A small study conducted by a team of researchers from Johns Hopkins University has offered a hint that an extra dose of COVID-19 vaccines just might give some organ transplant recipients a needed boost in protection.
The study comes amid the uncertainty revolving around the millions of transplant and cancer patients who take immune-suppressing medicines on how really protected they are from the Covid vaccine due to a weaker immune system.
The study published in Annals of Internal Medicine has so far tracked only 30 transplant patients.
However, researchers believe that it's an important step toward learning if extra doses could help rev up their weak immune system.
According to the researchers, although the booster vaccine didn't help everybody, among the 24 patients who appeared to have no protection after the routine two vaccinations, eight of them developed some virus-fighting antibodies after an extra shot.
Meanwhile, six others who'd had only minimal antibodies all got a big boost from the third dose.
Dr Dorry Segev, a Hopkins transplant surgeon who helped lead the research said that the study was encouraging and added that just because an immune-compromised patient is fully negative after two doses doesn't mean that there's no hope.
For transplant patients, powerful immune-suppressing drugs prevent rejection of their new organs but also leave them extremely vulnerable to the coronavirus. They were excluded from initial testing of the COVID-19 vaccines, but doctors urge that they get vaccinated in hopes of at least some protection.
The Hopkins team recently tested more than 650 transplant recipients and found about 54% harboured virus-fighting antibodies after two doses of the Pfizer or Moderna vaccines — although generally less than in otherwise healthy vaccinated people.
It's not just a concern after organ transplants. According to researchers, those who used particular kinds of immune-suppressing drugs produced dramatically lower levels that are a cause for concern.
And guidelines issued in France recommend a third COVID-19 shot for certain severely immune-suppressed people, including transplant recipients, Segev noted.
The U.S. hasn't authorized extra COVID-19 vaccinations. But around the country, a growing number of immune-compromised patients are seeking third doses on their own — the people Hopkins sought to test.