Karlis Pauksens

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in adults 70 years of age and older previously vaccinated with 23-valent pneumococcal polysaccharide vaccine

BACKGROUND The currently recommended single dose of the 23-valent pneumococcal free polysaccharide vaccine (PPSV23) for adults 65 years of age and older does not provide extended protection into older age. This reflects a significant unmet medical need for alternative strategies to protect older adults against pneumococcal infection, which may be met by the 13-valent polysaccharide conjugate vaccine (PCV13). METHODS We performed a randomized, modified double-blind trial in 936 adults aged 70 years and older who had previously received PPSV23 at least 5 years before study entry and were now vaccinated with PCV13 or PPSV23. At 1 year after enrollment, all subjects received a follow-on dose of PCV13. Anti-pneumococcal opsonophagocytic activity (OPA) titers were measured before and at 1 month after each vaccination. RESULTS Following the enrollment vaccination, OPA titers were significantly greater in the PCV13 group compared to the PPSV23 group for 10 of the 12 serotypes common to both vaccines and to serotype 6A which is unique to PCV13. Responses were noninferior for the other 2 common serotypes. Responses to PCV13 given at 1 year were generally lower in the group that received PPSV23 at enrollment. CONCLUSION In adults aged 70 years and older previously vaccinated with PPSV23, PCV13 was significantly more immunogenic than PPSV23 for most of the common serotypes and for serotype 6A. The OPA responses after a follow-on dose of PCV13 one year later indicate that a prior dose of PPSV23, but not PCV13, diminishes the response to the subsequent administration of PCV13.

Correlation between Serum TNFα and IL6 levels and Severity of Group: A Streptococcal Infections

The multiorgan failure syndrome caused by group A streptococci (GAS) designated streptococcal toxic shock syndrome (STSS) is believed to be mediated by cytokines induced by superantigens. In order to study the relationship between superantigen production, cytokine levels in patient sera, and clinical GAS manifestation we examined acute-phase sera and strains from 25 patients with GAS bacteremia. The patients had various disease manifestations, including STSS (44%), erysipelas (28%), septicemia (24%), wound infections (16%), and pneumonia (12%). Serotype T1M1 dominated, representing 56% of the isolates, but also strains of other serotypes were identified. The strains were found to produce the streptococcal pyrogenic exotoxins (Spe) A, B, and F, as determined by immuno-blot analyses. There was no difference in amounts of toxin produced between strains isolated from patients with different manifestations of disease. Levels of TNF alpha, IL1 alpha, IL6, IL8, and IFN gamma in acute-phase sera were determined by use of ELISA and RIA assays. The analyses showed higher levels of IL6 in sera from patients with STSS than in sera from patients with bacteremia without shock. TNF alpha was elevated in sera from patients with STSS, as compared to sera from patients with uncomplicated pharyngotonsillitis. No increase in the levels of IL1 alpha, IL8, and IFN gamma could be found in the patient sera and there was no difference in the level of those cytokines between the various patient categories.

Post-transplant lymphoproliferative disease and other Epstein-Barr virus diseases in allogeneic haematopoietic stem cell transplantation after introduction of monitoring of viral load by polymerase chain reaction

The clinical value of monitoring of Epstein-Barr virus (EBV) viraemia by quantitative polymerase chain reaction during 1 y was evaluated. 39 recipients of allogeneic hematopoietic stem cell transplantation (SCT) were followed. More than 100 EBV genome equivalents (gEq)/ml in blood or plasma were found in 16/39 patients (41%) at 34 d (range 1–139) post-transplant. Seven of these 16 patients developed EBV disease; 3 post-transplant lymphoproliferative disease (PTLD), 1 myelitis, 1 encephalitis and 2 reactivations with fever. EBV diseases were only found in the high-risk group among recipients of mismatched related or unrelated donor grafts or in patients who underwent reduced-intensity conditioning. In this group, 3/20 (15%) developed PTLD. Conditioning with antithymocyte globulin was significantly associated with EBV disease (p<0.01). EBV load in plasma was more strongly associated with EBV disease than viral load in blood. A cut-off level of 1000 gEq/ml plasma distinguished EBV disease from asymptomatic viraemia, but not PTLD from other EBV diseases. Weekly monitoring of EBV load in plasma in high-risk patients in the first 3 months following SCT seems to be of value for prediction of EBV disease. Therapy for PTLD including rituximab was evaluated during 2 y and showed response in 4/6 cases.

