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Featured researches published by Leszek Szenborn.


Lancet Infectious Diseases | 2012

Safety, immunogenicity, and tolerability of meningococcal serogroup B bivalent recombinant lipoprotein 2086 vaccine in healthy adolescents: a randomised, single-blind, placebo-controlled, phase 2 trial

Peter Richmond; Helen Marshall; Michael D. Nissen; Qin Jiang; Kathrin U. Jansen; Maria Garcés-Sánchez; Federico Martinón-Torres; Johannes Beeslaar; Leszek Szenborn; Jacek Wysocki; Joseph Eiden; Shannon L. Harris; Thomas R. Jones; John L. Perez

BACKGROUND Neisseria meningitidis serogroup B is a major cause of invasive meningococcal disease, but a broadly protective vaccine is not currently licensed. A bivalent recombinant factor H-binding protein vaccine (recombinant lipoprotein 2086) has been developed to provide broad coverage against diverse invasive meningococcus serogroup B strains. Our aim was to test the immune response of this vaccine. METHODS This randomised, placebo-controlled trial enrolled healthy adolescents from 25 sites in Australia, Poland, and Spain. Exclusion criteria were previous invasive meningococcal disease or serogroup B vaccination, previous adverse reaction or known hypersensitivity to the vaccine, any significant comorbidities, and immunosuppressive therapy or receipt of blood products in the past 6 months. Participants were randomly assigned with a computerised block randomisation scheme to receive ascending doses of vaccine (60, 120, or 200 μg) or placebo at 0, 2, and 6 months. Principal investigators, participants and their guardians, and laboratory personnel were masked to the allocation; dispensing staff were not. Immunogenicity was measured by serum bactericidal assays using human complement (hSBA) against eight diverse meningococcus serogroup B strains. The co-primary endpoints were seroconversion for the two indicator strains (PMB1745 and PMB17) analysed by the Clopper-Pearson method. Local and systemic reactions and adverse events were recorded. The study is registered at ClinicalTrials.gov, number NCT00808028. FINDINGS 539 participants were enrolled and 511 received all three study vaccinations--116 in the placebo group, 21 in the 60 μg group, 191 in the 120 μg group, and 183 in the 200 μg group. The proportion of participants responding with an hSBA titre equal to or greater than the lower limit of quantitation of the hSBA assays (reciprcocal titres of 7 to 18, depending on test strain) was similar for the two largest doses and ranged from 75·6 to 100·0% for the 120 μg dose and 67·9 to 99·0% for the 200 μg dose. Seroconversion for the PMB1745 reference strain was 17 of 19 (89·5%) participants for the 60 μg dose, 103 of 111 (92·8%) participants for the 120 μg dose, 94 of 100 (94·0%) participants for the 200 μg dose, and four of 73 (5·5%) participants for placebo. For the PMB17 reference strain seroconversion was 17 of 21 (81·0%) participants for the 60 μg dose, 97 of 112 (86·6%) participants for the 120 μg dose, 89 of 105 (84·8%) participants for the 200 μg dose, and one of 79 (1·3%) participants for placebo. The hSBA response was robust as shown by the high proportion of responders at hSBA titres up to 16. Mild-to-moderate injection site pain was the most common local reaction (50 occurrences with the 60 μg dose, 437 with the 120 μg dose, 464 with the 200 μg dose, and 54 with placebo). Systemic events, including fatigue and headache, were generally mild to moderate. Overall, adverse events were reported by 18 participants (81·8%) in the 60 μg group, 77 (38·9%) in the 120 μg group, 92 (47·2%) in the 200 μg group, and 54 (44·6%) in the placebo group. Fevers were rare and generally mild (one in the 60 μg group, 24 in the 120 μg group, 35 in the 200 μg group, and five in the placebo group; range, 0-6·3% after each dose). Incidence and severity of fever did not increase with subsequent vaccine dose within groups. One related serious adverse event that resolved without sequelae occurred after the third dose (200 μg). INTERPRETATION The bivalent recombinant lipoprotein 2086 vaccine is immunogenic and induces robust hSBA activity against diverse invasive meningococcus serogroup B disease strains and the vaccine is well tolerated. Recombinant lipoprotein 2086 vaccine is a promising candidate for broad protection against invasive meningococcus serogroup B disease. FUNDING Wyeth, Pfizer.


