Lung mucosal immunity to NTHi vaccine antigens: Antibodies in sputum of chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory illness in older adults. A major cause of COPD-related morbidity and mortality is acute exacerbation of COPD (AECOPD). Bacteria in the lungs play a role in exacerbation development, and the most common pathogen is non-typeable Haemophilus influenzae (NTHi). A vaccine to prevent AECOPD containing NTHi surface antigens was tested in a clinical trial. This study measured IgG and IgA against NTHi vaccine antigens in sputum. Sputum samples from 40 COPD patients vaccinated with the NTHi vaccine were collected at baseline and 30 days after the second dose. IgG and IgA antibodies against the target antigens and albumin were analyzed in the sputum. We compared antibody signals before and after vaccination, analyzed correlation with disease severity and between sputum and serum samples, and assessed transudation. Antigen-specific IgG were absent before vaccination and present with high titers after vaccination. Antigen-specific IgA before and after vaccination were low but significantly different for two antigens. IgG correlated between sputum and serum, and between sputum and disease severity. Sputum albumin was higher in patients with severe COPD than in those with moderate COPD, suggesting changes in transudation played a role. We demonstrated that immunization with the NTHi vaccine induces antigen-specific antibodies in sputum. The correlation between IgG from sputum and serum and the presence of albumin in the sputum of severe COPD patients suggested transudation of antibodies from the serum to the lungs, although local IgG production could not be excluded.Clinical Trial Registration: NCT02075541.

What is the context? Chronic obstructive pulmonary disease (COPD) is the most common chronic respiratory illness in older adults and the third leading cause of death worldwide.One bacterium in the lungs, non-typeable Haemophilus influenzae (NTHi), is responsible for acute exacerbation of the disease, characterized by an increase in airway wall inflammation and symptoms, leading to high morbidity and mortality.A vaccine targeting NTHi was previously developed but did not show efficacy in reducing exacerbations in COPD patients, probably because the vaccine did not elicit an immune response in the lung mucosae, where the bacteria are located.What is the impact? Parenteral immunization with new vaccines targeting NTHi is able to elicit immune defense at the level of lung mucosae.Now that antibodies can be measured in sputum, new vaccines against COPD exacerbations or other lung infections can be tested for efficacy in the actual target tissue.Also, lung immunity against specific pathogens can now be tested.What is new? We determined that antigen-specific antibodies were present in the lungs after vaccination; these were assessed in sputum after vaccination with NTHi surface antigens.NTHi-specific IgG were present in the lungs and appeared to have arrived there primarily by transudation, a type of leakage from the serum to the lung mucosae.Transudation appeared to be stronger in severe than in moderate COPD patients.

A detailed analysis of possible efficacy signals of NTHi-Mcat vaccine against severe COPD exacerbations in a previously reported randomised phase 2b trial.

BACKGROUND: An investigational vaccine containing non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) surface proteins did not show vaccine efficacy (VE) against combined moderate and severe (moderate/severe) exacerbations in a randomised, observer-blinded, placebo-controlled phase 2b trial of patients with chronic obstructive pulmonary disease (COPD). Nevertheless, observations on rates of severe exacerbations and hospitalisations encouraged further evaluation. METHODS: Patients with stable COPD (moderate to very severe airflow limitation, Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage 2-4), 40-80 years and at least one moderate/severe exacerbation in the last year received two doses of NTHi-Mcat vaccine or placebo plus standard care. Secondary analyses were conducted on VE against exacerbations according to severity. Potential predictive factors at baseline for VE against severe exacerbations were explored in post-hoc analyses. RESULTS: Of 606 patients enrolled, 571 were included in the efficacy analysis (279 in NTHi-Mcat vaccine group, 292 in placebo group). VE against severe acute exacerbations of COPD (AECOPD) in various subgroups was 52.11 % (p = 0.015; frequent exacerbators), 65.43 % (p = 0.015; baseline GOLD grade 4), 38.24 % (p = 0.034; previous pneumococcal and/or influenza vaccination). VE was 52.49 % (p = 0.044) for the 6-12 months period after 1 month post-dose 2. Multivariable analysis identified two factors (frequent exacerbator status plus inhaled corticosteroid use at baseline) associated with significant VE against severe AECOPD; in this subpopulation, VE was 74.99 % (p < 0.001). CONCLUSION: Results suggest potential efficacy with the NTHi-Mcat vaccine against severe exacerbations in certain patients with COPD, in particular those who have frequent exacerbations and use inhaled corticosteroids. This potential signal requires confirmation in an appropriately designed prospective clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03281876.

