Breezula treatment (clascoterone 5%): the complete evidence-based guide for 2026

Breezula Treatment (Clascoterone 5%): The Complete Evidence-Based Guide for 2026

Androgenetic alopecia (AGA), which is the medical term for male and female pattern hair loss, affects between 1.2 and 2 billion men worldwide, yet our medical therapeutic toolbox has barely evolved in over three decades. Reliable options like minoxidil and finasteride, which were both approved in the 1980s and 1990s, remain the central pillars of treatment today. Breezula, the developmental trade name being advanced by Cosmo Pharmaceuticals for its clascoterone 5% topical solution, represents the first genuinely novel pharmacological pathway to reach late-stage clinical trials in more than thirty years.

What is Breezula and why is it different?

Breezula is the developmental brand name for a 5% topical solution of clascoterone, an active substance also identified by its chemical name cortexolone 17α-propionate (a synthetic compound structured to target hormone receptors locally). This exact same active molecule, formulated at a lower 1% concentration, is already fully approved by European and American regulators (the EMA and FDA) under the brand name Winlevi to treat moderate acne vulgaris in patients who are 12 years of age and older.

From a chemical standpoint, clascoterone belongs to the same basic steroid structural family as dihydrotestosterone (DHT) and spironolactone. Its characteristic four-ring carbon backbone is nearly identical to DHT, which is precisely the structural trick that allows it to slip directly into cellular androgen receptors (the biological locks on hair cells) and effectively block them from receiving harmful hormonal signals.

What makes Breezula truly unique is not simply that it opposes DHT, but rather the precise way and location in which it operates: it acts locally on the scalp, blocks the androgen receptor directly at the site of the hair follicle to shield it, and is rapidly deactivated by metabolic enzymes the moment it escapes into the general bloodstream, preventing systemic hormonal disruptions.

How does clascoterone work?

The hormonal roots of pattern hair loss

In pattern hair loss, circulating testosterone is converted by an enzyme called 5-alpha reductase (a biological catalyst) into a much more potent hormone called DHT, which then binds to androgen receptors housed within the dermal papilla (the tiny, nutrient-rich command center) at the base of each hair follicle. When activated, these receptors shrink the follicle, shorten the active growth phase (known as the anagen phase), and produce thinner hairs, a destructive process known as miniaturisation.

Block the receptor, not the enzyme

• Finasteride and dutasteride act systemically to inhibit the 5-alpha reductase enzyme, reducing DHT levels everywhere in the body.

• Spironolactone blocks hormone receptors systemically (throughout the whole body) but also affects aldosterone, a hormone responsible for managing salt and water balance.

• Clascoterone operates as a selective, topical androgen receptor antagonist (a targeted local blocker), competing head-to-head with DHT to occupy the receptor docking sites deep inside the hair-producing dermal papilla cells.

In laboratory studies performed on human scalp dermal papilla cells, clascoterone successfully blocked androgen receptor (AR) driven gene transcription (the cellular signals that cause balding) with an effectiveness comparable to finasteride, and it actually outperformed enzalutamide (a potent prostate cancer drug) at reducing DHT-stimulated production of interleukin-6 (IL-6), an inflammatory chemical messenger known to halt hair growth.

Why local action matters

Because Breezula is applied directly to the skin and is rapidly broken down by natural enzymes into an inactive metabolite once absorbed, body-wide exposure remains exceptionally low, with less than 1% of the applied dose appearing in urine tests. This unique metabolic safety valve explains why clascoterone does not reduce circulating levels of DHT in the body and should not trigger the classic systemic side effects (such as fatigue or sexual dysfunction) that concern many oral finasteride users.

Comparing Breezula with existing treatments

Breezula represents a prominent member of a new, emerging category of topical androgen receptor blockers and stands as the most clinically advanced candidate in the pipeline. Other competitive molecules such as pyrilutamide (KX-826) and GT20029 follow a very similar scientific rationale but currently trail behind in the clinical trials process.

What did SCALP-1 and SCALP-2 show?

Study design

SCALP-1 and SCALP-2 are two identically designed, multicentre, randomised, double-blind (where neither doctor nor patient knows who gets the active drug), vehicle-controlled Phase III trials enrolling 1,465 men with mild-to-moderate AGA at 51 clinical sites across the US and Europe. Each study included a 6-month double-blind phase followed by a 6-month extension. The primary endpoint (the main success metric) was the change in Target-Area Hair Count (TAHC), which measures active hair density in a specific scalp area.