Hepatology | 2012

Randomized, placebo‐controlled trial of tenofovir disoproxil fumarate in adolescents with chronic hepatitis B

Karen F. Murray; Leszek Szenborn; Jacek Wysocki; Stephen Rossi; Amoreena Corsa; Phillip Dinh; John G. McHutchison; Phillip S. Pang; Luminita M. Luminos; Małgorzata Pawłowska; Jacek Mizerski

Tenofovir disoproxil fumarate (DF) is highly effective for the suppression of hepatitis B virus (HBV) in chronically infected adults. This study evaluated the safety and efficacy of tenofovir DF in adolescents with chronic hepatitis B (CHB). In this double‐blind, placebo‐controlled trial, adolescents 12 to <18 years of age with CHB were randomized to tenofovir DF 300 mg (n = 52) or placebo (n = 54) once daily for 72 weeks. The primary endpoint was virologic response (HBV DNA <400 copies/mL) at week 72. One hundred six patients were enrolled; 101 patients completed 72 weeks of treatment. At baseline, 91% of patients were hepatitis B e antigen–positive and 85% had prior exposure to HBV therapy. A virologic response was observed in 89% (46/52) of patients who received tenofovir DF and 0% (0/54) of patients who received placebo (P < 0.001). Treatment response was not affected by prior HBV treatment. Furthermore, no resistance to tenofovir DF developed through week 72. Among patients with an alanine aminotransferase (ALT) level greater than the upper limit of normal at baseline, normalization of ALT occurred in 74% of patients receiving tenofovir DF and 31% of patients receiving placebo (P < 0.001). The rate of grade 3/4 adverse events was higher among patients treated with placebo (24%) than patients treated with tenofovir DF (10%). No patients met the safety endpoint of a 6% decrease in spine bone mineral density at week 72. Conclusion: Tenofovir DF therapy in HBV‐infected adolescents was well tolerated and highly effective at suppressing HBV DNA and normalizing ALT values in both treatment‐naïve adolescents and those with prior exposure to HBV therapy. (HEPATOLOGY 2012;56:2018–2026)


Pediatric Infectious Disease Journal | 2012

Safety, Reactogenicity and Immunogenicity of the Human Rotavirus Vaccine in Preterm European Infants: A Randomized Phase IIIb Study

Félix Omeñaca; Jean Sarlangue; Leszek Szenborn; Marta Nogueira; P.V. Suryakiran; Igor Smolenov; Htay Htay Han

Background: Rotavirus disease is more severe in preterm infants than in full-term infants. This study assessed the safety, reactogenicity and immunogenicity of a human rotavirus vaccine, RIX4414, in European preterm infants. Methods: A total of 1009 preterm infants were randomized (2:1, vaccine:placebo) and stratified into 2 groups: 20% of early (27–30 weeks, group 1) and 80% of late (31–36 weeks, group 2) gestational age preterm infants in each group. Two doses of RIX4414/placebo were administered to these preterm infants according to the recommended chronologic age for full-term infants with an interval of 30–83 days between doses. Serious adverse events were recorded throughout the study period. Solicited and unsolicited adverse events were recorded for 15 and 31 days post-each dose. Antirotavirus IgA concentrations (enzyme-linked immunosorbent assay cutoff = 20 U/mL) and geometric mean concentration were determined pre-dose 1 and 30–83 days post-dose 2 in a subset of 300 infants. This study is registered with ClinicalTrials.gov, number NCT00420745 (eTrack106481). Results: Serious adverse events were reported at a similar frequency in both groups (P = 0.266). Fifty-seven infants reported at least 1 serious adverse event (5.1% [3.5–7.0] in the RIX4414 group and 6.8% [4.3–10.0] in the placebo group). During the 15-day postvaccination follow-up period, diarrhea, vomiting and fever occurred at a similar frequency in both groups; fever could have been due to concomitant vaccines. Five cases (RIX4414 = 3, Placebo = 2) of rotavirus gastroenteritis were reported. The onset of rotavirus gastroenteritis in the RIX4414 group was 1–5 days after vaccination (vaccine strain identified in all cases) and in the placebo group it was 3–4 days after receiving placebo (wild-type rotavirus identified from both cases). Antirotavirus IgA seroconversion rates at 30–83 days post-dose 2 were 85.7% (79.0–90.9) in the RIX4414 group and 16.0% (8.8–25.9) in the placebo group. Geometric mean concentrations were 202.2 U/mL (153.1–267.1) in the RIX4414 group and <20 U/mL in the placebo group. Seroconversion rate in groups 1 and 2 in RIX4414 recipients were 75.9% (95% confidence interval [CI]: 56.5–89.7%) and 88.1% (95% CI: 80.9–93.4%), respectively; the geometric mean concentrations in the respective groups were 110.2 U/mL (95% CI: 56.1–216.5) and 234.8 U/mL (95% CI: 173.4–318.0; exploratory analysis). Conclusions: Two doses of RIX4414 were immunogenic and well-tolerated in European preterm infants.


