A new vaccine research project, funded by the 6th EU Research Framework Program, has been launched recently. The project will last for 3 years and involves four industrial and five academic institutions from six European countries.
The project, called ‘Assessment of structural requirements in complement-mediated bactericidal events: towards a global approach to the selection of new vaccine candidates’, or BacAbs for short, aims to find novel vaccine candidates that can trigger immune responses (antibodies) with bactericidal activities.
Using high-throughput molecular biology techniques as well as bioinformatics the BacAbs project will screen and analyze DNA and protein sequences of the model bacterium, Neisseria meningitidis serogroup B, which causes septicemia and meningitis and for which there is no vaccine available.
Candidate proteins are predicted to be bacterial surface proteins or their fragments, which can elicit antibodies that assist the complement system of the body’s innate immunity to recognize and kill targeted bacteria. Candidates will be identified structurally using bioinformatics and subjected to various experimental assays.
The project’s consortium includes an experienced industrial partner in vaccine research, Novartis Vaccines and Diagnostics (Italy), and three other small enterprises in Latvia, France and Spain, which hold several key technologies. Academic partners are outstanding universities from Italy, Spain, Germany and The Netherlands. The project is coordinated by Xavier Daura of the Institute of Biotechnology and Biomedicine (Autonomous University of Barcelona, Spain).
Source: The Autonomous University of Barcelona, Spain (www.uab.es).
Extremely preterm infants do respond to vaccines
It had been an assumption that pediatric vaccines, such as the measles–mumps–rubella (MMR) and chicken pox vaccines, can work effectively in preterm infants despite their apparently unmatured immune systems. Recent findings published in the March issue of Pediatrics have confirmed this assumption.
“The assumption has always been that it would be OK, that very early babies would have enough immunity, but no one had formally researched the subject”, said Carl D’Angio of the University of Rochester Medical Center (NY, USA) and first author of the study. “I’m happy to be able to reassure my colleagues and parents that it is OK.”
The study involved 16 full-term and 16 extremely preterm (born within 6.5 months of pregnancy) infants. D’Angio and colleagues found that both groups of infants responded equally well to the MMR and chicken poxvaccines.
Before the vaccines became available, measles, mumps, rubella and chicken pox were very common in children and could result in serious complications, leading to disability or even death. The vaccines have significantly reduced this burden in the pediatric population and the new findings confirm the efficacy of these vaccines in extremely preterm infants.
The study is the first of its kind investigating immune responses to vaccines in extremely preterm infants. A similar study on a pneumococcal conjugate vaccine is being completed by the same research group.
Sources: The University of Rochester Medical Center, NY, USA (www.urmc.rochester.edu).
D’Angio CT, Boohene PA, Mowrer A et al. Measles–mumps–rubella and varicella vaccine responses in extremely preterm infants. Pediatrics 119(3), e574–e579 (2007).
Debate over MMR vaccine and autism heats up
Do mercury-containing vaccines, such as the MMR vaccine, lead to an increase in autism incidence, such as pervasive developmental disorder (PDD)? The majority of scientific evidence suggests that such a link does not exist. However, this debate was revisited at the National Autism Association (NAA, MO, USA) meeting in March 2007 after a recent publication on this subject appeared in the July 2006 issue of Pediatrics.
The Pediatrics paper by Eric Fombonne and colleagues at the Montreal’s Children Hospital (QC, Canada) reported an increase in PDD rates despite the decreased coverage of MMR vaccines. The authors concluded that “the findings rulled out an association between PDD and either high levels of ethylmercury exposure … or one- or two-dose MMR vaccinations”.
However, at the March 2007 NAA meeting, David Ayoub presented new findings suggesting a correlation between mercury-containing vaccines and rates of PDD. Ayoub and his colleagues monitored five Montreal schools compared with only one in Fombonne’s study and found that the peak rate (one in 87 children) of PDD correlated with an increase in coverage of mercury-containing vaccines. They also found that this rate was now flattening as the vaccines were withdrawn slowly.
