Vaccination of COPD patients with a pneumococcus type 6B tetanus toxoid conjugate vaccine

A Comparison between Two Pathophysiologically Different yet Microbiologically Similar Lung Diseases: Cystic Fibrosis and Chronic Obstructive Pulmonary Disease

Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are chronic pulmonary diseases that affect ~70,000 and 251 million individuals worldwide, respectively. Although these two diseases have distinctly different pathophysiologies, both cause chronic respiratory insufficiency that erodes quality of life and causes significant morbidity and eventually death. In both CF and COPD, the respiratory microbiome plays a major contributing role in disease progression and morbidity. Pulmonary pathogens can differ dramatically during various stages of each disease and frequently cause acute worsening of lung function due to disease exacerbation. Despite some similarities, outcome and timing/type of exacerbation can also be quite different between CF and COPD. Given these clinical distinctions, both patients and physicians should be aware of emerging therapeutic options currently being offered or in development for the treatment of lung infections in individuals with CF and COPD. Although interventions are available that prolong life and mitigate morbidity, neither disorder is curable. Both acute and chronic pulmonary infections contribute to an inexorable downward course and may trigger exacerbations, culminating in loss of lung function or respiratory failure. Knowledge of the pulmonary pathogens causing these infections, their clinical presentation, consequences, and management are, therefore, critical. In this review, we compare and contrast CF and COPD, including underlying causes, general outcomes, features of the lung microbiome, and potential treatment strategies.

Pneumococcal vaccines for preventing pneumonia in chronic obstructive pulmonary disease

BACKGROUND

People with chronic obstructive pulmonary disease (COPD) are at increased risk of pneumococcal disease, especially pneumonia, as well as acute exacerbations with associated morbidity and healthcare costs.

OBJECTIVES

To determine the efficacy of injectable pneumococcal vaccination for preventing pneumonia in persons with COPD.

SEARCH METHODS

We searched the Cochrane Airways COPD Trials Register and the databases CENTRAL, MEDLINE and Embase, using prespecified terms. Searches are current to November 2016.

SELECTION CRITERIA

We included randomised controlled trials (RCT) comparing injectable pneumococcal polysaccharide vaccine (PPV) or pneumococcal conjugated vaccine (PCV) versus a control or alternative vaccine type in people with COPD.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. For meta-analyses, we subgrouped studies by vaccine type.

MAIN RESULTS

For this update, we added five studies (606 participants), meaning that the review now includes a total of 12 RCTs involving 2171 participants with COPD. Average age of participants was 66 years, male participants accounted for 67% and mean forced expiratory volume in one second (FEV₁) was 1.2 L (five studies), 54% predicted (four studies). We assessed risks of selection, attrition and reporting bias as low, and risks of performance and detection bias as moderate.Compared with control, the vaccine group had a lower likelihood of developing community-acquired pneumonia (CAP) (odds ratio (OR) 0.62, 95% confidence interval (CI) 0.43 to 0.89; six studies, n = 1372; GRADE: moderate), but findings did not differ specifically for pneumococcal pneumonia (Peto OR 0.26, 95% CI 0.05 to 1.31; three studies, n = 1158; GRADE: low). The number needed to treat for an additional beneficial outcome (NNTB) (preventing one episode of CAP) was 21 (95% CI 15 to 74). Mortality from cardiorespiratory causes did not differ between vaccine and control groups (OR 1.07, 95% CI 0.69 to 1.66; three studies, n = 888; GRADE: moderate), nor did all-cause mortality differ (OR 1.00, 95% CI 0.72 to 1.40; five studies, n = 1053; GRADE: moderate). The likelihood of hospital admission for any cause, or for cardiorespiratory causes, did not differ between vaccine and control groups. Vaccination significantly reduced the likelihood of a COPD exacerbation (OR 0.60, 95% CI 0.39 to 0.93; four studies, n = 446; GRADE: moderate). The NNTB to prevent a patient from experiencing an acute exacerbation was 8 (95% CI 5 to 58). Only one study (n = 181) compared the efficacy of different vaccine types - 23-valent PPV versus 7-valent PCV - and reported no differences for CAP, all-cause mortality, hospital admission or likelihood of a COPD exacerbation, but investigators described a greater likelihood of some mild adverse effects of vaccination with PPV-23.

AUTHORS' CONCLUSIONS

Injectable polyvalent pneumococcal vaccination provides significant protection against community-acquired pneumonia, although no evidence indicates that vaccination reduced the risk of confirmed pneumococcal pneumonia, which was a relatively rare event. Vaccination reduced the likelihood of a COPD exacerbation, and moderate-quality evidence suggests the benefits of pneumococcal vaccination in people with COPD. Evidence was insufficient for comparison of different pneumococcal vaccine types.

