It was reported earlier this month that Britain’s Prince William may be considering getting a hair transplant.
The Prince – like most men who find that a large part of their hair has gradually disappeared over the years – reportedly suffers from androgenic alopecia, and has been looking for a way to halt it for some time now.
Should the Prince decide to go ahead with a transplant, he would likely be advised to pursue a six-month course of medication beforehand, consisting of licensed drugs such as Aindeem, produced by the pharmaceutical company Actavis, and Rogaine, produced by Johnson & Johnson.
The FDA Approval Process
The U.S. Food & Drug Administration has a stringent process that all drugs and medical devices must pass before gaining approval.
Before a drug is approved for use by the FDA, there are three main areas which are considered:
- The target condition and available treatments
- Benefits and risks from clinical data
- Strategies for managing risks
There are four major steps in the process, which are 1) pre-clinical; 2) clinical; 3) NDA review; and 4) post-marketing.
The first step, pre-clinical, is all about discovery and screening. This is when the drug is developed, the drug is initially tested ex-vivo and on animals, and the manufacturers and sponsors submit the Investigational New Drug (IND) application.
During the clinical step is when more in-depth testing occurs. The drug is tested in three phases, which generally include:
Phase 1. A small (less than 100) group of healthy volunteers to test the safety of the drug, as well as how it is metabolized and excreted.
Phase 2. A larger (100s to 1000s) group of individuals are tested to determine the efficacy of the drug. These individuals are within the target group, so they suffer from the condition the drug aims to treat. These trials often involve a placebo or a comparative drug (known as a controlled trial).
Phase 3. The largest group of participants (in the thousands) as compared to the previous two phases. This focuses more on safety and efficacy, dosages, drug interactions, and how the drug may affect different populations.
It is after the three phases above are complete that the FDA will review the application submitted by the manufacturer. This will include the results of all studies.
If approved, the drug will move into the final stages which involve drug labeling and manufacturing facility inspection. Once the drug hits the market, the manufacturer or sponsor will then be required to submit periodic safety and efficacy data to the FDA for monitoring.
Rogaine (Minoxidil)
Minoxidil, first branded as Rogaine, is an over-the-counter topical medication developed to slow balding and promote regrowth.
The drug was first discovered to be effective in promoting hair growth in the late 1970s or early 1980s. At this time, minoxidil was an oral drug under the brand name Loniten. It was prescribed for the treatment of hypertension (high blood pressure).
As clinical studies began to note hair growth as a side effect of the drug, though, doctors began to prescribe it to their balding patients for off-label use as a hair loss treatment.
While the oral version of minoxidil had good results, the drug was soon developed into a topical medication. The drug, now known as Rogaine, was approved by the FDA in 1988.
How does minoxidil work?
According to the latest research, minoxidil has numerous pathways including (1):
- Induction of arteriolar vasodilation which stimulates microcirculation near the hair follicles
- Induction of vascular endothelial growth factor (VEGF) expression which increases vascularization around the hair follicles
- Activation of the prostaglandin-endoperoxide synthase one which stimulates hair growth
- Inhibition of androgen effects on the androgen-sensitive hair follicles
- Direct stimulation of the hair follicles by prolonging the duration of the anagen phase via the activation of the beta-catenin pathway
In short, minoxidil supports the hair follicle to promote hair growth via typical biochemical processes.
So how effective is minoxidil as a hair loss treatment?
One study on the topic suggests that 40% of patients who use 5% topical minoxidil to treat pattern baldness will see hair growth (2). This is further supported by a meta-analysis that showed “mean differences of 8.11 hairs/cm2 and 14.90 hairs/cm2 associated with the 2% and 5% minoxidil treatments, respectively, compared to the placebo group (3).”
How long can you expect it to take to see results?
Clinical response is noted to take three to six months and results typically peak at the one-year mark (4, 5).
For the most part, minoxidil is a safe topical treatment option for men and women with pattern balding. Its most common side effects are skin irritation, though these can often be mediated with the use of an alcohol-free minoxidil formulation (6).
Propecia (Finasteride)
For an oral hair loss treatment drug, look no further than Propecia.
