The Impact of Educational Intervention on Willingness to Enroll in a Clinical Trial of a Gonorrhea Vaccine.

Globally, >80 million new gonorrhea infections occur annually. Here, we assessed barriers to and influences on participation in a gonorrhea clinical trial and the impact of educational intervention. The survey was fielded in the US in March 2022. Higher enrollment of Black/African Americans and younger individuals than represented in the US demographic distribution reflected the higher incidence of gonorrhea in these groups. Behavioral characteristics and baseline attitudes toward vaccination were collected. Participants were probed on their knowledge of and likelihood to enroll in general and gonorrhea vaccine trials. Participants hesitant to enroll in a gonorrhea vaccine trial were given nine bullets of basic facts about the disease and asked again to rank their likelihood to enroll. Overall, 450 individuals completed the survey. Fewer participants were willing (quite/very likely) to join a gonorrhea versus a general vaccine trial (38.2% [172/450] vs. 57.8% [260/450]). The likelihood to enroll in any vaccine trial or a gonorrhea vaccine trial was greater with higher self-declared knowledge (Spearman's ρ = 0.277 [p < 0.001] and 0.316 [p < 0.001], respectively) and baseline openness towards vaccination (p < 0.001 for both). Self-declared awareness of gonorrhea was associated with age (p = 0.001), education (p = 0.031), and ethnicity/race (p = 0.002), with older, more educated, and Black/African Americans having higher awareness. Males (p = 0.001) and those with more sexual partners (p < 0.001) were more likely to enroll in a gonorrhea vaccine trial. Educational intervention had a significant (p < 0.001) impact on hesitancy. Improvement in willingness to enroll in a gonorrhea vaccine trial was greatest in those initially marginally hesitant and lowest in those initially strongly hesitant. Basic educational intervention has the potential to improve recruitment into gonorrhea vaccine trials.

Managing multiplicity in clinical vaccine studies - A case study using a gatekeeping testing strategy.

BACKGROUND: Multiplicity issues are increasingly common in vaccine clinical studies. Common causes include multi-valent combinations/co-administrations requiring separate evaluation of each antigen; numerous efficacy endpoints; requests from regulatory authorities for inclusion of specific powered endpoints into registration studies; interim analyses to support early decision-making. In a Phase III study to evaluate safety and immunogenicity of the 4-component Neisseria meningitidis serogroup B vaccine (4CMenB) when co-administered with 13-valent pneumococcal conjugate vaccine (PCV13) to healthy infants, a total of 49 statistical hypotheses were identified for the primary objectives as requested by the health authority. We designed a sequential testing strategy with visualization using a graphical gatekeeping procedure. METHODS: The 49 immunogenicity objectives related to evaluation of the sufficiency of the 4CMenB immune response; and demonstration of non-inferiority of PCV13 and 4CMenB when co-administered versus administration alone. We used a graphical shortcut display for closed families assuming that the multiple testing procedure is consonant and hypotheses that are rejected by a closed testing procedure are also rejected within the graphical short-cut. The 49 hypotheses were grouped into 10 families and distributed over 4 sequential steps following the clinical and statistical logical relationships agreed with the clinical team. Test decisions within the first 8 families will be made based on p-values with alpha propagation to subsequent families according to the tree structure. RESULTS: This tailored strategy allowed evaluation of all 49 statistical hypotheses individually, and more efficiently. The method avoided a rigid all-or-nothing approach whereby all endpoints fail if one or more null hypotheses cannot be rejected. Clinical input and agreement are critical for designing an efficient and fit-for-purpose strategy. Our experience could encourage more application of such strategies in increasingly complex clinical trials.

Immunogenicity of aIIV3, MF59-adjuvanted seasonal trivalent influenza vaccine, in older adults ≥65 years of age: Meta-analysis of cumulative clinical experience.

