Setipiprant: What It Is & Can It Treat Pattern Hair Loss?

Many pharmaceutical companies are working on a drug or developing technologies that can treat pattern baldness. In their efforts, they developed the oral medication setipiprant. Despite the buzz that it created, the drug itself turned out to be underwhelming. 

There’s some anecdotal evidence of it working for hair loss, but for many others, it hasn’t benefitted them in any way. Regardless, it is a good idea to take a look at the drug itself and the reason(s) why it didn’t work. 

What Is Setipiprant?

A derivative of tetrahydropyridoindole, setipiprant is an investigational drug that was developed for allergic rhinitis and asthma. The clinical trials for this drug were discontinued because it did not have a competitive advantage over the other drugs available in the market. 

However, the clinical trials of the drug started back again, but this time as a prostaglandin receptor antagonist – the PGD2 receptor, more specifically. There are different types of prostaglandins, and surprisingly, they work antagonistically. There’s a type that’s been shown to promote hair growth, while there’s another that actually stops it. 

One study published in Science Translational Medicine found that PGD2 can come in the way of hair growth and recommended investigating its pathway as a potential treatment for pattern hair loss. More PGD2 was found in the scalps of people who were balding. 

Therefore, if setipiprant could inhibit the prostaglandin receptors from activating, it could potentially treat androgenetic alopecia. Eventually, this led to Kythera Biopharmaceuticals, which was working on the drug, being acquired by Allergen in a $2.1 billion deal. 

How Does It Work?

It was hypothesized that PGD2 receptors were a part of the events that led to the miniaturization of hair follicles. So, if it was intercepted (setipiprant binding to the receptors instead), it could solve the problem. 

The idea of it is somewhat similar to how finasteride works, which stops the 5α-reductase enzyme from converting testosterone to dihydrotestosterone. This is what’s primarily responsible for causing pattern baldness. As promising as this may sound, setipiprant clinical trials did not yield favourable results. 

What Were the Results of Setipiprant Clinical Trials?

The first clinical study on the effect of this drug on hair growth was done on men who had androgenetic alopecia. They were between the ages of 18 and 49 and were in stages 3-5 of the Norwood-Hamilton Scale. The participants were given a 1000mg tablet of setipiprant twice a day (2000mg total) for 24 weeks. It was randomized, placebo-controlled, and the results were assessed at weeks 4, 8, 16, 24, and 32. 

While no adverse effects of the drug were reported, it did not work. There was no “statistically significant” difference between the results of the placebo group and the setipiprant group. The researchers suggested that maybe higher doses of it were required. However, the setipiprant clinical trial results were disappointing overall. This study was sponsored by Allergen itself. 

What Are the Problems With Setipiprant for Hair Loss?

Other than the fact that it might just not work, there are other problems with the use of this drug. The biggest problem of all is that it’s prohibitively expensive. Those who are taking them report costs in thousands of dollars. It can be twice or thrice more expensive than a hair transplant. 

Although the study mentioned above doesn’t report any adverse effects of the drug, some people have reported experiencing sleep difficulties after taking setipiprant. Since the drug inhibits the activation of prostaglandin receptors, it may affect other areas of the body. Therefore, you need to consult with your dermatologist before considering taking this medicine. Otherwise, it can be a colossal waste of your resources. 

Alternatives To Setipiprant For Hair Loss Treatment 

It is important to note that before starting treatment, you should get a diagnosis for your hair loss from a medical professional. Depending on the reason behind it, your doctor will recommend treatment accordingly. The following are more commonly recommended solutions for hair loss. 

Minoxidil & Finasteride 

These drugs are usually recommended for hair loss. However, with minoxidil, there’s the common problem of skin irritation. In addition, it can cause the growth of unwanted facial hair. Those who take finasteride report sexual dysfunction, which is why there are many people who want other treatment alternatives. 


Also known as Aldactone, it stops the androgens from binding to their receptors, which helps with pattern hair loss. However, keep in mind that this drug is not prescribed to males. It also has many side effects, and it can take quite a long time for you to see any results. 

PRP & Hair Transplant 

Usually, platelet-rich plasma therapy is recommended for patients who want to go hair transplant but can’t because they’re too young (less than 25). However, this therapy is also recommended in conjunction with a hair transplant to further improve its results. So far, a hair transplant is the only treatment that can permanently restore hair growth.

Concluding Remarks 

For many, many years, people have been trying to find a cure for pattern baldness. Although we’re advancing towards an era where that might be a possibility, so far, that’s not the case. There’s no supplement, device, or medication that can permanently restore hair growth. Hair transplantation surgery has been the only thing to accomplish that. 

Drugs like setipiprant are investigational, so there’s no evidence that it works. The clinical trial on it was also not successful. Moreover, it is extremely expensive and can have some side effects. One which is commonly reported is sleep disturbance. 

If you’re experiencing hair loss, it is important that you get yourself checked by a dermatologist. Your hair loss can occur due to many different reasons other than androgenetic alopecia. Once you have a diagnosis, you should consult your doctor about treatment options while weighing all their pros and cons. 

Reviewed and Approved by Trichologist Yaprak Yazan

Open chat
Hello would you like a free e-consult?
Hello would you like a free treatment plan and a price quote?

Tap the icon at the right bottom to make an enquiry.