The Children’s doctor
19 September 2009
Professor Adam Finn, from the Department of Cellular and Molecular Medicine, is an academic who prefers to say he is a paediatrician, because being a children’s doctor is what really defines him.
Finn is already used to operating like this because much of his work involves collaborating with dozens of people across large networks, some of which are spread around the world. His expertise is principally in the development of vaccines for children and much of this concerns clinical trials involving children, which is a relatively new field of investigation. Previously, people felt that they could not take risks with children by putting them in trials. This is, of course, a false argument because if trials do not involve children, the risks are taken in the clinic in an uncontrolled way, such that it is not always possible to detect when there is a problem. Now, however, the European Union requires companies licensing drugs to perform trials in children, unless there is no conceivable way in which a particular drug, such as an Alzheimer’s drug, would be used in children.
One particular study that Finn has recently contributed to is for a new pneumococcal vaccine. Pneumococcus is a bacterium that causes meningitis and pneumonia. Globally, pneumonia kills between one and two million children every year, so although we are all scared of meningitis, what we should really be concerned about is preventing pneumonia. Pneumococcus also causes ear infections, which, although they are not killers, lead to large numbers of antibiotics being prescribed for children. This, in turn, drives antibiotic resistance, as well as being a costly process. Thus the prevention of ear infections can also have a major impact on antibiotic resistance.
Globally, pneumonia kills between one and two million children every year
The picture is further complicated by the fact that there are 90 different types of pneumococcus bacteria, at least 20 of which cause disease in humans. Furthermore, as the vaccine is introduced and the disease caused by those strains disappears, new strains appear to fill the gap, so the vaccines have to be reformulated with more strains, just to keep pace. Since 2006, a pneumococcal vaccine containing seven different strains of the pneumococcus bacterium has been made available to all babies. However, a second vaccine with ten strains was licensed earlier this year, and a third, with 13 strains, is expected to be licensed at the end of this year – this latter study is the one Finn has been involved in. The uptake of this vaccine is very high – more than 90% – so it is having a very real impact.
Finn is also in the middle of a vaccine study against meningitis B, caused by a bacterium called meningococcus. Back in the 1990s, he was involved in a series of studies for a strain of meningococcus that caused meningitis C and this work led to the licensing of a vaccine that became part of the routine immunisation schedule in the UK from autumn 1999. As a consequence, in just ten years, we have seen the complete disappearance of meningitis C, which previously accounted for about 40% of meningitis cases. It has been a remarkable success – but meningitis B is still prevalent, so that is Finn’s current target. The Bristol group has just finished recruiting more than a hundred children to the study; other centres around the country are doing the same.
Since 2006, a pneumococcal vaccine containing seven different strains of the pneumococcus bacterium has been made available to all babies
A study Finn is just about to start is completely different from the others, in that it will be testing a live virus vaccine. It is designed to protect against two common viruses: RSV, or respiratory syncytial virus, and parainfluenza virus type 3, or PIV 3. Both viruses cause thousands of cases in babies every winter and hundreds of admissions to hospital of babies with breathing difficulties. The study is a particularly difficult one to do because the babies first have to have blood tests and then washes need to be taken from their noses to see how long the virus from the vaccine persists.
Another difficulty is that the virus has been genetically engineered and the words ‘genetic engineering’ strike fear into everybody’s hearts – not only those of parents, but also those of the regulators. In fact, it is only a cow parainfluenza virus that has had genes from the human RSV and parainfluenza viruses engineered into it. In the same way that the original smallpox vaccine came from cowpox and induced a very mild form of smallpox in the patient, the cow parainfluenza virus, which doesn’t make humans sick, should result in a mild, non-symptomatic infection that is able to induce immune responses to the human viruses and protect babies against them. This latest study will be conducted all over the world and Bristol is the leading centre in the UK, with Finn as the UK’s Chief Investigator. The first children are being recruited in Bristol as this article is being written. If it works, this vaccine has the potential to have an enormous impact on public health.
Finally, hot off the press, comes news that Finn and colleagues will be partners in a study to rapidly evaluate the antibody responses and side effects, in children aged six months to 12 years, of two new H1N1 swine ‘flu vaccines. The study is still subject to ethics and MHRA approval, but the team expects to start work by October 2009.