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Biomedical subjects

Bruce Smith

Publications and source records attributed to Bruce Smith.

7 recordsLinked to original sources

A pilot study to quantify parental anxiety associated with enrollment of an infant or toddler in a phase III vaccine trial.

We sought to measure the anxiety felt by parents at the time of entry into a randomized controlled vaccine trial, and to determine if anxiety level was associated with parental demographic variables or past experience. The children were 2-month-old infants entering a randomized controlled clinical trial (RCT) of a diphtheria-tetanus toxoid-acellular pertussis vaccine adsorbed with Haemophilus influenzae B conjugate, or toddlers enrolling in a RCT of a Meningococcal C conjugate vaccine. Nurses interviewed parents to collect demographic data and parents self-administered the Spielberger Self-evaluation Questionnaire (State Anxiety STAI-Y-I) [Manual for the State-Trait Anxiety Inventory (Form Y) (Self-evaluation Questionnaire), Consulting Psychologists Press Inc., Palo Alto, 1983], a validated instrument measuring the temporary condition of "state anxiety." A regression tree (CART) (S-Plus) was used to identify factors associated with higher anxiety scores. Parents of 97 children enrolled. Anxiety scores ranged from 22.75 (lower anxiety) to 36.43 (higher anxiety). The regression tree identified a structured tree with six branches. The highest anxiety scores occurred in fathers with education less then grade 8, mothers with education less than high school, birth order of the child less then the third, previous serious illness in the family, or lack of experience with research. In a group of parents agreeing to enroll their infant or toddler in a vaccine study, certain attributes and experiences were associated with higher anxiety at the time of immunization in the context of a RCT. These factors should be considered by vaccine researchers in the recruitment process of clinical trials.

Adult↗

Safety and immunoenhancing effect of a Chlorella-derived dietary supplement in healthy adults undergoing influenza vaccination: randomized, double-blind, placebo-controlled trial.

BACKGROUND: Enhancement of immune function has been claimed as a benefit of some natural health products, although few have been subjected to randomized clinical trials. We evaluated the effect of an oral dietary supplement derived from the edible microalga Chlorella pyrenoidosa on immune response after influenza vaccination. METHODS: We conducted a randomized, double-blind, placebo-controlled community-based clinical trial in a convenience sample of 124 healthy adults at least 50 years of age randomly assigned to receive the study product (200 or 400 mg of a Chlorella-derived dietary supplement) or placebo. Participants took the study product or placebo once daily for 28 days. On day 21, we administered a single dose of a licensed trivalent, inactivated influenza vaccine. We obtained serum specimens to measure hemagglutination inhibition titres before and 7 and 21 days after vaccination. The primary immunological outcomes were the proportion of participants with a 4-fold or greater increase in antibodies and geometric mean antibody titres after vaccination; the proportion of participants reporting adverse events during therapy was the safety outcome. RESULTS: A total of 117 (94%) participants completed all aspects of the study. There were no differences in the proportions of recipients of 200 or 400 mg of the Chlorella-derived dietary supplement or placebo who achieved at least a 4-fold increase in antibodies (proportions for the 3 virus strains ranged from 17.9% to 28.2% for the 200-mg group, from 11.1% to 22.2% for the 400-mg group and from 19.0% to 21.4% for the placebo group; p > 0.05 for all comparisons). Reports of adverse events were similar for recipients of the supplement and placebo, except with regard to fatigue, which was reported more frequently by recipients of 200 mg of the supplement (18/41 or 44%) than by those who received 400 mg of the supplement (8/40 or 20%; p = 0.032) or placebo (8/42 or 19%; p = 0.019). Recipients of 400 mg of the supplement who were 55 years of age or younger had significantly higher geometric mean antibody titres against influenza A/New Caledonia 21 days after vaccination (p = 0.047) and against B/Yamanashi 7 days after vaccination (p = 0.034); the trends were nonsignificant for titres against A/Panama. We also observed similar increases for the proportions of subjects with a 2-fold or greater or a 4-fold or greater increase in antibodies. INTERPRETATION: The Chlorella-derived dietary supplement did not have any effect in increasing the antibody response to influenza vaccine in the overall study population, although there was an increase in antibody response among participants aged 50-55 years. Adverse events were similar among those receiving the supplement and the placebo. Further studies are warranted to explore the range of clinical effects resulting from ingestion of this dietary supplement.

Adjuvants, Immunologic↗

A phase I study of the safety and immunogenicity of recombinant hepatitis B surface antigen co-administered with an immunostimulatory phosphorothioate oligonucleotide adjuvant.

