Safety and immunogenicity of a seasonal trivalent inactivated split influenza vaccine: a double blind, phase III randomized clinical trial in healthy Serbian adults.

This study was a phase III, multicenter, double-blind, randomized, placebo-controlled trial to evaluate the safety and immunogenicity of a seasonal trivalent split, inactivated influenza vaccine (TIV) in healthy Serbian adults between the ages of 18 and 65 years. This egg-based vaccine was manufactured by the Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia. A total of 480 participants were assigned randomly in a ratio of 2:1 to receive a single intramuscular dose (0.5 ml) of the vaccine (15 µg of hemagglutinin per strain) or placebo (phosphate-buffered saline). Participants were monitored for safety, including solicited and unsolicited adverse events (AEs) and serious adverse events (SAEs). No SAEs related to vaccination were reported. Injection site pain (51.3%), injection site tenderness (40.4%), tiredness (17.0%), and headache (15.1%) were the most commonly reported solicited events in the vaccine group. Incidence of related unsolicited AEs was low (1.3%) among vaccinees. Hemagglutinin inhibition (HAI) titers were measured before and 21 days after vaccination in 151 participants. Overall, HAI seroconversion rates to H1 and H3 were observed in 90.1% and 76.2% of vaccinees, respectively. For B antigen, it was 51.5%, likely due to high pre-vaccination titers. Post-vaccination seroprotection rates were in the range of 78.2-95.0% for the three antigens. Post-vaccination geometric mean titers (GMT) were at least 3.8 times higher than baseline levels for all the three strains among vaccinees. Overall, the study showed that the vaccine was safe and well tolerated, and induced a robust immune response against all three vaccine strains. ClinicalTrials.gov identifier: NCT02935192, October 17, 2016.

A Phase III open-label, randomized, active controlled clinical study to assess safety, immunogenicity and lot-to-lot consistency of a bovine-human reassortant pentavalent rotavirus vaccine in Indian infants.

BACKGROUND: A heat-stable bovine-human rotavirus reassortant pentavalent vaccine (BRV-PV, ROTASIIL®) was developed in India. In this study, the vaccine was tested for safety, immunogenicity and clinical lot-to-lot consistency. METHODS: This was a Phase III, open label, randomized, equivalence design study. The primary objective was to demonstrate lot-to-lot consistency of BRV-PV. Subjects were randomized into four arms, three arms received Lots A, B, and C of BRV-PV and the control arm, received Rotarix®. Three doses of BRV-PV or two doses of Rotarix® and one dose of placebo were given at 6, 10, and 14 weeks of age. Blood samples were collected four weeks after the third dose to assess rotavirus IgA antibody levels. The three lots of BRV-PV were equivalent if the 95% Confidence Intervals (CIs) of the geometric mean concentration (GMC) ratios were between 0.5 and 2. Solicited reactions were collected by using diary cards. RESULTS: The study was conducted in 1500 randomized infants, of which 1341 infants completed the study. The IgA GMC ratios among the three lots were around 1 (Lot A versus Lot B: 1.07; Lot A versus Lot C: 1.06; and Lot B versus Lot C: 0.99). The 95% CIs for the GMC ratios were between 0.78 and 1.36. The IgA GMCs were: BRV-PV group 19.16 (95% CI 17.37-21.14) and Rotarix® group 10.92 (95% CI 9.36-12.74) (GMC ratio 1.75; 90% CI 1.51-2.04). Seropositivity rates were 46.98% (95% CI 43.86-50.11) and 31.12% (95% CI 26.17-36.41). The incidence of solicited reactions was comparable across the four arms. No serious adverse events were associated with the study vaccines, except two gastroenteritis events in the BRV-PV groups. CONCLUSION: Lot-to-lot consistency of BRV-PV was demonstrated in terms of GMC ratios of IgA antibodies. The vaccine safety and immunogenicity profiles were similar to those of Rotarix®. Clinical Trials.Gov [NCT02584816] and Clinical Trial Registry of India [CTRI/2015/07/006034].

