Treating Baldness is "Not Like Growing Grass"

Treating Baldness is "Not Like Growing Grass"

By Rose Eveleth

Date: June 8, 2012
Source: scientificamerican.com

Progress may seem slow, but new treatments for hair loss are underway

Plain Grass lawn

More than 40 percent of men in the U.S. will show signs of male-pattern baldness sometime between the ages of 18 and 49. But studies looking at the genomes of this group of men have failed to turn up a genetic cause, which makes a true cure seem an unlikely prospect. 

Treatments for male-pattern baldness, also known as androgenic alopecia, may be forthcoming, however. Recent work is homing in on three types, including one that was reported in March in the journal Science. In the new paper, George Cotsarelis of the University of Pennsylvania and his team found that a compound known as prostaglandin D2 (PD2) was elevated in the blood of men with male-pattern baldness. When they blocked PD2 receptors in mice, they ensured that the hair did not stop growing. Those blockers could be applied topically, Cotsarelis says.

He is also working on growing new hair. Researchers have noticed that if you wound a mouse, the animal generates new hair follicles as part of the healing process. The new follicles come from skin cells that turn into hair follicles through what is called the Wnt-mediated signaling pathway. It is the same pathway that helps you generate new hairs naturally as they fall out. Cotsarelis is working with a company to replicate that process.

A third approach, called follicular neogenesis, would allow doctors to remove, multiply and then reimplant the stem cells found inside a person’s hair follicles. So far, though, when researchers remove the stem cells and culture them, the cells appear to “forget” they were ever hair cells. Researchers are now attempting to figure out how to restore their “memory.”

As scientists continue to search for treatments to androgenic alopecia, they recommend patience. “People think of it like growing grass or something, but it’s nothing like that,” Cotsarelis says. “It’s like trying to treat cancer; it’s a complicated process.”

This article was published in print as "It's Not "Like Growing Grass"."

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Men And Balding: Why We May Be The Last Men To Go Bald

Men And Balding

Why We May Be The Last Men To Go Bald

By Jeremy Berger
Source: uk.askmen.com

Jeremy Berger is a writer living in New York.

"There has never been a clinical treatment specifically developed for hair loss that worked."

Balding is the hoverboard of medical research. If someone had told me in 1989 that, more than 20 years later, my Birdhouse deck wouldn't float, I'd have told the butthead to get lost. But here we are in 2012. Hoverboardless. Dinosaurs.

Worse: Men have been losing their hair for thousands of years, and the best science has done is smoke and mirrors, ointment and wigs. Perhaps it's what we deserve for all our vanity, preening and grooming while the promises of liberal democracy smolder. Maybe we should shave our heads and rebuild America. But the truth is even the most stoic guys struggle with hair loss when it sets in, and it'll happen to about 50% of us by middle age. Only a much smaller percentage -- as low as 7% -- will ever seek medical treatment.

Understanding why this is boils down to the fact that there hasn't been a single groundbreaking treatment that permanently stopped or turned back the clock on hair loss. In fact, there has never been a clinical treatment specifically developed for hair loss that worked.

The options from recent history: wearing a wig; using a topical solution or foam with minoxidil, like Rogaine (developed initially to treat high blood pressure); taking finasteride, which is in Propecia and Proscar (first used to treat an enlarged prostate); or getting hair transplants. Each of these works in a piecemeal way, but they're all problematic. Wigs are a bit silly. Rogaine and Propecia have mixed results and must be used every day, for life. Transplants are limited by the amount of donor hair from the crown and back of the neck. None of them will bring back the flowing locks of your teenage years.

Some scientists and doctors think that could change in the next 10 years. Is it for real this time?

The best defense is a good offense

In recent years the theme of the balding conversation has changed from “maintenance” and “prevention” to actual regrowth. The reason? A better understanding of hair biology, including new knowledge of how cells communicate with the hair follicle. A study led by George Cotsarelis, M.D., chair of the Department of Dermatology at the University of Pennsylvania School of Medicine, that was published last year in the Journal of Clinical Investigation found that a bald scalp and one with hair both have the same number of stem cells, but in the bald scalp, the stems cells are sort of chilling out, just sitting there instead of going to work repairing and replenishing hair follicles and fibers. “However, the fact that there are normal numbers of stem cells in a bald scalp gives us hope for reactivating those stem cells,” Cotsarelis said in a news release issued by Penn Medicine. Get the stem cells working again and the hair comes back.