Certain oligodeoxynuclotides with CpG motifs provide enhanced immune response to co-delivered antigens. We performed a phase I, observer-blinded, randomized study in healthy anti-hepatitis B surface antigen (anti-HBsAg) antibody negative adults to explore safety and immunogenicity of co-injection of recombinant HBsAg combined with an immunostimulatory DNA sequence (ISS) 1018 ISS. Four ISS dosage groups (N=12 per group) were used: 300, 650, 1000 or 3000 microg. For each group, two controls received 20 microg HBsAg alone, two controls received ISS alone, and eight subjects received ISS+20 microg HBsAg. Subjects received two doses 8 weeks apart. Injection site reactions (tenderness and pain on limb movement) were more frequent at higher ISS+HBsAg doses but were mainly mild and of short duration. Higher anti-HBsAg antibody levels were associated with higher ISS doses. Four weeks after the first dose, a seroprotective titer (>or=10 mIU/ml) was noted for 0, 25, 75, and 87.5% of subjects by increasing ISS dose group (P<0.05) for those who received ISS+HBsAg; 1 month after the second dose this increased to 62.5, 100, 100, and 100%, respectively. Geometric mean anti-HBsAg antibody levels by increasing ISS+HBsAg dose were 1.22, 5.78, 24.75, and 206.5 mIU/ml after the first dose and 65.37, 877.6, 1545, and 3045 mIU/ml after the second dose. We conclude that 1018 ISS+HBsAg was well tolerated and immunogenic in this phase I study in healthy adults and may offer the potential for enhancement of hepatitis B virus (HBV) immunization and protection after one or two doses or in individuals who fail to respond to the standard vaccine regimen.

Adjuvants, Immunologic↗

Nature, evolution, and appraisal of adverse events and antibody response associated with the fifth consecutive dose of a five-component acellular pertussis-based combination vaccine.

We performed a randomized, controlled clinical trial to characterize the evolution of the adverse events associated with the fifth consecutive dose of an acellular pertussis vaccine, and to assess the level of discomfort associated with the injection and the attitude of parents concerning these events. A total of 505 children who had received either four doses of acellular pertussis vaccine or whole-cell pertussis vaccine were given a fifth dose of one of the two vaccines. Adverse events were monitored by parents and collected by telephone or home visit at 4, 8, 12, 24, 48 and 72 h, and 7 and 28 days after immunization. Rates of injection site redness >or=50mm were similar in recipients of five doses of acellular pertussis vaccine (32.8%) or five doses of whole-cell pertussis vaccine (43.3%). Injection site swelling, tenderness, and decreased arm movement were all more frequent in children who received five doses of whole-cell pertussis vaccine. Antibody levels before or after immunization did not predict those children who had increased injection site reactions. The children rated the injection site reactions as significantly more severe after five consecutive doses of whole-cell vaccine. Parent satisfaction was higher after the acellular vaccine. We conclude that a fifth consecutive dose of a whole-cell pertussis vaccine is associated with high rates of tender redness and swelling at the injection site, in contrast to a fifth consecutive dose of an acellular pertussis vaccine which is associated with high rates of non-painful redness. However, parents will still need to be aware of the high rates of injection site reactions expected after a fifth dose of acellular pertussis vaccine.

Child↗

Safety and immunogenicity of a trivalent, inactivated, mammalian cell culture-derived influenza vaccine in healthy adults, seniors, and children.

We performed randomized, double-blind, controlled trials to assess the safety and immunogenicity of an inactivated, Madin Darby Canine Kidney (MDCK)-derived cell line produced influenza vaccine in healthy adults (19-50 years), children (3-12 years) and the elderly (> or =65 years). We studied three lots of cell culture-derived vaccine and one lot of licensed egg-derived vaccine in healthy adults (n=462), two lots of cell culture-derived vaccine and one lot of egg-derived vaccine in seniors (n=269), and one lot of each vaccine in children (n=209). Adverse events were collected during the first 3 days post-immunization; serum was collected before and 1 month after immunization. Rates of local and systemic adverse reactions were similar with both vaccines. An injection site adverse event rated at least moderate severity was reported by 21.9% of children who received the egg-derived vaccine and 25.0% of those who received the cell culture-derived vaccine. In healthy adults the proportions were 12.1 and 15.3%, respectively and 6.7 and 6.3%, respectively in seniors. Systemic events of at least moderate severity were 12.4 and 12.5% in children, 19.8 and 13.6% in healthy adults, and 14.1 and 9.7% in seniors; none of these differences were statistically significant. The antibody response against all three viruses was similar between the two vaccines. From 83 to 100% of children, healthy adults and seniors achieved hemagglutination inhibition titers in excess of 40 post-immunization. We conclude that the cell culture-derived vaccine was safe and immunogenic in children, healthy adults and seniors.