Propecia is an oral drug that was originally developed as a treatment for Benign Prostatic Hyperplasia (BPH), a medical condition characterized by enlargement of the prostate gland. The drug’s active ingredient, finasteride, was soon discovered to have the effect of treating hair loss in patients with pattern balding.
How does Propecia work?
The drug is a known inhibitor of 5-alpha-reductase, the enzyme responsible for the conversion of testosterone to dihydrotestosterone (DHT) (7).
When it comes to male-pattern baldness, DHT plays a major role.
Whether you believe in the DHT Theory of Hair Loss or the Scalp Tension Theory of Hair Loss, then you’ll know DHT’s presence at the hair follicle can wreak havoc for those with a genetic predisposition to hair loss.
This is because those with androgenetic alopecia are sensitive to the androgen DHT. While it is supposed to act as an anti-inflammatory, it triggers inflammation and hair follicle miniaturization in men and women with pattern balding (8).
If the miniaturization is left untreated, then noticeable hair loss will occur. This results in the tell-tale pattern of balding along the hairline as seen in men.
So back to how Propecia can help.
As mentioned, Propecia inhibits the enzyme responsible for the production of DHT. With less DHT in the body, there is less DHT in the hair follicles. As such, Propecia treats the condition indirectly by removing one of the main triggers.
There are problems with this approach, however.
With a reduction of DHT, there is a potential for sexual side effects. This is because DHT is an androgen hormone responsible for secondary male characteristics.
Risks and Side Effects
Side effects may include loss of libido, inability to get or maintain an erection, inability or difficulty to achieve orgasm, and loss of ejaculatory volume (9). These symptoms may persist for as long as finasteride is in use and, in some cases, even after finasteride has been discontinued (10).
While finasteride use has been studied in women, there are significant risks associated with use (11). The drug may impede the development of a male fetus, so women of childbearing years are strongly urged against its use.
Hair Transplantation
Do keep in mind that a hair transplant isn’t a “cure” for hair loss. If you suffer from pattern baldness and you don’t treat the underlying cause, the hair loss will just happen again after the transplant.
NeoGraft
NeoGraft is a semi-automated hair transplant system. It automates the follicular extraction process which is performed during a Follicular Unit Extraction (FUE) hair transplant.
The FUE technique is considered the gold standard in hair transplant surgery. The procedure involves the extraction of individual hair follicles at the donor site so they can then be transplanted into the recipient site.
This is in contrast to Follicular Unit Transplantation (FUT) in which the follicles are extracted in strips.
With FUE, there is less scarring, fewer side effects, and more natural-looking results.
The main benefits of the NeoGraft system are increased accuracy and speed. While a manual FUE procedure can take
The NeoGraft system is cleared by the FDA.
ARTAS
A more advanced hair transplantation technique is ARTAS.
Just like NeoGraft, ARTAS is a technique for performing FUE hair transplantation. The difference is in how the procedure is carried out.
As mentioned above, NeoGraft is semi-automatic. The device is handheld, but it is still controlled by the surgeon. ARTAS, however, is fully automated. This technique utilizes a robotic arm to extract and transplant hair follicles.
The ARTAS device was approved by the FDA for hair transplantation in 2011.
Which Technique Is Best?
If both NeoGraft and ARTAS are approved by the FDA, how can you know which technique is right for you?
When it comes to the two procedures, they both offer less risk and more natural results than the traditional hair transplantation methods. While the robotic arm can be more precise, there are those individuals who prefer the hand of a surgeon.
But for many, the decision will come down to cost.
For those who can afford the cost, ARTAS can be a great choice. However, NeoGraft offers similar results with a lower price tag in most cases.
Low-Level Laser Therapy
Perhaps you’re not looking for such a “drastic” procedure as a hair transplant. In that case, you should consider Low-Level Laser Therapy (LLLT).
LLLT is a treatment that uses low-level lasers to stimulate the hair follicles. But what exactly does stimulate mean?
The speculated mechanism by which LLLT is thought to promote hair growth is by stimulating epidermal stem cells (12). It has been suggested that stimulation of the stem cells within the hair follicle’s bulge region leads to differentiation and proliferation.