New Biotech: Follica, Histogen, Replicel

Cotsarelis declined to be interviewed for this story, but he's been hard at work as co-founder and member of the scientific advisory board of Follica, a privately held biotech company that has an exclusive license from Penn Medicine to develop technology based on the JCI study and another from 2007, which showed that mice with skin wounds regrew hair at the injured site in a process that mimicked embryonic development. This means that activated stem cells can grow new hair follicles. Little else is known of Follica's forthcoming balding treatment, except that it will likely include a drug compound and some sort of wounding of the skin akin to what went down with the mice.

Follica isn't the only biotech company trying to find a cure for hair loss and stake a claim in the multibillion dollar market for treatment, one that could conceivably balloon if a better treatment existed. San Diego-based Histogen, a privately held company headed by Gail Naughton, Ph.D., an expert in tissue engineering, also views Dr. Cotsarelis' work (along with studies at Rockefeller University by Elaine Fuchs and University of Southern California by Cheng-Ming Chuong) as the foundation of current biotech progress in hair restoration.

“Our approach is to take cells that are normally found in the scalp and grow them under embryonic conditions of very low oxygen and suspension culture to trick the cells into thinking they're back in the embryonic environment,” Naughton said.

“Within a couple of days they start acting like multipotent stems cells and secreting the growth factors that are necessary to stimulate stem cells in the body, including stem cells of the human hair follicle. We've basically learned how to manufacture a complex physiological group of growth factors that are normally responsible for stimulating stem cells to create new hairs. We simply mimic nature by figuring out how to make what the body makes to grow a new hair.”

Those growth factors, chemical signals produced by cells that induce more cell growth and maturation or differentiation, are what go into Histogen's Hair Stimulating Complex (HSC), an injectible liquid formula currently in clinical trials in Manila, Philippines.

Naughton believes she and her team have identified the four growth factors that are most important for the cycling of a hair follicle and for stimulating growth: Follistatin, Noggin (seriously), Vascular endothelial growth factor (VEGF), and Keratinocyte growth factor (KGF). So far, according to Histogen, patients have had statistically significant hair growth (including increases in hair count, hair thickness and hair density) at 12 weeks and at one year. Histogen aims to have a product on the market in Asia in 2015 and in the U.S. a year later. The actual procedure involves a one- or two-time set of injections in the scalp with a very fine 32-gauge needle, taking only several minutes rather than the hours required for a hair transplant.

"What we know for sure about the future is that there will be more robots."

Vancouver-based RepliCel is also working on an injectible treatment. Scientists there are banking on the dermal sheath cup cell, which they isolate from the root of the patient's hair follicle. That cell goes into a growth medium where it multiplies into the millions before being injected back into the patient's scalp and going to work growing new follicles and rejuvenating existing ones. “We believe that the dermal sheath cup cells are the progenitor cells that are necessary to instruct the rest of the cell population to form a follicle and to form a hair fiber,” David Hall, RepliCel CEO, said. “In layman's terms, we're doing a cellular transplant as opposed to a follicular transplant.”

RepliCel's phase one clinical trial is underway in Tbilisi, Georgia, and the company expects to have safety and efficacy data in early 2012. (Phase one of clinical trials primarily establishes the safety of the procedure. Phase 2 focuses on dosing and efficacy in a larger group of patients.) That means that a treatment in the U.S. would probably be available in the next five years.

Meanwhile, in New York...

In the meantime, hair transplant surgery has come a long way from obvious “plugs” -- large, clunky grafts -- to more precise implants in naturally occurring groups of 1-4 hairs called follicular units. Even RepliCel's Hall considers microtransplant surgery the gold standard for care in men. “In the hands of a gifted surgeon, it has a really good outcome,” he said. “The problem is that there are only so many gifted surgeons.”

The logic behind hair transplant surgery, aside from the obvious -- moving hair from once place to another -- is that the donor hair taken from the back of the head isn't sensitive to the androgen, or hormone, dihydrotestosterone (DHT). DHT is the culprit in male-patterned baldness that stops the follicle from cycling normally. (To the extent that Propecia works, it does so by blocking DHT.) In theory, a successful hair transplant should be relatively permanent. The other problem is that there are only so many hairs.