OBJECTIVE: Compare the immunogenicity of MF59-adjuvanted trivalent inactivated influenza vaccine (aIIV3; Fluad™) versus conventional trivalent inactivated influenza vaccine (IIV3) in an integrated dataset using a meta-analysis. METHODS: In a meta-analysis, the immunogenicity of aIIV3 in subjects ≥65 years of age was compared with IIV3 immunogenicity using hemagglutination inhibition assay results from 23 phase I through III randomized controlled trials, including 16 first-dose vaccination studies and 7 revaccination studies assessing immunogenicity after second or third annual vaccination. RESULTS: The full analysis set consisted of 11,105 subjects (5869 aIIV3 and 5236 IIV3). In the revaccination studies, 822 individuals received 2 consecutive annual influenza vaccinations (492 aIIV3 and 330 IIV3), and 237 received 3 (150 aIIV3 and 87 IIV3). Overall, across all strains, the meta-analyzed point estimates for seroconversion (SC) and geometric mean titer (GMT) ratio were significantly higher for aIIV3 versus IIV3. The meta-analyzed percent differences in SC with corresponding 95% confidence intervals (CI) for A/H1N1, A/H3N2, and B strain were 9.5% (5.2-13.9), 10.5% (6.6-14.5), and 12.7% (8.6-16.8), respectively. The meta-analyzed GMT ratios with corresponding 95% CI for A/H1N1, A/H3N2, and B strain were 1.15 (1.01-1.31), 1.30 (1.18-1.44), 1.23 (1.15-1.31). Antibody responses against heterologous influenza strains were also significantly higher with aIIV3. Revaccination studies showed continued robust immune response to aIIV3 with repeated vaccination. CONCLUSIONS: aIIV3 elicited a statistically significantly greater immune response compared to conventional IIV3 in older adults, increasing the breadth and duration of the immune response.

Cumulative clinical experience with MF59-adjuvanted trivalent seasonal influenza vaccine in young children and adults 65 years of age and older.

OBJECTIVE: To assess the long-term safety of MF59-adjuvanted trivalent influenza vaccine (aIIV3; Fluad™) in adults ≥65 years of age. METHODS: Data from 36 primary vaccination and 7 re-vaccination Phase I through III trials were analyzed; 7532 subjects received aIIV3 and 5198 subjects a nonadjuvanted trivalent inactivated influenza vaccine (IIV3). These trials were evaluated in 2 data poolings: first-dose randomized controlled trials (FD-RCT) and revaccination trials. Spontaneously reported adverse events (AEs) from post-marketing surveillance were also analyzed. RESULTS: The percentages of subjects reporting AEs following vaccination were similar between aIIV3 and IIV3: 24.8% for aIIV3 vs 26.7% for IIV3 (relative risk [RR] 0.94; 95% confidence interval [CI] 0.87-1.01). The percentage of subjects with serious AEs was 6.7% for aIIV3 vs 7.0% for IIV3 (RR 0.95; 95% CI 0.82-1.09). Percentages of subjects with AEs leading to withdrawal, hospitalizations, adverse events of special interest (AESIs), and deaths between vaccination groups were similar. There was no signal of disproportionality for AESIs associated with aIIV3 compared to IIV3 in the post-marketing database. CONCLUSIONS: This integrated safety analysis demonstrates an acceptable safety profile for aIIV3 in adults ≥65 years of age.

Influence of Statins on Influenza Vaccine Response in Elderly Individuals.

Influenza vaccination strategies have targeted elderly individuals because they are at high risk of disease complications and mortality. Statins are a class of drugs used to treat hypercholesterolemia and are frequently used in the elderly population to reduce the risk of cardiovascular disease. However, statins are also known to have immunomodulatory effects that could impact influenza vaccine response. In a post hoc analysis, we performed a cross-sectional observational study nested within a comparative immunogenicity clinical trial of adjuvanted versus unadjuvanted influenza vaccine in elderly persons to evaluate the influence of statin therapy on the immune response to vaccination. Overall, data on >5000 trial participants were available for analysis. Comparison of hemagglutination-inhibiting geometric mean titers to influenza A(H1N1), A(H3N2), and B strains revealed that titers were 38% (95% confidence interval [CI], 27%-50%), 67% (95% CI, 54%-80%), and 38% (95% CI, 28%-29%) lower, respectively, in subjects receiving chronic statin therapy, compared with those not receiving chronic statin therapy. This apparent immunosuppressive effect of statins on the vaccine immune response was most dramatic in individuals receiving synthetic statins. These effects were seen in both the adjuvanted and unadjuvanted vaccine groups in the clinical trial. These results, if confirmed, could have implications both for future clinical trials design, as well as for vaccine use recommendations for elderly individuals.

