HBV in HIV-positive patients born in the era of nationwide neonatal HBV vaccination

BACKGROUND

Serological responses to revaccination against hepatitis B virus (HBV) are unclear in HIV-positive adults who had undergone neonatal HBV vaccination and whose antibodies against HBV had waned in the era of combination antiretroviral therapy (cART).

METHODS

Between 2000 and 2017, 666 HIV-positive men who have sex with men (MSM) who were born after 1986, when nationwide neonatal HBV vaccination programme was implemented in Taiwan, were included for analyses. A serological response was defined when a hepatitis B surface antibody (anti-HBs) titre ≥10 mIU/mL was measured 4-24 weeks after the third dose of HBV vaccination.

RESULTS

During the study period, 295 (48.7%) HIV-positive MSM (mean age, 23.2 years) who had lost HBV seroprotection were eligible for revaccination; 171 (58.0%) received at least 1 dose (20-μg) of HBV vaccine and 116 (39.3%) completed the 3-dose schedule. The serological response rate to 3 doses of HBV revaccination was 74.0% and the rate of high-titre response (anti-HBs titre ≥100 mIU/mL) was 46.0%. The CD4 count before the first dose (per 50-cell/μL increment, adjusted odds ratio, 1.14; 95% confidence interval, 1.01-1.29) was positively associated with the serological response. The incident rate of HBV infection was 9.2 per 1000 person-years of follow-up among the patients who were non-responders after revaccination.

CONCLUSIONS

Despite HBV vaccination in the neonatal period, the serological response rate to HBV revaccination in HIV-positive MSM was modest and could wane rapidly. Regular testing of anti-HBs should be integrated into the HIV care despite cART containing HBV-active agents.

Vaccinations for the HIV-Infected Adult: A Review of the Current Recommendations, Part I

Vaccination is a critical component for ensuring the health of those living with the human immunodeficiency virus (HIV) by protection against vaccine-preventable diseases. Since HIV-infected persons may have reduced immune responses and shorter durations of protection post-vaccination, HIV-specific guidelines have been published by global and national advisory organizations to address these potential concerns. This article provides a comprehensive review of the current guidelines and evidence-based data for vaccinating HIV-infected adults, including guidance on modified vaccine dosing and testing strategies, as well as safety considerations, to enhance protection among this vulnerable population. In the current article, part I of the two-part series, inactivated vaccines with broad indications as well as vaccines for specific risk and age groups will be discussed.

Predictors of humoral response to recommended vaccines in HIV-infected adults

Humoral response to vaccination has been found to be inadequate in individuals infected with the human immunodeficiency virus (HIV). We retrospectively assessed antibody responses to three routinely recommended vaccines, against hepatitis B, hepatitis A and S. pneumoniae, in HIV-infected individuals. Data regarding age at HIV diagnosis, years of infection, sex, nationality, HIV mode of transmission, CD4 cell count, nadir CD4 count, plasma viral load, HIV stage, insurance status, educational level and treatment with Highly Active Antiretroviral Therapy (HAART) were collected. Univariate and multivariate analysis was performed in order to detect factors associated with response to vaccination. 437 patients were assessed for hepatitis B, 627 patients for hepatitis A and 66 patients for S. pneumoniae serologic vaccine responsiveness. Regarding hepatitis B and hepatitis A, education level and insurance status were the only predictors of response. As for S. pneumoniae vaccination HAART and control of viremia were correlated with better response to vaccination.

Brief Report: Immunization of HIV-Infected Adults in the UK With Haemophilus influenzae b/Meningococcal C Glycoconjugate and Pneumococcal Polysaccharide Vaccines

U.K. guidelines for vaccinating HIV-infected adults against bacteria are based on limited data. We compared antibody responses between 211 HIV-infected and 73 HIV-uninfected adults vaccinated with pneumococcal polysaccharide vaccine (PPV) and Haemophilus influenzae b/meningococcal C polysaccharide-tetanus toxoid glycoconjugate vaccine (Hib/MenC-TT). IgG responses to Hib/MenC-TT were not significantly different. PPV induced median IgGs >1.3 μg/mL for 10/12 serotypes among HIV-uninfected participants and 5/12 in HIV-infected participants. HIV-uninfected adults had higher post-vaccination IgGs than HIV-infected adults for 4/12 serotypes (P < 0.001). Responses did not associate with CD4 count or viral suppression. In a U.K. HIV-infected population, Hib/MenC-TT induced similar responses to HIV-uninfected adults, whereas PPV induced poor responses.

