From Qualitative Research to Quantitative Preference Elicitation: An Example in Invasive Meningococcal Disease

BACKGROUND

Qualitative research is fundamental for designing discrete choice experiments (DCEs) but is often underreported in the preference literature. We developed a DCE to elicit preferences for vaccination against invasive meningococcal disease (IMD) among adolescents and young people (AYP) and parents and legal guardians (PLG) in the United States. This article reports the targeted literature review and qualitative interviews that informed the DCE design and demonstrates how to apply the recent reporting guidelines for qualitative developmental work in preference studies.

METHODS

This study included two parts: a targeted literature review and qualitative interviews. The Medline and Embase databases were searched for quantitative and qualitative studies on IMD and immunization. The results of the targeted literature review informed a qualitative interview guide. Sixty-minute, online, semi-structured interviews with AYP and PLG were used to identify themes related to willingness to be vaccinated against IMD. Participants were recruited through a third-party recruiter's database and commercial online panels. Interviews included vignettes about IMD and vaccinations and three thresholding exercises examining the effect of incidence rate, disability rate, and fatality rate on vaccination preferences. Participant responses related to the themes were counted.

RESULTS

The targeted literature review identified 31 concepts that were synthesized into six topics for the qualitative interviews. Twenty AYP aged 16-23 years and 20 PLG of adolescents aged 11-17 years were interviewed. Four themes related to willingness to be vaccinated emerged: attitudes towards vaccination, knowledge and information, perception of IMD, and vaccine attributes. Most participants were concerned about IMD (AYP 60%; PLG 85%) and had positive views of vaccination (AYP 80%; PLG 60%). Ninety percent of AYP and 75% of PLG always chose vaccination over no vaccination, independent of IMD incidence rate, disability rate, or fatality rate.

CONCLUSION

Willingness to be vaccinated against IMD was affected by vaccine attributes but largely insensitive to IMD incidence and severity. This article provides an example of how to apply the recent reporting guidelines for qualitative developmental work in preference studies, with 21 out of 22 items in the guidelines being considered.

Epidemiology of Pneumococcal Pneumonia in Louisville, Kentucky, and Its Estimated Burden of Disease in the United States

Streptococcus pneumoniae remains a primary pathogen in hospitalized patients with community-acquired pneumonia (CAP). The objective of this study was to define the epidemiology of pneumococcal pneumonia in Louisville, Kentucky, and to estimate the burden of pneumococcal pneumonia in the United States (US). This study was nested in a prospective population-based cohort study of all adult residents in Louisville, Kentucky, who were hospitalized with CAP from 1 June 2014 to 31 May 2016. In hospitalized patients with CAP, urinary antigen detection of 24 S. pneumoniae serotypes (UAD-24) was performed. The annual population-based pneumococcal pneumonia incidence was calculated. The distribution of S. pneumoniae serotypes was characterized. Ecological associations between pneumococcal pneumonia and income level, race, and age were defined. Mortality was evaluated during hospitalization and at 30 days, 6 months, and 1 year after hospitalization. Among the 5402 CAP patients with a UAD-24 test performed, 708 (13%) patients had pneumococcal pneumonia. The annual cumulative incidence was 93 pneumococcal pneumonia hospitalizations per 100,000 adults (95% CI = 91-95), corresponding to an estimated 226,696 annual pneumococcal pneumonia hospitalizations in the US. The most frequent serotypes were 19A (12%), 3 (11%), and 22F (11%). Clusters of cases were found in areas with low incomes and a higher proportion of Black or African American population. Pneumococcal pneumonia mortality was 3.7% during hospitalization, 8.2% at 30 days, 17.6% at 6 months, and 25.4% at 1 year after hospitalization. The burden of pneumococcal pneumonia in the US remains significant, with an estimate of more than 225,000 adults hospitalized annually, and approximately 1 out of 4 hospitalized adult patients dies within 1 year after hospitalization.

Diagnosis of Respiratory Syncytial Virus in Adults Substantially Increases When Adding Sputum, Saliva, and Serology Testing to Nasopharyngeal Swab RT-PCR

INTRODUCTION

Nearly all existing respiratory syncytial virus (RSV) incidence estimates are based on real-time polymerase chain reaction (RT-PCR) testing of nasal or nasopharyngeal (NP) swabs. Adding testing of additional specimen types to NP swab RT-PCR increases RSV detection. However, prior studies only made pairwise comparisons and the synergistic effect of adding multiple specimen types has not been quantified. We compared RSV diagnosis by NP swab RT-PCR alone versus NP swab plus saliva, sputum, and serology.

METHODS

This was a prospective cohort study over two study periods (27 December 2021 to 1 April 2022 and 22 August 2022 to 11 November 2022) of patients aged ≥ 40 years hospitalized for acute respiratory illness (ARI) in Louisville, KY. NP swab, saliva, and sputum specimens were collected at enrollment and PCR tested (Luminex ARIES platform). Serology specimens were obtained at acute and convalescent timepoints (enrollment and 30-60-day visit). RSV detection rate was calculated for NP swab alone and for NP swab plus all other specimen type/test.

RESULTS

Among 1766 patients enrolled, 100% had NP swab, 99% saliva, 34% sputum, and 21% paired serology specimens. RSV was diagnosed in 56 (3.2%) patients by NP swab alone, and in 109 (6.2%) patients by NP swab plus additional specimens, corresponding to a 1.95 times higher rate [95% confidence interval (CI) 1.62, 2.34]. Limiting the comparison to the 150 subjects with all four specimen types available (i.e., NP swab, saliva, sputum, and serology), there was a 2.60-fold increase (95% CI 1.31, 5.17) compared to NP swab alone (3.3% versus 8.7%). Sensitivities by specimen type were: NP swab 51%, saliva 70%, sputum 72%, and serology 79%.

CONCLUSIONS

Diagnosis of RSV in adults was several-fold greater when additional specimen types were added to NP swab, even with a relatively low percentage of subjects with sputum and serology results available. Hospitalized RSV ARI burden estimates in adults based solely on NP swab RT-PCR should be adjusted for underestimation.

Modeling persistence of hSBA titers over time following a primary series and a booster dose of MenB-FHbp

MenB-FHbp is a meningococcal serogroup B vaccine. Persistence of hSBA titers against 4 diverse test strains ≤ 4 years after a 2-dose MenB-FHbp primary series and ≤ 26 months after a booster dose administered 4 years post-primary has been demonstrated. Here, we developed a power law model (PLM) to estimate the persistence of hSBA titers up to 5 years after a MenB-FHbp primary series and a booster dose using hSBA data from previous MenB-FHbp clinical trials in healthy adolescents. The PLM-predicted hSBA titers closely followed observed values after a 0, 6 month MenB-FHbp primary series and a booster dose 4 years later. At 5 years post-primary and 5 years post-booster, the PLM predicted that 15.2 %-50.0 % and 51.2 %-70.9 % of individuals, respectively, would have hSBA titers ≥ 1:8 or 1:16. The PLM supports that the persistence of hSBA titers is maintained for at least 5 years post-primary MenB-FHbp vaccination and post-booster.

A phase 3, randomized, controlled, open-label study to evaluate the persistence up to 5 years of 1 or 2 doses of meningococcal conjugate vaccine MenACWY-TT given with or without 13-valent pneumococcal conjugate vaccine in 12-14-month-old children

BACKGROUND

Immunogenicity and safety up to 5 years after administration of 1 or 2 doses of quadrivalent meningococcal serogroup A, C, W, and Y tetanus toxoid conjugate vaccine (MenACWY-TT) given alone or with 13-valent pneumococcal conjugate vaccine (PCV13) in children was investigated.

METHODS

This phase 3 study randomized healthy 12-24-month-olds to MenACWY-TT at Month 0 (ACWY1d), MenACWY-TT at Months 0 and 2 (ACWY2d), MenACWY-TT and PCV13 at Month 0 (Co-Ad), or PCV13 at Month 0 and MenACWY-TT at Month 2 (PCV13/ACWY). Immune responses 1, 3, and 5 years after primary vaccination were evaluated with serum bactericidal activity using rabbit complement (rSBA) titers ≥ 1:8 and geometric mean titers (GMTs). Evaluation of serious adverse events up to 5 years after primary vaccination are reported.

RESULTS

Of the 802 children randomized in the study, 619 completed the study through Year 5. Immune responses after vaccination declined over time but were higher 5 years after vaccination compared with levels before vaccination. At Year 5, the percentages of children with rSBA titers ≥ 1:8 across all serogroups were 20.5 %-58.6 %, 28.4 %-65.8 %, 23.9 %-52.8 %, and 19.4 %-55.8 % in the ACWY1d, ACWY2d, Co-Ad, and PCV13/ACWY groups, respectively. Comparable antibody persistence at Year 5 was observed for participants receiving 1 or 2 doses of MenACWY-TT, although GMTs were elevated in those who received 2 versus 1 dose. The percentage of children with protective antibody titers at Year 5 was similar in participants who received PCV13 and MenACWY-TT compared with that observed for participants who only received 1 or 2 MenACWY-TT doses. No new safety concerns were identified during the study period.

