Incidence of Respiratory Syncytial Virus-Associated Lower Respiratory Tract Illness in Infants in Low- and Middle-Income Regions During the Coronavirus Disease 2019 Pandemic.

Background: Incidence data of respiratory syncytial virus-associated lower respiratory tract illness (RSV-LRTI) are sparse in low- and middle-income countries (LMICs). We estimated RSV-LRTI incidence rates (IRs) in infants in LMICs using World Health Organization case definitions. Methods: This prospective cohort study, conducted in 10 LMICs from May 2019 to October 2021 (largely overlapping with the coronavirus disease 2019 [COVID-19] pandemic), followed infants born to women with low-risk pregnancies for 1 year from birth using active and passive surveillance to detect potential LRTIs, and quantitative reverse-transcription polymerase chain reaction on nasal swabs to detect RSV. Results: Among 2094 infants, 32 (1.5%) experienced an RSV-LRTI (8 during their first 6 months of life, 24 thereafter). Seventeen (0.8%) infants had severe RSV-LRTI and 168 (8.0%) had all-cause LRTI. IRs (95% confidence intervals [CIs]) of first RSV-LRTI episode were 1.0 (.3-2.3), 0.8 (.3-1.5), and 1.6 (1.1-2.2) per 100 person-years for infants aged 0-2, 0-5, and 0-11 months, respectively. IRs (95% CIs) of the first all-cause LRTI episode were 10.7 (8.1-14.0), 11.7 (9.6-14.0), and 8.7 (7.5-10.2) per 100 person-years, respectively. IRs varied by country (RSV-LRTI: 0.0-8.3, all-cause LRTI: 0.0-49.6 per 100 person-years for 0- to 11-month-olds). Conclusions: RSV-LRTI IRs in infants in this study were relatively low, likely due to reduced viral circulation caused by COVID-19-related nonpharmaceutical interventions. Clinical Trials Registration: NCT03614676.

Adverse infant outcomes following low-risk pregnancies in England: a retrospective cohort study.

BACKGROUND: There are limited data describing adverse infant outcomes in infants born to women with a low risk of complications during pregnancy, such as those who may be enrolled in maternal immunization trials. This retrospective study estimated incidence proportions of infant outcomes in different cohorts of liveborn infants in England between 2005 and 2017. METHODS: The incidence proportions of 10 infant outcomes were calculated for liveborn infants from pregnancies represented in the Clinical Practice Research Datalink (CPRD) Mother-Baby Link (MBL) and linkage to Hospital Episode Statistics (HES). Three infant cohorts were designed: (1) the all pregnancies infants cohort (N = 185,119), (2) the all pregnancies with a gestational age (GA) ≥ 24 weeks infants cohort (N = 183,869), and (3) the low-risk pregnancies infants cohort (LR infants cohort, N = 121,871), which included pregnancies with a GA ≥ 24 weeks and no diagnosis of predefined high-risk medical conditions until 24 weeks GA. RESULTS: The most common adverse infant outcome in the three infant cohorts was macrosomia (e.g., 1,085.9/10,000 live births in the LR infants cohort), followed by minor congenital anomalies (e.g., 800.6/10,000 in the LR infants cohort), very low/low birth weight (e.g., 400.6/10,000 in the LR infants cohort), and major congenital anomalies (e.g., 270.4/10,000 in the LR infants cohort). The incidence proportions for early-onset sepsis, very low/low birth weight, and minor and major congenital anomalies were lower in the LR infants than in the other cohorts (non-overlapping confidence intervals [CIs]). The incidence proportions of neonatal death, infant death, late-onset sepsis, macrosomia, small for GA, and large for GA were similar between cohorts (overlapping CIs). CONCLUSIONS: This study generated background rates of adverse infant outcomes from liveborn infants of all and low-risk pregnancies represented in the CPRD Pregnancy Register MBL and linkage to HES. The results indicate lower incidence proportions of several adverse infant outcomes in infants from low-risk pregnancies compared to all pregnancies, illustrating the importance of considering maternal risk factors. These background rates may facilitate the interpretation of safety data from maternal immunization trials and of pharmacovigilance data from maternal vaccines. They may also be of interest for other interventions studied in pregnant women.

Demographic diversity of US-based participants in GSK-sponsored interventional clinical trials.