Comparison of the safety and immunogenicity of an MF59®-adjuvanted with a non-adjuvanted seasonal influenza vaccine in elderly subjects.

AIM: Adjuvanted influenza vaccines can overcome the poor antibody response of conventional non-adjuvanted vaccines in the elderly. We evaluated the immunogenicity, safety and clinical effectiveness of an MF59(®)-adjuvanted trivalent influenza vaccine (aTIV) compared with a non-adjuvanted vaccine (TIV) in subjects ≥65 years old, with or without co-morbidities. METHODS: In 2010-2011, subjects (N=7082) were randomized to receive one dose of aTIV or TIV. Co-primary objectives were to assess lot-to-lot consistency of aTIV, non-inferiority, superiority and immunogenicity 22 days after vaccination. Clinical effectiveness, reactogenicity and serious adverse events were monitored up to Day 366. RESULTS: The immunological equivalence of three lots of aTIV was demonstrated. aTIV was not only non-inferior to TIV but also elicited significantly higher antibody responses at Day 22 than TIV against all homologous and heterologous strains, even in subjects with co-morbidities. Superiority was not established. Reactogenicity was higher in the aTIV group, but reactions were mild to moderate and transient. CONCLUSIONS: aTIV elicited a significantly higher antibody response than TIV, especially against A/H3N2 strains, although superiority by pre-defined criteria was not formally met. The study demonstrates potential immunological benefits of MF59-adjuvanted influenza vaccines for the elderly. This trial was registered with www.clinicaltrials.gov (NCT01162122).

A dose-ranging study in older adults to compare the safety and immunogenicity profiles of MF59®-adjuvanted and non-adjuvanted seasonal influenza vaccines following intradermal and intramuscular administration.

UNLABELLED: Strategies to optimize responses to seasonal influenza vaccination in older adults include the use of adjuvants, higher antigen doses, and intradermal delivery. In this study adults aged ≥65 years (n = 450) received a single dose of 1 of 2 non-adjuvanted trivalent influenza vaccine (TIV) formulations administered intradermally (ID), both containing 6 µg of A/H1N1 and B, differing in A/H3N2 content (6 µg or 12 µg), or a single dose of 1 of 8 TIV formulations administered intramuscularly (IM) all containing 15 µg of A/H1N1 and B, differing in A/H3N2 hemagglutinin (HA) content (15 µg or 30 µg) and/or in MF59(®) adjuvant content (0%, 25%, 50%, or 100% of the standard dose). This paper focuses on the comparisons of low-dose non-adjuvanted ID, full-dose non-adjuvanted IM and full-dose MF59-adjuvanted IM formulations (n = 270). At day 22 post-vaccination, at least one European licensure immunogenicity criterion was met by all groups against all 3 strains; however, all three criteria were met against all 3 vaccine strains by the low-dose non-adjuvanted ID and the full-dose MF59-adjuvanted IM groups only. The full-dose MF59-adjuvanted IM group elicited significantly higher immune response vs. the low-dose non-adjuvanted ID formulations for most comparisons. The full-dose MF59 adjuvanted IM groups were associated with increased pain at the site of injection (P<0.01) compared to the ID groups, and the low-dose non-adjuvanted ID groups were associated with increased erythema, induration, and swelling at the injection site (P<0.0001) and unsolicited AEs compared with the IM groups. There were no differences between IM and ID groups in the frequencies of subjects experiencing solicited systemic reactions. Overall, while MF59 adjuvantation increased pain at the site of injection, and intradermal delivery increased unsolicited adverse events, erythema, induration, and swelling at the injection site, both strategies of vaccination strongly enhanced the immunogenicity of seasonal influenza vaccine in older adults compared with conventional non-adjuvanted intramuscular delivery. TRIAL REGISTRATION: http://www.clinicaltrials.gov: NCT00848848.