In the U.S. there are two new developments that could potentially improve the quality and availability of hair transplant surgery, which according to the American Society of Plastic Surgeons was the fifth most common cosmetic surgical procedure among men in 2010, behind nose reshaping, eyelid surgery, liposuction, and breast reduction.

One of these developments is being tested at the offices of Amiya Prasad, M.D., a cosmetic surgeon in New York City. Gary Hitzig, M.D., Medical Director of Prasad Cosmetic Surgery Hair Restoration Division, is banking on the same university studies cited by the biotech companies we interviewed. But instead of coming up with a proprietary injection -- like Histogen's HSC or RepliCel's dermal sheath cup cells -- he has sidestepped the research and FDA approval process by using ACell MatriStem, a product derived from pig bladder that has already been cleared by the FDA and is commonly used in regenerative medicine (including by Prasad in the other areas of his practice).

ACell MatriStem has been in the mainstream press for regenerating a woman's severed fingertip, healing a toddler's severed thumb and for its use in healing soldiers with significant battle wounds. It's made of collagen and other growth factors; when applied to wounds, it provides a sort of scaffolding for healing and simultaneously activates nearby adult stem cells to rebuild tissue.

Hitzig has experimented with several applications of ACell: Using it to accelerate the healing process and prevent scarring where donor hair was extracted, dipping hairs in it before they were transplanted into the top of the scalp, as an injection in non-transplant patients, and as an injection combined with platelet-rich plasma (PRP), blood plasma jacked up with even more growth factors than the ACell alone.

“It's amazing stuff,” he said. “We're at the stage now where I can take people who weren't candidates for transplants and we can go ahead and do them. We have a way of healing the area instead of scarring. And we have a way of getting a better result by multiplication of hairs growing on top.” He's especially excited about the injection, which he sees and as a way to slow down or stop hair loss.

“I equate it to a flu shot,” Hitzig said. “It may not stop you from getting the flu, but it sure as heck helps. We haven't had anything else like this.”

It's not a radically different concept than what the biotech companies are exploring: Create a nutrient- and growth-factor-rich environment to save dying hair follicles and grow new ones. The one problem is that Hitzig hasn't yet conducted a controlled clinical trial to prove that patients have statistically significant results with the ACell and PRP injection.

Thus, robots

The other development, naturally, is a robot. It turns out that extracting an implanting follicular units successfully is difficult and time-consuming, a procedure too tricky for many transplant surgeons. Restoration Robotics, a privately held medical device company, aims to democratize the procedure. Its first product, ARTAS, uses an image-guided robotic arm to harvest hair from the back of the patient's head.

Mohan Bodduluri, Ph.D, the founder and CTO of Restoration Robotics, said that he expects to roll out a product that can do even more in five years. “Internally, we call that 'hair transplantation in a box," Bodduluri said. “The expectation is that the follicles would be harvested, they would be stored and be implanted -- all by the machine. The technicians may never have to handle the graft.”

ARTAS is currently being used at hair transplant facilities in New York, Los Angeles, Dallas, and Denver. It looks a bit like a cross between a massage chair and Optimus Prime. Like most hair transplants, the cost of a procedure with ARTAS costs $10,000 and up, depending on the number of grafts and the reputation of the surgeon.

The future: Hairy

What we know for sure about the future is that there will be more robots. What we sort of know is that there will be a brief period of time when people in Asia and the Caucuses are walking around with pompadours while we're still in recession (both kinds). And what we can only speculate about is that Chinese President Hu Jintao and Vice-President, Xi Jinping did not get such exceptional hair through genetics alone. Somebody got his hands in the cell transplant injection jar.

Prasad said something interesting when I spoke to him about hair transplants and his work with Hitzig: “Hair transplant surgeons, kind of like chefs who cook chili, talk about how the other guys are not as good as I am because I do this that and the other thing. When you get down to it, no matter what doctor is doing the work, the quality of the transplant has an upper limit. It's a strategy to frame your face, create the illusion of more hair than you think someone has.”

He's confident that ACell will be a breakthrough, but his comments have broader implications: chili cooks are a pain in the ass. Also, framing the face is about more than just about the number of follicles in a scalp. It's about how we see ourselves and whether we really can, and want to, reverse-engineer the building blocks of nature for cosmetic purposes. Whether it's better to live generally within the bounds of nature or to live with an illusion of youth.

