2 trial of the safety, tolerability, and immunogenicity of bivalent rLP2086 meningococcal B vaccine in healthy infants

Vaccine 32 (2014) 5206–5211

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A randomized, phase 1/2 trial of the safety, tolerability, and immunogenicity of bivalent rLP2086 meningococcal B vaccine in healthy infants Federico Martinon-Torres a , Francisco Gimenez-Sanchez b , Enrique Bernaola-Iturbe c , Javier Diez-Domingo d,e , Qin Jiang f , John L. Perez f,∗ a

Hospital Clinico Universitario de Santiago, Santiago de Compostela, Spain Complejo Hospitalario Torrecárdenas, Almería, Spain c Hospital Virgen del Camino, Pamplona, Spain d Área de Investigación en Vacunas, Centro Superior de Investigación en Salud Pública (CSISP), Valencia, Spain e Vaccine Research Unit, Instituto de Investigación Sanitaria de Santiago de Compostela, Santiago de Compostela, Spain f Pfizer Vaccine Research, Collegeville, PA, USA b

a r t i c l e

i n f o

Article history: Received 6 February 2014 Received in revised form 3 July 2014 Accepted 15 July 2014 Available online 29 July 2014 Keywords: Neisseria meningitidis serogroup B Factor H-binding protein LP2086 Infants

a b s t r a c t Background: Neisseria meningitidis serogroup B (MnB) is a major cause of invasive meningococcal disease in infants. A conserved, surface-exposed lipoprotein, LP2086 (a factor H-binding protein [fHBP]), is a promising MnB vaccine target. A bivalent, recombinant vaccine targeting the fHBP (rLP2086) of MnB was developed. Methods: This phase 1/2 clinical study was designed to assess the immunogenicity, safety, and tolerability of a 4-dose series of the rLP2086 vaccine at 20-, 60-, 120-, or 200-␮g dose levels in vaccine-naive infants when given with routine childhood vaccines. The study was to consist of two phases: a single-blind sentinel phase and an open-label full enrollment phase. During the sentinel phase, randomization of subjects to the next higher dose was delayed pending a 14-day safety review of dose 1 of the preceding dose cohort. The full enrollment phase was to occur after completion of the sentinel phase. Results: Local reactions were generally mild and adverse events infrequent; however, after only 46 infants were randomized into the study, fever rates were 64% and 90% in subjects receiving one 20- or 60-␮g rLP2086 dose, respectively. Most fevers were <39.0 ◦ C. Only 2 subjects in the 20-␮g group and 1 subject in the 60-␮g group experienced fevers >39.0 ◦ C; no fevers were >40.0 ◦ C. Due to these high fever rates, the study was terminated early. No immunogenicity data were collected. This report discusses the safety and acceptability of rLP2086 in infants after one 20- or 60-␮g dose. Conclusion: Due to the high fever rate experienced in the 20- and 60-␮g groups, rLP2086 in the current formulation may not be acceptable for infants. © 2014 Published by Elsevier Ltd.

1. Introduction Neisseria meningitidis is a major cause of bacterial sepsis and meningitis, often associated with high mortality rates and permanent sequelae in survivors [1]. Rates of invasive disease are highest in infants and adolescents/young adults, with serogroups A, B, C, Y, and W being responsible for most cases [1]. Infection with A, C, Y, and W can be prevented with capsular polysaccharide conjugate vaccines; however, polysaccharide conjugate vaccines

∗ Corresponding author at: Pfizer Vaccine Research, 500 Arcola Road, Collegeville, PA 18926, USA. Tel.: +1 484 865 5424; fax: +1 845 474 4243. E-mail address: john.perez@pfizer.com (J.L. Perez). http://dx.doi.org/10.1016/j.vaccine.2014.07.049 0264-410X/© 2014 Published by Elsevier Ltd.

are not effective against N. meningitidis serogroup B (MnB), which accounts for 33% of meningococcal infections in the United States and the majority in Europe [2–4]. Lipoprotein LP2086, a human factor H-binding protein (fHBP), was identified as a vaccine candidate [5]. The LP2086 gene is highly conserved, with >83% sequence identity within the 2 identified subfamilies, labeled A and B, and is present in all strains included in a database of 1837 invasive MnB isolates [6]. Few strains have been identified to date that do not express fHBP [7,8]. Preclinical studies showed that a bivalent, recombinant LP2086 (rLP2086)-based vaccine containing equal amounts of subfamily A and B proteins could elicit serum bactericidal antibodies capable of killing diverse MnB strains [5,9]. Phase 1 and 2 studies in healthy toddlers, children, adolescents, and adults showed the bivalent rLP2086 vaccine

