Sanofi and GlaxoSmithKline, two of the world’s biggest vaccine makers, began testing their experimental COVID-19 shot in the first patients on Thursday and aim to start late-stage trials before year-end.
The drugmakers started human studies at 11 sites across the U.S. The trial—which compresses the early and middle stages of clinical tests—will assess 440 healthy patients in two age groups: 18 to 49, and over 50. Sanofi and Glaxo aim to have results by December, allowing the final stage to begin.
Though the pair are just now starting human trials, a number of vaccine front-runners may deliver interim data from their late-stage studies as early as this month. There are more than 175 COVID-19 vaccines currently in development, according to the World Health Organization, and 33 in human trials. A handful have ambitions to secure emergency use authorizations in the fall.
“I’m not concerned that we’re a few months behind some of the other vaccine candidates,” John Shiver, senior vice president of global vaccine research and development, said in an interview. Sanofi’s expertise in conducting trials and “experience with very similar viruses” will allow it to gain back time on its peers, he said, and ultimately, multiple shots will be needed.
Sanofi shares rose 0.9% early Thursday in Paris, with Glaxo up 0.6% in London.
The vaccine candidate relies on technology Sanofi uses to make influenza shots and Glaxo’s adjuvants, which enhance the body’s immune response. Sanofi also has a messenger RNA vaccine in development. Shiver said both candidates reported “compelling” data in pre-clinical studies.
“They showed very, very high levels of neutralizing antibodies in monkeys that are comparable to levels in humans who recovered from the COVID-19 infection,” Shiver said of the pre-clinical studies, which are to be published in medical journals later this year. That data gave Sanofi confidence as it moves to the next stage, he said.
As Sanofi turns its attention to trial enrollment, it’s focused on recruiting a diverse cohort that reflects different geographies, races, ethnicities, genders and ages.
“Older people, unfortunately, people like me over the age of 50, tend not to respond as well to vaccines,” Shiver said. Sanofi is targeting the enrollment of 140 people over age 50 to identify a vaccine formulation that’s best suited for them, he said. The Sanofi-Glaxo vaccine will likely require a two-dose regimen.
COVID-19 vaccine clinical trials have thus far relied on test pools with largely White participants, though Shiver said Sanofi will be focused on recruiting “tremendous diversity” in the 30,000-person phase 3 trial it aims to start in December. It will take place in multiple countries, and particularly where COVID cases continue to rise. Sanofi is currently consulting with epidemiologists on how to best design the trial.
The Sanofi partnership is one of seven vaccine collaborations Glaxo is involved in after the company decided to use its adjuvant system to work with multiple candidates. The British drugmaker has also partnered with Chinese biotechnology company Clover Biopharmaceuticals and Canada’s Medicago Inc.
The Trump administration’s “Operation Warp Speed” effort is providing as much as $2.1 billion to Sanofi and Glaxo to fast-track its shot. If successful with a regulatory approval in the first half of 2021, the companies plan to make one billion doses next year.
“That’s all feasible if the pandemic continues in the way that it’s been proceeding so far this year,” Shiver said. “I expect cases are going to accumulate later this year when our phase 3 trial starts.”