In simplest terms, it promotes anagen phase hair growth through the proliferation of dermal papilla cells.
How effective is LLLT at treating hair loss?
An evidence review from 2016 considered numerous studies on LLLT and its effect on hair growth (13). The studies included in this review were 2 in vitro, 7 animal, and 12 clinical.
As the authors of the review concluded, “Based on this review on all the available evidence about effect of LLLT in alopecia, we found that the FDA-cleared LLLT devices are both safe and effective in patients with MPHL [Male Pattern Hair Loss] and FPHL [Female Pattern Hair Loss] who did not respond or were not tolerant to standard treatments.”
Low-level lasers have been used in dermatology for years. In 2007, however, they were approved for use in the treatment of hair loss.
There are various LLLT devices with FDA clearance. These devices can be caps, combs, or wands. With the increase in FDA cleared devices on the market, you can do LLLT in the comfort of your own home.
Risks and Side Effects
As the review study above highlighted, the side effects of using LLLT for hair loss were minimal. These included:
- Headache
- Skin pain and burning
- Itching
- Acne
- Redness
- Mild numbness
These side effects may lessen over time. If any of the above side effects become bothersome, discontinue the use of the LLLT device and consult with your physician.
If you are prone to growths or malignant tumors on the scalp, it is best to avoid the use of LLLT devices as low-level lasers may stimulate growth.
Future Treatment Possibilities
Due to its widespread nature, there is continuous research being done on genetic hair loss and its potential treatments. This means there is always a possibility for new drugs and procedures to be released in the near future.
What are some options that may be coming down the pipeline for 2024 and beyond?
Dutasteride
As with many potential hair loss drugs, dutasteride is already being prescribed by physicians for off-label use as a hair loss treatment. While the drug has yet to be FDA-approved for this use, it has been cleared for the treatment of prostate enlargement.
If that sounds similar to finasteride, it is because it is not too far off.
Dutasteride is a 5-alpha-reductase inhibitor.
Just like finasteride, dutasteride inhibits the enzyme 5-alpha-reductase which slows production of DHT. This results in lower DHT levels throughout the body.
Even though finasteride and dutasteride have the same mechanism, dutasteride is more effective at reducing DHT levels. Why? Because it targets all three types of 5-alpha-reductase, not just two like finasteride.
When it comes to converting testosterone to DHT, there are two types (or isozymes) that play a role: Type I and Type II (14). Finasteride inhibits just types II and III, while dutasteride inhibits all three isozymes (15).
This means dutasteride can further lower DHT levels by specifically targeting the isozymes involved in its production.
You may be wondering, does increased efficacy mean more or worsened side effects?
According to researchers, “Dutasteride seems to provide a better efficacy compared with finasteride in treating AGA. The two drugs appear to show similar rates of adverse reactions, especially in sexual dysfunction (16).”
JAK Inhibitors
When it comes to combatting hair loss, it is important to treat the root cause.
For those with androgenetic alopecia, the cause is a genetic predisposition to DHT sensitivity. This is now believed to be triggered by chronic scalp tension, though other theories exist (17).
Aside from AGA, however, another common cause of hair loss is alopecia areata which is believed to be caused by an overactive immune response (18). The body mistakes hair follicles as foreign invaders and attacks them. This results in balding patches throughout the scalp and, in extreme cases, loss of hair throughout the body (alopecia universalis).
It is this type of hair loss that JAK inhibitors may be able to treat.
Janus kinase, or JAK for short, is a group of enzymes including JAK1, JAK2, JAK3, and tyrosine kinase 2 (TYK2). These enzymes exist as receptors on the cell’s surface.
When an immune response is triggered, anti-inflammatory molecules known as cytokines bind to these cell receptors and activate JAK enzymes. This leads to the mobilization of host defenses, such as an increase in white blood cells.
While JAK enzymes perform an essential duty, they can also interfere with hair growth.
With the use of JAK inhibitors (also known as jakinibs), it may be possible to prevent hair loss such as alopecia areata.
There are currently two JAK inhibitors approved by the FDA.
Ruxolitinib (Jakafi) was approved in 2011 as an intervention drug for treating myelofibrosis, and Tofacitinib (Xeljanz) was approved in 2012 to treat patients with moderate to severe rheumatoid arthritis.