Non-typeable Haemophilus influenzae-Moraxella catarrhalis vaccine for the prevention of exacerbations in chronic obstructive pulmonary disease: a multicentre, randomised, placebo-controlled, observer-blinded, proof-of-concept, phase 2b trial.

BACKGROUND: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are associated with changes in the sputum microbiome, including an increased prevalence of pathogenic bacteria. Vaccination against the most frequent bacteria identified in AECOPD might reduce exacerbation frequency. We assessed the efficacy, safety, and immunogenicity of a candidate vaccine containing surface proteins from non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) in patients with COPD. METHODS: This multicentre, randomised, observer-blinded, placebo-controlled, proof-of-concept, phase 2b trial recruited patients with stable COPD, moderate-to-very severe airflow limitation (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage 2, 3, or 4), at 67 clinical sites in Belgium, Canada, France, Germany, Italy, Spain, UK, and USA. Eligible patients were aged 40-80 years and had a history of at least one moderate or severe exacerbation in the previous year. Patients were allocated (1:1) using a minimisation algorithm to receive two intramuscular injections of NTHi-Mcat vaccine or placebo 60 days apart, in addition to standard care. The allocation algorithm considered age category, number of previous exacerbations, COPD severity at study entry, and country as minimisation factors, to guarantee treatment balance within each factor. Vaccine recipients and those responsible for evaluating study endpoints were masked to group allocation. In the analysis of efficacy, the primary outcome was the rate of any moderate or severe AECOPD occurring within a 1-year period, starting 1 month after the second dose in patients who received two vaccine doses (modified total vaccinated cohort). Safety was assessed in the total vaccinated cohort. The trial is registered with ClinicalTrials.gov, number NCT03281876, and is complete. FINDINGS: Between Nov 27, 2017, and Nov 30, 2018, 606 adults were enrolled and included in the total vaccinated cohort (304 in the NTHi-Mcat vaccine group, 302 in the placebo group); 571 received two doses and were included in the primary efficacy analysis (279 in the NTHi-Mcat vaccine group, 292 in the placebo group). 23 participants dropped-out in the NTHi-Mcat vaccine group and 39 in the placebo group; this included 4 patients in the NTHi-Mcat vaccine group and 15 in the placebo group who withdrew from the study because of an adverse event. The primary analysis included 340 exacerbations (in follow-up time 102 123 days) in the NTHi-Mcat vaccine group and 333 (in 104 443 days) in the placebo group, with a yearly rate of moderate or severe AECOPD of 1·22 in the NTHi-Mcat vaccine group and 1·17 in the placebo group, with vaccine efficacy in reducing the yearly rate of moderate or severe AECOPD estimated to be zero (vaccine efficacy point estimate 2·26% [87% CI -18·27 to 11·58]; p=0·82). Solicited local adverse events were more frequent in the NTHi-Mcat vaccine group (216 [72%] of 301 patients) than with placebo (34 [11%] of 299 patients), and the frequency of solicited general adverse events was similar between groups (239 [79%] of 301 vs 235 [79%] of 299 patients). There was one death in the NTHi-Mcat vaccine group (acute respiratory failure, not related to vaccination) and ten in the placebo group (seven due in part to COPD or respiratory failure). There were 158 serious adverse events (89 [29%] of 304 patients) in the NTHi-Mcat vaccine group, not related to vaccination, and 214 (99 [33%] of 302 patients) in the placebo group. INTERPRETATION: NTHi-Mcat vaccine administered to patients with COPD did not show efficacy in reducing the yearly rate of moderate or severe exacerbations. No safety concerns were identified. FUNDING: GlaxoSmithKline Biologicals SA.