Vaccination coverage in a cohort of HIV-infected patients receiving care at an AIDS outpatient clinic in Espírito Santo, Brazil

This cross-sectional study assessed the immunization status of human immune deficiency virus (HIV)-infected patients receiving care at an outpatient clinic in Brazil. The sociodemographic characteristics, CD4 count and HIV viral load of 281 out of 612 adult outpatients were analyzed. A total of 331 patients were excluded because of no availability of vaccination cards. Chi-square or Fisher's exact test were used. Immunization coverage was higher for diphtheria/tetanus (59.79%) and hepatitis B (56.7%), and lowest for hepatitis A (6.8%) and for meningococcal group C (6%). Only 11.74% of the patients had received the influenza virus vaccine yearly since their HIV-infection diagnosis. No vaccination against influenza (p<0.034) or hepatitis B (p<0.029) were associated with CD4 counts <500cells/mL; no vaccination against flu or pneumococcus were associated with detectable HIV viral load (p<0.049 and p<0.002, respectively). Immunization coverage is still very low among HIV-infected adults in this setting despite recommendations and high infection-related mortality.

Production of IgG antibodies to pneumococcal polysaccharides is associated with expansion of ICOS+ circulating memory T follicular-helper cells which is impaired by HIV infection

Dysfunction of T follicular-helper (T_FH) cells is a possible cause of impaired germinal centre (GC) and IgG antibody responses in individuals with human immunodeficiency virus-1 (HIV-1) infection and might contribute to decreased magnitude and isotype diversification of IgG antibodies to pneumococcal polysaccharides (PcPs). We examined the production of IgG1 and IgG2 antibodies to PcPs 4, 6B, 9V and 14 by enumerating antibody secreting cells (ASCs) at day (D) 7 and determining fold-increase in serum antibody levels at D28 after vaccination with unconjugated PcPs in HIV seronegative subjects (n = 20) and in HIV patients who were receiving antiretroviral therapy (ART) (n = 28) or who were ART-naive (n = 11) and determined their association with ICOS⁺ and ICOS^- circulating memory T_FH (cmT_FH) cells (CD4⁺CD45RA^-CD27⁺CXCR5⁺PD-1⁺) and short lived plasmablasts (SPBs) at D7, and with PcP-specific and total IgM⁺ and IgG⁺ memory B cells at D0. In HIV seronegative subjects, production of IgG1⁺ and IgG2⁺ ASCs was consistently associated with the frequency of ICOS⁺ cmT_FH cells but not ICOS^- cmT_FH cells or memory B cells. In contrast, post-vaccination ASCs in HIV patients, regardless of ART status, were lower than in HIV seronegative subjects and not associated with ICOS⁺ cmT_FH cells, the expansion of which was absent (ART-naive patients) or much lower than in HIV seronegative subjects (ART-treated patients). Production of SPBs was also lower in ART-naive patients. Fold-increase in IgG2 antibodies at D28 also correlated with ICOS⁺ cmT_FH cells at D7 in HIV seronegative subjects but not in HIV patients. These novel findings provide evidence that ICOS⁺ cmT_FH cells contribute to the regulation of PcP-specific IgG antibody responses, including isotype diversification, and that T_FH cell dysfunction may be a cause of impaired PcP-specific IgG antibody responses and increased susceptibility to pneumococcal disease in HIV patients.

Immunization of HIV-infected adult patients - French recommendations

Human immunodeficiency virus (HIV)-infected patients remain at increased risk of infection including vaccine-preventable diseases. Vaccines are therefore critical components in the protection of HIV-infected patients from an increasing number of preventable diseases. However, missed opportunities for vaccination among HIV-infected patients persist and vaccine coverage in this population could be improved. This article presents the French recommendations regarding immunization of HIV-infected adults in the light of the evidence-based literature on the benefits and the potential risks of vaccines among this vulnerable population.