While JAK inhibitors have yet to be approved by the FDA for the treatment of alopecia areata, there are clinical trials underway (19).
While only speculative at this point, there is hope that JAK inhibitors can stimulate hair regrowth for sufferers of androgenetic alopecia, too. It may be possible through the stimulation of hair germ, follicular stem cells, and dermal papilla cells (20).
Stem Cells
Stem cell research is often controversial enough to make some people disavow it altogether. But what if stem cells taken from your own body could be used to repair damaged scalp tissues and even generate new hair follicles? This is the future of stem cell research for hair growth.
Stem cells are unspecialized. However, they can divide and replicate to either become 1) new stem cells; or 2) a different type of cell.
How might stem cell transplantation promote hair growth?
One major benefit thought to be attributed to stem cell transplant is the ability of the stem cells to repair damaged tissues in the area. But they may also be able to transform into Dermal Papilla Cells (DPCs) which are necessary for new hair growth (21). They can also be used to “grow” new follicles.
Now you may be wondering how stem cell transplantation is performed. There are two ways.
The first way involves the removal of stem cells from the patient’s body, typically from adipose (fat) tissue. The stem cells are separated from the fat and then injected directly into the patient’s scalp.
This procedure takes about three hours, and it is performed on an outpatient basis. The procedure is also authorized by the FDA as an Investigational New Drug Application (IND). While it is not widely available, there are hair loss specialists who currently perform this procedure.
The second way is similar to a standard hair transplant.
Using a punch biopsy, stem cells are extracted from the scalp of the patient. The stem cells are separated from the tissue of the biopsy using a centrifuge. Once separated, they are then used in a laboratory setting to grow new hair follicles. Once matured, the hair follicles are then transplanted back onto the scalp of the patient.
But what about side effects?
As of now, side effects seem minimal and include infection and bleeding at the site of extraction and transplant. These are common side effects of a hair transplant procedure.
Preliminary results are indeed promising. One study showed a 29 percent increase in hair density 23 weeks post stem cell transplant (22). With FDA approval pending, there is still further research to be done.
WAY-316606
The drug WAY-316606 was originally formulated for the treatment of osteoporosis, a condition that causes fragile bones and increases a person’s susceptibility to fractures (23).
The drug was soon found to have a beneficial effect on hair growth. As such, it is development and approval as a topical hair loss drug has been underway for the last few years.
Here is how it works.
WAY-316606 is an inhibitor of the Secreted Frizzled-Related Protein 1 (SFRP1).
The protein SFRP1 modulates the Wnt signaling pathways. These pathways, and more specifically the ‘canonical’ pathway, lead to the regulation of gene transcription, which is crucial when determining what role genes will play.
When it comes to hair growth, the Wnt signaling pathway ensures cell differentiation happens as it should.
As hair follicles and their accompanying hairs develop, a process known as cell differentiation occurs. This takes place in the Dermal Papilla (DP), which is essentially the base of the follicle.
During this process, proteins are produced and delivered to various parts of the follicle. However, overexpression of certain proteins, particularly SFRP1, can lead to quickened cycling and structural defects of the hair strand.
If left uninterrupted, this can lead to follicle miniaturization.
Using a SFRP1 inhibitor like WAY316606 slows the overexpression of SFRP1. The hair cycle is then able to proceed at a regulated pace which reduces telogen phase shedding and encourages more follicles to remain in the anagen phase.
There are concerns about what this drug could mean for cancer risk, as a drug that regulates the Wnt signaling pathway could seriously increase risks.
While a few trials have taken place, it is still too early to tell if WAY316606 will ever make its way to FDA approval (R, R).
Conclusion
The FDA approval process is long and strenuous. While there is certainly some bureaucratic
red tape that impacts the process, the overall stages and phases are in place to ensure the safety and efficacy of all patients.
There are currently only two FDA-approved medications for the treatment of hair loss, finasteride and minoxidil. However, there are also procedures, like NeoGraft and LLLT, that are also approved by the FDA for use in treating hair loss. Many future possibilities just may become a reality in the next few years.