CONCLUSION

Antibody responses persisted in the majority of children up to 5 years after primary vaccination with MenACWY-TT administered in a 1- or 2-dose regimen with or without PCV13, with no new safety concerns identified.

CLINICALTRIALS

gov Identifier NCT01939158; EudraCT number 2013-001083-28.

371. Adding sputum and saliva to nasopharyngeal swab samples for PCR detection of Respiratory Syncytial Virus in adults hospitalized with acute respiratory illness may double case detection

Background

In hospitalized patients, nasopharyngeal (NP) swabs are the most common samples obtained for Respiratory Syncytial Virus (RSV) PCR testing. However, adding sputum is known to increase diagnostic yield, and saliva has been successfully used for viral respiratory infection diagnosis. We sought to compare RSV prevalence detected by PCR testing of NP swab alone versus NP swab plus saliva and sputum in adult patients hospitalized with acute respiratory illness (ARI).

Methods

This ongoing, prospective cohort study enrolled patients aged ≥40 years hospitalized for ARI in 4 hospitals in Louisville, Kentucky (Season 1: 27 Dec 21 – 1 Apr 22). NP swab, saliva, and sputum samples were obtained at enrollment or scavenged from standard-of-care specimens (all collected ≤3 days of admission), and PCR tested with Luminex ARIES FluA/B/RSV platform. We produced Venn diagrams of RSV positive samples by sample type for all patients and restricted to those with all 3 sample types. RSV prevalence for NP swab alone was calculated as number of patients with RSV-positive NP swabs divided by total number of patients tested. RSV prevalence by NP swab plus saliva and sputum was calculated as number of patients with RSV-positive NP swab, saliva, or sputum samples divided by total number of patients tested.

Results

We enrolled 653 patients and collected NP swabs (100% of patients), saliva (96%), and sputum (43% overall and 93% of the 303 sputum-producing patients). Among all patients, 28 patients tested RSV positive (Figure 1A), and when restricted to those with all 3 samples (Figure 1B), 14 tested positive. The overall cohort’s RSV prevalence by NP swab alone was 1.8% (12/653) and by NP swab plus saliva and/or sputum was 4.3% (28/653): 2.33 times higher with addition of saliva and sputum samples. Among patients with all 3 specimen types, the RSV prevalence increase was the same, and none were positive by NP swab only. Figure 1.

Rationale for the Development of a Pentavalent Meningococcal Vaccine: A US-Focused Review

While invasive meningococcal disease (IMD) is uncommon, it can result in serious sequelae and even death. In 2018 in the United States, the incidence of IMD per 100,000 people was 0.03 among adolescents 11−15 years of age, 0.10 among persons 16−23 years of age, and 0.83 among infants < 1 year of age. Serogroup B accounted for 86%, 62%, and 66% of cases, respectively, in those age groups. Currently, routine meningococcal vaccination covering serogroups ACWY (MenACWY) is recommended in the United States for all adolescents at 11−12 years of age, with a booster dose at 16 years of age, whereas a meningococcal serogroup B (MenB) vaccine series is recommended for persons 16−23 years of age under the shared clinical decision-making paradigm. The MenACWY vaccination program in adolescents has been successful in reducing disease burden, but does not prevent disease caused by serogroup B, which accounts for more than half of IMD cases. There are currently no approved vaccines that cover all of the most common disease-causing meningococcal serogroups, which are A, B, C, W, and Y. A pentavalent MenABCWY vaccine that is constituted from 2 licensed meningococcal vaccines—MenB-FHbp and MenACWY-TT—is being investigated in healthy persons ≥ 10–25 years of age. The addition of a MenABCWY vaccine is the next natural step in the incremental meningococcal immunization program in the United States to improve protection against the most common serogroup causing IMD, with no increase in the number of immunizations needed. With high uptake, routine use of MenABCWY could reduce IMD cases and associated mortality, the rate of long-term physical and psychosocial sequelae in survivors, and costs associated with controlling outbreaks, particularly on college campuses. A MenABCWY vaccine would also reduce the number of injections required for adolescents, potentially improving compliance.

Safety data from the MenB-FHbp clinical development program in healthy individuals aged 10 years and older

BACKGROUND

The MenB-FHbp vaccine (Trumenba®) is licensed in various countries for the prevention of meningococcal serogroup B disease in individuals ≥ 10 years of age. The clinical development program included 11 completed trials where, in each trial, MenB-FHbp had an acceptable safety profile after a primary vaccination series was administered to individuals 10-65 years of age. However, the detection of potential rare events was limited because of individual clinical trial size. The current safety analysis evaluates pooled reactogenicity and other adverse events (AEs) reported in these trials to identify new safety signals not detectable in individual trials.

METHODS

Eleven trials contributed safety data, of which 10 recorded local and systemic reactogenicity events; 8 of the trials were controlled, and reactogenicity data were pooled for 7 of these 8 trials. Additional AE evaluations included immediate AEs (IAEs), medically attended AEs (MAEs), serious AEs (SAEs), newly diagnosed chronic medical conditions (NDCMCs), and autoimmune or neuroinflammatory conditions.

RESULTS

Local and systemic reactions were more frequent in the MenB-FHbp group (n = 15,294) compared with controls (n = 5509), although most reactions were transient and mild to moderate in severity. Frequencies of IAEs, SAEs, MAEs, NDCMCs, and autoimmune or neuroinflammatory conditions were similar between the MenB-FHbp and control groups.

CONCLUSIONS

MenB-FHbp demonstrated a favorable safety and tolerability profile in the clinical development program of > 15,000 vaccine recipients ≥ 10 years of age. No new safety signals were identified in the pooled analysis compared with data from the individual trials. Continued postmarketing safety surveillance is important for the identification of rare events. Clinicaltrials.gov: NCT01299480; NCT000808028; NCT00879814; NCT00780806; NCT01352845; NCT01352793; NCT01461993; NCT01323270; NCT01830855; NCT01461980; NCT01768117.

A phase 3, randomized, double-blind study to evaluate the immunogenicity and safety of 3 lots of 20-valent pneumococcal conjugate vaccine in pneumococcal vaccine-naive adults 18 through 49 years of age

INTRODUCTION

Introduction of pneumococcal conjugate vaccines (PCVs), including the 13-valent PCV (PCV13), has considerably reduced pneumococcal disease burden. However, additional serotypes not in PCV13 continue to present a substantial disease burden. The 20-valent PCV (PCV20) was developed to expand protection against pneumococcal disease beyond PCV13. As part of the phase 3 clinical development program, the current study assessed consistency of immune responses across 3 lots of PCV20 and described the safety profile of PCV20.

METHODS

This phase 3, randomized, multicenter, double-blind study of pneumococcal vaccine-naive adults 18-49 years of age randomized 1710 participants in a 2:2:2:1 ratio to receive 1 of 3 lots of PCV20 or PCV13. Immunogenicity was assessed through serotype-specific opsonophagocytic activity (OPA) titers before and approximately 1 month (28-42 days) after vaccination. Reported local reactions within 10 days, systemic events within 7 days, adverse events (AEs) within 30 days, and serious AEs (SAEs) and newly diagnosed chronic medical conditions (NDCMCs) within 6 months after vaccination were evaluated.

RESULTS

Equivalence in immune responses (OPA geometric mean titers) for all 20 vaccine serotypes was demonstrated across the 3 PCV20 lots. Robust responses, assessed by OPA geometric mean fold rises, percentage of participants achieving ≥4-fold rises, and percentage of participants with OPA titers ≥lower limit of quantitation, were observed after PCV20. Reported rates of local reactions, systemic events, and AEs were similar between the pooled PCV20 lots and PCV13; most events were mild or moderate. Reported rates of SAEs and NDCMCs were low and similar between the PCV20 and PCV13 groups.

CONCLUSIONS

Three different lots of PCV20 demonstrated robust and consistent immunogenicity. The safety and tolerability of PCV20 was acceptable and similar to that of PCV13. (Clinicaltrials.gov: NCT03828617).

