One afternoon in the early 
1980s, Suren Sehgal brought a strange package home from work and stashed
 it in his family’s freezer. Wedged beside the ice cream, it was wrapped
 in heavy plastic and marked, “DON’T EAT!” Inside were several small 
glass vials containing a white paste—all that remained of a rare 
bacterium that today is the foundation of the most promising anti-aging 
drug in decades. Sehgal had been studying it since 1972, when he’d first
 isolated it in a soil sample at Ayerst Laboratories, a pharmaceutical 
company in Montreal.
A Canadian 
medical expedition had collected the soil from beneath one of the 
mysterious stone heads on Easter Island, a speck in the middle of the 
Pacific Ocean. In the dirt, Sehgal had discovered Streptomyces hygroscopicus,
 a bacterium that secreted a potent antifungal compound. This intrigued 
him; he thought perhaps it could be made into a cream for athlete’s foot
 or other fungal conditions. He purified the stuff and named it 
rapamycin, after Easter Island’s native name, Rapa Nui.
It
 soon proved its potential. When a neighbor’s wife developed a stubborn 
fungal skin condition, Sehgal mixed up a rapamycin ointment for her. “It
 was probably illegal,” says his son Ajai Sehgal, but the infection 
cleared up quickly. Suren, a biochemist who’d immigrated to Canada from a
 tiny village in what’s now Pakistan, became convinced that he’d 
stumbled upon something special. Before he could develop it any further,
 however, Ayerst abruptly closed its Montreal lab, and his bosses 
ordered all “nonviable” compounds destroyed—including the rapamycin. 
Sehgal couldn’t bring himself to do it and instead squirreled a few 
vials of Streptomyces hygroscopicus into his freezer at home. 
Most of the staff was fired, but Sehgal was transferred to the company’s
 lab in Princeton, N.J. The plastic package made the move packed in dry 
ice.
When Wyeth, the global
 health-care company based in Pennsylvania, bought Ayerst in 1987, 
Sehgal persuaded his bosses to let him resume his work on the rare 
bacterium. Sehgal found that, besides its antifungal properties, 
rapamycin also suppressed the immune system. It tamps down the body’s 
natural reaction to a new kidney or other organ. Eventually, in 1999, 
the U.S. Food and Drug Administration approved rapamycin as a drug for 
transplant patients. Sehgal died a few years after the FDA approval, too
 soon to see his brainchild save the lives of thousands of transplant 
patients and go on to make Wyeth hundreds of millions of dollars.
In
 the years since, rapamycin has been adapted for numerous uses. Like 
penicillin, it’s a biological agent, so it can’t be patented, although 
derivatives of it can. It’s now used routinely as a coating on cardiac 
stents to prevent scarring and blocking. Derivatives of rapamycin have 
been approved for use against certain kidney, lung, and breast cancers. 
That may be just the beginning. Over the past decade, it’s shown promise
 as a drug that not only can extend life by delaying the onset of 
aging-related diseases such as cancer, heart disease, and Alzheimer’s 
disease, but also postpone the effects of normal aging. With an eye 
toward changing the way millions grow older, Novartis, the $260 billion 
Swiss pharmaceutical giant, has begun taking the first steps to position
 a version of rapamycin as the first true anti-aging drug.
Pharmacological
 history is full of substances that have been purported to delay aging 
or lengthen life span, from resveratrol (the “red wine pill”) in the 
2000s to testicular implants in the 1920s, all the way back to medieval 
alchemists (gold was thought to possess anti-aging properties). Until 
rapamycin came along, however, nothing has actually worked in rigorously
 designed clinical studies.
“People
 have shown that rapamycin extends life span again and again and again,”
 says Matt Kaeberlein, a scientist at the University of Washington and a
 leading researcher in the biology of aging. So far it’s demonstrated it
 can lengthen the lives of mice, not men, but what’s particularly 
exciting is how it did so, Kaeberlein says. The drug appears to delay 
“age-related decline in multiple different organ systems, which is 
something we would expect if we were fundamentally slowing the aging 
process.”
The promise of 
rapamycin, he and others contend, is to treat aging as a contributing 
factor to the chronic diseases that kill people later in life, the way 
we now lower cholesterol to prevent heart disease. “I view it as the 
ultimate preventive medicine,” says Kaeberlein, who’s leading a 
rapamycin study on dogs.
