I apologize for ignoring this subject until now. Celvapan is the Baxter non-adjuvanted swine flu vaccine that is being used in many countries outside the US. It has no thimerosal. It is not grown in eggs, but instead is grown in tissue culture using Vero cells. This is a major advantage to people who have allergies to egg. But it is a new technique for influenza vaccines, one for which there is limited data. FDA is also concerned about the amount of residual Vero cell DNA in vaccines.
European regulators (EMEA) have approved new swine flu vaccines based on what they call “mock up vaccines.” What appears to have occurred is that new swine flu vaccines were approved on the basis of earlier trials of bird flu (H5N1) vaccines, which used the same adjuvants, or which used cell culture techniques. EMEA’s website (page dated April 29, 2009) discusses this subject. Per EMEA, both Celvapan and Pandemrix (GSK’s ASO3-adjuvanted swine flu vaccine, which does contain thimerosal) are listed as “mock-up vaccines” on the EMEA website, indicating that the names of older, bird flu vaccines that have undergone clinical trials were retained for the new H1N1 swine vaccines.
Here is how the process is described by Marie-Paul Kieny of WHO:
In the last couple of years, manufacturers in the European Union registered “mock-up” or prototype H5N1 bird flu vaccines as nobody knows which H5N1 strain might become a pandemic strain. Manufacturers made clinical batches of an H5N1 vaccine with virus stocks from China, Indonesia and Viet Nam. They carried out clinical trials and submitted the results to the regulatory authorities who said the vaccines were fine. They are not allowed to sell H5N1 vaccines, since there is no H5N1 pandemic, but they can use the same procedure to make H1N1 pandemic vaccine. That way they can get a licence in a few days. This is another way vaccines can be licensed without clinical trials, while still ensuring safety on the basis of what is known about influenza vaccines.
Because the clinical features of bird flu (50-70% mortality) are so different from swine flu, and the viruses are quite different, using clinical trial data from so-called “mock-up vaccines” designed for H5N1, to support approval of H1N1 vaccines, makes a mockery of the drug regulation process. Note that some or all unadjuvanted bird flu vaccines required 90 mcg antigen, and 2 doses, while unadjuvanted swine flu vaccines require only 15 mcg antigen and one dose. Although seasonal flu vaccines retain their names as strains change yearly, retaining the same names for both bird and swine vaccines engenders confusion as well.
Here, EMEA provides its pandemic influenza preparedness plan. Pent-up preparedness has demonstrated itself a force to be reckoned with.