Ten-Year Antibody Persistence and Booster Response to MenACWY-TT Vaccine After Primary Vaccination at 1-10 Years of Age

This phase 3B, open-label, extension study (NCT01962207) evaluated long-term persistence of antibodies induced by the quadrivalent meningococcal vaccine conjugated to tetanus toxoid (MenACWY-TT) compared with the meningococcal serogroup C vaccine conjugated to CRM (MenC-CRM) and the quadrivalent meningococcal polysaccharide vaccine (MenACWY-PS) 6 to 10 y after primary vaccination in toddlers (aged 1–<2 y; MenACWY-TT and MenC-CRM) and children (aged 2–<11 y; MenACWY-TT and MenACWY-PS). Antibody responses against meningococcal serogroups A, C, W, and Y were assessed by serum bactericidal antibody assays using rabbit (rSBA) or human (hSBA) complement. A MenACWY-TT booster dose at Year 10 was given to all eligible subjects regardless of the primary vaccine received. At Year 10, the percentages of subjects with rSBA titers ≥1:8 for serogroups A, C, W, and Y were as follows: MenACWY-TT (toddlers), 65.6%, 82.8%, 31.3%, 43.8%, respectively; MenC-CRM, 88.2% for serogroup C; MenACWY-TT (children), 88.9%, 84.1%, 67.1%, 65.9%; and MenACWY-PS, 28.6%, 81.0%, 23.8%, and 23.8%. Corresponding percentages for hSBA titers ≥1:4 were as follows: MenACWY-TT (toddlers), 31.1%, 91.9%, 44.4%, 41.4%; MenC-CRM, 93.8% for serogroup C; MenACWY-TT (children), 34.8%, 91.1%, 61.2%, 72.6%; and MenACWY-PS, 33.3%, 100.0%, 26.3%, and 44.4%. One month after the MenACWY-TT booster, the percentage of subjects with vaccine response ranged from 75.7% to 100.0% across serogroups in all study groups. Postbooster vaccine responses were generally comparable between groups across serogroups. No new safety signals were identified. Antibody responses persisted 10 y after MenACWY-TT vaccination. The MenACWY-TT booster dose was well tolerated and elicited robust immune responses.

Expanded Analysis of 20 Pneumococcal Serotypes Associated With Radiographically Confirmed Community-Acquired Pneumonia in Hospitalized US Adults

Background

Streptococcus pneumoniae is a causative agent of community-acquired pneumonia (CAP). The 13-valent pneumococcal conjugate vaccine (PCV13) has significantly decreased the burden of PCV13-serotype pneumococcal disease; however, disease from nonvaccine serotypes remains substantial. A recent study documented the persistence of PCV13 serotypes among US adults hospitalized with radiographically confirmed CAP. The current analysis used a recently developed urinary antigen detection (UAD) assay (UAD2) to extend these results to additional serotypes included in an investigational PCV20 vaccine.

Methods

This prospective study enrolled adults aged ≥18 years hospitalized with radiographically confirmed CAP between October 2013 and September 2016. Presence of S pneumoniae was determined by blood and respiratory sample culture, BinaxNOW urine testing, and UAD. In addition to Quellung on cultured isolates when available, serotypes were identified from urine specimens using UAD1 for PCV13 serotypes and UAD2 for 7 PCV20-unique serotypes (8, 10A, 11A, 12F, 15B, 22F, and 33F) and 4 additional serotypes (2, 9N, 17F, and 20).

Results

Among 12 055 subjects with radiographically confirmed CAP, 1482 were positive for S pneumoniae. PCV13- and PCV20-unique serotypes were associated with 37.7% (n = 559) and 27.0% (n = 400) of cases, respectively; 288 subjects were exclusively diagnosed as positive for S pneumoniae by UAD2. Demographic and clinical disease characteristics were similar between subjects with CAP caused by PCV13 and PCV20-unique serotypes.

Conclusions

The current analysis using UAD2 identified a sizeable proportion of hospitalized adult CAP associated with PCV20-unique serotypes. PCV20 may therefore address the burden of CAP caused by the additional serotypes present in the vaccine.

Epigenetic Mechanisms Underlying HIV-Infection Induced Susceptibility of CD4+ T Cells to Enhanced Activation-Induced FasL Expression and Cell Death

BACKGROUND

Chronic immune activation and CD4 T cell depletion are significant pathogenic features of HIV infection. Expression of Fas ligand (FasL), a key mediator of activation-induced cell death in T cells, is elevated in people living with HIV-1 infection (PLWH). However, the epigenetic mechanisms underlying the enhanced induction of FasL expression in CD4 T lymphocytes in PLWH are not completely elucidated. Hence, the current work examined the effect of HIV infection on FasL promoter-associated histone modifications and transcriptional regulation in CD4 T lymphocytes in PLWH.

METHOD

Flow cytometric analysis was performed to examine the Fas-FasL expression on total CD4 T cells and naïve/memory CD4 T cell subsets. Epigenetic FasL promoter histone modifications were investigated by chromatin immunoprecipitation-quantitative real-time polymerase chain reaction analysis using freshly isolated total CD4 T lymphocytes from HIV-1 infected and noninfected individuals.

RESULTS

All naïve/memory CD4 T cell subsets from PLWH showed markedly greater frequency of FasL expression. Notably, examination of functional outcome of FasL/Fas co-expression demonstrated the preferential susceptibility of Tcm and Tem subsets to activation-induced apoptosis. Importantly, these CD4 T cells collectively demonstrated a distinct FasL promoter histone profile involving a coordinated cross-talk between histone H3 modifications leading to enhanced FasL gene expression. Specifically, levels of transcriptionally permissive histone H3K4-trimethylation (H3K4Me3) and histone H3K9-acetylation (H3K9Ac) were increased, with a concomitant decrease in the repressive H3K9-trimethylation (H3K9Me3).

CONCLUSION

The present work demonstrates that epigenetic mechanisms involving promoter-histone modifications regulate transcriptional competence and FasL expression in CD4 T cells from PLWH and render them susceptible to activation-induced cell death.

3. A Review of the Clinical Development of MenACWY-TT, a Quadrivalent Meningococcal Vaccine Conjugated to Tetanus Toxoid, in Adolescents

Background

As a peak in meningococcal disease often occurs during adolescence, meningococcal vaccination programs are available for this age group in various regions across the globe. Quadrivalent meningococcal (MenACWY) conjugate vaccines are being incorporated in an increasing number of programs in response to changing meningococcal serogroup epidemiology. MenACWY-TT (Nimenrix®) is a MenACWY conjugate vaccine available in the European Union and 50 other countries for preventive vaccination of serogroup A, C, W, and Y disease (Figure 1). MenACWY-TT is licensed in some countries as a 2-dose primary series in individuals as young as 6 weeks of age, while a single dose may be given to previously unvaccinated individuals ≥ 6 months of age, adolescents, and adults. Here, we provide an overview of the 3 primary and 5 extension studies evaluating the clinical development of MenACWY-TT in adolescents (Table 1).

Figure 1. Global Registration Status of MenACWY-TT (Nimenrix®) in Adolescents

Table 1. Pivotal Clinical Studies of MenACWY-TT (Nimenrix®) Supporting Licensure in Adolescents

Methods

Immunogenicity and safety data from these 8 clinical studies are summarized.

Results

Across studies, MenACWY-TT antibody responses against all vaccine serogroups were comparable to those of other MenACWY vaccines 1 month post vaccination (Table 1). Antibody responses to MenACWY-TT persisted for up to 10 years in those vaccinated during adolescence. A MenACWY-TT booster given 10 years after primary meningococcal vaccination in early childhood or adolescence elicited robust antibody responses. MenACWY-TT had an acceptable safety profile, with reactogenicity events most commonly reported. Reactogenicity profiles with MenACWY-TT booster were similar to those seen after primary MenACWY-TT.

Conclusion

The MenACWY-TT clinical study program demonstrated the immunogenicity and safety of primary and booster dosing in adolescents. Immune responses persisted through 10 years after primary vaccination.

Funding

Pfizer.

Disclosures

Paula Peyrani, MD, Pfizer Inc (Employee, Shareholder) Chris Webber, MD, Pfizer Inc (Employee, Shareholder) Cindy Burman, PharmD, Pfizer Inc (Employee, Shareholder) Paul Balmer, PhD, Pfizer Inc (Employee, Shareholder) John L. Perez, MD, MA, Pfizer Inc (Employee, Shareholder)

4. MenACWY-TT Long-Term Antibody Persistence Following Adolescent Vaccination and Evaluation of a Booster Dose: A Review of Clinical Data

Background

A peak in meningococcal carriage and invasive meningococcal disease (IMD) occurs during adolescence and young adulthood. In the United States, preventive vaccination with a quadrivalent meningococcal (MenACWY) conjugate vaccine is recommended at age 11–12 years, with a booster dose given at age 16 years. MenACWY-TT (Nimenrix®), a MenACWY tetanus toxoid conjugate vaccine, was first licensed in 2012 and is available in the European Union and 50 other countries. Immune responses to other MenACWY conjugate vaccines decline over several years following vaccination. Here, we review 2 recent studies evaluating the long-term persistence of MenACWY-TT immune responses in adolescents as well as safety and immunogenicity of a booster dose given 10 years after primary vaccination.

Methods

Both studies (ClinicalTrials.gov NCT01934140, NCT03189745) were extensions of phase 2 or 3 studies of subjects 11–17 years of age given a single dose of MenACWY-TT or MenACWY polysaccharide vaccine (MenACWY-PS). Immune responses through 10 years after primary vaccination and after a Year 10 MenACWY-TT booster dose were measured by serum bactericidal antibody assays using baby rabbit complement (rSBA). Specific endpoints included percentages of subjects with rSBA titers ≥1:8 and ≥1:128 and geometric mean titers (GMTs). Booster dose safety and tolerability were also evaluated.