Safety and immunogenicity of three different formulations of an adjuvanted varicella-zoster virus subunit candidate vaccine in older adults: A phase II, randomized, controlled study

BACKGROUND This study investigated the safety and immunogenicity of different formulations and schedules of a candidate subunit herpes zoster vaccine containing varicella-zoster virus glycoprotein E (gE) with or without the adjuvant system AS01B. METHODS In this phase II, single-blind, randomized, controlled study, adults aged ≥60years (N=714) received one dose of 100μggE/AS01B, two doses, two months apart, of 25, 50, or 100μggE/AS01B, or two doses of unadjuvanted 100μggE/saline. Frequencies of CD4(+) T cells expressing ≥2 activation markers following induction with gE were measured by intracellular cytokine staining and serum anti-gE antibody concentrations by ELISA. RESULTS Frequencies of gE-specific CD4(+) T cells were >3-fold higher after two doses of all gE/AS01B formulations than after one dose of 100μggE/AS01B or two doses of 100μggE/saline. Frequencies were comparable after two doses of 25, 50, or 100μggE/AS01B. Serum anti-gE antibody concentrations were comparable after two doses of 50 or 100μggE/AS01B and higher than in the other groups. Immune responses persisted for at least 36 months. Reactogenicities of all gE/AS01B formulations were similar but greater than with gE/saline. CONCLUSIONS The three formulations of gE/AS01B were immunogenic and well tolerated in adults aged ≥60years. Two vaccinations with gE/AS01B induced higher immune responses than one and the dose of gE impacted humoral but not cellular immune responses (NCT00434577).

Long-term immunogenicity and safety of an investigational herpes zoster subunit vaccine in older adults.

BACKGROUND An investigational subunit vaccine containing the varicella-zoster virus (VZV) glycoprotein E (gE) and the AS01B adjuvant system is being evaluated for the prevention of herpes zoster (HZ) in older adults. A phase II trial evaluating different formulations of this vaccine (containing 25μg, 50μg, or 100μg gE) was conducted in adults ≥60 years of age and showed that all formulations elicited robust cellular and humoral immune responses for up to 3 years after vaccination. In this follow-up study in subjects who received two doses of the 50μg gE/AS01B formulation (HZ/su), we assessed the persistence of the immune responses for up to 6 years after vaccination. METHODS This phase II, open-label, multicenter, single-group trial conducted in the Czech Republic, Germany, Sweden, and the Netherlands followed 129 subjects who had received two doses (2 months apart) of HZ/su during the initial trial. Vaccine-induced immune responses (frequencies of gE-specific CD4(+) T cells expressing ≥2 activation markers and serum anti-gE antibody concentrations) were evaluated at 48, 60, and 72 months after the first HZ/su dose. RESULTS Six years after vaccination with HZ/su, gE-specific cell-mediated immune responses and anti-gE antibody concentrations had decreased by 20-25% from month 36, but remained higher than the prevaccination values. At month 72, the gE-specific cell-mediated immune response was 3.8 times higher than the prevaccination value (477.3 vs. 119.4 activated gE-specific CD4(+) T cells per 10(6) cells), and the anti-gE antibody concentration was 7.3 times higher than the prevaccination value (8159.0 vs. 1121.3mIU/mL). No vaccine-related serious adverse events were reported between months 36 and 72. CONCLUSIONS gE-specific cellular and humoral immune responses persisted for 6 years after two-dose vaccination with HZ/su in healthy older adults. No safety concerns were identified.

Neutrophil CD64 (FcγRI) expression is a specific marker of bacterial infection: A study on the kinetics and the impact of major surgery

Neutrophil CD64 expression is a diagnostic marker for the early detection of bacterial infections. The aim was to investigate the kinetics of neutrophil CD64 expression during bacterial infection and the possible impact of surgical trauma. Blood samples were collected daily during 3 d after admission for analysis by flow cytometry of the surface expressions on neutrophils and monocytes of CD64, CD16, CD32, CD11b/CD18 and CD35, and analysis of serum CRP and blood WBC. Serum concentrations of IFNγ, G-CSF, IL-6 and IL-8 were also analysed in adults. Eight children and 19 adult patients with bacterial infections, 12 patients admitted for hip-arthroplasty because of coxarthrosis and 30 healthy adults were studied. Neutrophil CD64 was increased all 3 d after start of treatment (p<0.0001) in children and adults with bacterial infections. The postoperative increase after surgery was less than the increase seen during bacterial infections (p<0.0001). CRP, G-CSF, IL-6 and IL-8 were raised both in bacterial infections and after surgery. Our results indicate that the expression of CD64 on neutrophils is a specific sign of bacterial infections. Neutrophil expression of CD64, therefore, seems to be a promising tool for the early detection of bacterial infections even during surgery.