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to be well tolerated and immunogenic in these patient populations [10–15]. The primary objectives of this study were to assess the immunogenicity, safety, and tolerability of a 4-dose series of bivalent rLP2086 vaccine at 1 of 4 dose levels given with routine childhood vaccines in vaccine-naive infants. The safety data are reported herein.

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included any previous vaccination, previous anaphylactic reaction to any vaccine component, contraindication to vaccination, any clinically significant chronic disease, history of culture-confirmed N. meningitidis or N. gonorrhea infection, receipt of blood products, or impaired immunity. Parents or legal guardians of participants gave written informed consent. 2.3. Vaccination

2. Materials and methods 2.1. Study design This phase 1/2, randomized, multicenter study conducted from January/February 2009 to January 2011 in healthy infants conducted in Spain (ClinicalTrials.gov identifier NCT00798304) planned to enroll 744 subjects. Assuming a 70% seroconversion rate, 160 subjects per group provided ≥95% power to demonstrate ≥50% seroconversion rate for 1 subfamily A strain and 1 subfamily B strain of both vaccine matched and heterologous antigens. The study was to be conducted in 2 stages. Stage 1 was designed to assess the safety and immunogenicity of the MnB rLP2086 vaccine. Stage 1 of this study was single-blind and the sponsor and study staff dispensing and administering the study drug were unblinded. All other personnel, including the principal investigator and parent/legal guardian, were blinded. Stage 2 was designed to evaluate the duration of immunity against MnB for up to 4 years after the end of stage 1. In stage 2, the study was to be open-label and the parent/legal guardian were to be informed of the test article and dose level that the child received. The study was terminated before stage 2. Stage 1 included 2 phases, the sentinel and full enrollment phases. During the sentinel phase, 198 subjects were to be randomly assigned using a computer program to receive 1 of 4 ascending doses (20 ␮g, 60 ␮g, 120 ␮g, and 200 ␮g) of bivalent rLP2086 with routine childhood vaccines or routine vaccines alone at 2, 4, 6, and 12 months of age (Fig. 1). Enrollment of subjects was staggered, starting with the lowest dose cohort (20 ␮g of rLP2086), enrolling 33 subjects in a 2:1 ratio. Randomization of subjects to the 60-␮g dose cohort was delayed pending a 14-day safety review of dose 1. Specifically, the trial was to be stopped by a project-independent safety review committee composed of sponsor employees not involved in this study if ≥4 subjects at each dose level in the sentinel phase had severe erythema or swelling that required medical attention; ≥4 subjects had fever >40 ◦ C occurring ≤7 days after vaccination; or local reactions, systemic events, or other adverse events (AEs) that might jeopardize safety. An ad hoc safety evaluation was to be performed if any of these criteria were met. After review of the 14-day post-dose 1 safety data for the 20␮g dose, sentinel cohort 2 (60 ␮g of rLP2086) opened enrollment for 55 subjects in a ratio of 4:1. The remaining subsequent higher dose groups were to be enrolled similarly after the 14-day post-dose 1 safety data were reviewed. The full enrollment phase was to occur after completion of the sentinel phase; subjects were to be randomized using a computer program in a 2:2:2:1 ratio to receive 60, 120, or 200 ␮g of the rLP2086 vaccine with routine childhood vaccines (up to 546 subjects; 156 subjects per dose level) or routine childhood vaccines only (up to 78 subjects). This study was conducted in accordance with International Conference on Harmonisation Guideline for Good Clinical Practice and the Declaration of Helsinki. The protocol was approved by the institutional review board at each site. 2.2. Study population Infants aged 42–98 days were in good health as determined by medical history and physical examination. Exclusion criteria

