Coronavirus: British and Russian vaccine makers are set to begin clinical trials combining two vaccines.
Scientists developing the AstraZeneca-Oxford vaccine and Russia’s Sputnik V will try a combination of their respective vaccines by the end of the year, Russia’s sovereign wealth fund announced on Friday, in hopes of strengthening the efficacy of both.
Vaccination often requires one injection and then a boost, and the process can take two forms: giving the same vaccine multiple times, a technique known as “homologous boosting,” or combining different, yet similar vaccines, called “heterologous boosting.”
By combining different but similar vaccines, AstraZeneca and the Russian Investment Fund said they were hoping to boost the immune protection of people who may receive the injections.
The Gamaleya Research Institute of Epidemiology and Microbiology in Moscow, which develops the Sputnik V vaccine, uses two different human adenoviruses to develop its product. AstraZenca uses an adenovirus that infects chimpanzees.
The AstraZeneca vaccine, which is developed at the University of Oxford, showed encouraging but head-scratching results: two doses of the vaccine provided stronger results (90 percent efficacy) when the first dose was only at half strength, than when two full-dose shots were injected (a 62 percent efficacy).
In Russia, the Sputnik V vaccine showed an efficacy rate of 95 percent in preliminary results from a clinical trial, but such results were based on an unspecified small group of volunteers, raising skepticism from experts.
The Russian Investment Fund said AstraZeneca and the Gamaleya Research Institute would begin clinical trials by the end of the month. Kirill Dmitriev, the fund’s C.E.O., hailed the partnership as “an important step toward uniting efforts in the fight against the pandemic,” and AstraZeneca said it “could provide an additional approach to help overcome this deadly virus.”
The announcement comes days after both Britain and Russia began rolling out of a vaccine, the first two countries in the world to do so. Britain has used the Pfizer/BioNTech vaccine, and Russia has administered the Sputnik V vaccine.
A British government official said earlier this week that scientists were reviewing whether it was safe to combine and match vaccines.
“What it means is that you give one vaccine to get the immune system triggered up and another one to then boost it further with a different vaccine,” England’s chief scientific adviser, Sir Patrick Vallance, said in an interview with Sky News. “That’s an established way of getting the immune system geed up.”
Russia drew widespread criticism when it registered its Sputnik V vaccine for emergency use in August before completing a Phase 3 clinical trial to measure its efficacy, yet President Vladimir V. Putin of Russia has boasted that it was the first vaccine in the world to receive government approval.
— Elian Peltier and Derrick Bryson Taylor The New York Times