The longevity and bio-hacking sector of medicine is known to be highly experimental, with a lot being pushed by fitness and health influencers that still requires significant testing.

 

One of the compounds that is now getting its time in the spotlight is rapamycin, which, according to Dr Vassily Eliopoulos, a longevity expert trained at Cornell University and co-founder and chief medical officer of Longevity Health, is the most controversial drug in this market at present.

Taking to Instagram on April 9, Dr Vass explained what the drug is, and how far it is along in the testing process, and the likely effects of administering it in humans.

 

What is rapamycin?

The drug rapamycin has been approved by the FDA since the 1990s, shared Dr Vass. He wrote in the caption, "Rapamycin has extended lifespan in every animal model it's been tested on. Longevity physicians are prescribing it off-label to healthy adults. The medical establishment is divided. Biohackers are self-experimenting based on papers they read online."

Known for its antibiotic properties, rapamycin was discovered in the 1970s from soil bacteria on Easter Island. "It was initially developed as an antifungal, then became widely used as an immunosuppressant in organ transplant medicine, where it's been FDA-approved for decades," noted the physician.

However, when it comes to applications for longevity, the story is completely different. According to Dr Vass, rapamycin is being used by biohackers in low, intermittent doses to inhibit the cellular pathway mTOR, which is the most important regulator of ageing, cell growth, and metabolic function in the body.

"mTOR is essentially a cellular growth switch. When it's on: your cells grow, divide, and build. When it's off: your cells clean house, clearing damaged proteins, recycling cellular debris, and performing the maintenance work that keeps ageing at bay," explained Dr Vass.

With age, mTOR activity increases. Therefore, the cleaning cycle slows down, and the damaged cellular material accumulates. By inhibiting the mTOR function, rapamycin forces the clean-up cycle to run.

Has rapamycin been tested for humans?

Rapamycin has shown significant positive effects when it comes to longevity in animals.

"Animal studies have shown that decreased mTOR signalling extends lifespan by up to 20% in yeast, 19% in worms, 24% in flies, and up to 60% in mice," revealed Dr Vass. "Crucially, in mice, rapamycin extended lifespan even when started in mid-life."

According to the physician, no other compound has shown this much consistency across this many species to date. However, among humans, the study of rapamycin is still in its early stages.

The PEARL trial (in prenatal fetus) has shown that low-dose intermittent rapamycin "was well tolerated over one year with modest improvements in biological ageing markers," noted Dr Vass.

"One cohort study suggested users may have reduced biological age by nearly four years, but based on group averages, not individual data," he elaborated. "The animal data is compelling. The human data is early. Both are true simultaneously, and anyone telling you otherwise is oversimplifying."

Possible risks of using rapamycin

Dr Vass cautioned that the dose, timing, and protocol matter enormously when taking rapamycin for longevity purposes. It is not a drug to be self-prescribed. He listed the possible risks of the drug as follows:

• Transplant doses: significant immunosuppression and infection risk


• Low intermittent longevity doses: better profile, but not risk-free


• May blunt muscle protein synthesis, relevant if you're training hard


• Elevated lipids have been observed in some trials


• Long-term safety data in healthy adults doesn't exist yet

"New academic trials are now underway, specifically designed to establish optimal dosing, safety thresholds, and long-term outcomes in healthy older adults, the rigorous human data the field has been missing," noted Dr Vass. "It is a serious tool that warrants serious clinical oversight, not biohacker self-experimentation."