A soil sample from Easter Island, collected more than half a century ago, yielded a microorganism that produces one of the most important medicines of the modern era. The drug, rapamycin, has generated billions of dollars in revenue for pharmaceutical companies and opened up entire new fields of biomedical research, including the study of aging. However, the Indigenous people of the island, known as Rapa Nui, have never received any compensation or recognition for the discovery, sparking a complex debate over ethics, Indigenous rights, and the commercialization of natural resources.
Named after the island’s traditional name, Rapa Nui, rapamycin was first approved in 1999 as an immunosuppressant to prevent the rejection of transplanted organs. Its applications have since expanded significantly to include use in drug-eluting stents for heart disease and the treatment of certain cancers. More recently, scientists have focused on the drug’s ability to inhibit a key cellular protein called mTOR, which regulates cell growth and metabolism, uncovering its potential to extend lifespan and combat age-related diseases. This pharmaceutical success story stands in stark contrast to the lack of benefits for the community whose land was the source of the foundational biological material, raising persistent questions of equity and biopiracy.
The 1964 Medical Expedition
The story of rapamycin begins not with a pharmaceutical company, but with a Canadian-led scientific mission called the Medical Expedition to Easter Island (METEI) in 1964. Organized by surgeon Stanley Skoryna of McGill University, the expedition’s primary goal was to document the health and biosphere of the isolated Rapa Nui population before a new airport threatened to end their relative seclusion. As part of this broad effort, a microbiologist on the team, Georges Nogrady, collected soil samples from across the island.
One of the expedition’s original hypotheses was that unique antibacterial compounds in the soil might explain a low incidence of tetanus among the Rapa Nui people, who often walked barefoot. Nogrady gathered numerous samples, including one from the crater of the Rano Kau volcano, a place local legend associated with healing powers. Upon returning to Canada, these soil samples were shared with Ayerst Research Laboratories in Montreal for analysis. There, they were handed to microbiologist Surendra Sehgal, who was tasked with screening them for novel antimicrobial agents.
From Soil Bacterium to Miracle Drug
At the Ayerst labs, Dr. Surendra Sehgal and his team isolated a specific bacterium from the Rapa Nui soil sample, identified as Streptomyces hydroscopicus. They discovered that this microorganism produced a powerful chemical compound with strong antifungal properties. The company named the new molecule rapamycin, a direct tribute to the island’s Indigenous name, Rapa Nui. Initial development focused on its potential as a topical antifungal medication.
The project faced corporate hurdles, and at one point, Sehgal famously stored the bacterial cultures in his home freezer to prevent them from being destroyed during a company shutdown. His persistence paid off. Further testing revealed that rapamycin had potent immunosuppressive and antiproliferative effects, meaning it could suppress the immune system and stop cells from dividing. This shifted its development path entirely, leading to trials for preventing organ transplant rejection. In 1999, the U.S. Food and Drug Administration approved it for this purpose under the brand name Rapamune. This discovery also led researchers to identify its biological target, a critical protein kinase that regulates cellular growth, now known as the “mechanistic target of rapamycin,” or mTOR.
Expanding Medical and Scientific Impact
The identification of mTOR as rapamycin’s target revolutionized cellular biology. Scientists realized this protein is a master regulator of cell metabolism, growth, and aging in organisms from yeast to mammals, including humans. This has made rapamycin one of the most studied molecules in medicine, with over 59,000 journal articles referencing it. Its ability to inhibit mTOR led to new applications far beyond transplantation.
Clinical Applications
After its approval for use in kidney transplants, rapamycin’s ability to halt cell proliferation was harnessed for other treatments. It became a key component in drug-eluting stents, which are coated with the substance to prevent the regrowth of tissue that can clog arteries after an angioplasty. Derivatives of the drug, known as rapalogs, were also developed as cancer therapies, proving effective against certain types of advanced kidney cancer and other tumors.
The Frontier of Longevity Research
Perhaps the most compelling modern research involves rapamycin’s effect on aging. Because the mTOR pathway is strongly linked to how cells respond to nutrient availability, inhibiting it can mimic the effects of caloric restriction, a state known to extend lifespan in many species. Studies have repeatedly shown that rapamycin can significantly prolong the lifespan of laboratory animals like mice, even when administered late in life. While its use as a general anti-aging drug in healthy humans is not yet approved due to potential side effects like immune suppression, the research has sparked immense interest and ongoing clinical trials exploring its potential to delay or prevent age-related diseases.
A Growing Controversy Over Compensation
Despite the billions of dollars in revenue generated by rapamycin and its derivatives, the Rapa Nui people have received no financial benefits or formal acknowledgment for their contribution to the discovery. This has fueled an ethical debate centered on accusations of biopiracy—the practice of commercially exploiting natural resources or Indigenous knowledge without permission or fair compensation. The 1964 expedition occurred long before international agreements like the Nagoya Protocol, which now establish frameworks for benefit-sharing, were put in place.
Arguments against compensation often point out that the Streptomyces hydroscopicus bacterium has since been found in soil elsewhere, suggesting the Rapa Nui sample was not entirely unique. Another argument is that since the islanders did not actively use the bacterium or have prior knowledge of its medicinal properties, it cannot be considered a resource that was “stolen” from them. However, proponents of compensation counter that the discovery was not made in a vacuum. It was a direct result of the Canadian expedition’s presence on the island to study its people. The specific soil sample from Rapa Nui was the one that launched the entire field of research and commercialization, making it the foundational element of the drug’s success story.