Results

In both studies, the percentages of subjects with rSBA titers ≥1:8 through 10 years postvaccination were generally higher or similar among MenACWY-TT (69.3%–91.2% at Year 10; n=137–163) compared with MenACWY-PS (24.4%–88.9%; n=45–53) recipients for all 4 serogroups (Figure); similar results were observed for GMTs (146.0–446.9 vs 12.9–191.0 at Year 10). One month after a MenACWY-TT booster dose, 97.7%–100% of subjects across groups had titers ≥1:8 (Figure), and GMTs were markedly higher than prebooster values. No new safety signals were identified following the booster dose.

Figure 1. Subjects in each of the 2 studies with rSBA titers ≥1:8 before and at 1 month, 5 years, and 10 years after primary vaccination with MenACWY-TT or MenACWY-PS at 11–17 years of age and 1 month after booster vaccination with MenACWY-TT at 10 years following primary vaccination.

Conclusion

Functional antibodies for all 4 serogroups persisted through 10 years after MenACWY-TT adolescent vaccination, suggesting that this vaccine may help prevent IMD throughout the lengthy risk period in this group. A MenACWY-TT booster dose may further extend protection regardless of the primary vaccine received.

Funded by Pfizer.

Disclosures

Paula Peyrani, MD, Pfizer Inc (Employee, Shareholder) Chris Webber, MD, Pfizer Inc (Employee, Shareholder) Cindy Burman, PharmD, Pfizer Inc (Employee, Shareholder) Paul Balmer, PhD, Pfizer Inc (Employee, Shareholder) John L. Perez, MD, MA, Pfizer Inc (Employee, Shareholder)

A phase 2b/3b MenACWY-TT study of long-term antibody persistence after primary vaccination and immunogenicity and safety of a booster dose in individuals aged 11 through 55 years

BACKGROUND

A previous phase 2 study demonstrated the immunogenicity of a single dose of meningococcal A, C, W, Y-tetanus toxoid conjugate (MenACWY-TT) or polysaccharide (MenACWY-PS) vaccine for up to 5 years in individuals aged 11-55 years. This follow-up study evaluated long-term antibody persistence up to 10 years and the immunogenicity and safety of a single MenACWY-TT booster dose given 10 years after primary vaccination.

METHODS

Blood draws were conducted annually in Years 7-10. At Year 10, all subjects received a MenACWY-TT booster dose. Blood was drawn at 1 month and safety data were collected ≤6 months postbooster. Study endpoints included immunogenicity during the persistence phase (primary), and immunogenicity and safety during the booster phase (secondary). Statistical analyses were descriptive.

RESULTS

A total of 311 subjects were enrolled in the persistence phase (MenACWY-TT, 235; MenACWY-PS, 76); 220 were enrolled in the booster phase (MenACWY-TT, 164; MenACWY-PS, 56). Descriptive analyses indicated that at Years 7-10, the percentages of subjects achieving serum bactericidal antibody assay using baby rabbit complement (rSBA) titers ≥1:8 and ≥1:128 were higher for serogroups A, W, and Y in the MenACWY-TT versus MenACWY-PS group; percentages were similar across groups for serogroup C. rSBA geometric mean titers (GMTs) for serogroups A, W, and Y were higher in the MenACWY-TT group and slightly higher in the MenACWY-PS group for serogroup C. One month postbooster, all primary MenACWY-TT and ≥98.1% of primary MenACWY-PS recipients had rSBA titers ≥1:8. For all serogroups, rSBA GMTs postbooster were higher in the MenACWY-TT versus MenACWY-PS group. Most local and general reactogenicity events were similar between groups and mild to moderate in severity. Adverse events at 1 month postbooster were 9.1% for the MenACWY-TT and 3.6% for the MenACWY-PS groups; all were nonserious.

CONCLUSIONS

Immune responses to a single MenACWY-TT primary dose administered at age 11-55 years persisted in >70% of individuals evaluated at Years 7-10. A MenACWY-TT booster dose administered at Year 10 was safe and immunogenic with no new safety signals observed. These results provide important insights regarding long-term protection from primary vaccination and the benefits of booster dosing.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT01934140. Registered September 2013.

Efficacy and safety of a booster dose of the meningococcal A, C, W, Y-tetanus toxoid conjugate vaccine administered 10 years after primary vaccination and long-term persistence of tetanus toxoid conjugate or polysaccharide vaccine

A previous phase 3, randomized, multicenter study showed the immunogenicity of a primary vaccination of subjects aged 11 to 17 years with the quadrivalent meningococcal vaccine conjugated to tetanus toxoid (MenACWY-TT) or the quadrivalent meningococcal polysaccharide vaccine (MenACWY-PS). This extension study evaluated the safety and immunogenicity of a MenACWY-TT booster 10 years after receiving a primary dose of either MenACWY-TT or MenACWY-PS. The primary immunogenicity endpoint was booster response, evaluated using serum bactericidal antibody assays with rabbit complement (rSBA), 1 month postbooster. Safety endpoints included the percentage of subjects experiencing local and general adverse events (AEs) ≤4 days after MenACWY-TT booster. Of 229 subjects enrolled, 169 and 58 in the MenACWY-TT and MenACWY-PS groups, respectively, completed the booster phase. The 1 month postbooster response for each serogroup ranged from 81.5% to 95.7% for MenACWY-TT and 66.7% to 94.1% for MenACWY-PS. Similar percentages of MenACWY-TT and MenACWY-PS recipients had a booster response to serogroups A, W, and Y, whereas more MenACWY-TT recipients than MenACWY-PS recipients had a booster response to serogroup C. For the MenACWY-TT and MenACWY-PS groups, respectively, the MenACWY-TT booster elicited rSBA titers ≥1:8 in 100% and ≥98.0% of subjects across all serogroups; 100% and ≥96.1% of all subjects had titers ≥1:128. No new safety signals were observed during the booster phase. In conclusion, a MenACWY-TT booster dose after receiving either a primary dose of MenACWY-TT or MenACWY-PS elicited robust immune responses and was well tolerated. Functional antibody responses last up to 10 years after primary MenACWY-TT vaccination.

Persistence of bactericidal antibodies following primary and booster MenACWY-TT vaccination of toddlers: A review of clinical studies

The long-term persistence of antibody responses following primary vaccination with quadrivalent conjugate vaccines targeting meningococcal serogroups A, C, W, and Y (MenACWY) and the duration of protection following a booster dose have not been fully elucidated, particularly in children who received primary dosing as toddlers. This review summarizes the findings of one phase 3 and three phase 2 open-label, randomized clinical studies that assessed the long-term antibody persistence of MenACWY conjugated to tetanus toxoid as a carrier protein (MenACWY-TT) in toddlers. Following primary vaccination, antibody responses persisted for approximately 2-3 years and then decreased up to 5 years after vaccination. Geometric mean titers remained elevated for all serogroups up to 5 years after primary vaccination. In children who received a booster dose of MenACWY-TT at 4-5 years after primary dosing as toddlers, antibody responses were documented in >99% of subjects across all serogroups, with minimal decreases in antibody persistence from 2-6 years after booster vaccination. The persistence of meningococcal serogroup C (MenC) antibody responses was similar between MenACWY-TT and MenC vaccine recipients after primary and booster dosing. Together, these findings indicate that antibody responses to primary MenACWY-TT vaccination persist for 2-3 years. Additionally, these findings indicate that in subjects who receive primary MenACWY-TT vaccination as toddlers, the antibody response to booster MenACWY-TT vaccination lasts for up to 6 years and suggest that immune memory is afforded at least into early adolescence, which is an age group at increased risk of invasive meningococcal disease.

Socioeconomic Position and the Incidence, Severity, and Clinical Outcomes of Hospitalized Patients With Community-Acquired Pneumonia

OBJECTIVES

The influence of socioeconomic disparities on adults with pneumonia is not well understood. The objective of our study was to evaluate the relationship between community-level socioeconomic position, as measured by an area deprivation index, and the incidence, severity, and outcomes among adults with community-acquired pneumonia (CAP).

METHODS

This was an ancillary study of a population-based, prospective cohort study of patients hospitalized with CAP in Louisville, Kentucky, from June 1, 2013, through May 31, 2015. We used a race-specific, block group-level area deprivation index as a proxy for community-level socioeconomic position and evaluated it as a predictor of CAP incidence, CAP severity, early clinical improvement, 30-day mortality, and 1-year mortality.

RESULTS

The cohort comprised 6349 unique adults hospitalized with CAP. CAP incidence per 100 000 population increased significantly with increasing levels of area deprivation, from 303 in tertile 1 (low deprivation), to 467 in tertile 2 (medium deprivation), and 553 in tertile 3 (high deprivation) (P < .001). Adults in medium- and high-deprivation areas had significantly higher odds of severe CAP (tertile 2 odds ratio [OR] = 1.2 [95% confidence interval (CI), 1.06-1.39]; tertile 3 OR = 1.4 [95% CI, 1.18-1.64] and 1-year mortality (tertile 2 OR = 1.3 [95% CI, 1.11-1.54], tertile 3 OR = 1.3 [95% CI, 1.10-1.64]) than adults in low-deprivation areas.