Chronic HIV-1 Infection Induces B-Cell Dysfunction That Is Incompletely Resolved by Long-Term Antiretroviral Therapy

OBJECTIVES

To determine the effect of long-term antiretroviral therapy (ART) on HIV-1-induced B-cell dysfunction.

DESIGN

Comparative study of ART-naive and ART-treated HIV-infected patients with non-HIV controls.

METHODS

B-cell dysfunction was examined in patients with HIV-1 infection (n = 30) who had received ART for a median time of 9.25 years (range: 1.3-21.7) by assessing proportions of CD21 B cells (a marker of B-cell exhaustion) and proportions of tumor necrosis factor-related apoptosis-inducing ligand or B and T lymphocyte attenuator B cells, and serum levels of immunoglobulin free light chains (markers of B-cell hyperactivation). The association of these markers with serum levels of IgG1 and IgG2, and production of IgG antibodies after vaccination with pneumococcal polysaccharides were also examined. ART-naive patients with HIV (n = 20) and controls (n = 20) were also assessed for comparison.

RESULTS

ART-treated patients had increased proportions of CD21 and tumor necrosis factor-related apoptosis-inducing ligand B cells and, furthermore, although proportions of B and T lymphocyte attenuator B cells were not significantly different from controls, they correlated negatively with CD21 B cells. Proportions of CD21 B cells also correlated negatively with current CD4 T-cell counts. In ART-naive patients with HIV, free light chains correlated with CD21 B cells and IgG1, but not IgG2. Serum IgG2:IgG1 ratios were substantially lower than normal in patients with HIV and did not resolve on ART. In ART-treated patients, IgG antibody responses to pneumococcal polysaccharides after vaccination were not associated with markers of B-cell dysfunction.

CONCLUSIONS

B-cell dysfunction persists in patients with HIV receiving long-term ART. The causes and consequences of this require further investigation.

Immunogenicity and Safety of the 13-Valent Pneumococcal Conjugate Vaccine versus the 23-Valent Polysaccharide Vaccine in Unvaccinated HIV-Infected Adults: A Pilot, Prospective Controlled Study

Objectives

Definition of the optimal pneumococcal vaccine strategy in HIV-infected adults is still under evaluation. We aimed to compare immunogenicity and safety of the 13-valent pneumococcal conjugate vaccine (PCV13) versus the 23-valent polysaccharide vaccine (PPSV23) in HIV-infected adults.

Methods

We performed a pilot, prospective controlled study enrolling HIV-infected pneumococcal vaccine-naïve outpatients, aged 18–65 years with CD4 counts ≥200 cells/μL. Eligible subjects were recruited into two parallel groups: group 1 (n = 50) received two doses of PCV13 eight weeks apart, and group 2 (n = 50) received one dose of PPSV23, as part of their standard of care. Anti-pneumococcal capsular polysaccharide immunoglobulin G concentrations were quantified by ELISA at baseline, 8, 24 and 48 weeks. Clinical and viro-immunological follow-up was performed at the same time points. Unvaccinated, age-matched HIV-negative adults (n = 100) were also enrolled as baseline controls.

Results

Pre-vaccination specific IgG titers for each pneumococcal antigen did not differ between study groups but they were constantly lower than those from the HIV-negative controls. After immunization, significant increases in IgG titers were observed in both study groups at each time point compared to baseline, but response to serotype 3 was blunted in group 1. Antibody titers for each antigen did not differ between study groups at week 48. Overall, the proportion of subjects achieving seroprotection and seroconversion to all serotypes was comparable between groups. A marked decrease in IgG levels over time was observed with both vaccines. No relevant adverse reactions were reported in either group.

Conclusions

In this population with favorable immune profile, no relevant differences were observed in immunogenicity between PCV13 and PPSV23. Both vaccines were safe and well tolerated.

Trial Registration

ClinicalTrials.gov NCT02123433

Long-term immune responses and comparative effectiveness of one or two doses of 7-valent pneumococcal conjugate vaccine (PCV7) in HIV-positive adults in the era of combination antiretroviral therapy

Introduction

HIV infection impairs maintenance of immunological memory, yet few studies of HIV-positive adults receiving 7-valent pneumococcal conjugate vaccine (PCV7) have followed them beyond the first year. We determined and compared the durability of serological responses and the clinical outcomes of HIV-positive adults annually for five years following vaccination with one or two doses of PCV7.