A phase II study of an investigational tetravalent influenza vaccine formulation combining MF59®: adjuvanted, pre-pandemic, A/H5N1 vaccine and trivalent seasonal influenza vaccine in healthy adults.

An investigational tetravalent vaccine combining pre-pandemic, MF59®-adjuvanted A/H5N1 vaccine with non-adjuvanted, trivalent, seasonal influenza vaccine has been developed, which has the potential to be used for pre-pandemic priming and to improve levels of compliance and coverage. It is important to determine whether the safety and immunogenicity of the combination vaccine is equivalent to that of the two separate vaccines when administered concomitantly. Healthy adults (n=601) were randomly assigned to three vaccination groups to receive either: (1) tetravalent vaccine and placebo concomitantly (in separate arms) on Day 1, followed by A/H5N1 vaccine on Day 22; (2) A/H5N1 vaccine and placebo concomitantly on Day 1, followed by tetravalent vaccine on Day 22; or (3) A/H5N1 and seasonal vaccines concomitantly on Day 1, followed by A/H5N1 vaccine on Day 22. Antibody responses were measured using single radial hemolysis (SRH), haemagglutination inhibition (HI), and microneutralization (MN) assays on Days 1, 22, and 43. Solicited adverse reactions were recorded for seven days after vaccination. Spontaneous adverse events were recorded throughout the study. The tetravalent vaccine elicited antibody titers equivalent to those for separate A/H5N1 and seasonal vaccines, and sufficient to meet the European licensure criteria against A/H5N1 and all three seasonal strains. Local and systemic reactions were mainly mild to moderate. No vaccine-related serious adverse events occurred. These findings demonstrate that MF59-adjuvanted A/H5N1 and seasonal influenza vaccines had an acceptable safety profile and could be effectively administered as a tetravalent formulation, supporting the possibility of integrating pre-pandemic priming into seasonal influenza vaccination programs.

Impact of preexisting memory to seasonal A/H1N1 influenza virus on the immune response following vaccination against avian A/H5N1 virus.

Cross-protection against divergent strains of influenza virus is an objective of various vaccination approaches. B cells cross-neutralizing several influenza A heterosubtypes have been isolated from cultured human memory B cells (MBCs) and plasmablasts early after influenza vaccination or infection. However, a systematic assessment of the frequency of MBCs and plasmablasts in the blood of healthy individuals is lacking. Here, we show that under resting conditions about 45% of human adults never vaccinated nor exposed to avian A/H5N1 influenza have detectable circulating MBCs cross-reacting with H5N1. This proportion rises to 63.3% among subjects with a large pool of MBCs specific for seasonal H1N1 (i.e. frequency ≥1% of total IgG MBCs). Moreover, subjects with high baseline frequencies of H1N1-specific MBCs had an expansion of H5N1-specific MBCs producing H5-neutralizing antibodies already after the first dose of an MF59-adjuvanted H5N1 vaccine. These results suggest that H1N1-specific MBCs contain a subset of cells cross-reacting to H5. We propose that a proportion of human adults have a pool of H5/H1 cross-reactive MBCs that contribute to the rapid rise of the antibody response to divergent influenza strains. This may have implications on vaccination strategies aimed at counteracting future influenza pandemics.

Superior immunogenicity of seasonal influenza vaccines containing full dose of MF59 (®) adjuvant: results from a dose-finding clinical trial in older adults.

