Breezula for Hair Loss: How It Works & Side Effects

Could the answer to male pattern baldness be a medication that’s currently approved for something else entirely? Enter Breezula^®, a possible treatment for androgenetic alopecia.

Breezula, which is manufactured by the Italian drug maker Cassiopea, is the brand name for a topical treatment whose generic version is clascoterone. 

It’s currently undergoing clinical trials for the treatment of hair loss and is not yet available to prescribe and purchase for this purpose. So far, evidence suggests it may be a game-changer when it comes to treating hair loss.

Below, we’ve explained how this new drug will reportedly work, whether Breezula hair loss results look promising, and potential side effects. We also garnered insight from one of our medical advisors, board-certified dermatologist Dr. Knox Beasley, MD.

Breezula (also known as CB‑03‑01, clascoterone) works by inhibiting the actions of androgens (male hormones), which can cause conditions like acne and hair loss. It’s a solution that’s meant to be applied twice daily.

Pharmaceutical company Cassiopea (owned by parent company Cosmo Pharmaceuticals) explains that the topical solution could treat androgenetic alopecia when applied to the scalp (more on the data to back that up in a moment).

For now, just know that Breezula, being studied in concentrations of 2.5%, 5%, and 7.5% is fairly far along in the testing process for hair. Some versions of it are already FDA-approved for other things.

You may even already know someone taking this medication for acne in another form since clascoterone goes by several names, including:

• Breezula

• Clascoterone

• Cortexolone 17α-propionate

• Winlevi

The active ingredient in Breezula is clascoterone, an antiandrogen medication sold under the name Winlevi cream, which is FDA-approved for acne vulgaris in adolescents and adults. And the goal is that it eventually gains FDA approval for hair loss under the brand name Breezula.

Can Breezula stop male pattern balding and regrow hair that’s already been lost?

Things look promising for conditions like androgenetic alopecia, or androgenic alopecia, which is the most common type of hair loss.

Male pattern hair loss is related to androgens, or male hormones, and one hormone specifically: dihydrotestosterone (DHT). 

Increased DHT activity and sensitivity to DHT are both associated with hair loss. When DHT binds to androgen receptors in hair follicles, it causes miniaturization of the follicles and, eventually, hair loss. 

According to Breezula’s makers, the drug is an antiandrogen, meaning it inhibits the ability of DHT to bind with androgen receptors in the scalp. This action reportedly reduces hair miniaturization, or hair thinning and loss. 

In this regard, there are some similarities to finasteride, an FDA-approved and widely accepted hair loss treatment. Both finasteride and Breezula target the effects of DHT, but they do so differently. Finasteride lowers overall DHT levels in the body by blocking its production through inhibiting an enzyme, while clascoterone works by preventing DHT from binding to androgen receptors.

Breezula completed all Phase II trials in 2021. Note that these results remain unpublished in peer‑reviewed journals.

Cosmo Pharma has documented the so-far positive results through a series of press releases on its website. This includes results of a study that lasted 12 months and involved 400 subjects in Germany. 

According to the press releases, male participants with mild to moderate androgenetic alopecia saw an increase in target hair counts and hair widths when using the 7.5% solution twice daily. Females participants under 30 using 5% clascoterone also reported notable results. The placebo group, on the other hand, saw a worsening of their hair loss. 

A pharmaceutical company’s own data is clearly not the same as independent study data. But two pivotal Phase III trials (SCALP1 & SCALP2) began in June 2023 across the U.S., Germany, Poland, and Georgia. 

Trials for Breezula are expected to conclude sometime in 2025, but potential US/EU approval may not occur until 2028 or 2029.

While a lot can happen in that timeframe, Breezula remains the only topical androgen receptor inhibitor in advanced trials for androgenetic alopecia in men.

Unfortunately, side effects of Breezula are not widely known yet. One 2020 study of the acne-fighting clascoterone solution found side effects to be generally mild.

But the European Medicines Agency (EMA) recently issued an opinion refusing marketing authorization for Winlevi (1% clascoterone cream) for acne in minors, citing concerns over hormonal suppression in teens, which could lead to “impaired growth and sexual maturation.” Cassiopea appealed the decision as of May 2025.

The fact is that there isn’t much published data on Breezula, and more is needed to provide further insight. Here’s what we can say so far about the potential for clascoterone hair loss safety and results. 

Efficacy: N/A. “This is unknown. Since there is so little data on this it's hard to give it a rating,” Dr. Knox tells us.

Side effects: ★★★★ “There is a version of this medication used to treat acne which has very few side effects, so it's likely that Breezula will be well tolerated as well,” says Dr. Knox.

Ease of use: ★★★★ “This will be a topical medication but the exact formula (cream, liquid, solution) and dosing (number of times needed to apply daily) are yet to be determined,” says Dr. Knox. 

The bottom line is that there’s not enough research available on Breezula to say much about its effectiveness just yet. 

“Until we have more published data on Breezula it's difficult to say how much of an impact this medication will have, but I look forward to having more potential treatment options for male pattern hair loss,” says Dr. Knox.

Below, you’ll find answers to some common questions about Breezula.

Is Breezula available in the U.S.?

While the acne-fighting version of clascoterone called Winlevi is FDA approved in the United States, Breezula for hair loss has yet to receive FDA approval, which means it’s not yet available here. 

Right now, Breezula is undergoing phase III trials. If and when this stage is completed, the drug can move on to the FDA approval stage, after which it would become available in the U.S.

When will Breezula be available?

It’s hard to say. Trials for Breezula are expected to be completed sometime in 2025, but potential US/EU approval may not occur until several years after that, possibly around 2028.

Should it win approval, Breezula will be the only topical androgen receptor inhibitor for androgenetic alopecia (AGA), and it will also become the first drug with a new mechanism of action for AGA in more than 20 years.

Is Breezula for men and women?

Yes, Breezula can be used by both men and women. Right now, it’s approved for the treatment of acne vulgaris in adolescents and adults. If it’s approved by the FDA for hair loss, it would be the first topical anti-androgen for hair loss in both men and women.

Breezula may be the hair health hero and baldness beater that everyone wants, but in all likelihood, it will just be another tool in the toolbox for fighting hair loss.  

Before we can tell you how effective it will be with any certainty, the FDA needs to look into it — and that’s still an ongoing process. 

Here’s what to remember:

• Breezula is a new, name-brand version of the generic clascoterone. It is a topical solution in development that may be used to treat androgenetic alopecia. 

• While the clinical trials for Breezula seem promising so far, it’s likely a year or more away from the American market. It will have to go through a rigorous FDA approval process after phase III trials are complete before it enters the market.

• Whether this not-yet-available drug can stop hair loss and promote new hair growth safely remains to be seen. But early trials seem promising.

• Luckily, there are viable alternatives to treat hair loss while waiting for Breezula to hit the market. There are already two FDA-approved hair growth products on the market: finasteride and minoxidil.

Until potential FDA approval of Breezula, our blog has great tips for hair growth for guys who want to harness some science to fight male pattern baldness and other types of hair loss.

You can also consider already FDA-approved options like finasteride (the active ingredient in Propecia ^® ) and minoxidil (the active ingredient in Rogaine ^®). We offer both, with options including minoxidil foam, minoxidil solution, and a combo topical finasteride & minoxidil spray.