Medical news network August 10th Johnson announced in July 24th the world's first HIV vaccine in human clinical trials, this multicenter, randomized, placebo-controlled, double-blind phase 1/2a clinical trial recruited 393 healthy volunteers, volunteers from the United States, Rwanda, Uganda, South Africa and Thailand. The results showed that the volunteers of HIV vaccine was well tolerated, and produced the antibody against HIV 100%.
Exposure to HIV alone reduced the risk of infection by 94%
Johnson is the world's largest scale, diversification of products in medical and health care products and consumer care products company, its financial support is an important reason for this vaccine has achieved remarkable results, the specific test undertaken by Yang Sen pharmaceutical company and its subsidiary, but the technology from the American Medical College of Harvard University and other research institutions.
The HIV vaccine is a mosaic vaccine, namely the use of a variety of antigen HIV (gene fragments) together, forming a strong stimulating effect on the immune system and can generate effective antibody vaccine, called appROACH vaccine. The appROACH vaccine is, at first, exhilarating in effect. In addition to the 100% subjects who developed antibodies against the HIV virus, but also let the subjects single exposure to the AIDS virus (HIV) infection risk was reduced by 94%, and there are 66% people in the 6 exposure to HIV is still protected, not infected by HIV.
The vaccine trial used a "first free booster immunization" strategy, in which subjects received 4 doses of vaccination, the first two vaccines were initial free, and the latter two were intensive immunizations. After 48 weeks, the subjects did not produce any side effects, and blood tests showed that all human bodies produced antibodies against HIV. The risk of HIV infection was reduced by 94% in the actual assessment of the subjects' protection.
The AIDS vaccine mosaic have a significant effect the main reason is that the vaccine designed according to the characteristics of HIV, the most important is the variety of antigen by HIV, which is selected from a plurality of different subtypes of HIV virus gene, the HIV antigen produced by viral vectors, the composition containing multiple HIV antigen vaccine.
Mosaic vaccines completed animal experiments a few years ago
Mosaic mosaic AIDS have been developed several years ago and tested on animals. In 2013, researchers at the Harvard University School of medicine, who developed mosaic vaccines, reported in the journal cell that they developed mosaic vaccines using 3 major proteins of the virus.
The HIV of several gene splicing or embedded in the main reason vaccine is that these antigens can effectively stimulate the immune system, and cause the immune system to produce antibodies to the antigen for a large number of several, to neutralize the AIDS virus (2) to prevent the AIDS virus invasion of human immune cells T objective.
At that time, the researchers of the vaccine inoculation test and Ganges RIver monkey, with the most pathogenic SHIV (SHIV, similar to the human immunodeficiency virus HIV), 6 simulated AIDS virus natural infection in Ganges RIver monkey, to test the effect of vaccine. The results showed that only 3 of the 12 Ganges RIver monkeys vaccinated against human monkey chimeric immunodeficiency virus were protected from infection after 6 consecutive exposure to human monkey chimeric immunodeficiency virus. However, compared with the unvaccinated control group, 12 Ganges RIver monkeys (who were all infected after 3 exposure to human simian chimeric immunodeficiency virus), the protective effect of mosaic vaccine on Ganges RIver monkeys was as high as 87% to 90%.
Based on the results of the study, Harvard University researchers concluded that mosaic vaccine may not only be effective for humans, but also may reduce the probability of human infection with HIV by about 90%. Now, Yang Sen's appROACH mosaic vaccine tested Johnson's risk of infection by 94%, suggesting that the initial test had been tested.
How does mosaic vaccine come from?
Mosaic vaccine, also known as mosaic vaccine, was launched in 2009 in Thailand AIDS vaccine RV144 large clinical trials, becoming the first choice of AIDS vaccine researchers in various countries. At the time, a large study in Thailand showed that RV144 could only reduce the rate of HIV infection by 31%, but it was the most effective vaccine.
A vaccine that protects only 31% of the population is obviously not ideal and requires at least 60% of the population to be protected against being called an effective vaccine. Later, the researchers through extensive and in-depth research, believe that the protection effect of RV144 vaccine is limited, because the lack of effective stimulation of antigen and antigen on behalf of its defects, therefore, the research focus shifted to the mosaic vaccine. The design and development of vaccines for certain diseases, of course, should be based on the characteristics, structure, transmission features, and target targets of pathogens that cause the disease. Now, the design of AIDS vaccine transfer to the structural features of HIV, because the structure is quite complex, and variability is great.
HIV, if not the most complicated virus in the world, is also one of the most complex viruses. The international Virus Classification Committee divides the HIV into two major types: HIV-1 and HIV-2. Currently, AIDS is caused mainly by HIV-1 throughout the world. HIV-2 triggered AIDS mainly in West Africa epidemic, HIV-2 pathogenicity is lower than HIV-1, and spread faster than HIV-1. HIV-1 and HIV-2 differ greatly in gene sequences, and their envelope glycoproteins often do not cause cross immune responses. Therefore, the AIDS vaccine is now developed mainly for HIV-1 vaccine.
Even though there are many subtypes in HIV-1. The AIDS virus in the structure is very complex, many subtypes, if only a single subtype and one of these one or two genes as antigens for making vaccines, even if the body's immune system to produce antibodies, but also for a one or two antibody antigen, not enough to cause a fatal blow to the AIDS virus, the virus can also survive and the infection of human T cells.
Therefore, not only clinical treatment, especially in vaccine research and development, clinicians and researchers pay special attention to the AIDS caused by different genotypes of hiv. At the same time, the formation of AIDS vaccine has developed a core idea, that is, as far as possible the use of all antigenic components of hiv. However, this is an ideal requirement, and now difficult to achieve, we can only retreat and secondly, the use of multiple antigens of hiv. And the volunteers also need to experiment with diversity and global, only in countries in different regions of the country volunteers to test the effect, in order to prove a vaccine broad-spectrum resistance (effectiveness). This is the appROACH mosaic vaccine this time.