Not 
everyone is convinced. “There are no interventions that have been 
documented to slow, stop, or reverse aging in humans,” says S. Jay 
Olshansky, a professor of public health at the University of Illinois at
 Chicago and a leading critic of purported life-extending supplements 
and treatments. “The batting average is zero.”
Olshansky
 welcomes the advent of therapies like rapamycin, but he doesn’t think 
we know enough yet: “My caution is always no, no, no: Let science do 
what it does and evaluate these interventions for safety and efficacy 
first,” he says. Such admonitions are justified. And yet the enthusiasm 
of scientists such as Kaeberlein is hard to resist. “We have the 
potential to delay the onset of all of these diseases at the same time 
by understanding and intervening in the molecular processes that drive 
aging,” he says. “We now know that that is possible.”
Rapamycin
 works at a fundamental level of cell biology. In the early 1990s, 
scientists at Novartis’s predecessor, Sandoz, discovered that a 
rapamycin molecule inhibits a key cellular pathway regulating growth and
 metabolism. This pathway was eventually dubbed “target of rapamycin,” 
or TOR, and it’s found in everything from yeast to humans (it’s known as
 mTOR in mammals).
MTOR is 
like the circuit breaker in a factory: When it’s activated, the cell 
grows and divides, consuming nutrients and producing proteins. When mTOR
 is turned down, the “factory” switches into more of a conservation 
mode, as the cell cleans house and recycles old proteins via a process 
called autophagy. One reason caloric restriction extends life span in 
animals, researchers believe, is because it slows down this mTOR pathway
 and cranks up autophagy. Rapamycin does the same thing, only without 
the gnawing hunger.
“Really
 what rapamycin is doing is tapping into the body’s systems for dealing 
with reduced nutrition,” says Brian Kennedy, chief executive officer of 
the Buck Institute for Research on Aging in Novato, Calif. “We’ve 
evolved over billions of years to be really good at that. When things 
are good, we’re going to grow and make babies. And when things are not 
so good, we go into a more stress-resistant mode, so we survive until 
the next hunt. And it just so happens that stress resistance is good for
 aging.”One of the most passionate advocates for rapamycin as an anti-aging drug is a Russian scientist named Mikhail Blagosklonny, who now works at the Roswell Park Cancer Institute in Buffalo. A native of St. Petersburg, he was working on cancer treatments in the early 2000s when he realized the same qualities that made rapamycin effective at slowing tumor growth might also help it slow the aging process. He became so convinced of rapamycin’s potential, and its safety, that he tried it himself. “Some people ask me, is it dangerous to take rapamycin?” Blagosklonny says. “It’s more dangerous to not take rapamycin than to overeat, smoke, and drive without belt, taken together.”
Many
 colleagues have regarded his advocacy as a bit over-the-top. When 
Blagosklonny submitted papers to major journals making these arguments, 
they were brutally rejected. “Sometimes, the reviewers would call me 
names,” he says. That started to change in 2009, when a large National 
Institutes of Health-funded study established that rapamycin and its 
derivatives helped mice live longer. The NIH scientists started mice on 
the drug at 20 months, or late middle age in mouse terms (mice typically
 live two to three years). Male mice on rapamycin lived 9 percent 
longer. The females’ life span was extended by 14 percent. This is 
roughly the equivalent of giving 60-year-old women a pill that would 
enable them to see their 95th birthday.
There’s
 one catch: Rapamycin suppresses the immune system (that’s why it’s 
effective with transplants). That fact, many scientists and physicians 
believe, is its Achilles’ heel as a drug to treat aging. Giving such a 
drug to older patients, whose immune systems are often already 
diminished, would make them vulnerable to life-threatening infections, 
defeating the purpose.
For believers like Blagosklonny, a breakthrough came on Christmas Eve 2014. That’s when a paper appeared in Science Translational Medicine, part of the Science
 family of journals. According to the study, conducted with volunteers 
in Australia and New Zealand, a derivative of rapamycin called 
everolimus had been shown to improve the immune response of elderly 
patients when administered in limited doses. It wasn’t the sort of thing
 that makes CNN, but in the world of scientists who work on human aging,
 it was big. “A watershed,” says Nir Barzilai, director of aging 
research at New York’s Albert Einstein College of Medicine.
