A clinical trial testing the health benefits of an experimental drug in a new combination has shown promising results, safely reducing infections in elderly volunteers around 40 percent by reversing the effects of aging on the immune system.
It's not exactly a fountain of youth in a pill, but the researchers behind the discovery are hopeful its effects will translate into healthier and possibly even longer lives for an ageing population.
The double blind, randomised study carried out by Novartis Institutes for Biomedical Research in Massachusetts put 264 volunteers aged 65 and over on a six week course of two drugs designed to block a protein called the mammalian target of rapamycin (mTOR).
This enzyme is a key player in the regulation of various cellular processes, regulating their growth, survival, and movements. It's also implicated in the 'pruning' of neurons that happens when the brain is still developing.
It also seems to be integral to the impacts of ageing biology: blocking a similar enzyme in a variety of experimental organisms such as fruit flies gives them a longer lifespan.
Drugs that inhibit mTOR are already used to treat cancer and assist organ transplants, so the idea of exploring their potential as a way to combat the effects of ageing in humans has been too tempting to resist.
Inhibiting the enzyme gave them the stem cells of a healthy whipper-snapper, allowing vaccines to work far better.
This isn't the first time Novartis has conducted a human trial using an mTOR inhibitor, either.
An earlier experiment conducted several years ago has already found using just one of the two drugs increased their immune response to the flu vaccine by 20 percent.
In this more recent human trial, the researchers combined two types of inhibitor in an effort to improve on their earlier findings, delivering a one-two punch that was tailored to prevent mTOR from working.
Subjects were randomly placed into one of eight groups – four different dosing regimens, and four matching placebo groups.
After six weeks of doses and a two week break, the entire group received a seasonal flu shot, followed several weeks later by blood tests to detect antibodies.
Their blood results showed once again a 20 percent increase in influenza antibodies compared with the placebo groups.
Over the course of a year, the health of both groups was tracked through weekly phone conversations.
There didn't seem to be any adverse side effects from either of the inhibitors. But those who received a combination of the two inhibitors experienced an average of 1.49 infections over those twelve months, compared with 2.41 infections among those who took a placebo.
That might not seem like a big deal, but for an ageing body, one less episode of bronchitis or gastro in a year could turn out to be a life saver.
Lower respiratory infections are the leading cause of death from an infection, especially among the elderly, meaning drugs like these could help a lot of people avoid an early grave.
Having ways to make the most of vaccines would also help make the general community safer.
"In the future, a larger percentage of our population is going to be older," immunologist Deborah Dunn-Walters told Layal Liverpool at The Guardian.
Dunn-Walters wasn't involved in the research, but she sees the benefits in making a drug like this available.
"If older people don't respond well to vaccinations, then there will be more and more people that aren't protected and who can potentially pass on infections to others in the population," Dunn-Walters says.
It's far too early to tell how much to expect from anti-ageing drugs like these. And nothing beats old age like eating well and staying active.
But even if they don't lengthen our lives as they do for other organisms, an immune boost would still be worth chasing in our later years.
This research was published in Science Translational Medicine.