BACKGROUND: MF59-adjuvanted influenza vaccines have superior immunogenicity in older adults compared with non-adjuvanted vaccines. We assessed whether changing formulation (i.e., increasing H3N2 antigen or decreasing the quantity of adjuvant) of the licensed, MF59-adjuvanted trivalent influenza subunit vaccine Fluad (®) (Novartis Vaccines and Diagnostics) improves the risk-benefit profile in vaccinees aged ≥ 65 years. RESULTS: A significant dose-response relationship was observed between antibody levels and MF59 dose; full dose formulations elicited the strongest immune responses, meeting immunogenicity licensure criteria by Day 8. Doubling H3N2 antigen content did not increase the response to this antigen. Increased frequency of circulating CD4+ T-cells specific for vaccine antigens were detected by Day 8; magnitude and functional profile of the CD4+ T-cell response was comparable across the different vaccination groups. Mild to moderate solicited local reactions were more common with vaccines formulated with higher doses of MF59 (®) , but there were no MF59- or antigen dose-related increase in the frequency of solicited systemic reactions or unsolicited adverse events and serious adverse events. METHODS: We report on 357 subjects who received one of eight intramuscular vaccine formulations. Hemagglutination-inhibiting antibodies were assayed on Days 1, 8 and 22; magnitude and functional profile of CD4+ T-cell responses to vaccine antigens were assessed in subsets. Solicited adverse reactions were reported via diary cards for seven days after vaccination and spontaneous adverse events were monitored throughout the study. CONCLUSION: This study confirms that the current formulation is the optimal one for MF59-adjuvanted influenza vaccine for use in older adults.

Hemagglutination inhibition antibody titers as a correlate of protection for inactivated influenza vaccines in children.

INTRODUCTION: The hemagglutination inhibition (HI) titer of 1:40, which has been recognized as an immunologic correlate corresponding to a 50% reduction in the risk of contracting influenza, is based on studies in adults. Neither seasonal nor challenge-based correlates have been evaluated in children. METHODS: A total of 4707 influenza vaccine-naive healthy children 6 to 72 months old were randomized in a ratio of 2:2:1 to receive 2 doses of MF-59-adjuvanted influenza vaccine (Novartis Vaccines), trivalent inactivated influenza vaccine subunit (trivalent inactivated influenza vaccine control, GSK), or a saline placebo during the 2007 to 2008 and 2008 to 2009 influenza seasons. The second dose was given 30 days after dose 1. Clinical influenza-like illnesses cases identified by active surveillance were confirmed by reverse transcription polymerase chain reaction testing for influenza. Vaccine immunogenicity 50 days after dose 1 was evaluated in a subset of 777 children. RESULTS: Immunogenicity and efficacy results for H3N2 were evaluated against the Prentice criteria, which confirmed that the immunogenicity results warranted estimation of an immunologic correlate. We then used the Dunning model fitting the H3N2 antibody titers at day 50 and the influenza cases observed in the immunogenicity subset to estimate a correlate of protection. This analysis revealed that a cutoff HI titer of 1:110 was associated with the conventional 50% clinical protection rate against infection during the entire season, and titers of 1:215, 1:330, and 1:629 predicated protection rates of 70%, 80%, and 90%, respectively. The conventional adult HI titer of 1:40 was only associated with 22% protection. CONCLUSIONS: The use of the 1:40 HI adult correlate of protection is not appropriate when evaluating influenza vaccines in children. Although a cutoff of 1:110 may be used to predict the conventional 50% clinical protection rate, a titer of 1:330 would predict an 80% protective level, which would seem to be more desirable from a public health perspective.

Trivalent and quadrivalent MF59(®)-adjuvanted influenza vaccine in young children: a dose- and schedule-finding study.