Methods

In this non-randomized clinical trial, 221 pneumococcal vaccine-naïve HIV-positive adults receiving one (n=109) or two doses four weeks apart (n=112) of PCV7 between 2008 and 2010 were longitudinally followed for evaluation of significant serological response and for episodes of pneumonia and invasive pneumococcal disease.

Results

At the time of vaccination, the two groups were well matched for age, risk factors, combination antiretroviral therapy (cART) coverage, CD4 count and plasma HIV RNA load (PVL). At the end of five years, the CD4 counts for the one- and two-dose groups had increased from 407 and 406 to 550 and 592 cells/µL, respectively, and 82.4 and 81.6% of the participants had fully suppressed PVL. Significant immune responses to ≥2 serotypes persisted for 67.9 vs 78.6%, 64.2 vs 71.4%, 66.1 vs 71.4%, 57.8 vs 69.6% in the second, third, fourth and fifth years after one and two doses of PCV7 in the intention-to-treat analysis, respectively. In multivariate analysis, immunization with two doses of PCV7 (odds ratio (OR) 1.71, 95% confidence interval (CI) 1.10 to 2.65, p=0.016), concurrent cART (OR 2.16, 95% CI 1.16 to 4.00, p=0.015) and CD4 proliferation (OR 1.12, 95% CI 1.01 to 1.27, p=0.031) were predictive of persistent serological responses in the fifth year. Only one patient in the one-dose group had documented pneumococcal pneumonia (non-bacteraemic) and none had invasive pneumococcal disease in the 6.5 years of follow-up.

Conclusions

One or two doses of PCV7 achieve durable seroprotective responses in HIV-treated participants; however, two doses may be more robust than one dose in a larger study population or in real-world populations with less cART coverage.

Pneumococcal vaccination among HIV-infected adult patients in the era of combination antiretroviral therapy

HIV-infected patients remain at higher risk for pneumococcal disease than the general population despite immune reconstitution and suppression of HIV replication with combination antiretroviral therapy. Vaccination with 23-valent pneumococcal polysaccharide vaccine (PPV23) composed of T-cell-independent antigens has been recommended to reduce the risk of pneumococcal disease in HIV-infected adults. However, given the heterogeneity of study design, execution and subjects enrolled, studies examining serological responses to PPV23 yielded conflicting results and observational studies of clinical effectiveness only provided moderate evidence to support the routine use of PPV23 in HIV-infected adults. Pneumococcal conjugate vaccine (PCV), with conjugation of the capsular polysaccharide to a protein carrier, is more immunogenic than PPV23 and has been demonstrated to protect against pneumococcal disease in HIV-infected children and recurrent invasive pneumococcal disease in HIV-infected adolescents and adults. Guidelines have recently been revised to recommend that HIV-infected patients aged 19 y or older receive one dose of 13-valent pneumococcal conjugate vaccine (PCV13) followed by a booster vaccination with PPV23. In this paper, we review the studies using different vaccination strategies to improve immunogenicity among HIV-infected adult patients.

HIV-associated memory B cell perturbations

Memory B-cell depletion, hyperimmunoglobulinemia, and impaired vaccine responses are the hallmark of B cell perturbations inhuman immunodeficiency virus (HIV) disease. Although B cells are not the targets for HIV infection, there is evidence for B cell, especially memory B cell dysfunction in HIV disease mediated by other cells or HIV itself. This review will focus on HIV-associated phenotypic and functional alterations in memory B cells. Additionally, we will discuss the mechanism underlying these perturbations and the effect of anti-retroviral therapy (ART) on these perturbations.