Results from a large post-marketing safety surveillance study in the Republic of Korea with a quadrivalent meningococcal CRM-conjugate vaccine in individuals aged 2 months-55 years.

The quadrivalent meningococcal conjugate vaccine MenACWY-CRM is approved in the Republic of Korea for use in individuals from 2 months of age. This single-arm, open-label, observational, multicenter, post-marketing study (NCT01766206) assessed the safety of MenACWY-CRM vaccine administered according to local clinical practice. A total of 3939 individuals aged 2 months-55 years provided safety data post-vaccination; the analysis was conducted on the per-protocol set (3920 participants). Solicited and unsolicited adverse events (AEs) were collected over 7 days post-vaccination and medically-attended AEs (MAAEs) and serious AEs (SAEs) over 29 days post-vaccination. Among recorded solicited AEs, injection site AEs were reported by 21.38% of participants, with tenderness/pain being most frequent across age groups; systemic AEs were reported in 13.95% of participants, with irritability (in ˂6-year-olds), headache and myalgia (in ≥6 year-olds) being the most frequently reported. Most solicited AEs were mild or moderate in nature. The percentage of participants reporting unsolicited AEs varied in the study population, i.e. 12.56% in participants aged 2-23 months and 3.18% in those ≥2 years of age. Overall, less than 22% of unsolicited AEs were considered as related to vaccination. MAAEs (10.89% of participants) were mostly mild; 2.82% were considered as related to vaccination. Three (0.46%) and 5 (0.15%) SAEs (none vaccination-related) occurred in participants aged 2-23 months and 2-55 years, respectively. No deaths were reported. The safety profile for MenACWY-CRM in this post-marketing surveillance was consistent with observations from studies conducted during the vaccine's clinical development, with no new safety concerns.

Safety and immunogenicity of non-typeable Haemophilus influenzae-Moraxella catarrhalis vaccine.

Non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) are frequent pathogens in acute exacerbations of COPD. We assessed the safety, reactogenicity and immunogenicity of different investigational vaccine formulations containing surface proteins of NTHi (PD and PE-PilA) and Mcat (UspA2) in adults with smoking history ≥10 pack-years, to immunologically represent the COPD population. Participants received two doses 60 days apart in a randomised, observer-blind, placebo-controlled study (NCT02547974). In step 1, 30 healthy adults aged 18-40 years were randomised (1:1) to receive a non-adjuvanted formulation (10-10-PLAIN) or placebo. In step 2, 90 smokers/ex-smokers aged 50-70 years randomly (1:1:1) received an AS01-adjuvanted formulation containing either 10 µg of each antigen (10-10-AS01) or 10 µg of each NTHi antigen and 3.3 µg of Mcat antigen (10-3-AS01), or placebo. Incidences of solicited local adverse events (AEs) tended to be highest in the AS01-adjuvanted vaccine groups. Most solicited AEs had mild/moderate intensity. No vaccine-related serious AEs were reported. The 10-3-AS01 formulation induced the best humoral immune response against the NTHi antigens. Responses against the Mcat antigen were similar across groups, with waning immunogenicity after 30 days post-dose 2. The investigational NTHi-Mcat vaccine had an acceptable safety and reactogenicity profile and good immunogenicity in older adults with a smoking history.

Second five-year follow-up after a booster vaccination against tick-borne encephalitis following different primary vaccination schedules demonstrates at least 10 years antibody persistence.