Young children are at increased risk for influenza infections and related complications. The protection offered to children by conventional trivalent inactivated influenza vaccines (TIV) is suboptimal, due to poor immunogenicity and a higher exposure to infection and complications in this age group, particularly from influenza B strains. In this dose-ranging, factorial design trial, we report the safety and immunogenicity of different combinations of adjuvanted (ATIV) and non-adjuvanted trivalent (TIV) and quadrivalent (QIV) influenza vaccines in 480 healthy children 6 to <36 months of age. The results show that the second B strain added to TIV was immunogenic and did not affect immunogenicity of the other strains. The addition of the MF59(®) adjuvant promoted robust immune responses with notable elevations in antibodies observed even after one dose. A dose-response relationship was observed between the antibody response and MF59 adjuvant. No patterns in safety and tolerability emerged with different adjuvant and antigen doses nor with the addition of a second B strain. MF59-adjuvanted QIV offers potential advantages to young children.

Explorations of clinical trials and pharmacovigilance databases of MF59®-adjuvanted influenza vaccines for associated cases of narcolepsy.

BACKGROUND: A potential association between the new onset of narcolepsy accompanied by cataplexy - a putative autoimmune disorder, and vaccination with an AS03-adjuvanted A(H1N1) pandemic influenza vaccine is under investigation. We sought cases of narcolepsy from the pharmacovigilance database of a pandemic vaccine adjuvanted with another emulsion adjuvant, MF59(®), and a pooled clinical trials database of MF59-adjuvanted and non-adjuvanted influenza vaccine recipients. METHODS: Using 6 narrowly restrictive and 24 broad sleep disturbance-related MedDRA preferred search terms (PT), we analysed spontaneous adverse events (AEs) reports received through July 31, 2010 and adjudicated suspected cases with onset 1 week-3 months after vaccination, against standardized clinical criteria defining narcolepsy. A pooled clinical trials database of 115 trials comprising 79,004 subjects receiving various MF59-adjuvanted and non-adjuvanted influenza vaccines in controlled and uncontrolled trials was analysed for cases with a narrow PT that had onset 1 week after vaccination. RESULTS: Five thousand three hundred and five spontaneous AE reports were received from an estimated 23.26 million MF59-adjuvanted pandemic vaccine doses that had been administered. No case meeting the clinical definition of narcolepsy was discovered. In the pooled database of controlled clinical trials, no cases were discovered using the narrow PT, and rates and adjusted odds ratio for broad search terms for all temporal windows showed no significant difference between subjects receiving MF59-adjuvanted or non-adjuvanted vaccine. CONCLUSIONS: No case of narcolepsy and no evidence of an increased risk of sleep-related AEs were discovered in recipients of MF59-adjuvanted A(H1N1) pandemic and other MF59-adjuvanted influenza vaccine.

Safety of MF59-adjuvanted versus non-adjuvanted influenza vaccines in children and adolescents: an integrated analysis.

We reviewed the safety of MF59-adjuvanted versus non-adjuvanted influenza vaccines in children and adolescents (aged 6 months-18 years) in an integrated analysis of all pediatric trials evaluating MF59-containing influenza vaccines completed to date (5 trials). In the MF59-adjuvanted group (n=1181) versus the non-adjuvanted group (n=545) there was no increase in the incidence of unsolicited adverse events and serious adverse events. As expected, solicited local or systemic reactions occurred more frequently in MF59-adjuvanted subjects; however, a majority of reactions were mild and transient. These data support the safety of MF59-adjuvanted influenza vaccines in the pediatric population.

MF59-adjuvanted versus non-adjuvanted influenza vaccines: integrated analysis from a large safety database.