“People
 have shown that rapamycin extends life span again and again and again. 
... I view it as the ultimate preventative medicine”
For
 the first time, the study showed, rapamycin appeared to enhance aspects
 of the immune response, boosting the efficacy of a flu vaccination in 
the study population, who were all 65 or older. “It seems to modulate 
the immune response, not suppress it,” says Barzilai. “It’s very 
exciting.” The study was noteworthy also because Novartis paid for it. 
For the most part, Big Pharma has shied away from aging, which 
conventional wisdom had deemed to be a quackery-ridden money pit. In 
2008, GlaxoSmithKline paid $720 million to buy Sirtris Pharmaceuticals, a
 biotech startup founded by Harvard professor David Sinclair that was 
developing drugs based on resveratrol, the antifungal compound found in 
the skins of red-wine grapes. Resveratrol received a tremendous amount 
of coverage in the media, including 60 Minutes, the New York Times,
 and Barbara Walters. It was said to be responsible for the “French 
paradox”: Although the French eat fatty foods, they remain healthy. A 
highly publicized Nature paper had shown that mice on a 
high-fat diet had lived longer with resveratrol. After the study 
appeared, sales of resveratrol supplements rocketed from basically zero 
to about $100 million a year. But the drugs all flopped in human trials,
 and in 2013 GSK shuttered its Sirtris division and fired all but a 
handful of staffers.
“The 
difference between rapamycin and resveratrol is that rapamycin really 
works as advertised and resveratrol doesn’t,” says the University of 
Washington’s Kaeberlein. “If you look at the data, you have to agree.” 
Kaeberlein, who went to graduate school with Sinclair at MIT, was an 
early critic of resveratrol, which he points out has actually never 
extended life span or otherwise slowed aging in normal mice—it appeared 
to work only in fat mice.
Rapamycin
 has been found to reduce age-related bone loss, reverse cardiac aging, 
and reduce chronic inflammation in mice. It’s even been shown to reverse
 Alzheimer’s disease in them. The Novartis study was the first to 
examine rapamycin’s effect on aging-related parameters in healthy older 
people. “It’s a landmark study,” says the Buck Institute’s Kennedy. 
“It’s the kind of study we need more of.”
That doesn’t mean 
everyone should be asking their doctors for a prescription to an mTOR 
inhibitor. Critics say it may be too risky for people who are otherwise 
fine. Besides the possibility of immune suppression, rapamycin’s side 
effects can include canker sores and impaired wound healing. “Rapamycin 
works on pathways that are too fundamental to normal cellular function 
to be used as a drug in healthy people until we have much more safety 
data,” says Valter Longo, a professor at the University of Southern 
California who discovered key pathways related to TOR. He points out 
that periodic fasting also shuts down the same pathways, without the 
side effects.The Novartis researchers tried to get around the immune-suppression side effect by giving the drug in very low doses and for a defined period. They found its benefits persisted long after the drug was discontinued. But the Novartis study is far from definitive on the issue, says Janko Nikolich-Zugich, chair of the department of immunobiology at the University of Arizona and co-director of the Arizona Center on Aging.
The 
study measured response to a vaccine, not to an infectious agent. 
Nikolich-Zugich fears that rapamycin would stop immune cells from 
multiplying quickly enough to fight off an army of invading pathogens. 
“I don’t think this in any way, shape, or form settles concerns about 
what mTOR inhibitors would do in cases of infection,” he says.
An
 innovative clinical trial set to begin in March may resolve some of 
these issues. Kaeberlein and his University of Washington colleague 
Daniel Promislow plan to test the drug in small doses in middle-aged pet
 dogs. Rather than looking at life span, which would take years, they 
will look for signs that the drug is affecting key aging-related 
parameters, such as arterial stiffness and cardiac function. If 
successful, rapamycin and its derivatives could end up as the first 
anti-aging drug—for dogs. Kaeberlein wouldn’t mind: “I love my dogs,” he
 says. “If there’s anything we can do to make them live longer, 
healthier lives, we have to do it. I feel like I personally have to do 
this.”
