CanSino Biologics Steps into the Spotlight

China-based CanSino Biologics reports it is poised to file for emergency use authorization of its single-dose COVID-19 vaccine candidate in Mexico, Russia, and several other countries, pending final analysis of its Phase 3 clinical trial. The data will be available “in the coming days,” according to Xuefeng Yu, PhD, co-founder and chairman of CanSino Biologics, who offered an update on the company’s efforts at a symposium hosted by the New York Academy of Sciences, The Quest for a COVID-19 Vaccine.

In addition to short-term efficacy data, CanSino’s results will ultimately provide the first measures of the durability of the protection conferred by a COVID-19 vaccine. The trial, which spans 70 sites and 40,000 participants in Argentina, Chile, Mexico, Pakistan, and Russia, includes a cohort of participants who are being tracked for a full year following vaccination. To date, CanSino is the only vaccine developer with a trial spanning that length of time. Those results are expected in the Fall.

Interim analyses have shown that CanSino’s vaccine is well tolerated across age groups, with no reports of serious adverse events. Outside of the trials, more than 150,000 members of the Chinese military have already received the vaccine under an emergency use agreement. Yu reported no adverse events in these populations, while acknowledging that efficacy is difficult to assess in China, “where there are really no cases right now.”

Experts have touted the desirability of a single-dose vaccine at a time when manufacturing capacity is scarce and infection rates are soaring.  Yu commented that “if a single-dose regimen gives good protection, that will slow down and potentially even stop the pandemic,” adding that “this vaccine could certainly be boosted at a later time.” CanSino’s Ebola vaccine trials, which utilized a similar viral vector platform in a one-dose regime, indicated a “tenfold increase” in antibody level following a six-month booster.

CanSino is also testing a two-dose regimen in China, a trial that is likely to be among the first in the world to provide safety and efficacy data on a COVID-19 vaccine in young children. Yu explained that the two-dose trial, which began in September, includes participants as young as six years old.

New COVID-19 variants have emerged around the globe, sparking concerns about vaccine efficacy. Yu confirmed that all positive cases among participants in the five countries involved in CanSino’s trial will be sequenced to monitor the vaccine’s performance against variants circulating in those regions, although that process is still in the early stages.

Yu is optimistic that the “truly international collaboration” between CanSino and its partners will successfully bring a vaccine to market this year. “We’re a new company, and our facility is under construction,” Yu said, estimating that his team will produce 200-300 million doses of vaccine in 2021. Globally, the initial phase of vaccination will be a multi-year effort, and experts anticipate that periodic COVID-19 booster shots will be necessary. To meet future demand, CanSino is planning to open a second manufacturing facility to deliver between 600 million and 1 billion doses annually in 2022 and beyond.