CONCLUSIONS

Compared with adults residing in low-deprivation areas, adults residing in high-deprivation areas had an increased incidence of CAP, and they were more likely to have severe CAP. Beyond 30 days of care, we identified an increased long-term mortality for persons in high-deprivation areas. Community-level socioeconomic position should be considered an important factor for research in CAP and policy decisions.

Burden of Adults Hospitalized with Group B Streptococcal Infection

Background

The burden of noninvasive group B Streptococcus (GBS) infections in adults is unknown. We determined population-based rates of hospitalization where invasive or noninvasive GBS infections were identified among US adults in a defined catchment area.

Methods

We identified adults with clinical and laboratory-confirmed evidence of GBS infection from January 2014 through December 2016 from 6 hospitals in Louisville, Kentucky. Invasive disease was defined as GBS isolated from a normally sterile site.

Results

Among 1076 adults with GBS infection, the median age was 52 years, 51% were male, and 89% had ≥1 chronic medical condition. The most prevalent infection sites were skin and soft tissue (39%), urinary tract (23%), bone and joint (16%), and bloodstream (11%). Forty percent of infections were polymicrobial. The annual incidence of GBS-associated hospitalization was 73 per 100 000 adults and 68 and 100 per 100 000 for patients aged 18–64 and ≥ 65 years, respectively. For every invasive GBS infection, 3.7 noninvasive infections occurred.

Conclusions

Our population-based study outlines the full burden of GBS-associated hospitalization in adults and found incidence rates comparable to those of pneumococcal disease, where vaccines are recommended. Noninvasive disease was 3–4 times more common than invasive disease, suggesting that the GBS burden among adults is considerably greater than previously recognized.

The elevated systemic cytokine levels in HIV patients are not associated with an elevated pulmonary cytokine environment

BACKGROUND

HIV-positive patients on anti-retroviral therapy (ART) are at higher risk of developing many non-AIDS related chronic diseases, including chronic obstructive pulmonary disease (COPD), compared to HIV-negative individuals. While the mechanisms are not clear, a persistent pro-inflammatory state appears to be a key contributing factor. The aims of this study were to investigate whether HIV-positive patients without COPD present evidence of potentially predisposing abnormal pulmonary cytokine/chemokine environment and to explore the relationship between pulmonary and systemic cytokine levels.

METHODS

This study included 39 HIV-seropositive and 34 HIV-seronegative subjects without COPD. All were subjected to outpatient bronchoscopy with bronchoalveolar lavage fluid (BALF) aspiration and blood sample collection. The levels of 21 cytokines and chemokines were measured in plasma and BALF using a bead-based multi-analyte assay.

RESULTS

In plasma, HIV-infected patients showed significantly increased circulating levels of pro-inflammatory (TNFα) and Th1-associated cytokines (IL-12p70) as well as several chemokines (CXCL11 and CX3CL1). However, no statistically significant differences were found in the numbers of cells, the concentrations of protein and urea as well as cytokine levels in the BALFs of HIV-positive patients when compared to controls. Correlation analysis indicated a potential modulatory effect of the BMI in HIV-seropositive individuals.

CONCLUSIONS

While our results are consistent with the existence of a systemic pro-inflammatory state in HIV-infected patients, they did not detect significant differences in cytokine levels and other inflammatory markers in the lungs of HIV-positive individuals when compared to HIV-negative controls.

Plasma cysteine/cystine and glutathione/glutathione disulfide redox potentials in HIV and COPD patients

Chronic obstructive pulmonary disease (COPD) is prevalent in patients infected with HIV. The purpose of this study was to test the hypothesis that systemic oxidation correlates with loss of lung function in subjects with COPD, and that HIV infection can contribute to creating such an environment. Subjects were recruited at the University of Louisville in the following groups: HIV-infected (n = 36), COPD (n = 32), HIV and COPD (n = 28), and uninfected controls with normal lung function (n = 34). HIV infection was assessed by viral load and CD4 cell counts. Pulmonary function was determined by spirometry, and plasma was collected for measurement of cysteine (Cys), cystine (CySS), glutathione (GSH) and GSH disulfide (GSSG) by HPLC followed by estimation of redox potentials (E_h) using the Nernst equation. Results showed that patients with COPD had more oxidized plasma E_h Cys/CySS than patients with normal lung function, but plasma E_h GSH/GSSG was unaltered. In addition, there was a correlation between the extent of plasma E_h Cys/CySS oxidation and loss of lung function, and this correlation remained even after correcting for age, sex, race and body mass index. HIV infection per se was not associated with increased oxidation of plasma E_h Cys/CySS, but plasma E_h Cys/CySS was more oxidized in patients with lower CD4-positve T cell counts. In patients with both HIV infection and COPD, there was a significant correlation between CD4 cell counts and lung function. Thus, systemic oxidation correlated with decreased lung function in subjects with COPD and decreased CD4 counts in subjects infected with HIV. Thus, factors contributing to plasma E_h Cys/CySS may represent novel mechanisms underlying the increased prevalence of COPD in people living with HIV.

Effectiveness of 13-Valent Pneumococcal Conjugate Vaccine Against Hospitalization for Community-Acquired Pneumonia in Older US Adults: A Test-Negative Design

Background

Following universal recommendation for use of 13-valent pneumococcal conjugate vaccine (PCV13) in US adults aged ≥65 years in September 2014, we conducted the first real-world evaluation of PCV13 vaccine effectiveness (VE) against hospitalized vaccine-type community-acquired pneumonia (CAP) in this population.

Methods

Using a test-negative design, we identified cases and controls from a population-based surveillance study of adults in Louisville, Kentucky, who were hospitalized with CAP. We analyzed a subset of CAP patients enrolled 1 April 2015 through 30 April 2016 who were aged ≥65 years and consented to have their pneumococcal vaccination history confirmed by health insurance records. Cases were defined as hospitalized CAP patients with PCV13 serotypes identified via culture or serotype-specific urinary antigen detection assay. Remaining CAP patients served as test-negative controls.

Results

Of 2034 CAP hospitalizations, we identified PCV13 serotypes in 68 (3.3%) participants (ie, cases), of whom 6 of 68 (8.8%) had a positive blood culture. Cases were less likely to be immunocompromised (29.4% vs 46.4%, P = .02) and overweight or obese (41.2% vs 58.6%, P = .01) compared to controls, but were otherwise similar. Cases were less likely to have received PCV13 than controls (3/68 [4.4%] vs 285/1966 [14.5%]; unadjusted VE, 72.8% [95% confidence interval, 12.8%−91.5%]). No confounding was observed during adjustment for patient characteristics, including immunocompromised status, body mass index, and history of influenza and pneumococcal polysaccharide vaccination (adjusted VE range, 71.1%−73.3%).

Conclusions

Our study is the first to demonstrate real-world effectiveness of PCV13 against vaccine-type CAP in adults aged ≥65 years following introduction into a national immunization program.

A Randomized Study Evaluating the Effectiveness of Oseltamivir Initiated at the Time of Hospital Admission in Adults Hospitalized With Influenza-Associated Lower Respiratory Tract Infections

Background

Influenza-associated hospitalizations result in high morbidity and mortality. We sought to determine if early empiric anti-influenza therapy improves outcomes of hospitalized patients with influenza-associated lower respiratory tract infections (I-LRTIs).

Methods

This was a randomized, unblinded, trial of adult patients hospitalized with I-LRTIs in Kentucky during 2009-2012. Patients were randomized to group A (standard of care) or group B (standard of care plus oseltamivir as early as possible but within 24 hours of enrollment). The primary outcome was development of clinical failure (composite variable including failure to reach clinical improvement within 7 days, transfer to intensive care 24 hours after admission, or rehospitalization or death within 30 days). Intent-to-treat (ITT) (all LRTI) and per-protocol (PP) (I-LRTI) analyses were done.

Results

A total of 1107 patients were enrolled and included in the ITT analysis, 556 in group A and 551 in group B. The median time from symptom onset to hospital admission was 5 days (interquartile range, 5) for both groups; oseltamivir was initiated median day 6 in group B. There was no difference in the development of clinical failure (group A, 25%, and group B, 24%; P = .561). In the PP analysis, 11 of 45 (24%) patients in group A and 4 of 29 (14%) patients in group B had clinical failure (P = .414).

Conclusions

Initiation of oseltamivir more than 5 days after illness onset did not reduce clinical failures among hospitalized patients with I- LRTIs. However, we did not enroll our projected sample size of I-LRTI.

Clinical Trials Registration

NCT01248715.

2722. Effects of Sex, Age, and Race on Immunogenicity of MenB-FHbp, a Bivalent Meningococcal B Vaccine: A Pooled Evaluation of Clinical Trial Data

Background

MenB-FHbp (bivalent rLP2086), a meningococcal serogroup B vaccine, is approved in several countries for adolescents and young adults. MenB-FHbp elicited robust immune responses and had an acceptable safety profile during an extensive clinical development program. Because immune responses to vaccines can vary by subject demographics, this subgroup analysis pooled data across 7 randomized MenB-FHbp clinical studies to evaluate potential differences in immunogenicity by sex, age, or race/ethnicity in a larger dataset relative to individual studies.

