Varicella vaccine candidate demonstrates 87% efficacy

A varicella-zoster virus vaccine developed by Sinovac Biotech Ltd. has demonstrated 87.1% efficacy in children against chickenpox caused by the virus in a phase 3 clinical trial, according to a press release issued by the company.

“We are pleased to report an 87% efficacy rate from the phase 3 trial of our varicella vaccine,” Weidong Yin, chairman, president and CEO of Sinovac said in a press release. “The conclusion of this trial means that we are on track for commercialization by the end of 2019 and marks an important milestone in our goal to commercialize the varicella vaccine.”

The preliminary data released were collected from a double-blind, randomized, placebo controlled clinical trial conducted across the Henan province in China in August 2016 — before the epidemic season. Nearly 6,000 healthy children included in the study were given one dose of the vaccine, and all were aged between 1 and 12 years.

A second clinical study for the varicella vaccine was also conducted in which the consistency of the of the vaccine was assessed. The clinical study included 1,197 volunteers and three consecutive lots of the vaccine. Children aged between 1 and 3 years received the vaccine and were assessed after 30 days. Antibody geometric mean titers (GMTs) were observed to be consistent (95% CI, 0.67-1.5). There was also a safe and consistent immune response in all groups.

“Once commercialized, the varicella vaccine will be supplied to meet existing market demand and support our subsidiary Sinovac Dalian in strengthening its financial position in the near future,” Yin said in the release.

Clinical research approval for the varicella vaccine candidate was obtained by Sinovac in September 2015. Phase 1 trials were completed in 2016, and preliminary results of these trials backed the safety profile of the vaccine. – by Katherine Bortz