Coronavirus | Vaccine Human Trial | mRNA-1273

How the vaccine will work.

Like other coronaviruses, SARS-Co-V-2 particles are spherical and have proteins called spikes protruding from their surface and have ssRNA as their genetic material. Human cells also have various receptors on their surfaces that the virus can use for entry.


Researchers found that spikes of the virus latch onto human cells using the ACE-2 receptor. After this handshake between the virus and the human cell, some structural changes allow the viral membrane to fuse with the human cell membrane. Then the viral genes can enter the human cell and make more viruses.


The structure of this spike was studied in detail using cryo-electron microscopy. The virus was frozen, bombarded with high-energy electrons, and tens of thousands of images were created and combined to form the 3 D structure.


This is the 3 D structure of SARS-Co-V-2, which helped the scientists to develop a Vaccine called mRNA-1273. When this vaccine is injected into the human cell, it will make the viral protein.

The scientists are hoping that this viral protein will wake up our immune response and protect against the virus.


The mRNA-1273 vaccine has shown promise in animal models, and this is the first trial to examine it in humans. The human trial will enroll 45 healthy adult volunteers of 18 to 55 years of age over approximately six weeks. Study participants will receive two doses of the vaccine via intramuscular injection in the upper arm approximately 28 days apart.


Currently, the study is evaluating different doses of the experimental vaccine for safety and its ability to induce an immune response in participants.


This is the first of multiple steps in the clinical trial process for evaluating the potential benefit of the vaccine. Currently, three groups of 15 people will receive different doses of the experimental vaccine. That is 25 micrograms, 100 micrograms, or 250 microgram dose.

The first four participants will receive one injection with the low dose.


Investigators will review safety data before vaccinating the remaining participants in the 25 and 100 microgram dose groups and before participants receive their second vaccinations.

If the four participants are safe, then the 25 microgram group will be injected, and if they are safe, then the 100 microgram group will be tested, and so on.


Blood samples of participants will be checked from time to time to see if an immune response is developed against the vaccine.


Meanwhile, we can maintain Social distancing measures like self-isolation, sanitization, closure of schools or workplaces, and reduction in person to person contact.