Subjects were to be randomly assigned to receive 1 of 4 ascending doses of the bivalent rLP2086 vaccine with routine childhood vaccines or routine vaccines only. The recombinant bivalent rLP2086 vaccine was supplied as a liquid suspension in a prefilled ready-to-use syringe. Each 0.5-mL dose contains 10 ␮g, 30 ␮g, 60 ␮g, or 100 ␮g of purified rLP2086 proteins from each rLP2086 MnB subfamily: strain M98 250771 (variant A05; subfamily A) and strain CDC1573 (variant B01; subfamily B). Inactive ingredients include polysorbate 80 and 0.25 mg of Al3+ as AlPO4 in histidine buffer at pH 6.0 [10]. The DTaP-Hib-HBV + IPV vaccine and Prevenar® (Pfizer Inc, New York, NY, USA) were given concomitantly as routine childhood vaccinations in the contralateral thigh with a 23-gauge, 1-inch needle. One of the several meningococcal C (e.g., Meningitec® , Neis-Vac® , or Menjugate® ) and rotavirus (RotaTeq® or Rotarix® ) vaccines were administered according to the prescribing information at 2 and 4 months of age or 2, 4, and 6 months of age (RotaTeq® only). Subjects were also scheduled to receive the varicella and the measles, mumps, and rubella vaccines; however, no subjects received these vaccinations due to early trial termination. 2.4. Safety and reactogenicity Caregivers recorded solicited reactions 7 days postvaccination in an electronic diary. For erythema and swelling, the largest diameter was measured with a caliper and categorized as absent, mild (0.5–2.0 cm), moderate (2.5–7.0 cm), or severe (>7.0 cm). Tenderness was recorded as not discernible, present, or interfering with limb movement. For subjects who received bivalent rLP2086 vaccine, only reactions at the bivalent rLP2086 vaccine injection site were reported; reactions at the Prevenar® injection site were reported for control subjects. Solicited systemic events included fever (absent [rectal temperature <38.0 ◦ C], mild [38.0 ◦ C to 39.0 ◦ C], moderate [>39.0 ◦ C to 40.0 ◦ C], or severe [>40.0 ◦ C]), irritability, increased/decreased sleep, decreased appetite, and use of antipyretic medication. Other AEs were considered unsolicited and collected throughout the study. AEs were assessed for seriousness and relationship to rLP2086. 2.5. Immunogenicity The study was terminated before the necessary samples were obtained. 2.6. Statistical analysis The safety analysis population included all subjects who received 1 dose of rLP2086. Safety data were summarized using descriptive statistics. 3. Results Tolerability of the rLP2086 vaccine was reasonable after 22 subjects received the 20-␮g dose; however, after 10 subjects received the 60-␮g dose, 1 subject developed aseptic meningitis, triggering a protocol-defined pause and cumulative safety evaluation. Specifically, approximately 10 h after receipt of a 60-␮g dose of rLP2086

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Randomized

Fig. 1. Patient flow diagram. * 1 subject withdrew owing to a urinary tract infection. † 1 subject withdrew owing to aseptic meningitis. ‡ Randomization of subjects to the next higher dose was delayed pending a 14-day safety review of the preceding dose cohort. Safety data were evaluated after completion of each subsequent cohort in the sentinel phase. Enrollment into the full enrollment phase was to occur only after completion of the sentinel phase, which did not occur due to early trial termination in the sentinel phase.

vaccine, Prevenar® , Infanrix hexa® , Meningitec® , and Rotarix® , the subject developed a fever (39.0 ◦ C). A lumbar puncture was performed, and initial results showed 500 cells (95% PMNs), protein 0.5 mg/dl (normal), glucose 60 mg/dl (normal), and red blood cell count of 10 mm3 . The subject was treated with cefotaxime and vancomycin after the lumbar puncture; the fever cleared by the next evening and the child remained afebrile and well. The workup did not identify a causative organism; blood and cerebrospinal fluid (CSF) bacterial and viral cultures were negative; polymerase chain reaction tests of the CSF were also negative. Although the aseptic meningitis was ultimately considered not vaccine related by the treating physician, review of safety data by a project-independent safety committee revealed 80% of vaccine recipients at the 60-␮g dose experienced mild to moderate fever (90% including the case of aseptic meningitis). The sponsor decided to terminate the trial after the vaccine was deemed not acceptable in this population.