Vaccine | 2015

A comparative evaluation of two investigational meningococcal ABCWY vaccine formulations: Results of a phase 2 randomized, controlled trial

Stan L. Block; Leszek Szenborn; Wendy Daly; Teresa Jackowska; Diego D’Agostino; Linda Han; Peter M. Dull; Igor Smolenov

BACKGROUND A meningococcal vaccine protective against all major disease-associated serogroups (A, B, C, W and Y) is an unmet public health need. In this phase 2 observer-blinded, randomized, controlled study, two investigational meningococcal ABCWY vaccine formulations were evaluated to assess their immunological noninferiority to a licensed quadrivalent meningococcal ACWY glycoconjugate vaccine (MenACWY-CRM) for serogroups ACWY and immunogenicity against serogroup B test strains, as well as for formulation selection based on a desirability index (DI). Each investigational MenABCWY formulation contained recombinant protein and outer membrane vesicle (OMV) components of a licensed serogroup B vaccine (4CMenB) combined with components of MenACWY-CRM. METHODS A total of 484 healthy 10-25 year-old participants were randomized to receive two doses, two months apart, of an investigational MenABCWY formulation that contained either a full or one-quarter dose of OMV, 4CMenB alone, or a Placebo followed by MenACWY-CRM. Immunogenicity against each of serogroups ACWY and four serogroup B test strains was assessed by serum bactericidal assay with human complement (hSBA). MenABCWY formulations were compared by a DI based on key immunogenicity and reactogenicity parameters. RESULTS Seroresponse rates for serogroups ACWY were significantly higher after two doses of either MenABCWY formulation than after one dose of MenACWY-CRM: respectively, A: 90-92% vs. 73%; C: 93-95% vs. 63%; W: 80-84% vs. 65%; and Y: 90-92% vs. 75%. Prespecified noninferiority criteria were met. Both MenABCWY formulations induced substantial immune responses against serogroup B test strains, although 4CMenB responses were higher. Overall DIs for both MenABCWY formulations were similar. Reactogenicity profiles of the MenABCWY formulations were similar to each other and to that of 4CMenB. No vaccine-related serious adverse events were reported. CONCLUSIONS Both investigational MenABCWY formulations elicited robust immune responses against serogroups ACWY and serogroup B test strains, and had acceptable reactogenicity profiles, with no safety concerns identified.


Lancet Infectious Diseases | 2017

Meningococcal serogroup B-specific responses after vaccination with bivalent rLP2086: 4 year follow-up of a randomised, single-blind, placebo-controlled, phase 2 trial

Helen Marshall; Peter Richmond; Johannes Beeslaar; Qin Jiang; Kathrin U. Jansen; Maria Garcés-Sánchez; Federico Martinón-Torres; Leszek Szenborn; Jacek Wysocki; Joseph Eiden; Shannon L. Harris; Thomas R. Jones; Su-San Lee; John L. Perez

