The U.S. Army will begin testing an Army-developed Covid-19 vaccine among adult volunteers that researchers say can protect against a variety of coronavirus variants.
Army doctors plan to begin testing the protein-based injection Tuesday in up to 72 adults ages 18 to 55 at the Walter Reed Army Research Institute in Silver Spring, Maryland, the institute said. The team will test whether the vaccine safely induces the desired immune response in study subjects.
Initial results of the study could be available in mid-summer. If the data is positive, the Army will likely try to team up with a pharmaceutical company to conduct further testing and develop the vaccine, said Kayvon Modjarrad, director of the institute’s emerging infectious diseases branch.
The experimental shot is among dozens in development, many of which aim to improve the shots available. About 229 human vaccine trials are underway, according to BioCentury, which is tracking the efforts.
Next-generation Covid-19 vaccines could play a role in vaccines if they differ from the current crop, infectious disease specialists and industry analysts say. Vaccines that elicit a different type of immune response or that have a different route of administration, such as a nasal spray or a liquid formulation that can be swallowed, may prove useful as primary vaccines outside of the US or as booster vaccines. In the USA.
The vaccines now in the works can be particularly useful as booster shots in people who previously received Covid-19 vaccines that contain a type of harmless virus known as adenovirus, such as Johnson & Johnson’s and AstraZeneca PLC’s, because those people can develop immunity to adenovirus in a way that could decrease the effectiveness of a technology-based booster vaccine.
Army researchers say their vaccine was protective in studies of monkeys that were exposed to the coronavirus.
And laboratory tests suggest that the vaccine could protect against newer and more transmissible variants of the virus, including those first identified in the UK and South Africa, Dr. Modjarrad said.
“This vaccine can be a good vaccine in terms of covering all the different types of strains,” he said.
If the trial is successful, the vaccine could also be used as a booster shot in people who have previously received one of the now licensed vaccines, to boost immunity against the variants, he said.
The vaccine could be used in a broader population, not just in the military, he said.
Vaccines currently licensed in the US, From Pfizer Inc. with its partner BioNTech SE; Moderna Inc .; and J & J: appear to retain some efficacy against newer virus variants.
However, the J&J vaccine was less effective in the South African part of a large study, where this variant was widely circulated, than in other countries where the study was conducted. And the Pfizer and Moderna vaccines had a reduced neutralizing effect against the strain in laboratory tests with blood samples from vaccinated people compared to their effects on the original viral strain.
Scientists at the Army research institute developed their vaccine by attaching a copy of the spike protein found on the surface of the coronavirus to another protein known as ferritin, which is normally found in human blood and contains iron.
Ferritin proteins form a multifaceted spherical structure that resembles the coronavirus. This, in turn, is designed to trigger an immune response that can help defend against the real virus, if a vaccinated person is subsequently exposed.
The vaccine also contains an ingredient called an adjuvant, which is designed to enhance immune responses.
Army scientists plan to use a similar design to develop a vaccine that could protect not only against Covid-19, but also against other coronaviruses, Dr. Modjarrad said.
Some study volunteers will receive one dose of the Army vaccine and others will receive two doses four weeks apart. Researchers will assess immune responses from blood samples taken approximately two weeks after the second dose or six weeks after the single dose.
Write Peter Loftus at [email protected]