lowest in the control group and highest in the 60-␮g group, with the exception of decreased sleep (Table 1). Duration of events was 1.0–3.3 days. Fever ≥38 ◦ C was reported in the majority of rLP2086 vaccine recipients: 14 (64%) in the 20-␮g group and 8 (80%) in the 60-␮g group compared with 4 (29%) in the control group (Fig. 2). In most cases, the temperature was 38.0–39.0 ◦ C; 2 subjects in the 20-␮g group and 1 subject in the 60-␮g group had fever of >39.0–40.0 ◦ C. No fevers were >40.0 ◦ C. The mean duration of fever was 1.0–2.1 days. The subject with aseptic meningitis also reported a fever between >39.0 and 40.0 ◦ C, increasing to 90% the proportion of vaccine recipients reporting fever after a dose of 60 ␮g. The only fever resulting in medical attention was for the subject with aseptic meningitis.

100

3.1. Subject demographics and disposition

60 μg rLP2086 (n=10)

80.0*

80 70.0

70

Subjects, %

At least 1 local reaction was reported for 11 (50%) subjects in the 20-␮g group, 7 (70%) subjects in the 60-␮g group, and 5 (36%) subjects in the control group. The rates of all reactions, except erythema, were lowest in the control group and highest in the 60-␮g group (Table 1). The most common local reaction was tenderness, with a mean duration of 1.3 days, 2.7 days, and 1.0 day in the 20␮g, 60-␮g, and control groups, respectively. Five subjects receiving rLP2086 experienced tenderness that interfered with limb movement. Most subjects experienced ≥1 systemic event. The most common event was irritability, reported for 17 (77%), 9 (90%), and 9 (64%) subjects in the 20-␮g, 60-␮g, and control groups. Rates of the other systemic reactions and anti-pyretic medication use were

20 μg rLP2086 (n=22)

90

Forty-six subjects were randomized: 22 received 20 ␮g rLP2086, 10 received 60 ␮g rLP2086, and 14 received routine childhood vaccines only. Mean age was 65.5 days; 48% were girls; all were white. All subjects received 1 vaccine dose; no postvaccination blood samples were drawn. 3.2. Safety

Control (n=14)

60

63.6 54.5

50 40 30

28.6

28.6

20 9.1

10 0

10.0

0

Mild Moderate (38.0°C–39.0°C) (>39.0°C–40.0°C)

0

0

0

Severe (>40.0°C)

Any

Fig. 2. Fever severity in subjects in the safety population. * Not including the case of aseptic meningitis.

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Table 1 Reactogenicity and adverse events of the safety analysis population. Reaction/event, n (%) Local reactionsa Tenderness (severity) Presentb Interfered with limb movement Indurationc Mild Moderate Erythemac Mild Moderate Systemic eventsa Irritability Decreased appetite Decreased sleep Increased sleep Medication to prevent symptoms Medication to treat symptoms Any systemic event Fevera Absent (<38.0 ◦ C) Mild (38.0 ◦ C–39.0 ◦ C) Moderate (>39.0 ◦ C–40.0 ◦ C) Severe (>40.0 ◦ C) Any fever Adverse events in >5% of subject population Any adverse event Gastroesophageal reflux disease Infections and infestations Urinary tract infection Viral infection Aseptic meningitis Nasopharyngitis Respiratory tract infection Respiratory tract infection viral Asthma Dermatitis Conjunctivitis a b c d

Control n = 14

20 ␮g rLP2086 n = 22

60 ␮g rLP2086 n = 10

2 (14.3) 0

5 (22.7) 1 (4.5)

3 (30.0) 4 (40.0)

2 (14.3) 0

1 (4.5) 3 (13.6)

2 (20.0) 1 (10.0)

4 (28.6) 0

5 (22.7) 1 (4.5)

3 (30.0) 0

9 (64.3) 5 (35.7) 3 (21.4) 4 (28.6) 3 (21.4) 6 (42.9) 12 (85.7)

17 (77.3) 15 (68.2) 12 (54.5) 13 (59.1) 9 (40.9) 11 (50.0) 21 (95.5)

9 (90.0) 7 (70.0) 0 7 (70.0) 6 (60.0) 7 (70.0) 10 (100.0)

10 (71.4) 4 (28.6) 0 0 4 (28.6)

8 (36.4) 12 (54.5) 2 (9.1) 0 14 (63.6)

2 (20.0) 7 (70.0) 1 (10.0) 0 8d (80.0)

