Q: Why aren’t pharmaceutical companies all over this?
A: There’s no economic incentive. A single drug in clinical development generally costs around a billion dollars, from the very beginning to the end. A pharmaceutical company can only afford to spend that kind of money on trials of something it knows it can sell as a prescription drug, with a pretty high profit. The issue here is that you can’t sell something as a prescription drug unless the Federal Drug Administration recognizes that there’s an indication for it. And the FDA does not consider aging a disease, so it wouldn’t give regulatory approval to a prescription drug used to treat aging.
Q: But since rapamycin is already prescribed, wouldn’t clinical trials testing anti-aging benefits in humans be less expensive?
A: Somewhat, because we have a pretty good handle on its side effects—though not a great handle, because the research has been done on people who are extremely sick, transplant patients, not healthy people. So there would still be substantial costs and again, even if you had that money, you could never sell rapamycin as a prescription drug for aging.
Q: Why isn’t the nutraceutical industry doing the research?
A: The profit margin on supplements simply isn’t big enough to support the clinical research you’d have to do to prove that something works in humans. First off, there’s a tough scientific nut to crack. Nobody is going to fund a study that goes on for 50 years, to see whether a drug actually does extend human lifespan. So scientists need to develop “biomarkers” of aging, which basically indicate how fast a person is going downhill. If reliable biomarkers were developed, then you could do fairly short trials. It would be the same logic used when testing cholesterol drugs to prevent heart attacks: you don’t wait 20 years to see whether heart attacks are really averted—at this point you basically just see whether LDL cholesterol has been lowered, and say, “Okay, that’s our proxy for lower heart attack risk, the drug works.” You could do the same thing with the biomarkers of anti-aging if scientists had them.
Q: Are there any ideas about where to start looking?
A: Yes. The longest study on the effects of aging is the Baltimore longitudinal study, which has been going on for decades. A few years ago, they looked at the people who lived the longest, and one thing that jumped out in the research, so it might be correlated with a long healthy life, is low insulin levels. Insulin tends to rise as you get older, regardless of your diet, regardless of whether you’re prone to diabetes. But apparently people whose insulin stays very low, youthfully low, tend to live a long time. There’s a lot of other science that would suggest that indeed, low insulin is closely associated with slow aging. So one biomarker might be just to look at insulin levels over time among the people taking a drug that supposedly slows aging. If it keeps insulin levels down, that would be one indicator it works—though obviously you’d need more. Establishing reliable biomarkers would take a lot of research, and unfortunately right now that research isn’t being done. We need someone with very deep pockets, such as the U.S. National Institutes of Health, to step forward to sponsor it.
Q: How much is the U.S. government currently spending to research the biology of aging?
A: In recent years, the National Institute on Aging has spent about $200 million annually, which is about one-fifth of its budget. But much of that is spent on studies about specific diseases rather than on research about the fundamental study of aging. In contrast, the National Cancer Institute’s annual budget is about $5 billion.
Q: Why haven’t anti-aging researchers been more successful at marshalling resources?
A: In a nutshell, the world of medical science doesn’t recognize what’s happened in the research on gerontology. Partly it’s because the anti-aging field has historically been an area rich with snake oil and con artists, and partly it’s because aging is extraordinarily complicated—so much so that unlike diseases, many biologists felt that figuring out exactly what was driving it was a hopeless cause. To a large extent, that’s how the FDA and many physicians still think about anti-aging research. People just don’t know how far the science has come and how promising it is.
Q: How far away do you think we are from human studies on drugs like rapamycin?
A: It’s very hard to answer. If you could successfully lobby Congress for increased funding—not necessarily for clinical research but for the basic research on biomarkers, which you’d need first—I would think you could hope to be in clinical trials in 10 years. In the best of all possible worlds, I would not be surprised if within 20 years there were some pretty well-established agents on the market that could slow aging. Whether we’ll get there in that time frame is anybody’s guess. It all depends on the politics.
Q: Aside from the cost, why would politicians oppose anti-aging research?
A: There’s great concern that anti-aging drugs will lead to drooling, demented seniors littering the landscape. But the interventions known to reliably slow aging in animals don’t prolong a period of terminal decline. At worst, they merely postpone it.
Q: So as a society, we’d still have to pay for a senior who gets a disease, we’d just have to pay a few years later?
A: That may well be true. But isn’t that the whole point of medicine, to buy us more quality time?