“This new information confirms a relationship between vaccines and autism that cannot be explained by better diagnosing or changing diagnostic criteria”, said Karen McDonough, NAA-Chicago president.
The new findings also pointed out several errors in Fombonne’s study. Subsequently, Ayoub and his colleagues wrote a letter to Pediatrics, which was then refused for publication. “I believe the evidence of no link between MMR and autism is sufficient. It’s not worth publishing more on this subject”, said Pediatrics editor JeroldLucey.
“This dismissal of legitimate concerns regarding data affecting those suffering with autism is a disgrace”, commented McDonough.
Sources: The National Autism Association, MO, USA (www.nationalautism.org).
Fombonne E, Zakarian R, Bennett A, Meng L, McLean-Heywood D. Pervasive developmental disorders in Montreal, Quebec, Canada: prevalence and links with immunizations. Pediatrics 118(1), e139–e150 (2006).
Safety updates on rotavirus vaccine
The US FDA has updated the safety profile of Rotateq®, a vaccine against rotaviral gastroenteritis by Merck & Co. (NJ, USA). Compared with placebo, the vaccine did not result in increased incidence of intussusception (intestinal blockage due to the bowel folding in on itself) or hematochezia (bloody stools).
Rotavirus is the most common cause of severe diarrhea in infants and children, resulting in over 600,000 deaths worldwide every year. Rotateq was licensed in the USA in February 2006 to protect infants and children from rotavirus serotypes G1–4. More than 3.5 million doses of the vaccine have been distributed since then.
Intussusception occurs naturally in small children at a rate of 1:2000. The Rotavirus Efficacy and Safety Trial (REST) involved 70,000 infants, half of whom received Rotateq and the other half received a placebo. No increase in adverse effects, including intussusception, was observed in the vaccine compared with the placebo group. The incidence of hematochezia, a serious adverse events, was reported as less than 0.1%, while other adverse events were bronchiolitis (0.6%), gastroenteritis (0.2%), pneumonia (0.2%), fever (0.1%) and urinary tract infection (0.1%).
The REST results have been forwarded onto the US Vaccine Adverse Events Reporting System (VAERS), a national surveillance program sponsored by the US FDA and CDC that collects data on any vaccine-related adverse incidence.
“It is common for postmarketing experience information with a vaccine to be reported to VAERS and for the prescribing information to be updated accordingly”, said Mark Feinberg, Merck’s Vice President of Policy, Public Health and Medical Affairs. “Merck places public health and patient safety as our highest priorities, and we are very confident in the data supporting the safety profile of Rotateq from the placebo-controlled REST. Merck will continue to work with the FDA and the CDC to monitor postmarketing experience with Rotateq by collecting data from additional systems, including active, controlled surveillance studies in addition to passive reporting systems, such as VAERS.”
Rotateq has been recommended by the US CDC’s Advisory Committee on Immunization Practices and the American Academy of Pediatrics.
Source: Merck & Co., Inc., NJ, USA (www.merck.com).
Third influenza vaccine for birds available
The European Medicines Agency’s Committee for Medicinal Products for Veterinary Use (CVMP) announced at its meeting on March 13–15 that it has recommended a third influenza vaccine be made available for birds. The vaccine, Nobilis Influenza H7N1, is an inactivated, adjuvanted, injectable vaccine and is manufactured by Intervet International BV.
The first influenza vaccine for poultry, also by Intervet, has been available in European countries since February 2006. Unlike the previous two vaccines using the H5 strains of the avian influenza virus, the new vaccine contains the H7 subtype. According to recent studies, both virus strains are highly pathogenic and can cause epidemics in bird populations, therefore vaccination against both strains is necessary despite the H5N1 strain being the main focus so far.
In clinical trials, the new vaccine reduced symptoms and mortality due to viral infection in chickens, as well as limiting viral secretion and transmission among chickens and ducks.
The new vaccine, together with the previous two, Nobilis Influenza H5N2 (Intervet International BV) and Poulvac FluFend H5N3 RG (Fort Dodge Animal Health BV), will be used in avian influenza control campaigns carried out by national competent authorities.
Source: The European Medicines Agency (emea.europa.eu).