The Chinese vaccine industry has been criticized in recent years for selling substandard, expired and improperly stored pediatric vaccines. Investigations into some of the quality failings have uncovered evidence of data fabrication and improper relationships between businesses and regulators.
China moved to restore confidence in vaccines and prevent additional scandals last year by putting in place new, tougher rules covering the whole product life cycle. Under the new rules, teams of national and local inspectors specialized in vaccines will oversee the development, production and distribution of vaccines in China.
Late last month, Sinovac became the first company to win approval for a vaccine under the revised regulatory regime. The Chinese National Medical Products Administration approval covered a vaccine to protect children aged one to 12 years old from the varicella-zoster virus, which causes chickenpox.
Sinovac’s CEO, Weidong Yin, talked up the positive implications of his company’s ability to get a vaccine approved in the new regulatory environment.
Yin said, “Our ability to continue to gain approval for our products since the government issued the Vaccine Management Law and implemented stringent management of the vaccine industry is a testament to the strength of our operations and the quality of our products.”
Sinovac was implicated in some of the cases that led China to rethink its approach to vaccines. In 2016, a former deputy director of China’s Center for Drug Evaluation was found guilty of accepting bribes from Sinovac and other Chinese vaccine manufacturers.
Having navigated the new regulatory regime to get a vaccine to market in China, Sinovac is interested in expanding beyond its home territory. Yin noted that around 40 countries include vaccines against varicella in government-sponsored immunization programs, providing Sinovac with multiple other sources of potential revenue.
In the US, Merck’s Varivax is the only single indication varicella vaccine approved by the Food and Drug Administration (FDA). Merck also sells a combined measles, mumps, rubella and varicella virus vaccine, branded ProQuad, in the US.
A trial of an older formulation of Varivax found no subjects who received the vaccine contracted varicella in the first year after immunization, compared to 8.5% of participants in the control arm.
Sinovac won Chinese approval for its varicella vaccine after running a clinical trial in which 0.2% of people who received the product contracted the virus – more than 1.5% of participants in the control group contracted varicella.