BACKGROUND: Demographic diversity among clinical trials is required for representing the real-world populations intended for treatment and disease prevention. Moreover, genetic and environmental differences between ethnic and racial groups necessitate appropriately powered trials for relevant subgroups. We investigate the racial and ethnic demographic diversity of US-based participants in GSK-sponsored interventional trials. We also assess the evaluation of demographic diversity against US Census and epidemiologic data. METHODS: GSK-sponsored interventional phase I-IV clinical trials conducted from 2002 to 2019 across three areas were analyzed: pharmaceutical (includes therapeutic medicines except for vaccines and human immunodeficiency virus (HIV)), vaccine (includes prophylactic and therapeutic vaccines), and ViiV (includes HIV therapies). A total of 1005 global trials encompassing 460,707 global participants were identified, of which 495 had US-based sites with a total of 108,261 (23.5% of global) US participants (pharmaceutical, n = 357 trials; vaccine, n = 45 trials; and ViiV, n = 93 trials). We evaluated how GSK US-based trial recruitment compares with US Census (in line with previously published studies from other groups) and with epidemiologic data. RESULTS: GSK participant data for race and ethnicity combined across areas were generally similar to US Census levels (e.g. GSK versus census: White, 76.5% versus 76.3%; Black or African American, 15.1% versus 13.4%; Asian, 1.8% versus 5.9%; Hispanic or Latino, 14.0% versus 18.5%; Non-Hispanic White, 63.5% versus 60.1%). However, this was not the case for the individual pharmaceutical, vaccine, and ViiV data sets; least represented groups were Asian individuals for pharmaceutical and ViiV trials and American Indian or Alaskan Native individuals for vaccine trials (6.2%, 11.8%, and 11.1% of trials met/exceeded census level representation, respectively). The percentage of trials reaching/exceeding census levels also varied per trial phase for race and ethnicity. Furthermore, disparities in the percentage of trials reaching/exceeding census levels versus epidemiology-based prevalence levels have revealed opportunities to improve industry success metrics; in HIV trials, the proportion of Black or African American individuals (35.1%) exceeded census (13.4%) but not epidemiologic levels (55.3%). CONCLUSION: Further work is required to achieve demographic diversity across clinical trials. We conclude that US Census data are an inappropriate universal benchmark. A shift to epidemiology benchmarking will enable the consideration of global participants into US analyses for highly intrinsic (i.e. influenced by ancestry) diseases and more firm requirements for US-based participants into US analyses for extrinsic (i.e. influenced by location or culture) diseases. Benchmarking in line with epidemiologic data will allow us to set better trial enrollment goals, with the aim of conducting more demographically balanced, diverse, and representative clinical trials and enabling a better understanding of drug safety and efficacy per demographic group.

Safety and Immunogenicity of an Investigational Respiratory Syncytial Virus Vaccine (RSVPreF3) in Mothers and Their Infants: A Phase 2 Randomized Trial.

BACKGROUND: In a phase 1/2 study, a maternal respiratory syncytial virus vaccine candidate (RSVPreF3) demonstrated an acceptable safety profile and efficiently increased RSV-specific humoral immune responses in non-pregnant women. METHODS: In this phase 2 observer-blind, placebo-controlled, randomized clinical trial (NCT04126213), the safety of RSVPreF3 (60 or 120 µg), administered during late second or third trimester, was evaluated in 213 18- to 40-year-old healthy pregnant women through 6 months postdelivery and their offspring through infancy; immunogenicity was evaluated through day 43 postdelivery and day 181 postbirth, respectively. RESULTS: RSVPreF3 was well tolerated. No pregnancy-related or neonatal adverse events of special interest were considered vaccine/placebo related. In the 60 and 120 µg RSVPreF3 groups: (1) neutralizing antibody (nAb) titers in mothers increased 12.7- and 14.9-fold against RSV-A and 10.6- and 13.2-fold against RSV-B, respectively, 1 month postvaccination and remained 8.9-10.0-fold over prevaccination at day 43 postdelivery; (2) nAb titers were consistently higher compared to placebo recipients; (3) placental transfer ratios for anti-RSVPreF3 antibodies at birth were 1.62 and 1.90, respectively, and (4) nAb levels in infants were highest at birth and declined through day 181 postbirth. CONCLUSIONS: RSVPreF3 maternal vaccination had an acceptable safety risk profile and induced robust RSV-specific immune responses with successful antibody transfer to their newborns. CLINICAL TRIALS REGISTRATION: NCT04126213.

WHAT IS THE CONTEXT?: Infants, especially those less than 6 months of age, are at increased risk of lung infection caused by respiratory syncytial virus (RSV). However, this risk could be reduced with maternal vaccination against RSV during pregnancy. A previous clinical trial found that a vaccine candidate (named RSVPreF3) was well tolerated when given to non-pregnant women. WHAT IS NEW?: In pregnant women, RSVPreF3 was also well tolerated. Occurrence of unsolicited adverse events was similar between vaccine and placebo recipients. None of the serious adverse events or events of interest for pregnant women or newborns were considered related to the study intervention. One month after vaccination, mothers who received RSVPreF3 had 11­15 times higher levels of antibodies against RSV than before vaccination. These antibody levels remained similar until 43 days after delivery. In the infants born to mothers vaccinated during pregnancy with RSVPreF3, antibody levels were highest at birth, when levels were higher than in their mothers, and declined through day 181 postbirth. WHAT IS THE IMPACT?: RSVPreF3 had an acceptable safety risk profile in pregnant women and their babies. This vaccine induced potent immune responses against RSV, with maternal antibodies transferred to infants of the vaccinated mothers.

Facilitating safety evaluation in maternal immunization trials: a retrospective cohort study to assess pregnancy outcomes and events of interest in low-risk pregnancies in England.

