The results of the first phase of clinical trials of a vaccine project in China against the new coronavirus demonstrate that it is safe, well tolerated and capable of generating an immune response against Covid-19 in humans.
The person in charge of this clinical trial – the vaccine has to pass three phases – is the Institute of Biotechnology of Beijing, in China, and its results are published in the scientific journal The Lancet.
The study has been done in 108 healthy adults between 18 and 60 years old and shows “promising results” after 28 days, according to the authors, who nevertheless point out that more trials are needed to know if the immune response it causes effectively protects against SARS-CoV-2 infection, which causes Covid-19.
“These results represent an important milestone,” said Wei Chen of the Beijing Institute of Biotechnology, for whom this trial demonstrates that a single dose of the new vaccine, using an adenovirus vector type 5 (Ad5-nCoV), produces in 14 days specific antibodies against the virus and T cells – a type of white blood cell that plays a key role in the immune response.
This makes her “a potential candidate for further investigation,” said Chen, who nonetheless points out that the results should be interpreted with caution, the EFE news agency reproduced.
And, according to The Lancet, the ability to trigger immune responses does not necessarily indicate that the vaccine will protect humans from the disease.
“This result shows promising vision for vaccine development, but we are still a long way from making it available to everyone,” Chen said.
According to the magazine, the project evaluated in this trial is the first one that has been tested in humans.
The vaccine, with the participation of the CanSino company, was well tolerated in all doses, with no serious adverse events reported in the 28 days after vaccination; in any case, most were mild or moderate.
The most common adverse reactions were mild pain, fever, fatigue, headache, and muscle pain.
Within two weeks of vaccination, all dose levels triggered some level of immune response in the form of binding antibodies (which can bind to the coronavirus but do not necessarily attack it); some of the participants had detectable neutralizing antibodies against the new coronavirus.
This also occurred after 28 days, where the majority quadrupled the binding antibodies; half of the participants who received low and medium vaccination doses, and three-quarters of those in the high-dose group showed neutralizing antibodies against the new coronavirus.
The main limitations of the trial, the authors note, are small sample size, relatively short duration, and lack of a randomized control group, limiting the ability to detect rarer vaccine adverse reactions or to provide robust evidence. of its ability to generate an immune reaction.
Phase 2 of the trial has already started in Wuhan City to determine if the results can be replicated and if there are any adverse events for up to six months after vaccination.
Participating 500 healthy adults, 250 volunteers who were given a medium dose, 125 who were given a low dose and 125 who were given a placebo as a control.
For the first time, participants over the age of 60, a large population targeted by the vaccine, were included.
Earlier this week, US pharmacist Moderna reported the “positive” results of its vaccine also in a first phase of experimentation, which demonstrated “potential to prevent Covid-19 disease” in humans.