Oct 24, 2006 (CIDRAP News) – Swiss pharmaceutical maker Novartis claimed success last week in a phase 3 clinical trial of a seasonal influenza vaccine produced in cell culture rather than in eggs, the conventional production method.In a news release, the company said volunteers who received the vaccine had at least as strong an immune response as did volunteers immunized with an egg-based vaccine containing the same flu virus strains.The company, which presented preliminary findings at a flu vaccine conference in Vienna, said the safety profiles of the two vaccines were similar.Flu vaccines have been grown in chicken eggs since the 1950s. A number of companies are working on cell-based production, but no cell-based flu vaccine has yet been licensed. Novartis said it applied for European Union approval of its vaccine in June.”Novartis is committed to bring cell culture–derived influenza vaccine to market,” company CEO Jorg Reinhardt said in the news release. Cell culture is seen as a slightly faster and considerably more flexible production technology than the egg-based method.The Novartis vaccine is grown in canine kidney cells. Company officials said the product is a subunit vaccine, meaning it contains individual viral proteins rather than whole virus particles.In the phase 3 study, conducted in Poland in the 2004-05 flu season, 1,300 volunteers between the ages of 18 and 60 and 1,354 volunteers older than 60 were randomly assigned to receive the cell-based vaccine or an egg-based vaccine, Novartis reported. Each volunteer received one dose.Researchers found no difference in the immunogenicity of the two vaccines, both of which met all three immunogenicity criteria of the European Union’s Committee for Medicinal Products for Human Use, the news release said. Rates of local and systemic side effects were similar for the two vaccines in both age-groups.When asked how long it takes to produce the cell-based vaccine, company officials told CIDRAP News by e-mail, “Currently, basically the same as egg-based except lead times are much shorter and start-up is more flexible.”Officials said Novartis has completed phase 1 and 2 trials of the vaccine in the United States and will report the results in 2007. Currently the company is “in dialogue” with the Food and Drug Administration about the design of a phase 3 trial, they reported.