BACKGROUND: Maternal characteristics like medical history and health-related risk factors can influence the incidence of pregnancy outcomes and pregnancy-related events of interest (EIs). Data on the incidence of these endpoints in low-risk pregnant women are needed for appropriate external safety comparisons in maternal immunization trials. To address this need, this study estimated the incidence proportions of pregnancy outcomes and pregnancy-related EIs in different pregnancy cohorts (including low-risk pregnancies) in England, contained in the Clinical Practice Research Datalink (CPRD) Pregnancy Register linked to Hospital Episode Statistics (HES) between 2005 and 2017. METHODS: The incidence proportions of 7 pregnancy outcomes and 15 EIs were calculated for: (1) all pregnancies (AP) represented in the CPRD Pregnancy Register linked to HES (AP cohort; N = 298 155), (2) all pregnancies with a gestational age (GA) ≥ 24 weeks (AP24+ cohort; N = 208 328), and (3) low-risk pregnancies (LR cohort; N = 137 932) with a GA ≥ 24 weeks and no diagnosis of predefined high-risk medical conditions until 24 weeks GA. RESULTS: Miscarriage was the most common adverse pregnancy outcome in the AP cohort (1 379.5 per 10 000 pregnancies) but could not be assessed in the other cohorts because these only included pregnancies with a GA ≥ 24 weeks, and miscarriages with GA ≥ 24 weeks were reclassified as stillbirths. Preterm delivery (< 37 weeks GA) was the most common adverse pregnancy outcome in the AP24+ and LR cohorts (742.9 and 680.0 per 10 000 pregnancies, respectively). Focusing on the cohorts with a GA ≥ 24 weeks, the most common pregnancy-related EIs in the AP24+ and LR cohorts were fetal/perinatal distress or asphyxia (1 824.3 and 1 833.0 per 10 000 pregnancies), vaginal/intrauterine hemorrhage (799.2 and 729.0 per 10 000 pregnancies), and labor protraction/arrest disorders (752.4 and 774.5 per 10 000 pregnancies). CONCLUSIONS: This study generated incidence proportions of pregnancy outcomes and pregnancy-related EIs from the CPRD for different pregnancy cohorts, including low-risk pregnancies. The reported incidence proportions of pregnancy outcomes and pregnancy-related EIs are largely consistent with external estimates. These results may facilitate the interpretation of safety data from maternal immunization trials and the safety monitoring of maternal vaccines. They may also be of interest for any intervention studied in populations of pregnant women.

Three Dose Levels of a Maternal Respiratory Syncytial Virus Vaccine Candidate Are Well Tolerated and Immunogenic in a Randomized Trial in Nonpregnant Women.

BACKGROUND: Respiratory syncytial virus (RSV) causes respiratory tract infections, which may require hospitalization especially in early infancy. Transplacental transfer of RSV antibodies could confer protection to infants in their first months of life. METHODS: In this first-in-human, placebo-controlled study, 502 healthy nonpregnant women were randomized 1:1:1:1 to receive a single dose of unadjuvanted vaccine containing 30/60/120 µg of RSV fusion (F) protein stabilized in the prefusion conformation (RSVPreF3) or placebo. RESULTS: Solicited local adverse events (AEs) were more frequently reported in the RSVPreF3 groups (4%-53.2%) versus placebo (0%-15.9%); most were mild/moderate. Unsolicited AEs were comparably reported among groups. Three serious AEs were reported; none was vaccination-related. Compared with prevaccination values, anti-RSV A neutralizing antibody geometric mean titers and anti-RSVPreF3 immunoglobulin G geometric mean concentrations increased 8- to 14-fold and 12- to 21-fold at day 8 and persisted 5- to 6-fold and 6- to 8-fold higher until day 91 in the RSVPreF3 groups versus 1-fold in placebo. Comparisons at day 8 and day 31 showed that the higher dose levels were significantly more immunogenic than the lowest one. CONCLUSIONS: The RSVPreF3 vaccine was well tolerated and immunogenic. The 60 and 120 µg dose levels were selected for further investigation in pregnant women. CLINICAL TRIALS REGISTRATION: NCT03674177.

Correlation of protection against varicella in a randomized Phase III varicella-containing vaccine efficacy trial in healthy infants.

BACKGROUND: Varicella vaccination confers high and long-lasting protection against chickenpox and induces robust immune responses, but an absolute correlate of protection (CoP) against varicella has not been established. This study models the relationship between varicella humoral response and protection against varicella. METHODS: This was a post-hoc analysis of data from a Phase IIIb, multicenter, randomized trial (NCT00226499) conducted in ten varicella-endemic European countries. Healthy children aged 12-22 months were randomized 3:3:1 to receive one dose of measles-mumps-rubella and one dose of varicella vaccine (one-dose group) or two doses of measles-mumps-rubella-varicella vaccine (two-dose group) or two doses of measles-mumps-rubella vaccine (control group) six weeks apart. The study remained observer-blind until completion, except in countries with obligatory additional immunizations. The objective was to correlate varicella-specific antibody concentrations with protection against varicella and probability of varicella breakthrough, using Cox proportional hazards and Dunning and accelerated failure time statistical models. The analysis was guided by the Prentice framework to explore a CoP against varicella. RESULTS: The trial included 5803 participants, 5289 in the efficacy (2266: one-dose group, 2279: two-dose group and 744: control group) and 5235 (2248, 2245 and 742 in the same groups) in the immunogenicity cohort. The trial ended in 2016 with a median follow-up time of 9.8 years. Six weeks after vaccination with one- or two-dose varicella-containing vaccine, more than 93.0% of vaccinees were seropositive for varicella-specific antibodies. Estimated vaccine efficacy correlated positively with antibody concentrations. The fourth Prentice CoP criterion was not met, due to predicted positive vaccine efficacy in seronegative participants. Further modelling showed decreased probability of moderate to severe varicella breakthrough with increasing varicella-specific antibody concentrations (ten-year probability <0.1 for antibody concentrations ≥2-fold above the seropositivity cut-off). CONCLUSIONS: Varicella-specific antibody concentrations are a good predictor of protection, given their inverse correlation with varicella occurrence. CLINICAL TRIAL: NCT00226499.