BACKGROUND: Adding adjuvants such as MF59((R)) to influenza vaccines can enhance the immune response. This analysis evaluated the safety profile of MF59-adjuvanted [(+)MF59] compared with non-adjuvanted [(-)MF59] vaccines in a large clinical database. METHODS: Safety data were pooled from 64 clinical trials involving (+)MF59 seasonal and pandemic influenza vaccines. Safety outcomes were analysed in the overall population and in subjects aged > or =65 years, in all clinical trials and in controlled trials only. FINDINGS: Data from 20,447 (+)MF59 and 7526 (-)MF59 subjects were analysed. Overall, (+)MF59 subjects had lower risks than (-)MF59 subjects of experiencing any unsolicited adverse event (AE) (26.8% vs 39.2%; adjusted risk ratio [ARR] 0.65; 95% CI 0.60-0.70), cardiovascular AEs (1.9% vs 5.6%; ARR 0.44; 95% CI 0.35-0.55), new onset chronic diseases (1.3% vs 1.9%; ARR 0.71; 95% CI 0.57-0.87) and death (0.8% vs 1.2%; ARR 0.67; 95% CI 0.51-0.87). Few AEs of potential autoimmune origin were reported: 0.71 and 0.67 per 1000 with (+)MF59 and (-)MF59, respectively. As expected, (+)MF59 subjects had a higher risk of solicited local or systemic reactions within 3 days of vaccination (58.5% vs 46.9%, weighted RR 1.34; 95% CI 1.28-1.40). Safety outcomes were consistent between total and elderly populations, and between all trials and controlled trials, although statistical significance was lost for some of the outcomes in the subgroups. INTERPRETATION: This large-scale analysis supports the good safety profile of (+)MF59 seasonal and pandemic influenza vaccines and suggests a clinical benefit over (-)MF59 influenza vaccines.

Evaluation of operational chronic infection endpoints for HCV vaccine trials.

Hepatitis C virus (HCV) is a leading cause of chronic liver disease. The natural history of HCV infection is heterogeneous, and a person infected with HCV can clear the virus or progress to a chronic infection. The chronic infection can remain asymptomatic for decades before the development of liver cirrhosis and/or carcinoma. Currently, there are no assays that can differentiate a transient infection (an acute infection that would clear) from a chronic infection, and serial HCV RNA testing is used to operationally define chronic hepatitis C (e.g. detectable HCV over 6 months). Therefore, HCV vaccine trial planning can benefit from the assessment of the endpoint candidates that are aimed at the chronic infection. Operationally defined endpoints based on the virological tests at study visits have been previously studied in the context of human papillomavirus (HPV) vaccine trials. However, HCV natural history is different from HPV, requiring separate considerations. In this work, several definitions of chronic infection that are based on the periodically observed HCV RNA statuses are evaluated, using a multi-state, time-homogeneous Markov model for transient and chronic infections under various infection settings. Our results show some inflation in the type I error in the log-rank test on the vaccine efficacy against chronic infections in the presence of vaccine efficacy related to transient infections. A type I error up to almost four times the planned rate of 5% is observed in one setting. Overall, simple operational endpoints yield higher power than more complex endpoints, but the simplest endpoint is most affected by the type I error inflation and misclassification error due to the assay imperfection.

Tick-born encephalitis (TBE) vaccination in children: advantage of the rapid immunization schedule (i.e., days 0, 7, 21).

Tick-borne encephalitis (TBE) is an important, vaccine-preventable arthropod-borne disease, causing severe illness in children too. In order to evaluate the immune response to different licensed primary immunization schedules, a total of 294 children aged 1 to 11 years of age were enrolled in a randomized, controlled, multi-center trial. The subjects were vaccinated with the pediatric formulation of a TBE vaccine (Encepur children) according to the conventional schedule (Group C; N = 73, vaccination on days 0, 28 and 300), the modified conventional schedule (Group M; N = 139, vaccination on days 0, 21 and 300), or the rapid schedule (Group R; N = 82, vaccination on Days 0, 7 and 21). Antibody titers as measured by neutralization-test (NT) and ELISA were determined on Days 0, 42, 180, 300, and 321. The demographic data of the study groups were similar. Most subjects (97%-100%) reached an NT titer of at least 1:10 on Day 42. On Day 42, the highest NT geometric mean titers (GMTs) were reached in Group C. In Group C and Group M, titers declined up to Day 300. Until Day 300, the highest NT-GMTs were maintained in Group R, notably without a decline compared to Day 42. Group M reached titers similar to Group R on Day 42, but these titers declined by 50% up to Day 180. Similar to the NT, on Day 42 highest geometric mean concentrations (GMCs) as measured by ELISA across all groups were reached in Group C. In all groups, titers declined until Day 300. On Day 300, GMC ELISA of Group R was higher compared to Group C and Group M. To conclude, the rapid immunization schedule in children not only provides fast protection but also leads to stable titers as measured by NT for at least 300 days after vaccination.