Non-interference of Bovine-Human reassortant pentavalent rotavirus vaccine ROTASIIL® with the immunogenicity of infant vaccines in comparison with a licensed rotavirus vaccine.

BACKGROUND: A newly developed bovine-human reassortant pentavalent vaccine (BRV-PV, ROTASIIL®) was tested for its potential effect on the immunogenicity of concomitantly administered EPI vaccines in infants in a randomized controlled study in India. METHODS: In this Phase III, multicenter, open label, randomized, controlled study, three doses of BRV-PV or two doses of Rotarix® and one dose of placebo were given to healthy infants at 6, 10, and 14 weeks of age. Subjects also received three doses of DTwP-HepB-Hib (diphtheria, tetanus, whole-cell pertussis, hepatitis B, and haemophilus influenzae type b conjugate - pentavalent vaccine) and oral polio vaccine concomitantly at 6, 10, and 14 weeks of age and a single dose of inactivated polio vaccine at 14 weeks of age. Blood samples were collected four weeks after the final vaccination to assess immune responses to all the vaccines administered. For diphtheria, tetanus, hepatitis B, Hib, polio type 1, and polio type 3 antibodies, non-interference was to be supported if the lower limit of the two-sided 90% confidence interval (CI) for the seroprotection rate difference for the BRV-PV group minus the Rotarix® group was >10.0%. For pertussis antibodies, non-interference was to be supported if the lower limit of the two-sided 90% CI for the ratio of geometric mean concentrations (GMCs) was >0.5. RESULTS: A total of 1500 infants were randomized to either BRV-PV (1125 infants) or Rotarix® (375 infants), of which 1341 completed the study as per the protocol. More than 97% of subjects achieved seroprotective antibody titres against diphtheria, tetanus, hepatitis B, Hib, polio type 1, and polio type 3 in both groups. The difference in seroprotection rates between the BRV-PV group and the Rotarix® group for all these antibodies was less than 1%. The ratio of GMCs of anti-pertussis IgG concentrations for the BRV-PV group versus Rotarix® was 1.04 [90% CI: 0.90; 1.19]. CONCLUSION: BRV-PV does not interfere with the immunogenicity of concomitantly administered routine infants vaccines.

Immunogenicity and reactogenicity of the human rotavirus vaccine, RIX4414 oral suspension, when co-administered with routine childhood vaccines in Chinese infants.

This study evaluated the immunogenicity of the human rotavirus (RV) vaccine (RIX4414) when co-administered with routine childhood vaccines in Chinese infants (NCT01171963). Healthy infants aged 6-16 weeks received 2 doses of either RIX4414 or placebo according to a 0, 1-month schedule. Infants received routine diphtheria-tetanus-acellular pertussis (DTPa) and oral poliovirus (OPV) vaccines either separately from or concomitantly with RIX4414/placebo (separate and co-administration cohorts, respectively). Anti-RV IgA seroconversion rates (one month post-dose-2) and seropositivity rates (at one year of age) were measured using ELISA. Immune responses against the DTPa and OPV antigens were measured one month post-DTPa dose-3 in the co-administration cohort. Solicited local and general symptoms were recorded for 8-days post-vaccination (total cohort). The according-to-protocol immunogenicity population included 511 infants in the separate cohort and 275 in the co-administration cohort. One month post-RIX4414 dose-2, anti-RV IgA seroconversion rates were 74.7% (95% confidence interval [CI]: 68.9-79.9) and 64.2% (95% CI: 55.4-72.3) in the separate and co-administration cohorts; seropositivity rates at one year of age were 71.5% (95% CI: 65.5-77.1) and 50.0% (95% CI: 40.9-59.1), respectively. One month post-DTPa dose-3, all infants in the co-administration cohort were seroprotected against diphtheria and tetanus, and seropositive for pertussis toxoid, pertactin and filamentous haemaglutinin. Two months post-OPV dose-3, seroprotection rates against anti-poliovirus types 1, 2 and 3 were >99% in the co-administration cohort. Reactogenicity profiles were similar in both cohorts. RIX4414 was immunogenic and well-tolerated in Chinese infants and did not appear to interfere with the immunogenicity and reactogenicity of co-administered routine childhood vaccines.