Association of Group B Streptococcus (GBS) Serum Serotype-Specific Anticapsular Immunoglobulin G Concentration and Risk Reduction for Invasive GBS Disease in South African Infants: An Observational Birth-Cohort, Matched Case-Control Study.

BACKGROUND: Licensure of a group B Streptococcus (GBS) polysaccharide-protein conjugate vaccine for protecting infants against invasive GBS disease (IGbsD) will likely need to be based on demonstrating vaccine safety in pregnant women, and benchmarking immunogenicity against a serological threshold associated with risk reduction of IGbsD. We investigated the association between naturally derived GBS serotype Ia and III IgG and risk reduction of IGbsD in infants ≤90 days of age. METHODS: In a matched case-control study, IGbsD cases were identified from a cohort of 38 233 mother-newborn dyads. Mothers colonized vaginally with serotype Ia or III at birth and their healthy infants were eligible as matched controls. GBS serotype-specific anticapsular immunoglobulin G (IgG) was measured on maternal and cord blood/infant sera by multiplex Luminex assay, and the IgG threshold associated with 90% risk reduction of IGbsD was derived by estimating absolute disease risk. RESULTS: In infants born at ≥34 weeks' gestational age, cord-blood IgG geometric mean concentrations (GMCs) were lower in cases than controls for serotypes Ia (0.05 vs 0.50 µg/mL; P = .004) and III (0.20 vs 0.38 µg/mL; P = .078). Cord-blood IgG concentrations ≥1.04 and ≥1.53 µg/mL were associated with 90% risk reduction of serotype Ia and III IGbsD, respectively. The maternal sera IgG threshold associated with 90% risk reduction was ≥2.31 µg/mL and ≥3.41 µg/mL for serotypes Ia and III, respectively. CONCLUSIONS: The threshold associated with a reduced risk for serotype Ia and III IGbsD identified on infant sera supports the case for licensure of a GBS polysaccharide-protein conjugate vaccine based on an immunogenicity evaluation benchmarked against the defined thresholds. CLINICAL TRIALS REGISTRATION: NCT02215226.

Safety and immunogenicity of an investigational maternal trivalent group B streptococcus vaccine in pregnant women and their infants: Results from a randomized placebo-controlled phase II trial.

BACKGROUND: This study evaluated the safety and immunogenicity of an investigational trivalent group B streptococcus (GBS) vaccine in US pregnant women, transplacental serotype-specific antibody transfer and persistence in infants, and serotype-specific antibodies in breast milk. METHODS: This randomized, observer-blind, placebo-controlled trial administered one dose of trivalent GBS vaccine (n = 49) or placebo (n = 26) to healthy pregnant 18-40-year-old women at 240/7-346/7 weeks' gestation. Women were enrolled from March 2014 to August 2015. Safety follow-up continued through postpartum day 180. Primary immunogenicity objectives were to evaluate serotype Ia/Ib/III-specific immunoglobulin G (IgG) levels in sera from women on day 1 (pre-vaccination), day 31, delivery and postpartum days 42 and 90, and from infants at birth (cord blood), days 42 and 90. Antibody transfer ratios (cord blood/maternal sera at delivery) and serotype-specific secretory immunoglobulin A (sIgA) and IgG in breast milk after delivery and on postpartum days 42 and 90 were evaluated. The planned sample size was not based on statistical assumptions for this descriptive study. RESULTS: Baseline characteristics were similar between groups. Serious adverse events were reported for 16% of GBS-vaccinated women and 15% of their infants, and 15% of placebo recipients and 12% of their infants; none were fatal or deemed vaccine-related. Serotype-specific IgG geometric mean concentrations (GMCs) were 13-23-fold higher in vaccine vs placebo recipients on day 31 and persisted until postpartum day 90. Median antibody concentrations were substantially higher in women with detectable pre-vaccination antibody concentrations. Antibody transfer ratios in the vaccine group were 0.62-0.82. Infant IgG GMCs and breast milk sIgA GMCs were higher in the vaccine vs the placebo group at all timepoints. CONCLUSIONS: Maternal immunization with the trivalent GBS vaccine in US women had a favorable safety profile, elicited antibodies that were transplacentally transferred and persisted in infants for a minimum of 3 months. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT02046148.

Safety and immunogenicity of fully liquid and lyophilized formulations of an investigational trivalent group B streptococcus vaccine in healthy non-pregnant women: Results from a randomized comparative phase II trial.