Pneumococcal vaccines: understanding centers for disease control and prevention recommendations

Streptococcus pneumoniae infection is a common and serious health problem that is best prevented by the pneumococcal vaccine. The first vaccine approved by the U.S. Federal Drug Administration in 1977 contained 14 polysaccharide antigens. An improved vaccine introduced in 1983 included 23 polysaccharide antigens. Both vaccines were effective for immunocompetent adults; however, young children and immunocompromised adults remained susceptible. A pediatric vaccine was developed consisting of the capsular antigens of seven pneumococcal serotypes commonly found in children. The antigens in this preparation are covalently conjugated to diphtheria protein to make them more antigenic. The conjugate vaccine was expanded to include 13 serotypes by 2010. Although more immunogenic, the conjugate vaccine has fewer serotypes than the older 23-valent vaccine. The U.S. Centers for Disease Control and Prevention recommend that children at risk for pneumococcal pneumonia as defined by the presence of chronic disease should receive the 13-valent conjugated vaccine. Adults at risk for pneumococcal pneumonia, which includes those over 65 years of age and those who have a chronic disease, should receive the 23-polysaccharide vaccine. Immunosuppressed patients of any age should receive both vaccines. Adults should be revaccinated once at age 65 years or older with the 23-polysaccharide vaccine provided that at least 5 years have elapsed since the previous vaccination.

Antibody Response is More Likely to Pneumococcal Proteins Than to Polysaccharide After HIV-associated Invasive Pneumococcal Disease

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals are at increased risk of invasive pneumococcal disease (IPD). In order to assess the immunogenicity of pneumococcal proteins and polysaccharide, we investigated protein and serotype-specific antibody responses after HIV-associated IPD.

METHODS

Specific antipneumococcal immunoglobulin G to 27 pneumococcal protein antigens and 30 serotype polysaccharides was measured in plasma before and after IPD in HIV-infected individuals and compared to HIV-infected individuals without IPD.

RESULTS

Over time, 81% of IPD cases responded to at least 1 protein compared to 51% of non-IPD controls. HIV IPD cases responded to more proteins than non-IPD controls (8.6 ± 8.4 vs 4.2 ± 7.6 proteins; P = .01), and had a significantly higher probability of yielding an antibody response to the proteins PiaA, PsaA, and PcpA. Twenty-two percent of HIV-infected individuals with IPD had a serotype-specific antibody response. Younger age at the time of IPD was the only predictor of a serotype-specific pneumococcal antibody response, whereas we did not identify predictors of a protein-specific antibody response.

CONCLUSIONS

Antibody responses occurred more frequently to pneumococcal proteins than to polysaccharide, and protein antibodies persisted for longer than polysaccharide-specific antibodies. PcpA, PiaA, and PsaA were the most immunogenic proteins.

Response to Pneumococcal Polysaccharide Vaccination in Newly Diagnosed HIV-Positive Individuals

BACKGROUND

Newly diagnosed HIV-positive individuals are 35 to 100-fold more susceptible to Streptococcus pneumoniae infection compared to non-infected individuals. Therefore, the 23-valent pneumococcal polysaccharide vaccine (PPV23) has previously been recommended, though efficacy and effectiveness of vaccination remains controversial. Early severe B cell dysfunction is a central feature of HIV infection. The specific nature of the immune cells involved in the production of protective antigen-specific antibodies in HIV-positive individuals remains to be elucidated.

OBJECTIVES

Evaluate the antibody and antigen-specific B cell response to the 23-valent pneumococcal polysaccharide vaccine in newly diagnosed HIV-positive patients. Moreover, determine if newly diagnosed patients with CD4<200 cells/μl benefit from 6-12 months of HAART, allowing partial viral suppression and immune reconstitution, prior to immunization.

METHODS

Newly diagnosed HIV-positive patients with CD4>200 cells/μl and CD4<200 cells/μl were immunized with PPV23. Patients with CD4<200 cells/μl received either immediate or delayed immunization following 6-12 months of HAART. Antibody responses, opsonophagocytic activity and phenotypic analysis of pneumococcal polysaccharide-specific B cells were studied.

RESULTS

Newly diagnosed HIV-positive patients demonstrated CD4-dependent increases in antibody and opsonophagocytic titers thought to be commensurate with protection. Functional opsonophagocytic titers of patients with CD4<200 cells/μl immunized immediately compared to patients with CD4<200 cells/μl receiving HAART for 6-12 months were not significantly different. Pneumococcal polysaccharide-specific B cells were distributed evenly between IgM memory and switched memory B cells for all groups, but IgM memory B cells were significantly lower than in HIV-negative individuals.