3 (21.4) 0 2 (14.3) 0 0 0 0 1 (7.1) 1 (7.1) 1 (7.1) 1 (7.1) 1 (7.1)

7 (31.8) 1 (4.5) 6 (27.3) 2 (9.1) 2 (9.1) 0 0 1 (4.5) 0 0 0 0

2 (20.0) 1 (10.0) 1 (10.0) 0 0 1 (10.0) 1 (10.0) 0 0 0 0 0

Subjects reporting event from electronic diary within 1–7 d. Does not include subjects with tenderness that ‘interfered with arm movement’. Mild, 0.5–2.0 cm; moderate, 2.5–7.0 cm; severe, >7.0 cm. Not including the case of aseptic meningitis.

Nineteen unsolicited AEs were reported among 12 subjects (7 in the 20-␮g group, 2 in the 60-␮g group, and 3 in the control group), most of which were related to infection. Seven serious AEs were reported by 5 subjects, none of which were vaccine related: 4 subjects in the 20-␮g group had bronchitis (2 cases in same subject), urinary tract infection (2 cases), viral infection, and respiratory syncytial virus bronchiolitis; and 1 subject in the 60-␮g group had aseptic meningitis; 2 subjects were withdrawn from the study owing to AEs, neither of which were study related (aseptic meningitis and urinary tract infection; Table 1). 4. Discussion and conclusions Although local reactions were generally mild or moderate and AEs were infrequent, fever rates ranged from 63% to 90% in infants receiving one rLP2086 dose. Most fevers were ≤39.0 ◦ C, with only 2 subjects in the 20-␮g group and 1 subject in the 60-␮g group experiencing fever >39.0 ◦ C; no reported cases were >40.0 ◦ C. Despite the fact that almost 80% of fevers were mild and no cases of severe fever occurred in the 43 trial participants, the high overall fever rate experienced in the 60-␮g group suggests that rLP2086 in the current formulation is not acceptable for infants. Similar to the study presented herein, reactogenicity of the 4CMenB vaccine, Novartis’s fHBP-based MnB vaccine currently licensed in European Union, Canada, and Australia, was also examined in infants. Interestingly, fever rates were similar to those observed in the present study [16,17]. For example, in the most

recent phase 3 study of 4CMenB administered with routine vaccination in infants, 65% (1612/2468) of subjects experienced fevers ≥38.5 ◦ C; fevers ≥40 ◦ C occurred in 1% (29/2468) of subjects [17]. It is possible that the OMV component of 4CMenB contributes at least some of the reactogenicity of this vaccine, as an OMV meningococcal B vaccine (MenNZB) developed to target a specific epidemic strain of MnB in New Zealand also elicited fever rates in infants up to 45% at any dose, 8% of which were ≥39 ◦ C; analgesic use was reported for up to 67% of subjects at any dose [18]; another study of MenNZB in infants in New Zealand showed similar results [19]. However, without a head-to-head trial, direct comparison of the reactogenicity of 4CMenB and the bivalent rLP2086 vaccine in infants is difficult. The question remains as to why bivalent rLP2086 vaccine is not acceptable in infants but is acceptable in other ages, as fevers were rare and generally mild in toddlers (≥18 months of age; 0–31.6%) [15] and adolescents (0–12.5%) [10,11] when administering a 20or 60-␮g dose. Studies in mice suggested that the presence of the lipid tail increases immunogenicity of the vaccine, and thus, the lipidated rLP2086 protein was used in the vaccine [5]. It is plausible that reactogenicity in infants is caused by increased innate immune response to the lipidated protein; however, the same lipidated vaccine is safe and acceptable in toddlers [15] and adolescents [10,11], suggesting an age-related reactogenic effect. Differences in reactogenicity in infants compared with older age groups may be due to age-related differences in innate immune function. Specifically, studies have shown differences in complement protein