BACKGROUND: We evaluated the safety and immunogenicity of liquid and lyophilized formulations of an investigational trivalent group B streptococcus (GBS) vaccine in non-pregnant women and assessed the formulations' equivalence in terms of serotype-specific immune response. METHODS: This phase II, randomized, comparative, observer-blind trial enrolled healthy non-pregnant women 18-40 years of age. Women received a single dose of fully liquid (n = 529) or lyophilized (n = 521) trivalent GBS vaccine on day 1. Safety assessments were performed up to day 181 (study termination). Serotype Ia/Ib/III-specific immunoglobulin G (IgG) antibodies were measured in sera from women on day 1 (pre-vaccination) and day 31. Equivalence between the two formulations was demonstrated if the two-sided 95% confidence interval (CI) for the ratio (liquid/lyophilized) of the geometric mean concentrations (GMCs) on day 31 was contained in a (0.5, 2.0) interval for each serotype. RESULTS: Solicited and unsolicited adverse events were reported at similar rates for both formulations. Serious adverse events were reported for six (1.1%) liquid GBS and nine (1.7%) lyophilized GBS vaccinated women, none of which were considered related to vaccination or fatal. On day 31, serotype-specific IgG concentrations were 8-16-fold higher than on day 1 in both groups. Equivalence of the liquid to the lyophilized formulation 30 days post-vaccination was demonstrated as the 95% CIs of the GMC ratios were within the pre-specified interval for the three serotypes: GMC ratios were 1.02 (95% CI: 0.79, 1.32) for serotype Ia, 0.93 (0.71, 1.21) for serotype Ib and 0.99 (0.76, 1.30) for serotype III. CONCLUSIONS: Both formulations of the investigational trivalent GBS vaccine had favorable safety profiles and induced similar GBS serotype-specific antibody concentrations. This study demonstrated that the fully liquid formulation was equivalent to the lyophilized formulation in healthy non-pregnant women in terms of immunogenicity for all three serotypes. CLINICAL TRIALS REGISTRATION: NCT02270944.

Safety and Immunogenicity of a Second Dose of an Investigational Maternal Trivalent Group B Streptococcus Vaccine in Nonpregnant Women 4-6 Years After a First Dose: Results From a Phase 2 Trial.

BACKGROUND: Maternal immunization against group B streptococcus (GBS) could protect infants from invasive GBS disease. Additional doses in subsequent pregnancies may be needed. We evaluated the safety and immunogenicity of a second dose of an investigational trivalent CRM197-glycoconjugate GBS vaccine (targeting serotypes Ia/Ib/III), administered to nonpregnant women 4-6 years postdose 1. METHODS: Healthy women either previously vaccinated with 1 dose of trivalent GBS vaccine 4-6 years before enrollment (n = 53) or never GBS vaccinated (n = 27) received a single trivalent GBS vaccine injection. Adverse events (AEs) were recorded. Serotype-specific (Ia/Ib/III) anti-GBS antibodies were measured by multiplex immunoassay prevaccination and 30/60 days postvaccination. RESULTS: AEs were reported with similar rates after a first or second dose; none were serious. Of previously GBS-vaccinated women, 92%-98% had anti-GBS concentrations that exceeded an arbitrary threshold (8 µg/mL) for each serotype 60 days postdose 2 vs 36%-56% postdose 1 in previously non-GBS-vaccinated women. Of previously GBS-vaccinated women with undetectable baseline (predose 1) anti-GBS levels, 90%-98% reached this threshold postdose 2. For each serotype, anti-GBS geometric mean concentrations (GMCs) 30/60 days postdose 2 in previously GBS-vaccinated women were ≥200-fold higher than baseline GMCs. Among women with undetectable baseline anti-GBS levels, postdose 2 GMCs in previously GBS-vaccinated women exceeded postdose 1 GMCs in previously non-GBS-vaccinated women (≥7-fold). CONCLUSIONS: A second trivalent GBS vaccine dose administered 4-6 years postdose 1 was immunogenic with a favorable safety profile. Women with undetectable preexisting anti-GBS concentrations may benefit from a sufficiently spaced second vaccine dose. CLINICAL TRIALS REGISTRATION: NCT02690181.

Immunogenicity and Safety of a Measles-Mumps-Rubella Vaccine Administered as a First Dose to Children Aged 12 to 15 Months: A Phase III, Randomized, Noninferiority, Lot-to-Lot Consistency Study.

BACKGROUND: MMR II (M-M-R II [Merck & Co, Inc.]) is currently the only measles, mumps, and rubella (MMR) vaccine licensed in the United States. A second MMR vaccine would mitigate the potential risk of vaccine supply shortage or delay. In this study, we assessed the immunogenicity and safety of another MMR vaccine (MMR-RIT [Priorix, GlaxoSmithKline]) compared with those of the MMR II in 12- to 15-month-old children who received it as a first dose. METHODS: In this phase III, observer-blinded, noninferiority, lot-to-lot consistency clinical trial (ClinicalTrials.gov identifier NCT01702428), 5003 healthy children were randomly assigned to receive 1 dose of MMR-RIT (1 of 3 production lots) or MMR II along with other age-recommended routine vaccines. We evaluated the immunogenicity of all vaccines in terms of antibody concentrations (by using an enzyme-linked immunosorbent assay or electrochemiluminescence assay) and/or seroresponse rates 43 days after vaccination. We also assessed the reactogenicity and safety of the vaccines. RESULTS: Immunoresponses after vaccination with MMR-RIT were robust and noninferior to those after vaccination with the MMR II. Immunogenicity of the 3 production lots of MMR-RIT was consistent; more than 97% of the children had a seroresponse to MMR components. The coadministered vaccines elicited similar immunoresponses in the MMR-RIT and MMR II groups. Both MMR vaccines resulted in comparable reactogenicity profiles, and no safety concerns were detected. CONCLUSIONS: If licensed, the MMR-RIT could provide a valid option for the prevention of measles, mumps, and rubella in children in the United States and would reduce potential risks of a vaccine shortage.

