A Swedish governmental Medical Evaluation Agency (SBU) has recommended in a recent report that the National Board of Health and Welfare review its strategy of prevention of cervical cancer. The widespread use of human papilloma virus vaccines, promoted by the manufacturers in a public advertising campaign, is about to add costs to an already strained cancer prevention budget while the effectiveness of vaccinations cannot be evaluated for two or three decades, the daily paper Dagens Nyheter reports.
Headlined “Hyped cancer vaccine betrays womens' health”, the article says that advertising built public pressure to add Gardasil to the child vaccination schedule and has built up exaggerated hopes that cannot be confirmed by an analysis of the scientific data.
SBU, the Swedish Council on Technology Assessment in Health Care, is very much an "establishment" governmental agency doing cost benefit evaluations of therapies based strictly on Evidence Based Medicine.
- - -
“Hyped cancer vaccine betrays womens' health”
New expert study today about protection against cervical cancer
Misleading marketing of a new cancer vaccine is an incredible betrayal against Swedish women and risks to create new health risks. High expectations have been linked to two new vaccines against certain types of virus that can cause cervical cancer. There is much pressure on the National Board of Health and Welfare to incorporate these vaccines in the general child vaccination program. But an expert study that was presented today shows that the knowledge is insufficient and uncertain in order to draw conclusions about the vaccines' preventive effect against cancer. A serious risk with general vaccination is that fewer women will receive gynaecological cell sample controls which leads to new health risks. And misleading publicity for the vaccine drives up the expectations in a way that constitutes an incredible betrayal against the women, writes Nina Rehnqvist, along with Rosén and Susanne Vilhelmsdotter Allander, director and project managers on the State's board for medical evaluation, SBU.
Sweden has come far in the struggle against cervical cancer. Since regular gynaecological cell sample controls were introduced at the end of the 1960s, the number of new cases of established cancer have been more than halved. Despite this 450 women each year get cervical cancer and 150 die of the disease.
Therefore, it is good to see that research in this area has shown much progress in these last years. It has so far resulted in two vaccines against infections of certain types of humane papilloma virus (HPV), which in some cases causes cell changes that may over time develop into cervical cancer in some women. Increased knowledge about HPV may also be used in the investigation and follow-up of abnormal gynaecological cell samples.
The debate about the new vaccines, Gardasil and Cervarix, is extensive and there is much pressure on the National Board of Health and Welfare to add vaccination against HPV 16 and 18 to the general child vaccination program. Before such a decision, a thorough review of the scientific knowledge is required. Today, the State's board for medical evaluation (SBU) presents a report that systematically checks the research results for the two vaccines.
To start, it is important to clarify that we are not dealing with vaccines against cervical cancer. They are vaccines against two types of HPV-infection, out of more than 13 HPV-types that are associated with cervical cancer. These HPV-infections resolve by themselves in most cases, but can in certain case become permanent and cause cell changes. in some women, the cell changes may develop over time into cancer.
The reason that researchers targeted just these two HPV-types is that in several countries their presence can be demonstrated in up to two thirds of women fallen ill with cervical cancer. The average infection rate varies in different countries. Nordic studies have shown that the proportion of cervical cancers that can be influenced by a general vaccination against HPV 16 and 18 is lower.
SBU finds that at present it is not possible to say to what extent a general vaccination of children against the two HPV-types can prevent future cancer cases. There are some scientific indications that vaccines can prevent cell changes due to HPV 16 and 18, but the effect on cancer is noticed only after several decades. The follow-up studies that have been done so far are naturally too short to allow us to draw any conclusion about cancer. A calculation shows that it may be possible to prevent approximately half of the cases of cervical cancer with a general vaccination of children against HPV 16 and 18.
Another important uncertainty is that nobody today knows how a general vaccination of children against HPV 16 and 18 could in the long run influence the participation of vaccinated women in gynaecological cell sample controls. Already today, few women participate in those controls and only five county councils reach the EU's and WHO's objectives to test 85 per cent of all women. In Sweden, the national average is 78 per cent, according to the national quality register for gynaecological cell sample control. In certain county councils only 60 percent participate.
There is a risk that exaggerated expectations about the effectiveness of a general vaccination can create a situation where fewer women in the future participate in the cell sample controls, and thereby may cause new health risks. The existing vaccines cannot replace the cell sample controls, but must instead be seen as a possible complement.
It is not established for how long the HPV-protective effect lasts and whether one or more refresher doses will be needed for life-long protection. Also here, a knowledge gap exists: it is not possible today to decide with the help of a blood sample how long the protection will last. It is unclear which level of antibodies signifies protection from infection. Possible long-term secondary effects are not known either. Medicine agencies around the world are monitoring the reported side effects.
Another uncertainty is cost effectiveness. The direct costs are about 200 million Swedish Kronor for each production batch, by the time the vaccinations of girls are complete, and it is expected that effects will only be noticeable after 20-30 years. Each refresher dose costs additional 60 million Swedish Kronor. If boys are to be vaccinated as potential infection carriers the cost is doubled. Added too this are costs for a careful follow-up of everyone vaccinated during several decades. All these costs are in addition to the immediate costs, since at least during the vaccination follow-up time the costs for cell sample control and other preventive measures continue.
The cost for a general child vaccination program must be evaluated against an alternative use of resources. The question that must be answered is whether the money would do more good if it were invested in other preventive measures and in treatment of cancer or other diseases. Perhaps the State and the county councils can negotiate a lower price so that a general vaccination program might be a cost effective preventive method.
Last summer, the producer of Gardasil set in motion a massive marketing campaign that was unique in that it targeted the general public directly in the form of big ads in newspapers and radio commercials. Marketing to the general public is not permitted for prescription drugs, but there is an exception for vaccines. It is still unclear how the exception will be interpreted. It is entirely clear however, that the campaign promoting protection against HPV 16 and 18 and protection against cancer has contributed to raise people's expectations and increase demand for the vaccines.
According to an opinion survey, many women believed that the advertising campaign was initiated by the government and that the vaccine would protect against cervical cancer.This is a clear indication that advertising must be balanced with neutral information that is independent of the vaccine producers. Anything else is an incredible betrayal of Swedish women.
The pressure from public opinion is now influencing political decision makers. County councils that stand to pay for the costs in addition to the cost of normal protective measures have in several cases wanted to lower the number of individual vaccinations waiting for a decision from the National Board of Health and Welfare. This has in turn created a debate around inequality within the healthcare system depending on one's home town. The question about vaccination against HPV-infections is now high on the political agenda, among other thing in the form of several legislative initiatives from members of the
Swedish parlament during the autumn.
The purpose of the SBU is to provide a systematic evaluation of medical methods and not to take a position whether vaccination against HPV 16 and 18 should be added to the general child vaccination program or not.
We have been requested to check the available information pending the National Board of Health and Welfare's decisions and have found significant knowledge gaps that make it difficult to assess the effect of a general child vaccination program on future incidence and mortality in cervical cancer.
We are in agreement that prevention of cervical cancer is important. Women's lives are at stake. The new vaccines are a very positive step but cannot single-handedly solve the problem of cervical cancer, although they probably can prevent some cases. We consider that a review of the entire preventive strategy is in order.
|
|