Immunogenicity and reactogenicity of a decennial booster dose of a combined reduced-antigen-content diphtheria-tetanus-acellular pertussis and inactivated poliovirus booster vaccine (dTpa-IPV) in healthy adults.

BACKGROUND: Pertussis in adults and adolescents could be reduced by replacing traditional tetanus and diphtheria (Td) boosters with reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) vaccines. This study evaluated the administration of dTpa-IPV (dTpa-inactivated poliovirus) in adults ten years after they received a booster dose of either dTpa-IPV, dTpa+IPV or Td-IPV in trial NCT01277705. METHODS: Open multicentre, phase IV study (www.clinicaltrials.govNCT01323959) in which healthy adults, who had received a previous dose of dTpa-IPV, dTpa+IPV or Td-IPV ten years earlier, received a single decennial booster dose of dTpa-IPV (Boostrix-polio, GlaxoSmithKline Vaccines). Blood samples were collected before and one month after booster vaccination. Antibody concentrations against all vaccine antigens were measured and reactogenicity and safety were assessed. RESULTS: A total of 211 subjects (mean age 50.3 years) received vaccination of whom 201 were included in the according-to-protocol cohort for immunogenicity. Before the decennial dTpa-IPV booster, ≥71.0% subjects were seroprotected/seropositive against all vaccine antigens. One month after the booster dose, all subjects were seroprotected against tetanus and poliovirus types 2 and 3; ≥95.7% subjects were seroprotected against diphtheria and ≥98.3% against poliovirus type 1. Anti-pertussis booster responses for the various antigens were observed in ≥76.5% (pertussis toxoid; PT), ≥85.1% (filamentous haemagglutinin; FHA) and ≥63.2% (pertactin; PRN) of subjects. During the 4-day follow-up, the overall incidence of local AEs was 71.6%, 75.0% and 72.2% in dTpa-IPV, dTpa+IPV and Td-IPV groups, respectively. Pain was the most frequent solicited local adverse event (AE; ≥62.7% subjects) and fatigue the most frequent solicited general AE (≥18.5%). No serious AEs were reported during the study. CONCLUSION: A booster dose of dTpa-IPV was immunogenic and well tolerated in adults who had received a booster dose of either dTpa-IPV, dTpa+IPV or Td-IPV, ten years previously and supports the repeated administration of dTpa-IPV.

Decennial administration in young adults of a reduced-antigen content diphtheria, tetanus, acellular pertussis vaccine containing two different concentrations of aluminium.

BACKGROUND: Regular booster vaccination might be necessary throughout life to protect against pertussis infection. Nevertheless the duration of protection after booster vaccination remains unclear. In this study, antibody persistence up to 10 years after previous vaccination of adolescents (N=478) with combined reduced-antigen-content diphtheria-tetanus-acellular pertussis vaccine (dTpa, Boostrix™, GlaxoSmithKline Belgium) containing 0.5mg, 0.3mg or 0.133mg of aluminium was assessed. The immunogenicity, reactogenicity and safety of a decennial booster dTpa dose were also investigated. METHODS: Young adults vaccinated as adolescents in the initial booster study were invited to participate in an assessment of antibody persistence at years 8.5 and 10, and to receive a dTpa booster dose at year 10 with immunogenicity assessment one month later. Those who originally received the 0.5mg or 0.3mg formulations received the same vaccine at year 10. Those in the 0.133mg group received the 0.5mg formulation. Reactogenicity and safety endpoints were captured until 30 days after booster vaccination. RESULTS: Prior to the decennial booster at year 8.5 and year 10, all participants had seroprotective antibodies for diphtheria (ELISA or neutralisation assay) and tetanus. At least 77.8% were seropositive for anti-pertussis toxin (PT) antibodies at year 8.5 and 82.8% at year 10. All participants were seropositive for antibodies for filamentous haemagglutinin and pertactin at both time points. The decennial booster dose induced robust increases in antibody GMCs to all antigens. The post-booster anti-PT geometric mean concentration was 82.5EL.U/ml (95%CI 67.0-101.6) and 124.0 (103.5-148.5) in the 0.3mg and 0.5mg groups, respectively. The reactogenicity and safety profile of the decennial booster dose was consistent with the known safety profile of dTpa. No serious adverse events were reported. CONCLUSIONS: Decennial booster vaccination with either of the two licensed formulations of dTpa was highly immunogenic and well tolerated in young adults. Either formulation could be confidently used as a decennial booster. This study is registered at www.clinicaltrials.govNCT01147900.