Common procedures are becoming less invasive and less costly. Botox was the most popular minimally invasive cosmetic procedure for men in 2010, up 10% over the previous year. There's a very good chance that we're less than 10 years away from a similarly quick and painless injectible treatment to stop or reverse hair loss.

When it happens, when we decide to use it, make no mistake: The treatment may go under the radar, but everything we do frames the face.

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The New Science of Hair Growth

The New Science of Hair Growth

Robot folliculr surgeons, invisible micrografts, in vitro hair cloning . . . scientists have a wider array of weapons than ever before in the war on baldness. Many believe we're finally on the verge of banishing it forever 

By: Michael Behar
Source: menshealth.com

Training Hair Cells to Grow

Nude mice are the foot soldiers for the war on balding. These dainty pink-hued rodents have been bred or genetically altered to remain hairless throughout their lives. They can be ordered by the mischief-load from medical suppliers and endure poking and prodding and other unspeakable horrors for the sake of balding men everywhere.

In Philadelphia, Ken Washenik, M.D., Ph.D., executive vice president of scientific and medical development for Aderans Research Institute and a clinical assistant professor of dermatology at New York University's Langone Medical Center, shows me slides of nude mice on his laptop. They have undergone a new type of hair-cloning procedure that Dr. Washenik has been developing for Aderans. The company, which has its headquarters in Tokyo, is the world's largest manufacturer of wigs. It also owns Bosley, which operates 88 hair-transplant clinics in North America.

When I arrive at Aderans, Dr. Washenik hastily ushers me past several labs, perhaps wary I might glimpse some sort of trade secret, and into an empty conference room. What he does reveal is that his approach to hair cloning (he calls it follicular neogenesis) doesn't rely solely on dermal papillae. "We are using a two-cell construct, growing not just dermal papillae, but also another type of cell from the follicle," he explains.

As the thinking goes, disparate cell types already communicate with one another in the follicle to regenerate hair. Dr. Washenik believes that if he can re-create that environment in the lab, cultured cells won't get dementia and forget how to make hair. "The different cells in the follicle are smarter than we are," Dr. Washenik says. "They already know they are supposed to be hairy. In 8 days, we grew a ball of hair that never existed before on the back of a mouse."

Dr. Washenik clicks an image file on his computer: The photo shows what looks like Piglet with a sable Mohawk. But there is a caveat: "These were hair cells from a mouse that were injected into a mouse. When researchers injected human cells into a mouse, they didn't get the same results."

This disappointed Dr. Washenik and other researchers, because unlike other organs, follicles are supposed to be immune privileged: When transplanted across or between species, they're expected to grow normally, without being rejected or provoking infection. He hopes to have better luck in clinical trials, when he will transplant human cells into humans. Aderans is in the second phase of a human trial, which is expected to be completed by the end of the year.

The company is pouring serious cash (Dr. Washenik won't say how much) into its hair-cloning effort. Dr. Washenik is also intrigued by other researchers who are pursuing another pathway. They're cultivating in vitro microscopic hairs, or "proto-hairs," as Dr. Washenik dubs them. "These are early follicular structures that you can place in the scalp with the same technology that's used for a hair transplant," he says. "The big hurdle so far is getting the cells to multiply to make enough hair. Once we culture them, they sometimes die or de-differentiate."

But Dr. Washenik remains confident. "The sooner we figure this out, the better," he says. "So many people are waiting for this technology. I know that with every medical advance, the first one to market becomes the leader, and everyone else plays catch-up." Like many of the scientists I meet, his passion for a cure is personal. "I started going bald at 25," he says, tussling his hair to flaunt his 2,200-graft transplant. "While I was working on my Ph.D., I was mixing up homemade minoxidil [the active ingredient in Rogaine] in my lab."

A few blocks away is a start-up called Follica. One of its cofounders, George Cotsarelis, M.D., is a cutaneous biologist and associate professor of dermatology at the University of Pennsylvania. In 1990, Dr. Cotsarelis was investigating the biological mechanisms of skin regeneration. "I was studying stem cells and found a population of them in the hair follicle, in a strange area called 'the bulge,'" he tells me when I stop by his office at U. Penn's School of Medicine. "We didn't know the function of the area, and we almost blew it off."