Protection against varicella with two doses of combined measles-mumps-rubella-varicella vaccine or one dose of monovalent varicella vaccine: 10-year follow-up of a phase 3 multicentre, observer-blind, randomised, controlled trial.

BACKGROUND: The duration of protection provided by varicella vaccines is unclear. We assessed the 10-year vaccine efficacy of two doses of a combined measles-mumps-rubella-varicella vaccine (MMRV), one live attenuated varicella vaccine (V) dose given after one measles-mumps-rubella vaccine (MMR) dose (MMR + V), versus two MMR doses (control vaccine) for the prevention of confirmed varicella. METHODS: This was a phase 3b follow-up of an observer-blinded, randomised, controlled trial. In phase a, children aged 12-22 months (at first vaccination) from Czech Republic (Czechia), Greece, Italy, Lithuania, Norway, Poland, Romania, Russia, Slovakia, and Sweden were randomly assigned by computer-generated randomisation list (3:3:1) to receive two doses of MMRV, one dose of MMR and one dose of varicella vaccine, or two doses of MMR, 42 days apart. Varicella cases were confirmed by detection of viral DNA, or epidemiological link and clinical assessment, by an independent data monitoring committee; disease severity was based on a modified Vázquez scale. Hazard ratios for MMRV and MMR + V versus MMR estimated in the per-protocol cohort using a Cox proportional hazards regression model were used to calculate vaccine efficacy and 95% CI. Serious adverse events were recorded throughout the study in all vaccinated children. Study objectives were secondary and descriptive. The trial is registered at ClinicalTrials.gov, number NCT00226499. FINDINGS: Between Sept 1, 2005, and May 10, 2006, 5803 children (mean age 14·2 months, SD 2·5) were vaccinated. The per-protocol cohort included 2279 children from the MMRV group, 2266 from the MMR + V group, and 744 from the MMR group. From baseline to a median follow-up of 9·8 years, 76 (3%) children in the MMRV group, 469 (21%) in the MMR + V group, and 352 (47%) in the MMR group had varicella. Vaccine efficacy against all varicella was 95·4% (95% CI 94·0-96·4) for MMRV and 67·2% (62·3-71·5) for MMR + V; vaccine efficacy against moderate or severe varicella was 99·1% (97·9-99·6) for MMRV and 89·5% (86·1-92·1) for MMR + V. During phase b, serious adverse events were reported by 290 (15%) of 1961 children in the MMRV group, 317 (16%) of 1978 in the MMR + V group, and 93 (15%) of 641 in the MMR group. There were no treatment-related deaths. INTERPRETATION: The 10-years vaccine efficacy observed, suggests that a two-dose schedule of varicella vaccine provided optimum long-term protection for the prevention of varicella by offering individual protection against all severities of disease and leading to a potential reduction in transmission, as observed in the US experience with universal mass vaccination. FUNDING: GlaxoSmithKline Biologicals.

Safety and immunogenicity of a varicella vaccine without human serum albumin (HSA) versus a HSA-containing formulation administered in the second year of life: a phase III, double-blind, randomized study.

BACKGROUND: A new formulation of the live-attenuated varicella vaccine Varilrix (GSK) produced without human serum albumin (HSA) was developed to minimize a theoretical risk of transmission of infectious diseases. A previous study showed that the vaccine was immunologically non-inferior to the HSA-containing vaccine and well-tolerated in toddlers; low-grade fever was numerically higher in children receiving the vaccine without HSA, but the study lacked power to conclude on this difference. METHODS: In this phase III, double-blind, multi-center study, healthy 12-23-month-olds were randomized (1:1) to receive two doses of the varicella vaccine without (Var-HSA group) or with HSA (Var + HSA group) at days 0 and 42. The primary objective compared safety of the vaccines in terms of incidence of fever > 39.0 °C in the 15-day period post-first vaccination. The objective was considered met if the upper limit of the 95% confidence interval for the between-group difference in the incidence of fever > 39.0 °C was ≤5% (Var-HSA group minus Var + HSA group). Safety, reactogenicity and immune responses were evaluated. RESULTS: Six hundred fifteen children in the Var-HSA group and 616 in the Var + HSA group received ≥1 vaccination. Fever > 39.0 °C was reported in 3.9 and 5.2% of participants in the Var-HSA and Var + HSA groups, with a between-group difference of - 1.29 (95% confidence interval: - 3.72-1.08); therefore, the primary objective was achieved. Fever rates post-each dose and the incidence of solicited local and general adverse events (AEs) were comparable between groups. Unsolicited AEs were reported for 43.9 and 36.5% of children in the Var-HSA group and 45.8 and 36.0% of children in the Var + HSA group, during 43 days post-dose 1 and 2, respectively. Serious AEs occurred in 2.1% (group Var-HSA) and 2.4% (group Var + HSA) of children, throughout the study. In a sub-cohort of 364 children, all had anti-varicella-zoster virus antibody concentrations ≥50 mIU/mL post-dose 2; comparable geometric mean concentrations were observed between the groups. CONCLUSIONS: The varicella vaccine formulated without HSA did not induce higher rates of fever during the 15 day-post-vaccination period, as compared with the original HSA-containing vaccine. The two vaccines displayed similar safety and immunogenicity profiles in toddlers. TRIAL REGISTRATION: NCT02570126 , registered on 5 October 2015 (www.clinicaltrials.gov).