Injectable vaccines for preventing pneumococcal infection in patients with chronic obstructive pulmonary disease

BACKGROUND

As chronic obstructive pulmonary disease (COPD) progresses, exacerbations can occur with increasing frequency. One goal of therapy is to prevent these exacerbations, thereby reducing morbidity and associated healthcare costs. Pneumococcal vaccinations are one strategy for reducing the risk of infective exacerbations.

OBJECTIVES

To determine the safety and efficacy of pneumococcal vaccination in COPD. The primary outcomes assessed were episodes of pneumonia and acute exacerbations. Secondary outcomes of interest included hospital admissions, adverse events related to treatment, disability, change in lung function, mortality, and cost effectiveness.

SEARCH STRATEGY

We searched the Cochrane Airways Group COPD trials register and the databases CENTRAL, MEDLINE and EMBASE using pre-specified terms. The latest searches were performed in March 2010.

SELECTION CRITERIA

Randomised controlled trials assessing the effects of injectable pneumococcal vaccine in people with COPD were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and three review authors independently assessed trial quality.

MAIN RESULTS

Seven studies were identified that met the inclusion criteria for this review and were included in the 2010 review update. Two older trials used a 14-valent vaccine and five more recent trials used a 23-valent injectable vaccine.In six studies involving 1372 people, the reduction in likelihood of developing pneumonia with pneumococcal vaccination compared to control did not achieve statistical significance, the odds ratio (OR) was 0.72 (95% confidence interval (CI) 0.51 to 1.01), with moderate heterogeneity present between studies. The reduction in likelihood of acute exacerbations of COPD from two studies involving 216 people was not statistically significant (Peto OR 0.58; 95% CI 0.30 to 1.13).Of the secondary outcomes for which data were available there was no statistically significant effect for reduction in hospital admissions (two studies) or emergency department visits (one study). There was no significant reduction in pooled results from three studies involving 888 people for odds of all-cause mortality for periods up to 48 months post-vaccination (OR 0.94; 95% CI 0.67 to 1.33), or for death from cardiorespiratory causes (OR 1.07; 95% CI 0.69 to 1.66).

AUTHORS' CONCLUSIONS

The limited evidence from randomised controlled trials (RCTs) included in this review suggests that, while it is possible that injectable polyvalent pneumococcal vaccines may provide some protection against morbidity in persons with COPD, no significant effect on any of the outcomes was shown. Further large RCTs in this population would be needed to confirm effectiveness of the vaccine suggested by results from longitudinal studies.

Superior immune response to protein-conjugate versus free pneumococcal polysaccharide vaccine in chronic obstructive pulmonary disease

RATIONALE

Debate exists about the immunogenicity and protective efficacy of antibodies produced by the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in chronic obstructive pulmonary disease (COPD). The 7-valent diphtheria-conjugated pneumococcal polysaccharide vaccine (PCV7) induces a more robust immune response than PPSV23 in healthy elderly adults.

OBJECTIVES

We hypothesized that serotype-specific IgG antibody concentration and functional antibody activity would be superior after PCV7 vaccination compared with PPSV23 in moderate to severe COPD. We also posited that older age and prior PPSV23 vaccination would be associated with reduced vaccine responsiveness.

METHODS

One hundred twenty patients with COPD were randomized to PPSV23 (63 subjects) or PCV7 (57 subjects). IgG concentrations were determined by ELISA; functional antibody activity was assayed with a standardized opsonophagocytosis assay and reported as an opsonization killing index (OPK). Increases in serotype-specific IgG and OPK at 1 month post vaccination were compared within and between vaccine groups.

MEASUREMENTS AND MAIN RESULTS

Both vaccines were well tolerated. Within each study group, postvaccination IgG and OPK were higher than baseline (P < 0.01) for all serotypes. Adjusted for baseline levels, postvaccination IgG was higher in the PCV7 group than the PPSV23 group for all seven serotypes, reaching statistical significance for five (P < 0.05). PCV7 resulted in a higher OPK for six of seven serotypes (statistically greater for four) compared with PPSV23. In multivariate analyses, younger age, vaccine naivety, and receipt of PCV7 were associated with increased OPK responses.

CONCLUSIONS

PCV7 induces a superior immune response at 1 month post vaccination compared with PPSV23 in COPD. Older age and prior PPSV23 reduce vaccine responsiveness. Clinical trial registered with www.clinicaltrials.gov (NCT00457977).