Human rotavirus vaccine (RIX4414) efficacy in the first two years of life: a randomized, placebo-controlled trial in China.

Rotaviruses (RV) are a major cause of severe gastroenteritis (GE) in children aged<5 y. For the first time in China, we assessed the efficacy of two oral doses of the human rotavirus vaccine (RIX4414) in infants during the first two years of life (113808/NCT01171963). Healthy infants aged 6-16 weeks were randomized (1:1) to receive two oral doses of either the RIX4414 vaccine/placebo according to a 0, 1 month schedule. Vaccine efficacy (VE) against severe RVGE was assessed from two weeks post-Dose 2 up until the end of the second RV season and calculated with its 95% confidence intervals (CI). The primary efficacy objective was met if the lower limit of the 95% CI on VE was ≥10%. Unsolicited symptoms reported during the 31-d post-vaccination follow-up period and serious adverse events (SAEs) reported throughout the study were assessed. Of 3333 enrolled infants, 3148 were included in the according-to-protocol efficacy cohort. Over two consecutive RV seasons, fewer severe RVGE episodes were reported in the RIX4414 group (n=21) vs. the placebo group (n=75). VE against severe RVGE was 72% (95% CI: 54.1-83.6); the lower limit of the 95% CI on VE was >10%. The number of unsolicited symptoms and SAEs reported was similar between both groups. Thirteen deaths (RIX4414=6; placebo=7) occurred during the study. All SAEs and deaths in the RIX4414 group were considered unrelated to vaccination. Two oral doses of RIX4414 vaccine provided a substantial level of protection against severe RVGE in Chinese children during the first two years of life.

Alteration of superoxide- and nitric oxide-mediated antimicrobial function of macrophages by in vivo cocaine exposure.

Cocaine is a popular drug of abuse and despite impressive advances in the understanding of its physiological, pharmacological, and toxic effects, its mechanism of immunosuppression at the cellular level is not well understood. In this paper we report the role of effector molecules like superoxide and nitric oxide in the antibacterial function of macrophages exposed to acute and chronic doses of cocaine in vivo. Bacterial killing by acute cocaine-exposed macrophages (ACE-Mphis) increased significantly, with a concomitant rise in respiratory burst and generation of superoxide and nitric oxide, compared with control macrophages. In contrast, chronic cocaine-exposed macrophages (CCE-Mphis) exhibited limited antimicrobial activity, which correlated closely with diminished respiratory burst and reduced production of superoxide and nitric oxide. Further, a killing assay was carried out in the presence of N(G)-methyl-L-arginine acetate, an inhibitor of iNOS, to evaluate the role of nitric oxide in the killing process. The results obtained indicate that while about 30% killing of input bacteria by control and ACE-Mphis was attributable to NO-mediated killing, only about 6% killing from NO was found with CCE-Mphis. The findings indicate that acute exposure to cocaine possibly caused upregulation of enzymes responsible for the generation of ROI (reactive oxygen intermediates) and RNI (reactive nitrogen intermediates), leading to enhanced antimicrobial function. On the other hand, chronic exposure to cocaine impaired the oxygen-dependent microbicidal capacity of macrophages, possibly through impaired expression of enzymes responsible for ROI and RNI formation. Proinflammatory cytokines may play a key role in cocaine-mediated immunosuppression, since exposure of macrophages to cocaine impairs the ability of the cells to produce these cytokines.