- Another coronavirus vaccine candidate seems to be effective and safe for older adults who were enrolled in a limited study.
- The results are preliminary, and the trials were limited to only 20 participants. But Moderna said its mRNA vaccine is safe and effective for people older than 56.
- Vaccines might not be as effective for the elderly, who are have a higher risk of developing serious symptoms. Moderna’s drug produced neutralizing antibodies and T cells in older patients, the company said.
Getting vaccines approved once they’re found to be safe effective is only the first hurdle. What will follow next will be equally challenging. The actual vaccination of the general public will likely happen in phases, as there won’t be enough supply to meet demand. Some of these drugs are being mass-produced before the clinical trials are completed to hasten delivery in case the drugs are approved. But even so, immunizing the world’s entire population will take years, and each country will have to determine its vaccination schedule.
US health officials have not come out with an actual vaccination protocol, but Dr. Anthony Fauci said in the past that it would be several months into 2021 before most people can get a vaccine. Those most at risk, such as the elderly and frontline workers, could be immunized as soon as late 2020 assuming all goes well. But for that to happen, drug makers need to prove the vaccines are effective for a few specific types of patients, like the elderly. Thankfully, we’ve got a second early announcement that says a novel coronavirus vaccine candidate induces the desired immune response in older people without provoking severe side effects.
It was Pfizer and BioNTech that offered the first glimpse of hope a few days ago when the two companies published additional data about their leading COVID-19 vaccine candidate. They said the drug induced an immune response in older volunteers similar or better than the immune response seen in COVID-19 survivors. Specifically, the drug taught the immune system to create neutralizing antibodies that would hopefully block the infection. The side-effects were mild and transitory, the two companies said at the time.
Like BioNTech, Moderna also has an mRNA vaccine candidate in the works that reached Phase 3 of clinical trials. Moderna was the first company to start Phase 1 trials in the US. Moderna was also among the first companies to publish Phase 1 data, but it was criticized at the time for how it chose to share the data. The company will hold a conference call to address the new findings.
Also, like the Pfizer vaccine, Moderna’s drug works on older people, CNBC reports. Moderna has not released the full results of the limited study via a press release or a full paper but told CNBC that it tested the drug on 10 adults between the ages of 56 and 70 as well as 10 people over the age of 71.
The participants received two 100 microgram doses of the vaccine 28 days apart, which elicited an immune response. The volunteers developed neutralizing antibodies and killer T cells. The former is needed to block the chemical reaction between the virus and the human cells. In contrast, T cells are expected to provide longer-lasting protection after the first generation of antibodies disappears. Those T cells could handle a secondary infection, as they would recognize the virus and both kill infected cells and instruct B cells to train a new generation of antibodies.
The antibodies were produced in higher numbers than those seen in people who survived the infection, which seems to be great news. The company also said there were no serious adverse effects to the shots, but some patients reported fatigue, chills, headache, and pain at the injection site. Most of the symptoms disappeared within two days, and they’re consistent with reactions to other vaccines.
Moderna’s Phase 3 trial is well underway, but there’s no telling when the data will be available. All Phase 3 trials need to incorporate 30,000 volunteers, and Moderna’s regimen includes a two-shot vaccine administered four weeks apart. Recruiting for Phase 3 started last month.
The final stage of clinical trials will have to produce results that prove both the efficacy and safety of the tested drug, whether it’s Moderna’s or any other vaccine candidate. Without the scientific data, the US should not issue emergency use authorization (EUA) for any vaccine candidate, Dr. Fauci warned, after some reports indicated the Trump administration would move towards an EUA for at least one vaccine in time for the November election.