Immune response to the 23-valent polysaccharide pneumococcal vaccine after the 7-valent conjugate vaccine in allogeneic stem cell transplant recipients : Results from the EBMT IDWP01 trial

The current recommendations for active immunization after stem cell transplant (SCT) include 3 doses of 7-valent pneumococcal conjugate vaccine (PCV7) from 3 months after transplant, followed by a 23-valent polysaccharide pneumococcal vaccine (PPV23). However, until now, the immune response to PPV23 after PCV7 has not been assessed after SCT. In the EBMT IDWP01 trial, 101 patients received 1 dose of PPV23 at 12 or 18 months, both after 3 doses of PCV7. The efficacy of PPV23 was assessed 1 month later and at 24 months after transplant by the pneumococcal serotype 1 and 5 antibody levels. Serotype 1 and 5 are not included in PCV7. Although the geometric mean concentrations were significantly higher 1 month after PPV23, for both antigens, the response rates (> or =0.15 microg/mL), in the range of 68-94%, were not different between groups independent of the assessment date. One PPV23 dose after 3 PCV7 doses, already known to increase the response to PCV7, also extends the serotype coverage given 12 or 18 months after transplant.

A population-based study of 135 lymphomas after solid organ transplantation: The role of Epstein-Barr virus, hepatitis C and diffuse large B-cell lymphoma subtype in clinical presentation and survival.

Abstract Background. Epstein-Barr virus (EBV) plays a major role in the development of post-transplant lymphoproliferative disorder (PTLD), but there is an increasing awareness of EBV-negative PTLD. The clinical presentation of EBV-negative PTLD has not been as well characterised as EBV-positive cases. Further, there is limited knowledge on the clinical importance of diffuse large B-cell lymphoma (DLBCL) cell of origin subtype post-transplant. Materials and methods. We studied the role of EBV, hepatitis C (HCV) and DLBCL subtype in clinical presentation and survival in 135 post-transplant lymphomas diagnosed 1980–2006 in a population-based cohort of 10 010 Swedish solid organ transplant recipients. The lymphomas were re-evaluated according to WHO 2008, examined for EBV, and clinical data were collected from medical records. Results. Lymphoma incidence rate was 159/100 000 person-years and is also reported by lymphoma subtype. EBV-negative lymphomas constituted 48% and were associated with HCV infection (p = 0.02), bone marrow involvement (p < 0.001), and T-cell phenotype (p = 0.002). Among DLBCL, 78% were of non-germinal centre subtype, which was associated with EBV-positivity (69%, p = 0.001), early occurrence (p = 0.03), heart/liver/lung/pancreas recipients (p = 0.02), anti-T-cell globulin (p = 0.001), and tacrolimus treatment (p = 0.02). DLBCL subtypes had similar overall survival. Five-year overall survival was 42% in all treated patients. Independent poor prognostic factors were older age, B symptoms, ECOG 2-4, kidney/pancreas/heart recipients, T-cell lymphoma, and HCV-infection. Conclusions. With long follow-up, a large part of PTLD is EBV-negative, due to a high proportion of T-cell lymphomas and low of polymorphic PTLD. EBV-negative PTLD have a different clinical presentation. HCV may play an aetiological role in late-onset PTLD and was revealed as a new prognostic factor for inferior survival that needs to be confirmed in larger studies. The heavier immunosuppression in non-kidney transplantations seems to play a role in the development of non-germinal centre DLBCL. DLBCL cell of origin subtype lacks prognostic importance in the transplant setting.