BACKGROUND Bivalent rLP2086 is a recombinant factor H binding protein-based vaccine approved in the USA for prevention of meningococcal serogroup B disease in 10-25-year-olds. We aimed to assess the persistence of bactericidal antibodies up to 4 years after a three-dose schedule of bivalent rLP2086. METHODS We did this randomised, single-blind, placebo-controlled, phase 2 trial at 25 sites in Australia, Poland, and Spain. In stage 1 of the study (February, 2009-May, 2010), healthy adolescents (aged 11-18 years) were randomly assigned, via an interactive voice and web-response system with computer-generated sequential random numbers, to receive either ascending doses of vaccine (60 μg, 120 μg, and 200 μg) or placebo at months 0, 2, and 6. Dispensing staff were not masked to group allocation, but allocation was concealed from principal investigators, participants and their guardians, and laboratory personnel. In stage 2 of the study (reported here), we enrolled healthy adolescents who had received three doses of 120 μg bivalent rLP2086 (the optimum dose level identified in stage 1) or saline. Immunogenicity was determined in serum bactericidal antibody assay using human complement (hSBA) by use of four meningococcal serogroup B test strains expressing vaccine-heterologous factor H binding protein variants: PMB80 (A22), PMB2001 (A56), PMB2948 (B24), and PMB2707 (B44). Immunogenicity in stage 2 was assessed at months 6, 12, 24, and 48 post-vaccination. We did analysis by intention to treat. This trial is registered as ClinicalTrials.gov number NCT00808028. FINDINGS Between March 17, 2010, and Feb 8, 2011, 170 participants who received 120 μg of bivalent rLP2086 and 80 participants who received placebo in stage 1 of the study were entered into stage 2; 210 participants completed stage 2 up to 48 months. 1 month after the third vaccination, 93% (n=139/149) to 100% (n=48/48) of vaccine recipients achieved protective hSBA titres equal to or greater than the lower limit of quantification to each test strain, compared with 0% (n=0/25) to 35% (n=8/23) of control recipients. Despite initial declines in seroprotective hSBA titres for all four test strains, for three test strains (A22, A56, and B24), more than 50% of bivalent rLP2086 recipients continued to achieve titres equal to or greater than the lower limit of quantification at months 6 (57% [n=93/163] to 89% [n=42/47]), 12 (54% [n=84/155] to 69% [n=33/48]), 24 (53% [n=26/49] to 54% [n=82/152]), and 48 (51% [n=24/47] to 59% [n=79/134]); corresponding values in the control group were 14% (n=11/80) to 22% (n=5/23) at month 6, 13% (n=10/78) to 29% (n=22/76) at month 12, 16% (n=12/74) to 36% (n=8/22) at month 24, and 24% (n=16/68) to 35% (n=8/23) at month 48. For test strain B44, hSBA titres equal to or greater than the lower limit of quantification were shown in 37% (n=18/49) of vaccine recipients at 6 months, in 29% (n=14/48) at 12 months, in 22% (n=11/49) at 24 months, and in 20% (n=10/49) at 48 months, compared with 0% (n=0/25) of control recipients at month 6, 4% (n=1/25) at months 12 and 24, and 12% (n=3/25) at month 48. Adverse events were reported in seven (4%) of 170 participants in the bivalent rLP2086 group and two (3%) of 80 participants in the control group; no event was deemed related to vaccine. INTERPRETATION After three doses of bivalent rLP2086, protective hSBA titres above the correlate of protection (≥1/4) were elicited up to 4 years in more than 50% of participants for three of four meningococcal serogroup B test strains representative of disease-causing meningococci expressing vaccine-heterologous antigens. Further studies will be needed to assess possible herd immunity effects with meningococcal serogroup B vaccines and the need for a booster dose to sustain individual protection against invasive meningococcal disease. FUNDING Pfizer.