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concentrations [20,21] and the phagocytic activity of neutrophils in infants compared with older children [21]. However, although unlikely, the possibility also remains that differences in reactogenicity in infants may be related to a socio-psychological event that resulted in an increased reporting of fevers in this patient group. Overall, a strength of this study lies in the power of its design to quickly identify safety signals while exposing few subjects to the vaccine. Although the study design was sufficient to quickly determine acceptability of rLP2086 in this patient population, important limitations are that early study termination precluded collection of any immunogenicity data and limited safety analysis to only 46 subjects, leaving the possibility that high fever rates were an artifact of small study numbers. Although the rLP2086 vaccine is reactogenic in infants, previous phase 1 and 2 studies suggest that the rLP2086 vaccine is acceptable in other at-risk age groups including toddlers, children, adolescents, and young adults [10,12–15]. Based on the immunogenicity and tolerability profile observed in these studies, the 120-␮g dose was selected for further clinical development. Future studies of bivalent rLP2086 vaccine will aim to find the lower age limit where the vaccine becomes not acceptable. Future studies may also consider alternative administration protocols.

Acknowledgements Editorial/medical writing support was provided by Nicole Gudleski O’Regan, PhD, at Complete Healthcare Communications, Inc., and was funded by Pfizer Inc. FMT’s research activities have been supported by grants from Conselleríade Sanidade/Xunta de Galicia (RHI07/2-intensificación actividad investigadora, PS09749 and 10PXIB918184PR), Instituto Carlos III (Intensificación de la actividad investigadora) and Fondo de Investigación Sanitaria (FIS; PI070069/PI1000540) del plan nacional deI+D+I and ‘fondos FEDER’. Contributors: Other investigators who contributed to this study include A. Carmona (Instituto Hispalense de Pediatria, Seville, Spain), J. Mares (Pediatrics Department De la Costa Brava, Blanes, ˜ (Hospital General de Cataluna, Spain), J.L. Arimany Montana Barcelona, Spain), F. Gimenez Garrido (Hospital Torreccrdenas, Almeria, Spain), A. Concheiro Guisan (Complexo Hospitalario XeralCies de Vigo, Vigo, Spain), J.C. Tejedor (Servicio de Pediatria, Madrid, Spain), J.T. Ramos Amador (Hospital Universitario de Getafe, Madrid, Spain), P. Rojo Conejo (Hospital Universitario 12 de Octubre, Madrid, Spain), L. Sierrasesumaga (Clinica Universitaria de Navarra, Pampola, Spain), P. Infante Marquez (Clinica Virgen del Mar, Almeria, Spain), R. Fernandez-Prieto (Hospital Arquitecto Marcide, Ferrol, Spain), G. Duran (Hospital de Estella, Estella, Spain), J. Aristegui Fernandez (Hospital de Basurto, Bilbao, Spain), C. Calvo (Hospital Severo Ochoa de Leganes, Madrid, Spain), V. Planelles Cantarino (Centro de Salud Paiporta, Valencia, Spain), M. Rivero (H. Universitario de Fuenlabrada, Fuenlabrada, Spain), E. Roman (Hospital Puerta de Hierro-Majadahonda, Madrid, Spain), I. Romero (Hospital de Madrid Torrelodones, Madrid, Spain), J. Ruibal (Hospital Infanta Cristina de Parla, Madrid, Spain), L. Diez (C.S. El Pucol, Valencia, Spain), M. Garces-Sanchez (C.S. Nazaret, Valencia, Spain), M. Peidro (C.S. Trafagalar, Valencia, Spain), L Moreno (Complejo Hospitalario de Navarra. Spain), G. Echarte (Complejo Hospitalario de Navarra. Spain), E. Burillo (Complejo Hospitalario de Navarra. Spain). Conflict of interest statement: QJ and JLP are employees of Pfizer Inc. JDD acts as national coordinator and principal investigator for clinical studies and receives funding from non-commercial funding bodies as well as commercial sponsors (Novartis Vaccines, GlaxoSmithKline, Baxter, Sanofi Pasteur MSD, MedImmune, and Pfizer Vaccines) conducted on behalf of CSISP-FISABIO; JDD also

serves as a board member for GSK and received payment for lectures from SPMSD, Novartis, and Baxter that included support for travel and accommodation for meetings. FGS has received honoraria as consultant/advisor or speaker from Pfizer, GSK, and Sanofi Pasteur MSD in the past. FMT has received research grants and/or honoraria as a consultant/advisor and/or speaker and conducted vaccine trials from GlaxoSmithKline, Sanofi Pasteur MSD, Pfizer Inc/Wyeth, Novartis, Merck, and MedImmune Inc. Funding: This study was sponsored by Pfizer Inc.

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