What the "539%" number really means

The initial topline data stated that SCALP-1 showed a 5.39-fold relative improvement in TAHC versus the inactive vehicle, while SCALP-2 showed a 1.68-fold improvement, and both results were statistically significant. These figures are relative improvements (compared directly to the changes in the placebo group) rather than absolute increases in total hair count on your head. When the placebo group's change is virtually zero, even a modest absolute gain in the active arm produces a mathematically massive relative percentage.

Why the two studies differ

The gap between these results likely reflects differences in baseline hair loss severity, patient demographics, and site-level differences in how the high-resolution TAHC photography was performed. Crucially, both studies successfully met their primary endpoint, which is the key milestone required for regulatory approvals.

The 12-month extension

In April 2026, Cosmo Pharmaceuticals released the 12-month extension data. Patients who remained on clascoterone continued to gain hair, achieving a 2.39-fold TAHC improvement versus those who were switched over to the inactive vehicle. Conversely, patients who were switched to the vehicle lost part of their gains, confirming that clascoterone works only for as long as it is continuously applied.

Safety profile

Across both SCALP trials, treatment-emergent adverse events were similar between clascoterone and vehicle (the inactive control lotion). Safety data from Winlevi 1% confirm: systemic absorption is well below 1%, mild local reactions on the skin are similar to the vehicle, there is only a reversible HPA axis (hypothalamic-pituitary-adrenal stress axis) dampening under extreme, unrealistic usage conditions, and there are absolutely no systemic anti-androgen effects such as gynecomastia (male breast tissue growth) or reduced libido. Importantly, clascoterone is not a corticosteroid, which are the steroids that can cause skin thinning, despite possessing a chemical steroid backbone.

Important unknowns still include long-term efficacy beyond 12 months, direct head-to-head comparative data versus finasteride or minoxidil, and comprehensive efficacy data in female patients.

European regulatory status

As of mid-2026, clascoterone 5% is not approved anywhere for hair loss, as only the lower-strength Winlevi 1% is authorized for acne. Cosmo is preparing an NDA to the FDA (a New Drug Application in the US) in early 2027 and an MAA to the EMA (a Marketing Authorization Application in Europe) in parallel. Under the EMA centralized review procedure, realistic timelines indicate that the earliest potential EU approval would be late 2027, though 2028 is more likely. Reimbursement by health services is highly unlikely as hair loss is typically classified as a cosmetic issue, meaning Breezula will most probably be a prescription-only, out-of-pocket cost.

Until then, no legitimate pharmacy in the EU can dispense clascoterone 5% for hair loss. Products sold online as "clascoterone lotions" through unregulated, grey-market channels are completely unregulated and highly risky for consumers.

Who might be a good candidate?

• Men aged 18 and older with mild-to-moderate AGA (classified as stages II to V on the Norwood clinical hair loss scale).

• Patients who cannot tolerate or refuse oral finasteride/dutasteride due to side effect concerns.

• Patients who are highly concerned about post-finasteride syndrome (the reports of persistent sexual or cognitive side effects after stopping oral hair loss medication).

• Patients currently using minoxidil who wish to introduce a protective, localized hormone-blocking layer in combination with their current therapy.

• Potentially, surgical patients before or after a hair transplant, used off-label under close dermatological supervision to preserve existing hair.

What about women?

While a Phase II study evaluated clascoterone in female patients, the final results are not yet available, and the SCALP trials enrolled only men. If approved based on current clinical data, the initial indication will be restricted to male AGA. Because female AGA involves highly complex hormonal contexts (including PCOS or polycystic ovary syndrome, menopause, and thyroid issues), dedicated clinical trials for women will be required.

Combination therapy

• Minoxidil to stimulate hair growth by widening blood vessels and boosting local circulation (the vascular pathway).

• Clascoterone 5% to block the local androgen receptors directly on the hair follicles.

• Adjuvants (complementary treatments) such as microneedling to enhance product absorption, low-level laser therapy (LLLT), or platelet-rich plasma (PRP) therapy.

• Oral 5-AR inhibitors (like finasteride) reserved exclusively for patients who are fully comfortable with systemic, body-wide DHT reduction.