Pediatrics | 2015

13-Valent Pneumococcal Conjugate Vaccine (PCV13) in Preterm Versus Term Infants

Federico Martinón-Torres; Hanna Czajka; Jacek Wysocki; Ewa Majda-Stanislawska; Félix Omeñaca; Enrique Bernaola Iturbe; Daniel Blazquez Gamero; Ana Concheiro-Guisán; Francisco Gimenez-Sanchez; Leszek Szenborn; Peter C. Giardina; Scott D. Patterson; William C. Gruber; Daniel A. Scott; Alejandra Gurtman

OBJECTIVES: This study evaluated the immune response and safety profile of 13-valent pneumococcal conjugate vaccine (PCV13) in preterm infants compared with term infants. METHODS: This Phase IV, open-label, 2-arm, multicenter, parallel-group study enrolled 200 healthy infants (preterm, n = 100; term, n = 100) aged 42 to 98 days. All subjects received PCV13 at ages 2, 3, 4 (infant series), and 12 (toddler dose [TD]) months, together with routine vaccines (diphtheria-tetanus-acellular pertussis, hepatitis B, inactivated poliovirus, and Haemophilus influenzae type b vaccine and meningococcal group C conjugate vaccine). RESULTS: Most subjects achieved an anticapsular immunoglobulin G (IgG) antibody concentration ≥0.35 μg/mL for all serotypes: >85% after the infant series (except preterm infants for serotypes 5, 6A, and 6B) and >97% after TD (except for serotype 3). Preterm infants had overall lower IgG geometric mean concentrations compared with term infants; however, geometric mean fold increases after TD were similar for all serotypes. Opsonophagocytic activity results were consistent with IgG results and titers increased after TD in both groups for all serotypes, including serotype 3. PCV13 was generally well tolerated, with similar safety profiles in all preterm subgroups. CONCLUSIONS: Immune responses were lower in preterm infants than in term infants. However, the majority of subjects in both groups achieved both pneumococcal serotype-specific IgG antibody levels after the infant series that exceeded the World Health Organization–established threshold of protection and functional antibody responses. Responses were uniformly higher after TD, reinforcing the importance of a timely booster dose. PCV13 was well tolerated regardless of gestational age.


World Journal of Pediatrics | 2013

Liver steatosis in Polish children assessed by medicolegal autopsies

Marta Rorat; Tomasz Jurek; Ernest Kuchar; Leszek Szenborn; Wojciech Golema; Agnieszka Halon

BackgroundCases of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are increasing in the pediatric population. Their growing prevalence coincides with the obesity epidemic. Assessment of the incidence requires liver biopsies on a representative population sample, which are hampered by the absence of indications for invasive examination on children without clinical symptoms. The aim of the current study was to assess the incidence of liver steatosis in the population of children up to 18 years old from Lower Silesia.MethodsWe retrospectively reviewed 342 medico-legal autopsy reports from 2000 to 2009. We separated a group of 256 children whose death was caused by trauma. Liver steatosis was diagnosed according to the results of histopathological examinations and typical macroscopic imaging.ResultsIn the 265 children who died from trauma, liver steatosis was reported in 11 (4.2%) children (6 boys) aged between 6 months and 18 years old. Six of the 11 children (54.5%) were found to be overweight. In all 342 children, steatosis was found in 18 (5.3%) children (13 boys), while NASH was diagnosed in 1 (0.3%). Excess body weight was observed in 55.6% (10/18) of children with steatosis.ConclusionsLiver steatosis can occur at any age, even in infancy. Being overweight is a very important risk factor. Gross examination of the liver is insufficient for the diagnosis of steatosis because of its lower sensitivity and specificity. Verification of liver steatosis requires reference histopathological examination.


Mediators of Inflammation | 2015

The Pathogenesis of Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Cervical Adenitis Syndrome: A Review of Current Research