Methods

Data from subjects who received 120 µg MenB-FHbp at 0, 2, and 6 months and had valid immunogenicity results for 4 vaccine-heterologous test strains were included. Immune responses were evaluated by serum bactericidal assays using human complement (hSBA). Immunogenicity endpoints (assessed 1 month after dose 3) were percentages of subjects achieving ≥ 4-fold rise in hSBA titer against each strain, percentages achieving hSBA titers ≥ the lower limit of quantification (LLOQ) against each strain and against all 4 strains combined (composite response), geometric mean hSBA titers against each strain, and percentages achieving hSBA titers ≥ 1:4 (correlate of protection) against each strain.

Results

This analysis included 8026 subjects aged 10‒25 years (51.7% males, 80.7% adolescents aged 10‒18 years, 87.0% white, 9.3% black, 0.8% Asian, 3.0% other race). One month after dose 3, percentages of subjects achieving a ≥ 4-fold rise from baseline titer against each strain and achieving a composite response were similar across age and race (table). A marginally greater percentage of males vs. females achieved ≥ 4-fold rise in titer against each strain, but these differences were not considered clinically meaningful because of the high percentages of responders in both groups.

Conclusion

MenB-FHbp immunogenicity was similar across sex, age, and race in this pooled analysis, with high percentages of responders in all evaluated subgroups. The marginally lower response rates among females compared with males were not considered clinically meaningful. These findings support currently recommended MenB-FHbp vaccination practices without modification by sex, age, or race.

Funding: Pfizer

Disclosures

All authors: No reported disclosures.

1478. Efficacy and Safety of a Booster Dose of the MenACWY-TT Vaccine Administered 10 Years After Primary Vaccination with MenACWY-TT or MenACWY-PS

Background

The quadrivalent meningococcal ACWY polysaccharide tetanus toxoid conjugate vaccine (MenACWY-TT; Nimenrix) is licensed in various countries to prevent disease caused by meningococcal serogroups A, C, W, and Y. In a previous study (NCT00464815), subjects aged 11‒17 years received a primary dose of MenACWY-TT or a quadrivalent polysaccharide vaccine (MenACWY-PS). Here, we report the long-term antibody persistence of the primary dose and the immunogenicity and safety of a booster dose given 10 years after primary vaccination of subjects.

Methods

Participants were enrolled from the Philippines and received a booster dose of MenACWY-TT at 10 years postvaccination. Antibody persistence 10 years postprimary vaccination and immunogenicity 1 month after the booster dose were evaluated by serum bactericidal activity assays using rabbit complement (rSBA) to assess the percentages of subjects with titers ≥1:8 and ≥1:128 and geometric mean titers (GMTs) for each serogroup. Safety was assessed for the booster dose.

Results

Of 229 subjects enrolled in this extension study, 169 and 58 subjects in the MenACWY-TT and MenACWY-PS groups, respectively, completed the booster phase. The percentages of primary MenACWY-TT recipients with prebooster rSBA titers ≥ 1:8 and ≥ 1:128 at year 10 ranged from 71.6%‒90.7% and 64.8%‒85.2% for all serogroups, respectively, compared with 43.1%‒82.4% and 25.5%‒76.5% of primary MenACWY-PS recipients; rSBA GMTs for all serogroups were higher in the MenACWY-TT group than in the MenACWY-PS group at year 10. For the MenACWY-TT and MenACWY-PS groups, respectively, the MenACWY-TT booster dose elicited rSBA titers ≥1:8 in 100% and ≥98.0% of subjects (figure); 100% and ≥96.1% of all subjects had titers ≥1:128. For all serogroups, rSBA GMTs at 1 month after the booster dose were higher than before the booster dose. No new safety signals were observed during the booster phase.

Conclusion

Functional antibody responses elicited by MenACWY-TT persisted 10 years after primary vaccination; the booster dose was well tolerated and elicited robust immune responses.

ClinicalTrials.gov: NCT03189745, EudraCT # 2013-001512-29. Funded by Pfizer.

Disclosures

All authors: No reported disclosures.

Incidence and Mortality of Adults Hospitalized With Community-Acquired Pneumonia According to Clinical Course

BACKGROUND

After hospitalization for community-acquired pneumonia (CAP), patients' clinical course may progress to clinical improvement, clinical failure, or nonresolving pneumonia. The epidemiology and outcomes of patients with CAP according to clinical course has not been well studied. The objective of this study was to characterize the incidence and outcomes for each clinical course of hospitalized patients with CAP.

METHODS

This was a secondary data analysis of the University of Louisville Pneumonia Study. Clinical course was classified as improvement, failure, and nonresolving. Objective criteria were used to define improvement and failure during the first week of hospitalization. If neither group of criteria were met, the course was classified as nonresolving. Incidence for each clinical course was calculated. Mortality was evaluated at different time points through the first year. P < .05 was considered statistically significant.

RESULTS

A total of 7,449 patients were hospitalized with CAP during the study period. Improvement was documented in 5,732 patients (77%), failure was documented in 1,458 patients (20%), and nonresolving CAP was documented in 259 patients (3%). Mortality at 30 days was 6% for those who improved, 34% for those who failed, and 34% for those with nonresolving pneumonia. Mortality at 1 year was 23%, 52%, and 51%, respectively.

CONCLUSIONS

This study shows that > 75% of hospitalized patients with CAP will reach clinical improvement. One of two patients with clinical failure or nonresolving CAP may die 1 year after hospitalization. Understanding the pathogenesis of long-term mortality is critical to developing interventions.

Future Research Directions in Pneumonia. NHLBI Working Group Report

Pneumonia is a complex pulmonary disease in need of new clinical approaches. Although triggered by a pathogen, pneumonia often results from dysregulations of host defense that likely precede infection. The coordinated activities of immune resistance and tissue resilience then dictate whether and how pneumonia progresses or resolves. Inadequate or inappropriate host responses lead to more severe outcomes such as acute respiratory distress syndrome and to organ dysfunction beyond the lungs and over extended time frames after pathogen clearance, some of which increase the risk for subsequent pneumonia. Improved understanding of such host responses will guide the development of novel approaches for preventing and curing pneumonia and for mitigating the subsequent pulmonary and extrapulmonary complications of pneumonia. The NHLBI assembled a working group of extramural investigators to prioritize avenues of host-directed pneumonia research that should yield novel approaches for interrupting the cycle of unhealthy decline caused by pneumonia. This report summarizes the working group's specific recommendations in the areas of pneumonia susceptibility, host response, and consequences. Overarching goals include the development of more host-focused clinical approaches for preventing and treating pneumonia, the generation of predictive tools (for pneumonia occurrence, severity, and outcome), and the elucidation of mechanisms mediating immune resistance and tissue resilience in the lung. Specific areas of research are highlighted as especially promising for making advances against pneumonia.

Pneumococcal epidemiology among us adults hospitalized for community-acquired pneumonia

BACKGROUND

Few studies have measured the burden of adult pneumococcal disease after the introduction of 13-valent pneumococcal conjugate vaccine (PCV13) into the US infant vaccination schedule. Further, most data regarding pneumococcal serotypes are derived from invasive pneumococcal disease (IPD), which represents only a fraction of all adult pneumococcal disease burden. Understanding which pneumococcal serotypes cause pneumonia in adults is critical for informing current immunization policy. The objective of this study was to measure the proportion of radiographically-confirmed (CXR+) community-acquired pneumonia (CAP) caused by PCV13 serotypes in hospitalized US adults.

METHODS

This observational, prospective surveillance study recruited hospitalized adults aged ≥18 years from 21 acute care hospitals across 10 geographically-dispersed cities in the United States between October 2013 and September 2016. Clinical and demographic data were collected during hospitalization. Vital status was ascertained 30 days after enrollment. Pneumococcal serotypes were detected via culture from the respiratory tract and normally-sterile sites (including blood and pleural fluid). Additionally, a novel, Luminex-based serotype-specific urinary antigen detection (UAD) assay was used to detect serotypes included in PCV13.

RESULTS

Of 15,572 enrolled participants, 12,055 eligible patients with CXR+CAP were included in the final analysis population. Mean age was 64.1 years and 52.7% were aged ≥65 years. Common comorbidities included chronic obstructive pulmonary disease (43.0%) and diabetes mellitus (28.6%). PCV13 serotypes were detected in 552/12,055 (4.6%) of all patients and 265/6347 (4.2%) of those aged ≥65 years. Among patients aged 18-64 years PCV13 serotypes were detected in 3.8-5.3% of patients depending on their risk status.

CONCLUSIONS

After implementation of a pneumococcal conjugate vaccination program in US children, and despite the herd protection observed in US adults, a persistent burden of PCV13-type CAP remains in this population.