CONCLUSIONS

Despite CD4-dependent pneumococcal polysaccharide-specific deficiencies in newly diagnosed HIV-positive patients, vaccination was beneficial based on opsonophagocytic titers for all newly diagnosed HIV-positive groups. In HIV-positive patients with CD4<200 cells/μl, 6-12 months of HAART did not improve opsonophagocytic titers or antibody concentrations. Based on these findings, immunization with the 23-valent pneumococcal polysaccharide vaccine should not be delayed in newly diagnosed HIV-positive patients with CD4<200 cells/μl.

Response to Pneumococcal Polysaccharide Vaccination in HIV-Positive Individuals on Long Term Highly Active Antiretroviral Therapy

Background and objectives

Streptococcus pneumoniae continues to cause serious infections in HIV-positive individuals in the era of highly active anti-retroviral therapy. This led to the recommendation to revaccinate HIV-positive individuals with PPV23 five years after primary vaccination. The benefits of revaccination and the impact of long term highly active anti-retroviral therapy (HAART) on antigen-specific B cell reconstitution have remained unclear thus far and were investigated.

Design and methods

We assessed antibody levels, opsonophagocytic activity and phenotype of pneumococcal polysaccharide (PPS) specific-B cells post-revaccination in long term HAART cohorts stratified according to CD4 count as group A (CD4>200) and group B (CD4<200). Anti-PPS IgG, IgM and functional antibody response against vaccine serotypes 14 and 23F were measured by ELISA and opsonophagocytic assay followed by phenotypic analysis of PPS14 and 23F-specific B cells using fluorescently labeled PPS.

Results

Significant increases in total and functional antibody titers were noted in groups A and B post-vaccination concomitant with significant rise in PPS-specific IgM memory B cells, a critical B cell subset required for protection against PPS although the overall response remained significantly diminished compared to HIV-negative volunteers.

Conclusion

Comparable increases in opsonophagocytic titers between study groups A and B concomitant with a comparable rise in PPS-specific IgM memory B cells indicate revaccination to be beneficial regardless of the degree of CD4 T cell reconstitution. These findings emphasize the importance of defining effective vaccination practices amongst high-risk individuals.

Pneumococcal vaccine and patients with pulmonary diseases

Chronic pulmonary diseases are chronic diseases that affect the airways and lung parenchyma. Examples of common chronic pulmonary diseases include asthma, bronchiectasis, chronic obstructive lung disease, lung fibrosis, sarcoidosis, pulmonary hypertension, and cor pulmonale. Pulmonary infection is considered a significant cause of mortality in patients with chronic pulmonary diseases. Streptococcus pneumoniae is the leading isolated bacteria from adult patients with community-acquired pneumonia, the most common pulmonary infection. Vaccination against S. pneumoniae can reduce the risk of mortality, especially from more serious infections in both immunocompetent and immunocompromised patients. Patients with chronic pulmonary diseases who take steroids or immunomodulating therapy (eg, methotrexate, anti-tumor necrosis factor inhibitors), or who have concurrent sickle cell disease or other hemoglobinopathies, primary immunodeficiency disorders, human immunodeficiency virus infection/acquired immunodeficiency syndrome, nephrotic syndrome, and hematologic or solid malignancies should be vaccinated with both 13-valent pneumococcal conjugate vaccine and the pneumococcal polysaccharide vaccine 23-valent.

Revaccination with 7-valent pneumococcal conjugate vaccine elicits better serologic response than 23-valent pneumococcal polysaccharide vaccine in HIV-infected adult patients who have undergone primary vaccination with 23-valent pneumococcal polysaccharide vaccine in the era of combination antiretroviral therapy

HIV-infected adults who had received 23-valent pneumococcal polysaccharide vaccine (PPV23) five years or more earlier consecutively underwent revaccination with one dose of PPV23 (127 subjects) from December 2005 through October 2007, or upon change in standard of care, non-randomly one (50) or two doses (44) of 7-valent pneumococcal conjugate vaccine (PCV7) from October 2008 through June 2010. Serologic response was defined as ≥ 2-fold increase in the IgG level plus a level ≥ 1000ng/ml 48 weeks following revaccination. At week 48, the response rate was significantly higher in the 2-dose PCV7 group compared with that in the 1-dose PCV7 or PPV23 group (63.6% vs 32.0% vs 8.7%, respectively; P<0.05). Revaccination with one dose of PCV7 (AOR, 4.57), two doses of PCV7 (AOR, 22.66), and CD4 >350 cells/μl (AOR, 3.24) and undetectable viral load (AOR, 3.87) at revaccination were statistically significantly associated with a better serologic response at week 48. Despite the limitation that study arms were neither randomized nor contemporaneous, we conclude that revaccination with PCV7 appears to elicit a better serologic response than PPV23 in the HIV-infected adults who have received PPV23 five years or more earlier (clinical trial registration number: NCT00885625).

