The Lyme Vaccine That Got Away – article or 27 minute podcast
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Dennis Brasky
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hari kumar
Hello Dennis: Not at all gainsaying the role of profits in withdrawing of that vaccine - about which I knew/know very little to be honest. However I do not think it is quite an open and shut case - I think anyway. Paul Offit's views in general on vaccines are very reasonable, but not his 'exemptions for industry' [If I can put it like that] conclusions, as the article indicates that he would likely state in response to query.
In any case re Lyme: From: The Lyme disease vaccine--a public health perspective.
"An ideal vaccine must be able to induce a high and sustained duration of protection, preferably for a number of years and with the fewest number of booster doses possible (ideally, with no booster doses). LYMErix lacks some of these ideal charac- teristics owing to its unusual mode of action as a ‘‘transmission blocking’’ vaccine. Because the vaccine-induced protective re- sponse occurs in the nymph or adult tick vector when it feeds and before the causative spirochete enters the human host, the vaccine must produce high levels of circulating antibody to ensure protection against infection at the time of a tick bite [19]. ‘‘Breakthrough’’ infections cannot be cleared by host antibodies or trigger an anamnestic response, because B. burgdorferi no longer synthesize OspA at the time of entry into skin. Therefore, although OspA-based vaccines have been shown to be effective, it is unlikely that adequately protective titers can be achieved and maintained without multiple booster vaccinations. If fewer booster doses are important for the success of an ideal Lyme disease vaccine, antigens other than OspA may need to be identified.
A second concern about a new candidate Lyme disease vac- cine relates to the necessity for the vaccine to be approved for use in the highest-risk groups. As mentioned above, one of the limitations of LYMErix was that, at the time of licensing, it had not yet been approved for use in children ,15 years of age. Consequently, the vaccine was not available for one of the groups at highest risk for contracting Lyme disease, children 5–14 years of age. It is imperative that a second-generation Lyme disease vaccine is demonstrated to be safe and effective in this target population. A third concern for a new Lyme disease vaccine has to do with the potential false sense of security that could result in vacci- nated individuals who neglect to consider that the ticks that transmit Lyme disease transmit a number of other pathogens, as well. ........ Two additional considerations in the development of a future Lyme disease vaccine are important to recognize. First, sales for a vaccine will most likely be geographically limited to the Northeastern and Midwestern regions of the United States, because Lyme disease risk is largely regional. Second, Lyme disease, when accurately diagnosed, is generally treatable with antimicrobials." |
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