The experimental vaccine mRNA-1273 appears to lead the race for the first available vaccine against Covid-19. The vaccine, developed by modern biotech, has evolved from Phase I trials to a large Phase 2 clinical trial.
The firm is confident that Phase 3 trials will begin in early summer to determine the efficacy of the vaccine, indicating that the vaccine may have a chance to reach the market by the end of 2020 or 2021.
mRNA-1273 is an experimental vaccine using RNA technology to express viral antigens in the body. The antigen used in these aggregates is the S-protein or spike protein found on the outer surface of the virus, a strain of SARS-Cov-2 - coronavirus that causes Covid-19.
During an infection, coronavirus spike proteins are used to host cell receptors. Prior to binding, spike proteins undergo an enzymatic activation by the cell surface protease TMPRSS2, which facilitates the binding of Spike to the angiotensin-converting enzyme 2 (ACE2) receptor.
Once, the coronavirus is able to gain access to the host cells, where its replication cycle begins. During this infectious process, the host immune system is exposed to spike proteins, which stimulate the production and release of antibodies.
Unfortunately, the immune system is slow to react during an initial infection, but when antibodies are present - as in the case of a second exposure - the body is capable of producing a more robust immune response.
If this reaction is successful, a person is considered immune to the pathogen. Slow response during primary infection that leads to clinical presentation of Covid-19 and negative health outcomes.
Vaccines try to bypass this infectious process and go directly to immunity.
mRNA-1273 works by introducing a small mRNA transcript into the host cell, which acts as a blueprint for the cell to start producing spike proteins.
Once generated, these viral antigens can go on to produce antibody release, but the infection is transmitted to the individual because the vaccine does not contain whole or active viruses.
RNA-based vaccines are a modern and innovative vaccine approach. Clinical trials seek to determine their effectiveness in producing permanent immunity. Not all vaccines that introduce viral antigens are successful.
Many require the administration of live-attenuated viruses - fully active viruses that have been weakened in such a way that they are unable to cause infection to stimulate a vigorous immune response.
As mRNA-1273 advances in clinical trials, it indicates that the vaccine is effective in generating immunity to Covid-19.
Modern previously reported that mRNA-1273 may be available to select as soon as possible this fall, a high-need population such as health care workers. Reports that the vaccine has been approved for further testing are a positive sign.
The vaccine will be tested on a group of 600 participants. Phase 3 trials are already being developed and should begin in early summer. Officials feel that from this timeline it is likely that the vaccine may be available as early as 2021.
Even with the release of a vaccine, many questions still remain. Will the vaccine provide permanent immunity, or will it need to be updated from year to year - as in the case of influenza?
The coronavirus was originally thought to have a relatively stable genome, aiming to maintain it from rapid mutation and to make it more difficult with vaccines.
Reports have surfaced this week indicating that SARS-CoV-2 has mutated since the onset of the pandemic in late 2019, expressing concern that several strains may cause Covid-19 infection.
A successful vaccine against Covid-19 will be a commemorative achievement in the fight against the disease. Many feel that a vaccine is an important component for countries to reopen and return to an almost normal way of life. Results of Modern's clinical trials will be available by the end of 2020.
Comments
Post a Comment