Russian adenovirus vector-based vaccine candidates include virus-like particles, and recombinant protein-based vaccines.
Gamaleya Research Center received an international patent for Ebola vaccine. The vaccine, which consists of live-attenuated recombinant vesicular stomatitis virus (VSV) and recombinant adenovirus type-5 (Ad5) expressing Ebola envelope glycoprotein. The most common adverse event was pain at the injection site, although no serious adverse events reported.
The Ebola virus vaccine strategies evaluated by the World Health Organization in response to the 2014-2016 outbreak in West Africa included a heterologous primary and booster vaccination schedule of the adenovirus type 26 vector vaccine encoding Ebola virus glycoprotein Ad26.
These results, together with the induction of both humoral and cellular immune responses, support largescale evaluation of this candidate vaccine in an ongoing phase 3 programme, the study said in its findings. In particular, the vaccine elicited glycoprotein-specific humoral response in non-human primates, with significantly increased titres 28 days after vaccination, and even higher titres on day 42. At day 42, glycoprotein-specific antibody titres were 2,540 in volunteers immunized at half dose. Indeed, the strong immune response to the vaccine may elicit long-term protection.
Importantly, the data also demonstrate that a vaccine based on VSV – glycoprotein and Ad5-glycoprotein does not cause serious side effects, and has a good safety profile in healthy adult volunteers. Based on Guidelines for Preparing Core Clinical Safety Information on Drugs, 20 some of these adverse events were very common (myalgia, headache, fatigue, arthralgia, and pain at the injection site) or common (erythema, swollen lymph node, nausea, gastrointestinal syndrome, and loss of appetite).
This drug possesses antiviral activity for marburg, yellow and Ebola virus infection is BCX4430. A second Phase II trial, involving 1,200 volunteers, was initiated in Africa with the first trial commenced in Sierra Leone, Liberia, and Guinea in 2015.
With the Phase 1 trial ongoing. This potentially creates a prospect for a future vaccine development. Though additional results are still forthcoming, this phase 1 study marks the first time any nucleic acid vaccine was used in humans. The vesicular stomatitis virus ( VSV ) platform is a replication competent vaccine that has been shown to generate both cell – mediate immune responses, and the remarkable expression of foreign antigens. Notably, this vector, pseudotyped with the Ebola virus ( EBOV ) GP.
Currently, more than 100 candidate COVID-19 vaccines are in development worldwide with at least 8 of them in the process of human trials.
The research was supported by the National Institute of Allergy and Infectious Diseases ( NIAID ). This is an important step in evaluating this early-stage experimental vaccine and phase 3 trials are now underway. One participant given the higher dose Sputnik V vaccine reported severe fever along with severe symptoms of fatigue, shortness of breath, and muscle pain – however these adverse reactions persisted for less than 48 hours. The next step in studying the vaccine is to confirm that it can effectively protect against SARS – CoV-2 infection.
The first COVID-19 vaccine to reach phase I clinical trial is safe and able to generate an immune response against the novel coronavirus in humans, says a new research published in The Lancet. Professor Feng – Cai Zhu, Jiangsu Provincial Center for Disease Control and Prevention, China, says : ” The phase 2 trial adds further evidence on safety and immunogenicity in a large population than the phase 1 trial. The vaccine induced a neutralising antibody response in 59% (148) and 47% (61) of participants, and binding antibody response in 96% (244) and 97% (125) of participants, in the high and low dose groups, respectively, by day 28.
Most adverse events were mild or moderate, with 83% (30) of those receiving low and middle doses of the vaccine and 75% (27) in the high dose group reporting at least one adverse reaction within 7 days of vaccination.
The authors note that both the antibody and T-cell response could be reduced by high pre – existing immunity to adenovirus type 5 – the common cold virus vector carrier.
Professor Wei Chen, Beijing Institute of Biotechnology, China, says: “Since elderly individuals face a high risk of serious illness and even death associated with COVID-19 infection, they are an important target population for a COVID-19 vaccine”.
It was approved in the United States in December 2019. It contains a human adenovirus serotype 26 ( Ad26 ) expressing the Ebola virus Ankara – Bavarian Nordic (MVA-BN) Filo-vector (Ad5) with the glycoprotein gene from ZEBOV.
This study was conducted in accordance with a protocol approved by an Institutional Animal Care and Use Committee of the National Institutes of Health. in Phase – I clinical trial in 2016, it proved to be a safe and effective vaccine and is expected to be approved this year by the U. S. FDA. A new vaccine trial has shown promise in the first human trials. These results represent an important milestone”, co – author Wei Chen, of the Beijing Institute of Biotechnology in China, said in a statement.
“Volunteers were enrolled from one site in Wuhan, China, and assigned to receive either a single intramuscular injection of the new Ad5 vaccine at a low dose ( 5 × 1010 viral particles, 36 adults ), middle dose ( 1×1011 viral particles, 36 adults ), or high dose ( 1.5 x 1011 viral particles, 36 adults )”.
The researchers tested the volunteers’ blood at regular intervals following vaccination to see whether the vaccine stimulated both arms of the immune system: the body’s humoral response, which depends on a group of T-cells. Further research will be needed before this trial vaccine becomes available to all.
“The trial demonstrates that a single dose of the new adenovirus type 5 vectored COVID-19 (Ad5-nCoV) vaccine produces virus-specific antibodies and T cells in 14 days”, said study co – author Wei Chen from the Beijing Institute of Biotechnology.
A single dose of an experimental Ebola virus (EBOV) vaccine completely protects monkeys against the newly emerged West African Ebola strain when given at least seven days before exposure, and partially protects them if given three days prior, says a new study. Citing the main limitations of the trial, The authors said the study had a small sample size and was conducted in relatively short duration, and lack of randomised control group, which limits the ability to pick up rarer adverse reactions to the vaccine or provide robust evidence for its ability to generate an immune reaction.
Trials involving 1,077 people showed the injection led to them making antibodies and white blood cells that can fight coronavirus. “Thus, preventing infection and disease in the primates upon high amounts of exposure to live SARS – CoV-2 virus ” , Wei Chen added. This schedule has been shown to induce immune responses that persist for eight months after primary immunization, with 100 percent of vaccine recipients retaining Ebola virus glycoprotein – specific antibodies.
