Sinovac Biotech Ltd., a Chinese biopharmaceutical company, reported the preliminary results of its proprietary Inactivated Pandemic Influenza Vaccine (Human-used Avian Flu Vaccine) (Panflu) in phase I clinical trials. The project of R&D on Avian Flu Vaccine for human is sponsored and supported by Ministry of Science and Technology, and is co- developed by the Chinese Centers for Disease Control and Prevention (CDC) and Sinovac.
The preliminary results showed good immunogenicity, with a sero-positive rate of 78.3 per cent, which exceeds the criteria for assessment of vaccines established by Committee for Proprietary Medicinal Products of the European Union.
Sinovac CEO and chairman of the BOD, Yin Weidong commented, "This is another success for China's biotechnology industry and an encouraging event for us at Sinovac. Our R&D programmes have many proven successes and are the core of our business plan. It builds our organic product pipeline, enhances our marketing and sales programs, and creates synergy with our strategic partners."
The purpose of phase I was to provide an evaluation of vaccine's safety and immunogenicity and a reference for determining the vaccine dosage for phase II Clinical Trial. The Trial was conducted at the Beijing Sino-Japan Friendship Hospital in Beijing China, using a double-blind, randomized method of testing. Double-blind studies are designed to eliminate subjective bias on the part of both the experimental subjects and researchers. In a double-blind experiment, neither the subjects nor the researchers know who belongs to the control group or the experimental group.
For this clinical trial, 120 volunteers were divided into 4 groups of 30 persons each, of which 24 of were inoculated with the pandemic influenza vaccine and the other 6 with a placebo. Vaccine safety was documented through Blood Routing Tests, Blood Biochemistry Tests, Urine Routing Tests, and systemic observation of localized events. The preliminary result shows that Sinovac's vaccine is safe for humans; no serious adverse events occurred to any volunteers.
Once the phase I clinical trial is officially completed, Sinovac will start the application process with SFDA to approve commencement for the Phase II clinical trial. The Company will submit its summary report of Phase I Clinical trial, plan and protocol for Phase II Clinical trial and other relevant documents.
Sinovac's Panflu is a, inactivated whole virus vaccine with adjuvant. Four antigen dosages levels were tested in the Phase I clinical trial and all of them induced an immune response in the volunteers. The vaccine with 10ug antigen content demonstrated the best immunogenicity, with a sero-positive rate of 78.3 per cent, which exceeds the criteria for assessment of vaccines established by Committee for Proprietary Medicinal Products of the European Union.
The National Institute for Biological Standards and Control (NIBSC) provided Sinovac with a reassortant H5N1 virus strain to be used in the vaccine R&D process.
Signs of a possible pandemic flu have emerged in Southeast Asia, as lethal infections in poultry and humans, and infections of the H5N1 influenza virus strain continue to be reported. While there is no confirmed evidence of human-to-human transmission, there have been suspected cases identified in Indonesia in May 2005. It is feared that if the H5N1 influenza virus undergoes either a genetic alteration or recombination with a human influenza virus, a new subtype could emerge which could be both highly contagious and highly lethal in humans. Such a subtype could potentially cause a global influenza pandemic.
Most health officials estimate a flu pandemic could last a year or more, and millions of lives could be at risk. It is believed that one of the most effective countermeasures against pandemic flu is to manufacture mass quantities of vaccines as quickly as possible.