BACKGROUND: Tick borne encephalitis (TBE) endemic zones are expanding. We previously evaluated long term persistence of antibody 5 years after the first booster immunization following different primary immunization schedules with the polygeline-free inactivated TBE vaccine (TBEvac) in adults and adolescents. Here, we report anti-TBE virus (TBEV) antibody persistence from 6 to 10 years post-booster administration. METHODS: This was a phase IV, open-label, single-center, second extension study (NCT01562444), conducted in Czechia. Healthy adults and adolescents ≥12 years who had received 3 different primary vaccination schedules (rapid, conventional and accelerated conventional) in the parent study and a booster dose before (12-18 months post-primary series completion) or at the beginning (3 years post-primary series completion) of the first extension study were screened and enrolled in this study. Blood samples were collected yearly and anti-TBEV antibody response was evaluated by neutralizing test (NT) antibody assays. Analysis was performed overall and per age strata: 15-49 years, ≥50 years, and ≥60 years. RESULTS: Of 206 screened individuals, 191 completed the study. Overall, 90-100% of participants in the all-screened set and ≥97% in the per-protocol set had the clinically meaningful threshold of protection (NT titers ≥10) across all timepoints, regardless of the primary vaccination schedule. Overall, antibody geometric mean titers (GMTs) varied from 134 to 343 in the all-screened set. Older age groups showed overall lower GMTs, although GMTs remained higher than NT titers ≥10 up to year 10 in all groups. CONCLUSION: This study showed long-term persistence of anti-TBEV NT antibodies for up to 10 years after the first booster dose of TBEvac in all age groups, regardless of the primary vaccination schedule.

A phase I, randomized, controlled, dose-ranging study of investigational acellular pertussis (aP) and reduced tetanus-diphtheria-acellular pertussis (TdaP) booster vaccines in adults.

Despite high vaccination coverage worldwide, pertussis has re-emerged in many countries. This randomized, controlled, observer-blind phase I study and extension study in Belgium (March 2012-June 2015) assessed safety and immunogenicity of investigational acellular pertussis vaccines containing genetically detoxified pertussis toxin (PT) (NCT01529645; NCT02382913). 420 healthy adults (average age: 26.8 ± 5.5 years, 60% female) were randomized to 1 of 10 vaccine groups: 3 investigational aP vaccines (containing pertussis antigens PT, filamentous hemagglutinin [FHA] and pertactin [PRN] at different dosages), 6 investigational TdaP (additionally containing tetanus toxoid [TT] and diphtheria toxoid [DT]), and 1 TdaP comparator containing chemically inactivated PT. Antibody responses were evaluated on days 1, 8, 30, 180, 365, and approximately 3 years post-booster vaccination. Cell-mediated immune responses and PT neutralization were evaluated in a subset of participants in pre-selected groups. Local and systemic adverse events (AEs), and unsolicited AEs were collected through day 7 and 30, respectively; serious AEs and AEs leading to study withdrawal were collected through day 365 post-vaccination. Antibody responses against pertussis antigens peaked at day 30 post-vaccination and then declined but remained above baseline level at approximately 3 years post-vaccination. Responses to FHA and PRN were correlated to antigen dose. Antibody responses specific to PT, toxin neutralization activity and persistence induced by investigational formulations were similar or significantly higher than the licensed vaccine, despite lower PT doses. Of 15 serious AEs, none were considered vaccination-related; 1 led to study withdrawal (premature labor, day 364; aP4 group). This study confirmed the potential benefits of genetically detoxified PT antigen. All investigational study formulations were well tolerated.

Threshold-free estimation of functional antibody titers of a group B streptococcus opsonophagocytic killing assay.

Opsonophagocytic killing assays (OPKA) are routinely used for the quantification of bactericidal antibodies in blood serum samples. Quantification of the OPKA readout, the titer, provides the basis for the statistical analysis of vaccine clinical trials having functional immune response endpoints. Traditional OPKA titers are defined as the maximum serum dilution yielding a predefined bacterial killing threshold value, and they are estimated by fitting a dose-response model to the dilution-killing curve. This paper illustrates a novel definition of titer, the threshold-free titer, which preserves biological interpretability while not depending on any killing threshold or on a postulated shape of the dose-response curve. These titers are shown to be more precise than the traditional threshold-based titers when using simulated and experimental group B streptococcus OPKA experimental data. Also, titer linearity is shown to be not measurable when using threshold-based titers, whereas it becomes measurable using threshold-free titers. The biological interpretability and operational characteristics demonstrated here indicate that threshold-free titers are an appropriate tool for the routine analysis of OPKA data.