VLPs are molecules that closely resemble a virus. They are not infectious since they do not contain genetic material. Vaccines that use VLPs train the immune system to recognize a virus and launch an attack if a person gets infected.
Medicago's vaccine is different from all authorized COVID-19 vaccines. Whereas other vaccines target only the spike protein, the molecule used by the coronavirus to infect host cells, the plant-based shot uses VLPs that resemble the overall structure of the Wuhan coronavirus.
A small Phase 1 study shows that recipients of the vaccine produce 10 times as many antibodies as people who have had COVID-19. The data also indicate no links to blood clots, which have been reported in people inoculated with the Johnson & Johnson and AstraZeneca vaccines.
"Thus far, the safety profile from the Medicago pre-clinical data as well as the Phase 1 and Phase 2 data has identified nothing concerning regarding blood clotting or any other safety flags," Dr. Mark Carlson, the principal investigator for Be Well Clinical Studies, the Nebraska arm of the trial, told KETV.
The vaccine can be distributed easily since it does not have to be stored at freezing temperatures. In addition, it can be manufactured quickly for less than the cost of other vaccines, according to Dr. Matthew Hong of Wake Research in North Carolina, which is also conducting trials for Medicago.
"All you have to do is extract the spike protein from the plant from the leaves, and you have the vaccine," Hong told ABC News 11. "You don't need all the background and all the other support systems."
The firm is currently recruiting 30,000 volunteers for a late-stage trial. To qualify, volunteers must be aged 18 years or older and have not had or been vaccinated for COVID-19. This is increasingly difficult because around 50.7 percent of the adult American population has received at least one dose.
"Our pool of potential subjects is shrinking daily, and so Medicago is trying to amplify this trial as quickly as possible," Carlson said. The firm hopes to have the results by fall for submission to American drug regulators. (Related: America has NO PLAN for coronavirus other than a vaccine – what about nutrition and herbs?.)
Researchers are also looking into herbs to treat COVID-19. In Thailand, healthcare providers have been using an extract of the Asian plant fah talai jone to treat mild to asymptomatic infections. Multiple patients have recovered from the disease after taking the herbal extract for just five days.
Also known as green chiretta or Andrographis paniculata, the herb has been used for centuries in Ayurveda and Traditional Chinese Medicine to treat lung infections. Its antiviral properties are attributed to the compound andrographolide, which also has antioxidant, anti-inflammatory and anticancer properties.
In a study last April, Thai researchers treated six COVID-19 patients with 180 milligrams of andrographolide. All participants had mild symptoms, such as sore throat, headache, cough and runny nose.
Each participant's condition improved after three days, and their symptoms were gone after five. In addition, none of the participants experienced any side effects.
"We are confident that fah talai jone can cure COVID-19 patients who have mild symptoms and are asymptomatic," said Dr. Kwanchai Wisitthanon, the director-general of the Department of Thai Traditional and Alternative Medicine, which led the study.
Last December, Thailand's Ministry of Public Health approved the use of the extract for treating the early stages of COVID-19. The use of the herbal treatment was on a voluntary basis and was available only for people between the ages of 18 to 60 years who exhibited minor symptoms. It should be administered within three days of confirming an infection, the ministry said.
PlantMedicine.news has more on herbal treatments for COVID-19.