Adolescent↗

Use of lidocaine-prilocaine patch to decrease intramuscular injection pain does not adversely affect the antibody response to diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b conjugate and hepatitis B vaccines in infants from birth to six months of age.

BACKGROUND: Topical lidocaine-prilocaine (EMLA) effectively decreases the pain associated with minor procedures including immunization, although the effect on the antibody response to diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b conjugate (DTaP-IPV-Hib) and hepatitis B vaccines has not been assessed. OBJECTIVE: To measure the antibody response to DTaP-IPV-Hib and hepatitis B vaccines; to measure pain reduction associated with the use of the lidocaine-prilocaine (EMLA) patch; and to assess safety by comparing adverse reactions. PARTICIPANTS AND SETTING: One hundred nine healthy 6-month-old infants (Part A of study) and 56 healthy infants birth to 2 months of age (Part B of study) undergoing primary immunization with DTaP-IPV-Hib and hepatitis B vaccines in an ambulatory setting. DESIGN AND INTERVENTIONS: Two center, randomized, double blind, controlled trial of EMLA patch or placebo before DTaP-IPV-Hib and hepatitis B immunization. Antibody titers measured at 0 to 2, 6 and 7 months. OUTCOME MEASURES: The primary outcome measure was the antibody response to diphtheria, tetanus, pertussis antigens, Haemophilus influenzae type b and hepatitis B by enzyme immunoassay; and poliovirus 1, 2 and 3 by neutralization. The secondary outcomes were pain scores by the Modified Behavioral Pain Scale and drug- and vaccine-associated adverse events collected with a parent diary and structured questionnaire. RESULTS: There was no difference in the antibody response between the EMLA- and placebo-treated groups as assessed by geometric mean antibody titers, rates of seroconversion or the proportion of participants achieving protective or positive antibody titers postimmunization. At the 6-month visit, EMLA recipients had less pain after immunization (total pain score, 6.75 vs. 7.35; P = 0.005; pain score increase, 3.99 vs. 4.74; P = 0.004) than did placebo recipients. Skin pallor and erythema at the patch application site were more frequently reported after EMLA use. Rates of vaccine-associated adverse events were similar in the two groups. CONCLUSIONS: The EMLA patch has no adverse effect on the antibody response to the vaccine antigens, is effective in reducing pain associated with DTaP-IPV-Hib and hepatitis B immunizations and does not result in any significant or unexpected adverse reactions.

Administration, Topical↗

Simultaneous administration of meningococcal C conjugate vaccine and diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b conjugate vaccine in children: a randomized double-blind study.

BACKGROUND: Meningococcal C disease can be life-threatening in infants, young children and adolescents. New conjugate vaccines are immunogenic in young infants and induce immunologic memory, so we should consider incorporating them into the routine childhood immunization program. The objective of this study was to measure the safety and immunogenicity of a meningococcal C conjugate vaccine when given with routine childhood vaccines. METHODS: We carried out a randomized, double-blind, controlled clinical trial at children's hospitals in 3 Canadian cities. A convenience sample of 351 healthy 2-month-old infants was enrolled from the community and randomly allocated to receive either meningococcal C conjugate vaccine or the control (hepatitis B) vaccine. All participants received a concurrent injection of the combined diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b (DTaP-IPV-Hib) conjugate vaccine in the opposite limb. Participants were immunized at 2, 4, 6 and 15 months of age; adverse events were recorded after each dose. Serum bactericidal and ELISA meningococcal antibody levels in the participants were measured at 6, 7, 15 and 16 months of age; diphtheria, tetanus, H. influenzae type b, poliovirus and pertussis antibodies were measured at 7 months of age. A total of 323 (92%) participants completed all aspects of the study. The proportion of participants who suffered adverse events after each vaccine dose was the primary safety outcome. Geometric mean antibody titres and the proportion of participants with protective antibody levels after immunization were the primary immunologic outcomes. RESULTS: After 2 doses of the meningococcal C conjugate vaccine 99% of participants achieved a protective ( > or = 1:8) bactericidal meningococcal serogroup C antibody level, and after 3 doses this rate increased to 100%. Antibody levels to the concomitant vaccine antigens in the group receiving meningococcal C vaccine were similar to those in the control group except for higher antidiphtheria antibody titres (p < 0.001). Local injection site reactions (redness and induration) after the meningococcal conjugate vaccine were more frequent than after hepatitis B vaccine but less frequent than after the DTaP-IPV-Hib vaccine. CONCLUSIONS: The meningococcal C conjugate vaccine can be safely and effectively administered at the same visit as the other vaccine antigens routinely given to infants in Canada.

Antibody Formation↗