In the vaccinated groups, GMRs at each time point were higher than or equal to 3

In the vaccinated groups, GMRs at each time point were higher than or equal to 3.4 (95% CI: 2.54.8) for PD, 23.2 (15.734.3) for PE and 4.4 (3.16.3) for PilA (Fig. (UspA2) surface proteins. In a randomised, observer-blind, placebo-controlled study with two steps (NCT02547974), the investigational vaccine had good immunogenicity and no safety concerns were identified. In step 2 2, 90 adults aged 5071 years with smoking history received two doses 60 days apart of one of two AS01E-adjuvanted formulations containing 10 g of each antigen (1010-AS01) or 10 g NTHi antigens and 3.3 g UspA2 (103-AS01), or placebo. Long-term persistence of antigen-specific humoral antibodies was assessed in 81 participants during 3 years Gepotidacin of follow-up after the initial 14-month study (NCT03201211). Antigen-specific antibody concentrations were measured in blood samples taken every 6 months. Safety monitoring evaluated serious adverse events (SAEs) and potential immune-mediated disease (pIMD). Immune responses against NTHi antigens Gepotidacin persisted up to 4 years post-vaccination. For PD, PE and PilA, at Gepotidacin each follow-up time point, adjusted antibody geometric mean concentrations (GMCs) were higher (non-overlapping 95% confidence intervals [CIs]) in the vaccine groups versus placebo and versus pre-vaccination. Antibody GMC point estimates were higher with 103-AS01 than with 1010-AS01. For UspA2, 95% CIs included 1 for GMC ratios of 1010-AS01 or 103-AS01 to placebo at each time point. During follow-up, SAEs were reported in nine (11.1%) participants, one of which was fatal (lung cancer, 607 days after second 1010-AS01 dose). One non-serious pIMD, trigeminal neuralgia, was reported 771 days after second 103-AS01 dose. The SAEs and pIMD were considered not related to vaccination. Immune responses against NTHi antigens persisted for 4 years after two-dose vaccination with the investigational NTHi-Mcat vaccine. There was no persistent response against the Mcat antigen. No safety concerns were identified during the long-term follow-up. == Introduction == Chronic obstructive pulmonary disease (COPD) is the third leading cause of death globally[1], with an estimated prevalence of 12% in people aged 30 years or more[2]. Acute exacerbations of COPD (AECOPD) are periods of worsened respiratory symptoms, beyond that seen with day-to-day variation, that increase the risk of myocardial infarction, stroke, pulmonary embolism and death[3]. No vaccine is approved for the prevention of AECOPD, although influenza and pneumococcal vaccines, which are routinely recommended to COPD patients[4], may have some effect on the frequency of exacerbations[5]. Bacterial infection is frequently associated with AECOPD, most commonly non-typeableHaemophilus influenzae(NTHi),Moraxella catarrhalis(Mcat) andStreptococcus pneumoniaeinfections[6],[7],[8],[9]. Targeting the major bacterial species associated with AECOPD may be a viable strategy for vaccine development. There is evidence that NTHi and Mcat can act as co-pathogens in respiratory tract infections and COPD, as indicated by protection of NTHi from complement-mediated killing via complement resistance factors on outer membrane vesicles produced by Mcat[10]. Increased resistance to antibiotics and host clearance also appears to be promoted by NTHi and Mcat co-infection[11],[12]. An adjuvanted multicomponent vaccine has been developed to reduce the frequency of moderate and severe AECOPD associated with NTHi and Mcat. The investigational NTHi-Mcat vaccine contains four surface proteins involved in the virulence mechanisms of both bacterial pathogens[13]. Three are from NTHi, a free recombinant protein D (PD) and a recombinant fusion protein combining protein E and Pilin A (PE-PilA), and the fourth from Mcat, ubiquitous surface protein A2 (UspA2). Evidence from animal studies suggest anti-PD antibodies have opsonic activity[14]and protect againstH. influenzaeinfection[15], while antibodies generated by the PE-PilA fusion protein inhibit the binding of PE to vitronectin (which may protect the bacterium from complement attack[16],[17]) and inhibit the formation of NTHi biofilms[18], as previously described for anti-PilA antibodies[19]. Anti-UspA2 antibodies significantly reduced the lung bacterial load in mice Rabbit polyclonal to ZNF418 challenged with homologous or heterologous Mcat strains[20]and have been shown to be bactericidal and cross-reactive[20],[21]. A vaccine formulation containing the NTHi proteins had an acceptable safety and reactogenicity profile and induced antigen-specific immune responses in phase 1 studies of healthy 1840 year-olds and current and former smokers aged 5070 years[22]. The population group of adults with smoking history was chosen to immunologically match the COPD population, with evidence suggesting that alterations in the immune system start early in smokers, before COPD is diagnosed[23],[24],[25]. NTHi vaccine formulations that included the Adjuvant System AS01E[26]produced the highest humoral and cellular immune responses in older adults[22]. A phase 2 study of the adjuvanted NTHi vaccine in adults with COPD showed no safety concerns and good immunogenicity[27]. In the.