Barbara Kraszewska-Głomba; Agnieszka Matkowska-Kocjan; Leszek Szenborn

Background. PFAPA syndrome is a chronic disease that is characterized by recurrent episodes of high fever, aphthous stomatitis, pharyngitis, and cervical adenitis. Knowledge regarding the etiology of PFAPA is limited. Objectives. To provide up-to-date information considering etiology of PFAPA syndrome, by summarizing what has been explored and established in this area so far. Materials and Methods. PubMed, Web of Science, and Scopus databases were searched for pertinent reports. Eventually 19 articles were selected. The results were classified into categories regarding three areas of interest: familial occurrence, genetic basis, and immunological mechanisms of PFAPA. Results. Recent findings suggest that there is a familial tendency to PFAPA but the level of evidence does not warrant definite conclusions. The absence of a clear monogenic trait indicates a heterogenous, polygenic, or complex inheritance of PFAPA syndrome. As two mutations with a possible functional effect on the inflammasomes (MEFV E148Q and NLRP3 Q703K) have been found in several PFAPA cohorts, the role of inflammasome-related genes in PFAPA pathogenesis cannot be excluded. Immunological mechanisms of PFAPA involve an abnormal, IL-1β dependent innate immune response to an environmental trigger, which leads to Th1-driven inflammation expressed by recruitment of T-cells to the periphery.


Pediatric Infectious Disease Journal | 2013

A randomized, controlled trial to assess the immunogenicity and safety of a heptavalent diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis, hib and meningococcal serogroup C combination vaccine administered at 2, 3, 4 and 12-18 months of age.

Leszek Szenborn; Hanna Czajka; Jerzy Brzostek; Ryszard Konior; Magalie Caubet; Liliana Ulianov; Maarten Leyssen

Background: Combination vaccines offer protection against multiple diseases with fewer injections. This study evaluated the immunogenicity and safety of an investigational diphtheria, tetanus, acellular pertussis, hepatitis B, poliomyelitis, Haemophilus influenzae type b (Hib) and meningococcal serogroup C (MenC) heptavalent combination vaccine (heptavalent vaccine) given as 4 doses at 2, 3, 4 and 12–18 months of age. Methods: In this randomized, open, phase II study (NCT00970307/NCT01171989) conducted in Poland, 421 infants were enrolled to receive the heptavalent vaccine or licensed comparator vaccines. Immunogenicity against study vaccine antigens was measured prior to and 1 month after primary and booster vaccinations. Safety and reactogenicity of the vaccines were also evaluated. Results: The primary noninferiority objectives of the MenC and Hib immune responses induced by the heptavalent vaccine versus comparator vaccines were reached after primary vaccination, but no statistical conclusion could be drawn after booster dose. One month after primary and booster vaccinations, ≥98.4% of the heptavalent vaccine recipients were seroprotected for MenC and Hib. Exploratory analyses indicated that the heptavalent vaccine induced higher postprimary vaccination antibody geometric mean concentrations against Hib, but lower postprimary and postbooster vaccinations geometric mean titers against MenC compared with the relevant comparator vaccines. The reactogenicity profiles of the vaccines were acceptable, although 1 infant vaccinated with the heptavalent vaccine experienced a serious adverse event (thrombocytopenia) considered possibly related to vaccination. Conclusions: The heptavalent vaccine was immunogenic and had a clinically acceptable safety profile when administered to infants and toddlers.


Pediatria polska | 2007

Zalecenia Polskiej Grupy Roboczej ds. Inwazyjnej Choroby Pneumokowej (IChP) u Dzieci dotyczące stosowania siedmiowalentnej skoniugowanej szczepionki przeciwpneumokokowej (PCV7)

Piotr Albrecht; Ewa Bernatowska; Anna Dobrzańska; Paweł Grzesiowski; Waleria Hryniewicz; Ryszard Konior; Marian Patrzałek; Andrzej Radzikowski; Leszek Szenborn; Jacek Wysocki

Czlonkowie grupy roboczej:dr n. med. Piotr Albrechtprof. dr hab. Ewa Bernatowskaprof. dr hab. Anna Dobrzanskadr n. med. Pawel Grzesiowskiprof. dr hab. Waleria Hryniewiczdr n. med. Ryszard Koniordr n. med. Marian Patrzalekprof. dr hab. Andrzej Radzikowskidr n. med. Leszek Szenbornprof. dr hab. Jacek Wysocki

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Ernest Kuchar

Wrocław Medical University

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Jacek Wysocki

Poznan University of Medical Sciences

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Aneta Nitsch-Osuch

Medical University of Warsaw

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Hanna Czajka

Boston Children's Hospital

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Marta Rorat

Wrocław Medical University

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Stan L. Block

University of Louisville

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