Selection of an adjuvant for seasonal influenza vaccine in elderly people: modelling immunogenicity from a randomized trial

BackgroundImproved influenza vaccines are needed to reduce influenza-associated complications in older adults. The aim of this study was to identify the optimal formulation of adjuvanted seasonal influenza vaccine for use in elderly people.MethodsThis observer-blind, randomized study assessed the optimal formulation of adjuvanted seasonal influenza vaccine based on immunogenicity and safety in participants aged ≥65 years. Participants were randomized (~200 per group) to receive one dose of non-adjuvanted vaccine or one of eight formulations of vaccine formulated with a squalene and tocopherol oil-in-water emulsion-based Adjuvant System (AS03C, AS03B or AS03A, with 2.97, 5.93 and 11.86 mg tocopherol, respectively) together with the immunostimulant monophosphoryl lipid A (MPL, doses of 0, 25 or 50 mg). Hemagglutination-inhibition (HI) antibody responses and T-cell responses were assessed on Day 0 and 21 days post-vaccination. The ratio of HI-based geometric mean titers in adjuvanted versus non-adjuvanted vaccine groups were calculated and the lower limit of the 90% confidence interval was transformed into a desirability index (a value between 0 and 1) in an experimental domain for each vaccine strain, and plotted in relation to the AS03 and MPL dose combination in the formulation. This model was used to assess the optimal formulation based on HI antibody titers. Reactogenicity and safety were also assessed. The immunogenicity and safety analyses were used to evaluate the optimal formulation of adjuvanted vaccine.ResultsIn the HI antibody-based model, an AS03 dose–response was evident; responses against the A/H1N1 and A/H3N2 strains were higher for all adjuvanted formulations versus non-adjuvanted vaccine, and for the AS03A-MPL25, AS03B-MPL25 and AS03B-MPL50 formulations against the B strain. Modelling using more stringent criteria (post hoc) showed a clear dose-range effect for the AS03 component against all strains, whereas MPL showed a limited effect. Higher T-cell responses for adjuvanted versus non-adjuvanted vaccine were observed for all except two formulations (AS03C and AS03B-MPL25). Reactogenicity increased with increasing AS03 dosage, and with MPL. No safety concerns were raised.ConclusionsFive formulations containing AS03A or AS03B were identified as potential candidates to improve immune responses to influenza vaccination; AS03B without MPL showed the best balance between improved immunogenicity and acceptable reactogenicity.Trial registrationThis trial is registered at ClinicalTrials.gov, NCT00540592

The response to vaccination against influenza A(H1N1) 2009, seasonal influenza and Streptococcus pneumoniae in adult outpatients with ongoing treatment for cancer with and without rituximab

Abstract It is debated whether cancer patients treated with chemotherapy can mount an adequate response to vaccination. Material and methods. Ninety-six adult outpatients with cancer, who were undergoing chemotherapy and/or monoclonal antibody, tyrosine kinase inhibitor, irradiation or corticosteroid treatments, were studied. Two doses of the pandemic influenza A(H1N1)/09 AS03-adjuvanted split virion vaccine, one dose of the seasonal influenza vaccine and one dose of the 23-valent pneumococcal polysaccharide vaccine were given. Serum haemagglutination inhibition (HI) assays were used to determine antibody titres against the influenza strains. For the pneumococcal vaccine 14 different serotype-specific anti-capsular antibodies were measured by bead assay xMAP®. Results. Patients treated with rituximab did not respond to vaccination. For patients without rituximab treatment 4% had putatively protective antibodies before vaccination (HI ≥ 40) to the pandemic-like strain A/California7/2009HINI. After the first and second dose of vaccine, seroprotection rates (SPR) were 62% and 87%, and seroconversion rates (SCR) 62% and 84%, respectively. Before seasonal flu vaccination SPR against influenza A/Brisbane/59/2007H1N1 and A/Uruguay/10/2007H3N2 were 19% and 17%, respectively. After vaccination, SPR were 70% and 59% and SCR 42% and 50%, respectively. For the pneumococcal vaccine protective antibodies were found to 40% of the 14 strains before and to 68% after vaccination. The mean response to pneumococcal vaccination was to 44% of the 14 serotypes. A response to at least 50% of the 14 serotypes was found in 49% of the patients. No serious adverse events were reported. Conclusion. A substantial number of adult cancer patients with ongoing chemotherapy treatment could mount an adequate serological response to influenza and pneumococcal vaccination without severe adverse events. Thus, vaccination should be recommended. Adjuvanted vaccines may improve the vaccine response among this patient group. Patients recently treated with rituximab do not respond to vaccination.