Immunogenicity and safety of a second dose of a measles-mumps-rubella vaccine administered to healthy participants 7 years of age or older: A phase III, randomized study.

The introduction of vaccination programs against measles, mumps, and rubella (MMR) led to significant global reduction in morbidity and mortality from these diseases. The currently recommended MMR vaccination schedule in the United States of America comprises 2 vaccine doses typically administered at 12-15 months and 4-6 years, respectively. Considering recent outbreaks in the USA, catch-up vaccination with an additional dose of MMR vaccine could contribute to outbreak control and community protection. This phase III, observer-blind, randomized controlled trial (NCT02058563) assessed the immunogenicity and safety of a dose of the MMR-RIT vaccine (Priorix, GSK) compared to MMR II vaccine (control; M-M-R II, Merck&Co Inc.) in ≥7-year-olds who had received ≥1 previous dose of MMR vaccine. We assessed anti-measles, anti-mumps, and anti-rubella antibody geometric mean concentrations (GMCs; primary endpoint) and seroresponse rates (SRRs) at day 42 post-vaccination. Solicited, unsolicited, and serious adverse events (AEs) were recorded. The according-to-protocol cohort for immunogenicity included 869 participants (MMR-RIT: N = 433; MMR II: N = 436). We observed anti-measles, anti-mumps, and anti-rubella antibody GMCs of 1790.2 mIU/mL, 113.5 EU/mL, and 76.1 IU/mL, respectively, and SRRs of 98.8%, 98.4%, and 99.5%, respectively, after a dose of MMR-RIT; non-inferiority compared to MMR II was demonstrated. Both vaccines showed comparable reactogenicity profiles; the most common solicited AEs were injection site redness and pain, and fever (MMR-RIT: 12.2%, 11.8%, and 3.0%; MMR II: 11.7%, 11.5%, and 5.2%, respectively). The dose of MMR-RIT induced robust immune responses that were not inferior to those of MMR II, and was well tolerated.

One or two doses of live varicella virus-containing vaccines: Efficacy, persistence of immune responses, and safety six years after administration in healthy children during their second year of life.

BACKGROUND: This phase III B follow-up of an initial multicenter study (NCT00226499) will evaluate the ten-year efficacy of two doses of the combined measles-mumps-rubella-varicella vaccine (MMRV) and one dose of the live attenuated varicella vaccine (V) versus a measles-mumps-rubella control group (MMR) for the prevention of clinical varicella disease. Here we present efficacy results for six years post-vaccination. METHODS: In phase A of the study, healthy children aged 12-22 months from ten European countries were randomized (3:3:1) and received either two doses of MMRV, or one dose of combined MMR and one dose of monovalent varicella vaccine (MMR+V), or two doses of the MMR vaccine (control), 42 days apart. Vaccine efficacy against all and against moderate or severe varicella (confirmed by detection of viral DNA or epidemiological link) was assessed from six weeks up to six years post-dose 2 for the MMRV and MMR+V groups, and was calculated with 95% confidence intervals (CI). The severity of varicella was calculated using the modified Vázquez scale (mild ≤ 7; moderately severe = 8-15; severe ≥ 16). Herpes zoster cases were also recorded. RESULTS: 5289 children (MMRV = 2279, mean age = 14.2, standard deviation [SD] = 2.5; MMR+V = 2266, mean age = 14.2, SD = 2.4; MMR = 744, mean age = 14.2, SD = 2.5 months) were included in the efficacy cohort. 815 varicella cases were confirmed. Efficacy of two doses of MMRV against all and against moderate or severe varicella was 95.0% (95% CI: 93.6-96.2) and 99.0% (95% CI: 97.7-99.6), respectively. Efficacy of one dose of varicella vaccine against all and against moderate or severe varicella was 67.0% (95% CI: 61.8-71.4) and 90.3% (95% CI: 86.9-92.8), respectively. There were four confirmed herpes zoster cases (MMR+V = 2, MMR = 2), all were mild and three tested positive for the wild-type virus. CONCLUSIONS: Two doses of the MMRV vaccine and one dose of the varicella vaccine remain efficacious through six years post-vaccination.

Pain caused by measles, mumps, and rubella vaccines: A systematic literature review.