Rapamycin isn’t the only widely used medication that’s turning out to have possible anti-aging properties. Millions of diabetics take a drug called metformin, which has been around for decades. Like rapamycin, metformin extended the life of federally funded mice in a clinical trial. And there is evidence that it might do the same for people. Diabetes typically shaves about five years off a person’s life. But a large retrospective analysis found that diabetics on metformin had a 15 percent lower mortality rate than nondiabetic patients in the same doctors’ offices. “To me that suggests that it’s actually targeting aging,” says Kennedy.
“I remain skeptical that there will be one magic bullet,” says Novartis’s Fishman. But the 2014 study “is a good proof-of-concept”
The problem they’ll all face, though, is the same one that tripped up GSK: The FDA is unlikely to approve any drug intended to “treat” aging, because aging is not considered a disease. Another obstacle is the high safety standards required of any drug that would, in effect, be used to treat healthy people. “It would have to have fewer side effects than aspirin,” says Randy Strong, a pharmacologist at the University of Texas Health Science Center at San Antonio who worked on the 2009 NIH study.
This
 may explain why Novartis is taking an incremental approach with 
therapies aimed at specific conditions, says Dr. Mark Fishman, head of 
the Novartis Institutes for BioMedical Research in Cambridge, Mass., and
 a member of the company’s executive committee. “We’re therapeutically 
oriented, rather than looking for the pill that will make everybody live
 to 120,” he says.
The 
company’s age-related drug pipeline includes a novel drug aimed at 
treating heart failure, which the European Union recently fast-tracked 
for approval. Another, bimagrumab, is meant to reverse muscle loss. 
Designated a “breakthrough” by the FDA, it’s soon set to enter Phase III
 clinical trials for a rare condition called sporadic inclusion body 
myositis, but it could have wider application for muscle wasting and 
frailty in older people. “This whole frailty business is right up there 
with Alzheimer’s as a cause of incapacitation and sadness for the 
elderly,” Fishman says.
Also 
in the works are a drug that could potentially restore cartilage in 
aging joints and, most interestingly, a radical gene therapy meant to 
reverse the loss of “hair cells” in the ear canal that are crucial for 
good hearing, but which are knocked out by things like antibiotics, 
chemotherapy, and “too much Lady Gaga,” Fishman says.
He’s cautious about the anti-aging potential of rapamycin, which the company sells under the Afinitor brand name for cancer treatments and as Zortress for transplants, with 2012 sales of just more than $1 billion. (Pfizer, which purchased Wyeth in 2009, also sells a version under the brand name Rapamune.) “I remain skeptical that there will be one magic bullet,” Fishman says, “but [the 2014 study] is a good proof-of-concept, and it’s provocative enough that we’ll at least think of how and whether we should proceed.”
Blagosklonny isn’t so measured or patient. In his view, rapamycin has been approved for use for more than 15 years, with no serious problems reported. “I have read all papers about side effects,” he says, “and there are less side effects than with aspirin.” When he took it, he says, it made him feel better, “like with exercising.”
Novartis strongly discourages such off-label use. In an e-mail, spokeswoman Mariellen Gallagher wrote: “It is far too early to tell whether low-dose rapamycin will lengthen human life span. A favorable risk/benefit ratio needs to be demonstrated in clinic trials to be sure that mTOR inhibitors such as rapamycin have acceptable safety and efficacy in aging-related conditions in humans.”
In any case, one imagines Sehgal would be proud. After he was diagnosed with cancer in 1998, his son Ajai says, Sehgal began taking rapamycin, too—despite the drug not having been approved for anything yet. He had a hunch that it might help slow the spread of his cancer, which had metastasized to his liver and other organs. His doctors gave him two years to live, but he survived for much longer, as the tumors appeared to go dormant. The only side effect he suffered from was canker sores, a relatively small price to pay.
But in 2003, after five years, Sehgal, age 70, decided to stop taking the drug. Otherwise, he told his wife, he’d never know whether it was really holding back his cancer. The tumors came back quickly, and he died within months, says Ajai. “On his deathbed, he said to me, ‘The stupidest thing I’ve ever done is stop taking the drug.’ ”
(Corrects the caption for Mark Fishman and his role on Novartis's executive committee.)
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