Long-term immune responses to vaccination in HIV-infected patients: a systematic review and meta-analysis

Vaccine-induced antibodies may wane more quickly in persons living with human immunodeficiency virus (HIV) than in healthy individuals. We reviewed the literature on vaccines routinely recommended in HIV-infected patients to estimate how seroprotection decreases over time in those who initially responded to immunization. For each study retrieved from the literature, the decrease of seroprotection was modeled with a log binomial generalized linear model, and data were pooled in a meta-analysis to provide estimates of seroprotection 2 and 5 years after the last vaccine administration. Our analyses confirmed that the duration of seroprotection was shorter in HIV-infected patients and that with current guidelines, a substantial proportion of patients would have lost protective antibodies before a booster was proposed. We therefore discuss the implications for the monitoring of antibody levels and timing of revaccination in these patients.

Pneumococcal immunization in immunocompromised hosts: where do we stand?

Immunocompromised patients are all at risk of invasive pneumococcal disease, of different degrees and timings. However, considerable progress in pneumococcal immunization over the last 30 years should benefit these patients. The 23-valent polysaccharide vaccine has been widely evaluated in these populations, but due to its low immunogenicity, its efficacy is sub-optimal, or even low. The principle of the conjugate vaccine is that, through the protein conjugation with the polysaccharide, the vaccine becomes more immunogenic, T-cell dependent, and thus providing a better early response and a boost effect. The 7-valent conjugate vaccine has been the first one to be evaluated in different immunocompromised populations. We review here the efficacy and safety of the different antipneumococcal vaccines in cancer, transplant and HIV-positive patients and propose a critical appraisal of the current guidelines.

Serologic response to primary vaccination with 7-valent pneumococcal conjugate vaccine is better than with 23-valent pneumococcal polysaccharide vaccine in HIV-infected patients in the era of combination antiretroviral therapy

OBJECTIVES

The objectives of this study were to compare the serologic responses at week 48 to primary vaccination with 23-valent pneumococcal polysaccharide vaccine (PPV) vs. 7-valent pneumococcal conjugate vaccine (PCV); and to identify factors associated with serologic response in HIV-infected adult patients with access to combination antiretroviral therapy (cART).

METHODS

One hundred and four CD4-matched pairs of HIV-infected patients who underwent primary pneumococcal vaccination with 23-valent PPV or 7-valent PCV were enrolled for determinations of anti-capsular antibody responses against four serotypes (6B, 14, 19F and 23F) at baseline, 24 weeks and 48 weeks following vaccination. Significant antibody responses were defined as 2-fold or greater increase of antibody levels at week 48 compared with baseline. The logistic regression model was used to determine the factors associated with serologic response to at least one and two serotypes.

RESULTS

At week 48, patients who received PCV demonstrated a statistically significantly higher response rate to at least 2 serotypes than those who received PPV (37.5% vs. 20.2%, p = 0.006). In multivariate analysis, factors associated with significant antibody responses to at least one or two serotypes included receipt of PCV (adjusted odds ratio [AOR], 2.42 [95% CI, 1.23-4.78] and 3.58 [95% CI. 1.76-7.28], respectively), and undetectable plasma HIV RNA load (< 400 copies/ml) at vaccination (AOR, 1.47 [95% CI, 0.60-3.64] and 3.62 [95% CI, 1.11-11.81], respectively).

CONCLUSIONS

Primary vaccination with 7-valent PCV achieved a significantly better serologic responses to one or two out of the four serotypes studied at week 48 than with 23-valent PPV in HIV-infected patients in the cART era. Suppression of HIV replication when primary vaccination was administered was associated with better serologic responses.