PURPOSE: The risk of post-vaccination adverse events (AEs) is a primary public health concern. Among the AEs, pain is a significant source of anxiety for both children and their parents. This review describes and assesses the intensity of pain experienced by children post-vaccination with widely used Measles-Mumps-Rubella (MMR) vaccines. METHODS: A systematic literature search was conducted in Pubmed, Embase and Cochrane to identify publications describing immediate pain at injection site (primary objective) or pain within days (secondary objective) after 2 specific MMR vaccines. Immediate pain ('acute pain' according to the Brighton Collaboration case definition) was defined as pain occurring at the time or within 5min of injection. RESULTS: Four studies, which compared the intensity of immediate injection site pain experienced by children after MMR vaccination, were identified. Various pain assessment tools and methods were used to quantify the intensity of pain, including the median difference in Visual Analog Scale scores between vaccine groups. All four studies showed significantly less immediate pain caused by Priorix (GSK Vaccines) compared with M-M-R II (Merck & Co., Inc.). CONCLUSIONS: To our knowledge, this review summarizes for the first time the available scientific evidence on the intensity of pain following different MMR vaccines. It highlights that MMR vaccines can differ in terms of immediate pain. Further research may be needed to better understand the underlying reason for this observation. In this context, it is very important to understand which physicochemical properties are most relevant for the immediate pain profile of a vaccine to thereby support the development of vaccines with the best possible immediate pain profile.

Two-year antibody persistence in children vaccinated at 12-15 months with a measles-mumps-rubella virus vaccine without human serum albumin.

One combined measles-mumps-rubella (MMR) vaccine without Human Serum Albumin (HSA) is currently licensed in the USA (M-M-R II; Merck, USA) and another has been developed (Priorix™ [MMR-RIT, GSK, Belgium]). In this follow-up study, children from USA or Puerto Rico, who had received one dose of M-M-R II or MMR-RIT at 12-15 months of age in the primary study (NCT00861744), were followed-up for 2 y post-vaccination. Anti-measles and anti-rubella antibodies were measured using Enzyme-Linked Immunosorbent Assay (ELISA), and anti-mumps antibodies using ELISA and plaque reduction neutralization (PRN) assays. Serious adverse events (SAEs) were recorded during the entire follow-up. The according-to-protocol (ATP) persistence cohort included 752 children (M-M-R II = 186, MMR-RIT = 566), who received primary vaccination at a mean age of 12.3 ( ± 0.67) months. 104 children were revaccinated with MMR-containing vaccines; therefore, serology results for timepoints after revaccination were excluded from the analysis. Seropositivity for measles (Year 1≥ 98.3%; Year 2≥ 99.4%) and rubella (Year 1≥ 98.9%; Year 2 = 100%) remained as high at Year 2 as at Day 42. Similarly, seropositivity for mumps determined by ELISA (Year 1≥ 90.1%; Year 2≥ 94.1%) and PRN assays (Year 1≥ 87.5%; Year 2≥ 91.7%) persisted. Thirty-three SAEs were recorded in 23 children; 2 SAEs (inguinal adenitis and idiopathic thrombocytopenic purpura) and one SAE (febrile convulsion) were considered as potentially related to MMR-RIT and M-M-R II, respectively. This study showed that antibodies against measles, mumps and rubella persisted for up to 2 y post-vaccination with either MMR vaccine in children aged 12-15 months, and that both vaccines were well-tolerated during the follow-up period.

The immunogenicity and safety of a tetravalent measles-mumps-rubella-varicella vaccine when co-administered with conjugated meningococcal C vaccine to healthy children: A phase IIIb, randomized, multi-center study in Italy.

INTRODUCTION: Multiple vaccination visits and administrations can be stressful for infants, parents and healthcare providers. Multivalent combination vaccines can deliver the required number of antigens in fewer injections and clinic visits, while vaccine co-administration can also reduce the number of visits. This non-inferiority study was undertaken to evaluate the feasibility of co-administering a combined measles-mumps-rubella-varicella (MMRV) vaccine with conjugated meningococcal C (MenC) vaccine in a large cohort of healthy Italian toddlers. METHODS: Healthy subjects aged 13-15months were randomized (2:1:1) to receive single doses of either: co-administered MMRV+MenC at the same visit (MMRV+MenC group); or MMRV followed 42days later by MenC (MMRV group); or MenC followed 42days later by MMRV (MenC group). Blood samples were collected before and 43days after vaccination. Antibody titers against MMRV were measured using ELISA. Functional-anti-meningococcal-serogroup activity (rSBAMenC) was assessed using a serum bactericidal test. Solicited local and general reactions were recorded for up to 4 and 42days post-vaccination, respectively. Non-inferiority of MMRV+MenC to MMRV (post-dose-1 seroconversion rates) and MMRV+MenC to MenC (post-dose-1 seroprotection rates) was achieved if the lower limit (LL) of the 95% confidence interval (CI) for the group difference was ⩾-10% for each antigen. RESULTS: 716 subjects were enrolled in the study. At 42days post-vaccination, the MMRV seroconversion rates were 99.3% (measles), 94.5% (mumps), 100% (rubella) and 99.7% (varicella) in the MMRV+MenC group, and 99.4%, 93.2%, 100% and 100%, respectively, in the MMRV group. The seroprotection rates against rSBA-MenC were 98.3% in the MMRV+MenC group and 99.3% in the MenC group. Non-inferiority was reached for all the vaccine antigens. The safety profiles were as expected for these vaccines. CONCLUSION: The immune responses elicited by co-administered MMRV+MenC were non-inferior to those elicited by MMRV or MenC alone and support vaccination of children with both vaccines at a single visit. CLINICAL TRIALS REGISTRATION: NCT01506193.