Examining age as a moderating effect on the relationship between alcohol use and viral suppression among women living with HIV

This study sought to examine if age moderated the effect of alcohol on viral suppression among women living with HIV. A secondary data analysis, using data from the 550 Clinic Women's HIV Cohort Study was completed. Individuals were included if they were HIV positive, sought care in an urban clinic in Kentucky between 2009 and 2012, and had ≥1 year of follow-up. The primary independent variable was current alcohol use; the moderating variable was age (<50 years versus ≥50 years); and the outcome was suppression. Logistic regression models examined the interaction between age and alcohol. Among 360 women (average age 45.8 ± 10.1 years, 38 percent were ≥50 years), approximately 32.0 percent had consumed alcohol, and 40 percent achieved suppression. Women aged ≥50 years were more likely to achieve suppression than younger women. Age interacted significantly with alcohol (p = .038). Stratified by age, alcohol was associated with poor viral suppression among older women; for older women, alcohol users had lower odds of suppression compared to nonusers (odds ratio = 0.37; 95 percent confidence interval = 0.14-0.99). Alcohol may impede the opportunity for older women to achieve suppression. Further study is needed to examine alcohol use among older women, specifically addressing quantity and frequency and their impact on suppression.

The burden of community-acquired bacterial pneumonia in the era of antibiotic resistance

INTRODUCTION

Community-acquired pneumonia (CAP) is a significant global health problem and leading cause of death and hospitalization in both the US and abroad. Increasing macrolide resistance among Streptococcus pneumoniae and other pathogens results in a greater disease burden, along with changing demographics and a higher preponderance of comorbid conditions. Areas covered: This review summarizes current data on the clinical and economic burden of CAP, with particular focus on community-acquired bacterial pneumonia (CABP). Incidence, morbidity and mortality, and healthcare costs for the US and other regions of the world are among the topics covered. Major factors that are believed to be contributing to the increased impact of CABP, including antimicrobial resistance, the aging population, and the incidence of comorbidities are discussed, as well as unmet needs in current CABP management. Expert commentary: The clinical and economic burden of CABP is staggering, far-reaching, and expected to increase in the future as new antibiotic resistance mechanisms emerge and the world's population ages. Important measures must be initiated to stabilize and potentially decrease this burden. Urgent needs in CABP management include the development of new antimicrobials, adjuvant therapies, and rapid diagnostics.

2285. Burden of Invasive and Non-Invasive Group B Streptococcal Infections in Hospitalized Adults, Louisville, Kentucky: A Large Population-Based Study

Background

Methods

Results

Conclusion

Disclosures

Macrolide therapy is associated with lower mortality in community-acquired bacteraemic pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) has a potential complication of bacteremia. The objective of this study was to define the clinical outcomes of patients with CAP and bacteremia treated with and without a macrolide.

MATERIALS AND METHODS

Secondary analysis of the Community-Acquired Pneumonia Organization database of hospitalized patients with CAP. Patients with a positive blood culture were categorized based on the presence or absence of a macrolide in their initial antimicrobial regimen, and severity of their CAP. Outcomes included in-hospital all-cause mortality, 30-day mortality, length of stay, and time to clinical stability.

RESULTS

Among 549 patients with CAP and bacteremia, 247 (45%) were treated with a macrolide and 302 (55%) were not. The primary pathogen was Streptococcus pneumoniae (74%). Poisson regression with robust error variance models were used to compare the adjusted effects of each study group on the outcomes. The unadjusted 30-day mortality was 18.4% in the macrolide group, and 29.6% in the non-macrolide group (adjusted relative risk (aRR)0.81; 95% confidence interval (CI)0.50-1.33; P = 0.41). Unadjusted in-hospital all-cause mortality was 7.3% in the macrolide group, and 18.9% in the non-macrolide group (aRR 0.54, 95% CI 0.30-0.98; P = 0.043). Length of stay and time to clinical stability were not significantly different.

CONCLUSIONS

In-hospital mortality, but not 30-day mortality, was significantly better in the macrolide group. Our data support the use of a macrolide in hospitalized patients with CAP and bacteraemia.

Tenofovir alafenamide plus emtricitabine versus abacavir plus lamivudine for treatment of virologically suppressed HIV-1-infected adults: a randomised, double-blind, active-controlled, non-inferiority phase 3 trial

BACKGROUND

Abacavir and tenofovir alafenamide offer reduced bone toxicity compared with tenofovir disoproxil fumarate. We aimed to compare safety and efficacy of tenofovir alafenamide plus emtricitabine with that of abacavir plus lamivudine.

METHODS

In this randomised, double-blind, active-controlled, non-inferiority phase 3 trial, HIV-1-positive adults (≥18 years) were screened at 79 sites in 11 countries in North America and Europe. Eligible participants were virologically suppressed (HIV-1 RNA <50 copies per mL) and on a stable three-drug regimen containing abacavir plus lamivudine. Participants were randomly assigned (1:1) by a computer-generated allocation sequence (block size 4) to switch to fixed-dose tablets of tenofovir alafenamide (10 mg or 25 mg) plus emtricitabine (200 mg) or remain on abacavir (600 mg) plus lamivudine (300 mg), with matching placebo, while continuing to take the third drug. Randomisation was stratified by the third drug (boosted protease inhibitor vs other drug) at screening. Investigators, participants, and study staff giving treatment, assessing outcomes, and collecting data were masked to treatment group. The primary endpoint was the proportion of participants with virological suppression (HIV-1 RNA <50 copies per mL) at week 48 (assessed by snapshot algorithm), with a 10% non-inferiority margin. We analysed the primary endpoint in participants enrolled before May 23, 2016 (when target sample size was reached), and we analysed safety in all enrolled participants who received at least one dose of study drug (including patients enrolled after these dates). This study was registered with ClinicalTrials.gov, number NCT02469246.

FINDINGS

Study enrolment began on June 29, 2015, and the cutoff enrolment date for the week 48 primary endpoint analysis was May 23, 2016. 501 participants were randomly assigned and treated. At week 48, virological suppression was maintained in 227 (90%) of 253 participants receiving tenofovir alafenamide plus emtricitabine compared with 230 (93%) of 248 receiving abacavir plus lamivudine (difference -3·0%, 95% CI -8·2 to 2·0), showing non-inferiority. Few participants discontinued treatment because of adverse events: 12 (4%) of 280 participants in the tenofovir alafenimide plus emtricitabine group and nine (3%) of 276 in the abacavir plus lamivudine group. Three participants had serious, treatment-related adverse events: one each with renal colic and neutropenia in the tenofovir alafenamide plus emtricitabine group, and one myocardial infarction in the abacavir plus lamivudine group. There were no treatment-related deaths.

INTERPRETATION

Tenofovir alafenamide, in combination with emtricitabine and various third drugs, maintained high efficacy with a renal and bone safety profile similar to that of abacavir. In virologically suppressed patients, a regimen containing tenofovir alafenamide could be an alternative to those containing abacavir, without concern for new onset of renal or bone toxicities or hyperlipidaemia.

FUNDING

Gilead Sciences Inc.

Detailed Transmission Network Analysis of a Large Opiate-Driven Outbreak of HIV Infection in the United States

In January 2015, an outbreak of undiagnosed human immunodeficiency virus (HIV) infections among persons who inject drugs (PWID) was recognized in rural Indiana. By September 2016, 205 persons in this community of approximately 4400 had received a diagnosis of HIV infection. We report results of new approaches to analyzing epidemiologic and laboratory data to understand transmission during this outbreak. HIV genetic distances were calculated using the polymerase region. Networks were generated using data about reported high-risk contacts, viral genetic similarity, and their most parsimonious combinations. Sample collection dates and recency assay results were used to infer dates of infection. Epidemiologic and laboratory data each generated large and dense networks. Integration of these data revealed subgroups with epidemiologic and genetic commonalities, one of which appeared to contain the earliest infections. Predicted infection dates suggest that transmission began in 2011, underwent explosive growth in mid-2014, and slowed after the declaration of a public health emergency. Results from this phylodynamic analysis suggest that the majority of infections had likely already occurred when the investigation began and that early transmission may have been associated with sexual activity and injection drug use. Early and sustained efforts are needed to detect infections and prevent or interrupt rapid transmission within networks of uninfected PWID.

Antiretroviral Therapy Prescribing Practices and Virologic Response in HIV-Infected Individuals with the M184V Mutation: Results from the 550 Clinic Cohort Study

Background

Human immunodeficiency virus (HIV) treatment guidelines recommend using a regimen that contains three fully active antiretroviral agents in patients with drug resistance mutations. However, some evidence suggests that protease inhibitor (PI) based regimens containing less than three fully active drugs may be as efficacious in achieving viral suppression (VS) as a three-drug regimen in the presence of a M184V mutation. The purpose of this study was to identify current prescribing practices and determine if VS can be achieved with regimens containing less than three fully active agents in patients with a M184V mutation.

Methods

A single-center retrospective chart review was conducted on patients receiving treatment at the 550 Clinic from January 2003 to July 2016. Patients were screened for a M184V mutation. Patients were excluded for lack of a genotype and inadequate documentation of viral load (VL) prior to initiating or changing therapy. Regimens were characterized as containing three fully active agents or less and evaluated for VS success (VL less than 200 copies/mL). Data was analyzed using descriptive statistics, Chi-square tests, and Fischer’s exact tests.