Overcoming the need for a cold chain with conjugated meningococcal Group C vaccine: A controlled, randomized, double-blind study in toddlers on the safety and immunogenicity of Menjugate, stored at room temperature for 6 months.

Millions of vaccine doses are wasted each year due to a lapse in recommended storage conditions. Maintaining the cold chain for vaccines is both expensive and difficult, especially in developing countries. The present study investigated the safety and immunogenicity of a single dose of the conjugated meningococcal Group C vaccine, Menjugate, stored for 6 months at room temperature (25+/-2 degrees C, N=250) or at 2-8 degrees C (N=250) when administered to 12-23 months toddlers. In the two respective groups, 87 and 88% of toddlers reached bactericidal antibodies titers of at least 1:8. The immunogenicity of Menjugate stored at room temperature was not inferior to that stored at 2-8 degrees C. The safety profile and immunogenicity of the vaccine was not influenced by the storage condition.

Replacement IgG therapy and self-therapy at home improve the health-related quality of life in patients with primary antibody deficiencies.

PURPOSE OF REVIEW: This article describes the health-related quality of life and health of patients suffering from primary antibody deficiencies before and after the initiation of lifelong IgG replacement therapy, and before and after the introduction of home-therapy regime programmes. The importance of including patient-reported or parent-reported outcomes in evaluations of treatment and care of this group of patients is also discussed. RECENT FINDINGS: Recently diagnosed adults suffering from primary antibody deficiencies and not yet on IgG therapy report poor health and poor health-related quality of life as compared with healthy individuals. Weekly subcutaneous IgG infusions (100 mg/kg) significantly improve health and normalize health-related quality of life. IgG self-infusions at home further improve the self-reported health and health-related quality of life of both adults and children. Being able to self-infuse at home instead of visiting the hospital two to four times per month has been shown to increase the treatment satisfaction of both adult patients and their families, and to result in increased flexibility, independence and sense of self-control. SUMMARY: Adequate IgG replacement therapy means a dramatically improved life situation. Home-therapy programmes should be encouraged, as self-infusions at home further improve health-related quality of life and self-perceived health.

Safety and efficacy of self-administered subcutaneous immunoglobulin in patients with primary immunodeficiency diseases.

Intravenous immunoglobulin (IVIg) infusions at 3-4 week intervals are currently standard therapy in the United States for patients with primary immune deficiency diseases (PIDD). To evaluate alternative modes of immunoglobulin administration we have designed an open-label study to investigate the efficacy and safety of a subcutaneously administered immunoglobulin preparation (16% IgG) in patients with PIDD. After their final IVIg infusion, 65 patients entered a 3-month, wash-in/wash-out phase, designed to bring patients to steady-state with subcutaneously administered immunoglobulin. This was followed by 12 months of weekly SCIg infusions, at a dose determined in a pharmacokinetic substudy to provide noninferior intravascular exposure. This resulted in a mean weekly dose of 158 mg/kg, calculated to equal 137% of the previous intravenous dose. Two patients (4%) each reported 1 serious bacterial infection (pneumonia), an annual rate of 0.04 per patient-year. There were 4.43 infections of any type per patient-year. Mean trough serum IgG levels increased from 786 to 1040 mg/dL during the study, a mean increase of 39%. The most frequent treatment-related adverse event was infusion-site reaction, reported by 91% of patients; this was predominantly mild or moderate, and the incidence decreased over time. No treatment-related serious adverse events were reported. We conclude that subcutaneous administration of 16% SCIg is a safe and effective alternative to IVIg for replacement therapy of PIDD.