From then on, Dr. Cotsarelis started paying more attention to hair follicles. After a series of more recent experiments on mice, he made two important discoveries. First, he found that bulge cells aid in the formation of new hair follicles, suggesting that these cells influence hair growth during embryonic development, when we were bobbing around in the womb. He also learned that, throughout our lives, these same stem cells awaken to mend minor cuts and burns, as well as deeper wounds in the skin. What baffled Dr. Cotsarelis is why, if a healing wound is populated with bulge stem cells, new follicles don't form. The answer would at least explain why hair doesn't grow from scars.

Dr. Cotsarelis conducted further studies designed to reveal what kinds of molecular compounds (e.g., hormones and proteins) are present during hair-follicle development in mice embryos and are also present in adult mice. A major one, which he wrote about in a 2007 Nature article, was something called Wnt (pronounced wint), a network of proteins first identified in fruit flies.

Curious, Dr. Cotsarelis applied Wnt to small lesions purposely cut into nude mice (such gracious, noble critters). To his shock, follicles formed and sprouted hair. So if a person is bald, the obvious strategy would seem to be to douse his scalp with Wnt and wait for hair to grow. "The problem is that Wnt is involved in a lot of other things, one of which is skin cancer," Dr. Cotsarelis says. "It's very tricky business."

The idea behind Follica is to develop a procedure in which a surgeon would lightly wound the scalp—something akin to microdermabrasion, an antiaging treatment—to disrupt the skin and then apply a compound that would influence hair development in the area. This would trick the cells into reverting to an embryonic state, one in which they are genetically pre-programmed to make hair rather than simply repair skin, as they're predisposed to do after we're born. "Just when cells are deciding, 'Do I make a hair follicle? Or do I make an epidermis?' we can influence them with a protein to go down a hair-follicle pathway."

Testing the Science on Humans

My hair started thinning when I was 32. I'm now 40, and my shedding has eased up. Dr. Harris informs me I have plenty left for a follicular unit transplant. But after watching Scott's procedure, I'm a little freaked out. Yet, all the specialists I speak with urge anyone dealing with hair loss to act fast, because once the hairs are gone, they're gone for good.

"Absolutely no one concerned about hair loss should wait," Dr. Washenik says. He started taking Propecia when he was in his thirties (he's now 50), and he uses Rogaine religiously. He is a big advocate of drug therapies, and readily champions surgical options such as follicular unit grafting.

Dr. Washenik examines my scalp and announces, "Rogaine is made for you. You're not bald; your hairs are just miniaturized." I'm a chemical-phobe, so I'd rather save my dough and wait for a viable hair-cloning procedure, which many of the experts I talked to claim is less than 5 years away.

Intercytex, a public company based in London, may be closest to a marketable product, says Jerry Cooley, M.D., a transplant surgeon who has been consulting for the firm since 2001. Nobody directly employed by Intercytex would speak to me for this story. "We do not feel that exposure of our research is helpful," wrote Jeff Teumer, Intercytex's director of research, in a curt e-mail. But Dr. Cooley, who works closely with Teumer, tells me that Intercytex scientists have successfully grown large batches of cloned proto-hairs similar to those that other researchers have been struggling to keep alive.

What's more, in animal experiments, the Intercytex team has observed cloned hair follicles growing hair again after the original hairs were plucked. This suggests that their cloned follicles cycle through the entire life span of hair—three phases known as anagen (growth), catagen (transitional), and telogen (resting)—something no other researchers have been able to do.

A key to the team's success has been growing proto-hairs in a special medium, licensed from a Japanese inventor, which contains cultured skin cells known as keratinocytes. "I'm very excited about this technology," Dr. Cooley says. "It's not a matter of if, it's a matter of when."

Bessam Farjo, M.D., a hair-restoration surgeon contracted by Intercytex to run its ongoing clinical trials, says, "All I can tell you is that we've grown a significant number of hairs on animals through this technique." It sounds encouraging, and Dr. Farjo expects to complete clinical trials this year.

Hair cloning will be pricey initially, so early adopters may be men who are not only wealthy, but also desperate because they don't have enough hair left to do a follicular unit transplant. Cloning could also be ideal for younger men who aren't good candidates for follicular grafting. "Younger guys aren't suitable for current surgical techniques because we don't know how much hair they are going to lose," Dr. Farjo says.