Pneumococcal Vaccination for Patients With COPD

Despite a level "A" recommendation by the Centers for Disease Control and Prevention, the use of pneumococcal polysaccharide vaccination in patients with COPD is supported by limited data. Clinical and laboratory studies have suggested that the currently approved vaccine is less effective in the population of COPD patients than in healthier patients, and to date no randomized-controlled trial of pneumococcal vaccination for COPD patients has demonstrated any beneficial effect. The implementation of a pneumococcal vaccine trial in the COPD population is problematic because of the large sample size required for studies examining clinical outcomes and the fact that no adequate in vitro assays have been available to serve as surrogate measures of vaccine protection. However, new laboratory methods have been developed and more accurate determination of the immunogenicity of pneumococcal vaccines is now possible. There is considerable interest in the development of an improved pneumococcal vaccine for patients with COPD, and advances in vaccine design hold considerable promise for improved prevention against pneumonia and acute exacerbations caused by Streptococcus pneumoniae. The following discussion will examine the available data supporting pneumococcal polysaccharide vaccine use, the currently available laboratory methods to measure immunogenicity, and advances in the development of an improved pneumococcal vaccine that could better protect patients with COPD against this pathogen.

Immunogenicity of varying dosages of 7-valent pneumococcal polysaccharide-protein conjugate vaccine in seniors previously vaccinated with 23-valent pneumococcal polysaccharide vaccine

In this dose-ranging study 220 seniors who had received the 23-valent pneumococcal polysaccharide (PnPS) vaccine at least 5 years prior to enrollment were assigned to receive one of four volumes (0.1, 0.5, 1 or 2 ml) of 7-valent pneumococcal conjugate (PnC) vaccine or a 0.5 ml dose of 23-valent PnPS vaccine. All participants received a reduced challenge dose of 0.1 ml of PnPS vaccine 1 year after enrollment. There was evidence of a dose response to PnC vaccine and antibody levels in the 1 ml PnC group tended to be significantly higher than in the PnPS group. A booster response to the challenge vaccination was not observed. Administration of a 1 ml dose of PnC vaccine is more immunogenic than 0.5 ml of PnPS vaccine in elderly adults previously vaccinated with PnPS vaccine.

Injectable vaccines for preventing pneumococcal infection in patients with chronic obstructive pulmonary disease

BACKGROUND

As chronic obstructive pulmonary disease (COPD) progresses, exacerbations can occur with increasing frequency. One goal of therapy in COPD is to try and prevent these exacerbations, thereby reducing disease morbidity and associated healthcare costs. Pneumococcal vaccinations are considered to be one strategy for reducing the risk of infective exacerbations.

OBJECTIVES

To determine the safety and efficacy of pneumococcal vaccination in COPD. The primary outcome assessed was acute exacerbations. Secondary outcomes of interest included episodes of pneumonia, hospital admissions, adverse events related to treatment, disability, change in lung function, mortality, and cost effectiveness.

SEARCH STRATEGY

We searched the Cochrane Airways Group COPD trials register using pre-specified terms. We also conducted additional handsearches of conference abstracts. The last round of searches were performed in April 2006.

SELECTION CRITERIA

Only randomised controlled trials assessing the effects of injectable pneumococcal vaccine in people with COPD were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and three review authors independently assessed trial quality.

MAIN RESULTS

Although 10 studies cited in 11 publications were identified that met the inclusion criteria for this review, only four of these provided data on participants with COPD. The studies which did provide data for this review consisted of two trials using a 14-valent vaccine, and two using a 23-valent injectable vaccine. Data for the primary outcome, acute exacerbation of COPD, was available from only one of the four studies. The odds ratio of 1.43 (95% confidence interval (CI) 0.31 to 6.69) between interventions was not statistically significant. Of the secondary outcomes for which data were available and could be extracted, none reached statistical significance. Three studies provided dichotomous data for persons who developed pneumonia (OR 0.89, 95% CI 0.58 to 1.37, n = 748). Rates of hospital admissions and emergency department visits came from a single study. There was no significant reduction in the odds of all-cause mortality 1 to 48 months post-vaccination (Peto odds ratio 0.94, 95% CI 0.67 to 1.33, n = 888), or for death from cardiorespiratory causes (OR 1.07, 95% CI 0.69 to 1.66).

AUTHORS' CONCLUSIONS

There is no evidence from randomised controlled trials that injectable pneumococcal vaccination in persons with COPD has a significant impact on morbidity or mortality. Further large randomised controlled trials would be needed to ascertain if the small benefits suggested by individual studies are real.