Results

A M184V mutation was identified in 100 of the 754 patients screened for inclusion. 90% of the 167 regimens evaluated contained less than three fully active drugs. PI-based regimens (n = 86) and integrase strand transfer inhibitor (INSTI)-based regimens (n = 25) were the most commonly prescribed regimens containing less than three fully active drugs. VS was achieved with 72% of regimens containing less than three fully active agents compared with 69% of those containing three fully active agents (P = 0.108). In patients with a baseline VL greater than 100,000 copies/mL, VS was achieved with 80% of INSTI-based regimens compared with 21% of PI-based regimens (P = 0.040). VS was achieved with 85% of INSTI-based regimens and 78% of PI-based regimens in those with a baseline VL less than 100,000 copies/mL (P = 0.513).

Conclusion

Regimens containing less than three fully active drugs may be as efficacious as regimens containing three fully active drugs in those with a M184V mutation. In those with a high baseline VL, INSTI-based regimens may have better efficacy compared with PI-based regimens.

Disclosures

All authors: No reported disclosures.

Gender Differences in Virologic Response after Antiretroviral Therapy in Treatment-naïve HIV-infected Individuals: Results from the 550 Clinic HIV Cohort Study

Background

Controversy still exists regarding gender differences in virologic response between treatment-na•ve HIV-infected individuals. The objective of this study was to evaluate gender difference in virologic and immunologic response to antiretroviral therapy in treatment-na•ve HIV-infected individuals.

Methods

This was a retrospective, observational study of treatment-na•ve HIV-infected individuals managed at the 550 clinic who started antiretroviral therapy (ART) between January 1^st, 2010 and December 31, 2015. Patients with available viral load and CD4 counts before and one year after initiating ART were included in this study. Virologic suppression was defined as < 48 HIV-1 RNA copies/mL, and mmunologic recovery was defined as a CD4 count increase of at least 150 cells/mm³. Dichotomous variables were reported in number and percentages and analyzed using Chi-squared tests and Fisher’s exact (whichever was appropriate). Continuous variables were reported as median and interquartile range (IQR) and analyzed using Wilcox rank-sum tests. Multivariate analyses performed were logistic regressions with adjustment for other covariates. P value <0.05 was considered statistically significant. R version 3.3.2 was used for the statistical analysis.

Results

A total of 70 women and 90 men were included in the study. Median age was 41 years (19) for women and 34 years (19) for men (P < 0.001). Virologic suppression was documented in 76% of women and 64% of men (p 0.166). Immune recovery was documented in 60% of women and 68% of men (p 0.323). Multivariate analysis of virologic success is shown in Figure 1 and immunologic recovery is shown in Figure 2.

Conclusion

In our study, gender was not found to be associated with differences in response to ART. As expected, drug abuse continues to be an independent variable associated with lack of virologic suppression. If one of the goals of treatment is to achieve a rapid immunologic response, our study may indicate that regimens containing protease inhibitors should be the ones selected.

Disclosures

All authors: No reported disclosures.

Telavancin for the treatment of methicillin-resistant Staphylococcus aureus bone and joint infections

This retrospective, case series describes our experience with the use of telavancin in patients with methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis and prosthetic joint infection. The primary objectives were clinical outcomes and adverse events (AEs), and a secondary outcome described microbiological susceptibility. Fourteen patients were enrolled. Median duration of therapy was 58 days, and four patients had concurrent bacteremia. End-of-treatment outcomes were available in 78% of patients, with a clinical success rate of 91%. Thirty-day and 12-month outcomes were also obtained. Seven patients experienced AEs. Infusion-related reactions were most common, and three AEs required discontinuation of therapy. All MRSA isolates had a telavancin MIC ≤0.06μg/ml, which is susceptible. This study indicates that telavancin may have a role in treatment of MRSA osteomyelitis and prosthetic joint infection. Our study describes clinical success and adverse events for long duration of therapy, up to 8 weeks.

The order of administration of macrolides and beta-lactams may impact the outcomes of hospitalized patients with community-acquired pneumonia: results from the community-acquired pneumonia organization

BACKGROUND

The beneficial effect of macrolides for the treatment of community-acquired pneumonia (CAP) in combination with beta-lactams may be due to their anti-inflammatory activity. In patients with pneumococcal meningitis, the use of steroids improves outcomes only if they are administered before beta-lactams. The objective of this study was to compare outcomes in hospitalized patients with CAP when macrolides were administered before, simultaneously with, or after beta-lactams.

METHODS

Secondary data analysis of the Community-Acquired Pneumonia Organization (CAPO) International Cohort Study database. Study groups were defined based on the sequence of administration of macrolides and beta-lactams. The study outcomes were time to clinical stability (TCS), length of stay (LOS) and in-hospital mortality. Accelerated failure time models were used to evaluate the adjusted impact of sequential antibiotic administration and time-to-event outcomes, while a logistic regression model was used to evaluate their adjusted impact on mortality.

RESULTS

A total of 99 patients were included in the macrolide before group and 305 in the macrolide after group. Administration of a macrolide before a beta-lactam compared to after a beta-lactam reduced TCS (3 vs. 4 days, p = .011), LOS (6 vs. 7 days, p = .002) and mortality (3 vs. 7.2%, p = .228).

CONCLUSIONS

The administration of macrolides before beta-lactams was associated with a statistically significant decrease in TCS and LOS and a non-statistically significant decrease in mortality. The beneficial effect of macrolides in hospitalized patient with CAP may occur only if administered before beta-lactams.

Using cluster analysis of cytokines to identify patterns of inflammation in hospitalized patients with community-acquired pneumonia: a pilot study

INTRODUCTION

Patients with severe community-acquired pneumonia (CAP) are believed to have an exaggerated inflammatory response to bacterial infection. Therapies aiming to modulate the inflammatory response have been largely unsuccessful, perhaps reflecting that CAP is a heterogeneous disorder that cannot be modulated by a single anti-inflammatory approach. We hypothesize that the host inflammatory response to pneumonia may be characterized by distinct cytokine patterns, which can be harnessed for personalized therapies.

METHODS

Here, we use hierarchical cluster analysis of cytokines to examine if patterns of inflammatory response in 13 hospitalized patients with CAP can be defined. This was a secondary data analysis of the Community-Acquired Pneumonia Inflammatory Study Group (CAPISG) database. The following cytokines were measured in plasma and sputum on the day of admission: interleukin (IL)-1β, IL-1 receptor antagonist (IL-1ra), IL-6, CXCL8 (IL-8), IL-10, IL-12p40, IL-17, interferon (IFN)γ, tumor necrosis factor (TNF)α, and CXCL10 (IP-10). Hierarchical agglomerative clustering algorithms were used to evaluate clusters of patients within plasma and sputum cytokine determinations.

RESULTS

A total of thirteen patients were included in this pilot study. Cluster analysis identified distinct inflammatory response patterns of cytokines in the plasma, sputum, and the ratio of plasma to sputum.

CONCLUSIONS

Inflammatory response patterns in plasma and sputum can be identified in hospitalized patients with CAP. Characterization of the local and systemic inflammatory response may help to better discriminate patients for enrollment into clinical trials of immunomodulatory therapies.

Using cluster analysis of cytokines to identify patterns of inflammation in hospitalized patients with community-acquired pneumonia: a pilot study

INTRODUCTION

Patients with severe community-acquired pneumonia (CAP) are believed to have an exaggerated inflammatory response to bacterial infection. Therapies aiming to modulate the inflammatory response have been largely unsuccessful, perhaps reflecting that CAP is a heterogeneous disorder that cannot be modulated by a single anti-inflammatory approach. We hypothesize that the host inflammatory response to pneumonia may be characterized by distinct cytokine patterns, which can be harnessed for personalized therapies.

METHODS

Here, we use hierarchical cluster analysis of cytokines to examine if patterns of inflammatory response in 13 hospitalized patients with CAP can be defined. This was a secondary data analysis of the Community-Acquired Pneumonia Inflammatory Study Group (CAPISG) database. The following cytokines were measured in plasma and sputum on the day of admission: interleukin (IL)-1β, IL-1 receptor antagonist (IL-1ra), IL-6, CXCL8 (IL-8), IL-10, IL-12p40, IL-17, interferon (IFN)γ, tumor necrosis factor (TNF)α, and CXCL10 (IP-10). Hierarchical agglomerative clustering algorithms were used to evaluate clusters of patients within plasma and sputum cytokine determinations.

RESULTS

A total of thirteen patients were included in this pilot study. Cluster analysis identified distinct inflammatory response patterns of cytokines in the plasma, sputum, and the ratio of plasma to sputum.

CONCLUSIONS

Inflammatory response patterns in plasma and sputum can be identified in hospitalized patients with CAP. Characterization of the local and systemic inflammatory response may help to better discriminate patients for enrollment into clinical trials of immunomodulatory therapies.