Pneumococcal polysaccharide 23-valent vaccine: long-term persistence of circulating antibody and immunogenicity and safety after revaccination in adults

Since publication of a 1997 review of the immunogenicity and safety data for pneumococcal polysaccharide vaccines (PPSVs), dozens of additional studies have been published, involving larger cohorts, longer observation periods, and more specific assays. Additionally, a 13-valent pneumococcal conjugate vaccine (PCV) has been licensed for adults. This paper reviews adult studies assessing antibody persistence for ≥ 3 years after pneumococcal vaccination, and adult studies of immunogenicity and safety after revaccination. This review emphasizes the currently registered PPSV23 formulations containing 25-μg polysaccharide per serotype, for which far more long-term data are available. Broadly, IgG and functional antibody levels after PPSV23 in adults persist above concentrations in unvaccinated adults for at least 5-10 years in most studies. The few exceptions involve populations of non-ambulatory adults or those with confounding host-factor issues. Revaccination with PPSV23 5-10 years after a previous dose consistently and substantially increases both IgG and functional antibody levels. There is an inverse association between circulating antibody level just before primary or revaccination and subsequent antibody increase. Although injection-site reactions (e.g., pain, swelling, redness) were reported more commonly after PPSV23 revaccination than after primary vaccination in most studies, these reactions typically resolved within 5 days. We interpret the contemporary literature as supporting pneumococcal revaccination as a means to sustain anti-pneumococcal antibodies at levels greater than among unvaccinated adults. PPSV23 is a broad-spectrum public-health tool to help prevent serious pneumococcal diseases across the adult lifespan.

Comparison of serologic responses to vaccination with one dose or two doses of 7-valent pneumococcal conjugate vaccine in HIV-infected adult patients

BACKGROUND

Vaccination with 7-valent pneumococcal conjugate vaccine (PCV) has been shown to decrease the incidence of recurrent invasive pneumococcal disease among HIV-infected adults in Africa. Longitudinal follow-up studies of serologic responses to different doses of 7-valent PCV are rarely performed in HIV-infected adult patients receiving combination antiretroviral therapy (cART).

METHODS

From October 2008 to June 2010, 115 CD4-matched pairs of HIV-infected patients aged ≥ 20 years who had no prior pneumococcal vaccination received one or two doses of 7-valent PCV. Anticapsular antibodies against 4 serotypes (6B, 14, 19F, and 23F) were examined at the 12th, 24th, 36th, and 48th week following vaccination. Significant antibody responses were defined as ≥ 2-fold increase in the IgG level plus a post-vaccination antibody level ≥ 1000 ng/ml.

RESULTS

The most common reported adverse effects were injection site soreness (19.3%) and pain (4.8%). Significant antibody response rate was highest for serotype 14, followed by 23F, 19F, and 6B in all of the four time points examined. At week 48, patients who received two doses of 7-valent PCV had a significantly higher response rate to serotype 6B (P=0.03) and 23F (P=0.01) than those who received one dose; moreover, the former group also had a higher response rate to at least one (P=0.03) and two serotypes (P=0.02) in intention-to-treat analysis than the latter group.

CONCLUSIONS

HIV-infected adult patients on cART who received two doses of 7-valent PCV achieved better serological responses to at least one serotype than those who received one dose during the 48 weeks of follow-up.

Cofactors that may influence vaccine responses

PURPOSE OF REVIEW

This review summarizes recent developments related to cofactors that may influence response to vaccination.

RECENT FINDINGS

The unexpected increased HIV acquisition among vaccinees in the Step trial with prior exposure to adenovirus type 5 (Ad5) led to several studies trying to understand whether an underlying biological risk factor may have been responsible for this observation. Demographic factors and genetic background of the human populations in HIV vaccine trials remain a source of potential variation in responses observed in vaccine trials, yet empirical data remain limited on the impact of those factors. Coinfections, particularly those that may modulate the immune response, are a further concern for HIV vaccine trialists, with recent data providing further insight into effects of coinfections on innate and adaptive immunity and vaccine responses.

SUMMARY

Individuals and human populations display variation in response to vaccination. Key explanatory variables for this variation include host factors, such as host genetics, and environmental factors, such as prior exposure to the vaccine vector, coinfection with other pathogens, and demographic factors. This review will outline some of the recent developments investigating the role of various cofactors on vaccine responses, with a particular emphasis on studies of HIV vaccines.