Treatment of acute exacerbation of severe-to-very severe COPD with azithromycin in patients vaccinated against Streptococcus pneumoniae

Sixty-five consecutive eligible adult patients, who were treated as outpatients for stable severe-to-very severe COPD, were enrolled in the study. All of them received 23-valent pneumococcal capsular polysaccharide vaccine intramuscularly. Patients were seen monthly, as well as whenever they had symptoms suggestive of an exacerbation, at our outpatient clinic. Eighteen out of 65 patients suffered from acute exacerbation (AECOPD). Three of these patients presented two episodes of AECOPD. Patients with an acute exacerbation of COPD received azithromycin 500 mg/day once daily for 3 days and a short course of oral prednisolone 25 mg/die. In 16 cases, a single species was isolated, while in the remaining 5 cases at least two species were recovered. Clinical cure or improvement at the end of therapy (3-5 days post-therapy) was reported in 17 episodes of AECOPD with no relapse at the late post-therapy (10-14 days after the completion of treatment). Bacteriologic eradication or presumptive eradication rates at the end of therapy were 86% (24 out of 28 isolates). Azithromycin eradicated all isolates of Haemophilus influenzae, Moraxella catarrhalis, H. parainfluenzae, Klebsiella pneumoniae, and Klebsiella spp. isolated at baseline. Eradication of Sta aureus occurred in 1 of 3 isolates whereas azithromycin was unable to eradicate Pseudomonas aeruginosa isolates. Our data seem to indicate that pneumococcal vaccination reduces the possibility that an AECOPD is caused by Streptococcus pneumoniae. This finding allows the use of antibiotics such as azithromycin, which, otherwise, should be avoided because of resistances.

[Acute exacerbation of COPD]

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) often develop into emergency situations that are associated with high morbidity and mortality. There is still a lack of a generally accepted definition for the risk stratification in AECOPD to guide an optimal diagnosis and treatment. In this article we propose a classification based on 4 degrees of severity, depending on whether outpatient treatment can be done by the patient himself or is provided by a physician and whether inpatient treatment is carried out on a general ward or on an intensive care unit. The pharmacological therapy of AECOPD relies on short acting bronchodilators, systemic corticosteroids and in case of purulent sputum on antibiotics. Longacting beta(2)-agonists or anticholinergics, theophyllin, mucolytic drugs or mechanical percussion to the chest by a physiotherapist have no proven value in the emergency treatment of AECOPD. In respiratory failure the use of oxygen therapy and non-invasive positive pressure ventilation (NIPPV) can often prevent the need for endotracheal intubation and controlled mechanical ventilation, thus preventing associated risks like the development of nosocomial pneumonia.

New therapies for chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the most common lung disease, carrying a significant mortality and morbidity. None of the therapeutic interventions currently available alter the progression of the disease. As our understanding of the basic mechanisms of alveolar destruction and airflow limitation improves, new targets are identified that may eventually result in treatment options which will affect the progression of this disease. In this review, we discuss some of the novel therapeutic options recently developed that may have an impact on the management of COPD. Future directions in research and development of pharmacological agents based on improved understanding of COPD are also discussed.

Host-pathogen interaction during pneumococcal infection in patients with chronic obstructive pulmonary disease

Acute exacerbation is a frequent complication of chronic obstructive pulmonary disease (COPD). Recent studies suggested a role for bacteria such as Streptococcus pneumoniae in the development of acute exacerbation. For this study, we investigated the following in COPD patients: (i) the epidemiology of pneumococcal colonization and infection, (ii) the effect of pneumococcal colonization on the development of exacerbation, and (iii) the immunological response against S. pneumoniae. We cultured sputa of 269 COPD patients during a stable state and during exacerbation of COPD and characterized 115 pneumococcal isolates by use of serotyping. Moreover, we studied serum immunoglobulin G (IgG) antibody titers, antibody avidities, and functional antibody titers against the seven conjugate vaccine serotypes in these patients. Colonization with only pneumococci (monocultures) increased the risk of exacerbation, with a hazard ratio of 2.93 (95% confidence interval, 1.41 to 6.07). The most prevalent pneumococcal serotypes found were serotypes 19F, 3, 14, 9L/N/V, 23A/B, and 11. We calculated the theoretical coverage for the 7- and 11-valent pneumococcal vaccines to be 60 and 73%, respectively. All patients had detectable IgG levels against the seven conjugate vaccine serotypes. These antibody titers were significantly lower than those in vaccinated healthy adults. Finally, on average, a 2.5-fold rise in serotype-specific and functional antibodies in S. pneumoniae-positive sputum cultures was observed during exacerbation. Our data indicate that pneumococcal colonization in COPD patients is frequently caused by vaccine serotype strains. Moreover, pneumococcal colonization is a risk factor for exacerbation of COPD. Finally, our findings demonstrate that COPD patients are able to mount a significant immune response to pneumococcal infection. COPD patients may therefore benefit from pneumococcal vaccination.