Imagine if the receded hairline of a 25-year-old male were replaced with a follicular unit transplant. If the rest of his hair were to fall out—and going bald at an early age generally means it will—he wouldn't have enough hair to complete a second or third follicular unit transplant, so he'd end up with a solitary plume sprouting from his forehead. "It would look like unfinished business, which is why we typically avoid working on young guys," Dr. Farjo says. "But if I know I'll never run out of hair, thanks to the new cell therapy, I can treat anyone."

Nobody is sure how the actual cloning process will be implemented. Most surgeons speculate that they'll use boring tools similar to the existing ones used for harvesting follicular units. The follicular units will be sent to centralized labs, where industrial incubators will mass-produce millions of follicle cells for a relatively low cost.

Another question is how will the cloned cells be transplanted? Instead of transplanting follicular units, your surgeon may inject cloned cells into micro-incisions, or he may implant lab-grown hair follicles. It could be fast, clean, and painless. Or it might entail something closer to Dr. Cotsarelis's method at Follica. At Intercytex, technicians are tinkering with sundry techniques. "We're experimenting with varying the number of cells in each injection, and whether we have to inject the cells into the skin as it is, or if we have to pre-stimulate the skin," Dr. Farjo says.

Whatever the outcome, choices will abound. In the future, hair cloning will coexist alongside follicular unit transplants, drug therapies, and emerging technologies still incubating in the labs. For his part, Dr. Harris is also part of a team designing the world's first follicular extraction robot: It will fully automate the procedure, making it magnitudes faster and less expensive.

While Scott was being prepped for surgery, Dr. Harris took me into his office to show me a photo of the $25 million speed surgeon (the actual machine was locked in a storage closet a few floors above us). At about 6 feet tall with a fixed base and a mechanical arm with multiple joints, it resembles one of those space-age automatons you might see on a vehicle assembly line at a Toyota plant. Dr. Harris has already tested it on a couple of willing volunteers (with no alarming mishaps) and is preparing to apply for FDA approval under the name Restoration Robotics.

"We think the robot might be able to extract a thousand grafts an hour," Dr. Harris says. "That's more than triple what can be done by hand. This will broaden the market so that more people can afford the procedure. There may be a time soon when hair-transplant surgery will be available to everyone."

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New cause for male pattern baldness discovered: Is cure next?

New cause for male pattern baldness discovered: Is cure next?

By Michelle Castillo / CBS News/ March 21, 2012, 6:24 PM
(Source: cbsnews.com)

(CBS News) Men who lament the fact that they no longer have hair on their head may have some good news. Researchers have discovered a new potential cause that may help them get to the root of male pattern baldness.

A study published in the March 21 issue of Science Translational Medicine, found men who had a high level of a protein called prostaglandin D2 on their scalps were more likely to be bald. This protein and others like it have been known to block hair growth.

Male pattern baldness is the most common type of hair loss for men, the National Institute of Health said. According to WebMD, male pattern baldness occurs in 80 percent of men under 70. Symptoms include a thinning of hair at the hairline, eventually creating a U-shaped or horseshoe pattern of hair on both sides of the head. While treatment is not necessary, side effects including psychological stress and loss of self-esteem due to change in appearance can be experienced.

BBC News reports that the next step for the researchers is to find a treatment that targets the gene that triggers prostaglandin D2 protein.

Study author Dr. George Cotsarelis, a hair and scalp researcher at the University of Pennsylvania told BBC News, "The next step would be to screen for compounds that affect this receptor and to also find out whether blocking that receptor would reverse balding or just prevent balding - a question that would take a while to figure out."

Cotsarelis told The Daily Mail the treatment could possibly be available within five years.

"The nice thing about dermatology and hair loss in general is that you can take compounds that maybe are being used as a pill and put them in a topical formulation. When you apply this to the scalp... you would allow hair to grow," he said. "We could imagine using this compound topically would be a great treatment."

Right now, the only treatments for male pattern baldness are minoxidil, commonly known as Rogaine, and Propecia, a prescription pill originally developed to treat enlarged prostate glands, WebMD reported. Other ways to hide baldness, include hair pieces or hair transplants.

Any news about what causes male pattern baldness is good news for people with this affliction. While hereditary factors and sex hormones have been linked, no direct cause has been determined. Often times the "cures" have been discovered by chance. For example, Rogaine was initially a treatment for high blood pressure, according to WebMD.

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