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.

Concomitant use of VAQTA with PedvaxHIB and Infanrix in 12 to 17 month old children

Open-label, multicenter, randomized study (NCT00289913) evaluated immunogenicity, safety, and tolerability of Vaqta (hepatitis A vaccine) administered with PedvaxHIB (Haemophilus b conjugate vaccine [Meningococcal protein conjugate]) & Infanrix (diphtheria/tetanus/acellular pertussis vaccine) in healthy, 15-month-old children. Five groups were evaluated: Group 1 received Vaqta/Infanrix PedvaxHIB on Day-1 and Vaqta at Week-24; Group 2 received Infanrix PedvaxHIB on Day-1, Vaqta at Week-4, and Vaqta at Week-28; Group 3 received Vaqta/PedvaxHIB on Day-1 and Vaqta Week-24; Group 4 received PedvaxHIB on Day-1, Vaqta at Week-4, and Vaqta at Week-28; and Group 5 (safety only) received Vaqta on Day-1 and Vaqta at Week-24. Hepatitis A seropositivity rate (SPR: ≥10 mIU/mL), Hib capsular polyribosylribitol phosphate (PRP) antibody response (>1.0 μg/mL), and geometric mean titers (GMT) to pertussis toxin (PT), pertussis filamentous hemagglutinin antibody (FHA), and pertactin were examined. Non-inferiority statistical criteria required a difference >10% in Hepatitis A SPR, PRP >1.0 μg/mL, and a GMT ratio of >0.67 for pertussis antigens. Injection-site and systemic adverse events (AEs) and daily temperatures were collected. Hepatitis A SPRs were 100% for Groups 1-4, regardless of initial serostatus. Anti-PRP titers were comparable (98.1% - 97.0%) for Groups 1-4. GMT and mean fold-rise were comparable for all 3 pertussis antigen components between concomitant and nonconcomitant groups. Criteria for non-inferiority of immune responses for concomitant vs nonconcomitant administration were met for Hepatitis A, Hib, and pertussis antigens. No statistically significant incidence differences of individual AEs were found between concomitant and nonconcomitant groups. No serious vaccine-related AEs or deaths were reported; no subject discontinued due to an AE. Immune responses to Vaqta, PedvaxHIB, and Infanrix given concomitantly were non-inferior to nonconcomitant responses. Vaqta administered with PedvaxHIB & Infanrix had an acceptable safety profile in 15-month-old children.

Telephone triage: results of adolescent clinic responses to a mock patient with pelvic pain

PURPOSE

The purpose of this study was to evaluate the appropriateness of telephone advice given by adolescent clinics.

METHODS

Using a mock scenario simulated by a teenage actress, adolescent clinics nationwide were telephoned by a 16-year-old female complaining of acute onset of "belly pain" in her left lower side. Upon questioning the mock patient, clinics were able to obtain further information. In short, it could be determined that the mock patient was sexually active, did not use contraception, was "late" for her period, and had just begun spotting. With the information available, a potentially life-threatening ectopic pregnancy could not be ruled out. Telephone triage of 35 clinics was evaluated according to the final disposition. Appropriate advice included arranging to see the patient that day or referring the patient to another facility (i.e., emergency department) to be seen that day.

RESULTS

Sixty-three percent of the clinics gave appropriate advice; 37% gave inappropriate advice. Nonprofessional personnel rendered the advice in over 60% of the calls.

CONCLUSION

This study suggests a need to reevaluate the procedures utilized to provide proper telephone advice to adolescents.

Haemophilus B polysaccharide vaccine. Antibody kinetics in 17- to 71-month-old children

The antibody response to polysaccharide vaccines is well known to be age variable, with younger infants or children responding less dependably and with lower antibody levels. The fate of these induced antibodies over time is less well understood. We studied the antibody kinetics of beta-Capsa 1, a Haemophilus B polysaccharide vaccine, in 185 children aged 17 to 71 months. Ninety percent of the children vaccinated at age 2 years or older achieved reportedly immune serum antibody levels three weeks after vaccination; 45% vaccinated at age 18 months achieved such levels. In six months, the antibody levels fell significantly in all children. In those vaccinated at age 18 months, the levels six months after vaccination were not significantly different from those prior to vaccination. Our study raises the possibility that antibody kinetics may be as critical a consideration as immediate antibody response in deciding the proper clinical use of a polysaccharide-based vaccine.