Conclusion

Breezula represents the most credible and scientifically sound therapeutic innovation in pattern hair loss treatment in more than three decades. Its localized mechanism of action addresses a critical, unmet clinical need for patients who wish to avoid systemic anti-androgens. The Phase III trial data are encouraging and the 12-month follow-up study confirms continued hair density gains with a safety profile comparable to the inactive vehicle. That said, the headline relative figures deserve careful, realistic interpretation, and the drug will not be commercially available in Europe before 2027 at the earliest, and more realistically in 2028.

At Hairdex, we monitor these medical developments closely with rigorous attention. Any decision to include Breezula in a personal hair loss strategy should always be made in consultation with a qualified dermatologist or a trichologist (a certified hair and scalp specialist).

Frequently Asked Questions

What is Breezula and how does it work?

Breezula is a clascoterone 5% topical solution, a local anti-androgen therapy designed to be applied twice daily directly to the scalp. It binds to cellular androgen receptors within the hair follicles to block DHT, without lowering circulating DHT levels in the rest of your body.

Does clascoterone cause sexual side effects like finasteride?

Available clinical data show no signal of sexual dysfunction, reduced libido, gynecomastia (male breast development), or feminising effects, because systemic absorption is negligible and the active molecule is rapidly inactivated once it enters the bloodstream.

When will Breezula be available in Europe?

The earliest expected approval in the EU is projected for late 2027, though 2028 is a more realistic timeline for availability. It will most likely be a prescription-only treatment that must be paid for out-of-pocket.

Can Breezula be combined with minoxidil?

From a biological standpoint, yes, as they act via entirely different pathways (minoxidil stimulates local blood flow, while clascoterone blocks hormones), but formal clinical combination trials are still lacking.

Is Breezula suitable for women?

Not yet. The Phase III registration trials enrolled only male patients, so dedicated, female-specific clinical studies will be required before regulators can approve any official indication for women.

References

[1] Cosmo Pharmaceuticals. Cosmo announces breakthrough Phase III Topline results from Scalp 1 and Scalp 2 for Clascoterone 5% Solution in male hair loss, showing up to 539% relative improvement in Target-Area Hair Count vs placebo; US and EU submissions are underway. Cosmo Pharmaceuticals News. 2025. Read the source

[2] Hebebrand M. Clascoterone 5% Delivers Strong Phase 3 Hair-Growth Results. Dermatology Times. 2025. Read the source

[3] Cosmo Pharmaceuticals. Phase III 12-Month Data for Clascoterone 5% Topical Solution Confirm Positive Safety for Chronic Use and Continued Hair Growth, both of which are Statistically Significant. Nasdaq Press Release. 2026. Read the source

[4] A Study to Evaluate the Efficacy and Safety of Clascoterone Solution in Treatment of Male Pattern Hair Loss (SCALP2). ClinicalTrials.gov (NCT05914805). Read the source

[5] A Study to Evaluate the Efficacy and Safety of Clascoterone Solution in Treatment of Male Pattern Hair Loss (SCALP1). ClinicalTrials.gov (NCT05910450). Read the source

[6] Rosette C, Rosette N, Mazzetti A, Moro L, Gerloni M. Cortexolone 17α-Propionate (Clascoterone) is an Androgen Receptor Antagonist in Dermal Papilla Cells In Vitro. J Drugs Dermatol. 2019. Read the source

[7] Rosette C, Agan FJ, Mazzetti A, Moro L, Gerloni M. Cortexolone 17α-propionate (Clascoterone) Is a Novel Androgen Receptor Antagonist that Inhibits Production of Lipids and Inflammatory Cytokines from Sebocytes In Vitro. J Drugs Dermatol. 2019. Read the source

[8] Sanchez C, Keri J. Androgen Receptor Inhibitors in the Treatment of Acne Vulgaris: Efficacy and Safety Profiles of Clascoterone 1% Cream. Clin Cosmet Investig Dermatol. 2022. Read the source

[9] Devjani S, Ezemma O, Kelley KJ, Stratton E, Senna M. Androgenetic Alopecia: Therapy Update. Drugs. 2023. Read the source

[10] Committee for Medicinal Products for Human Use (CHMP). Winlevi (Clascoterone) Assessment Report. European Medicines Agency. 2026. Read the source

[11] Di Stefano AFD, Radicioni MM, Garhöfer G, et al. Pharmacokinetics, Safety, and Skin Irritation and Sensitization Potential of Clascoterone Cream in Early-Phase Clinical Study Participants. Clin Pharmacol Drug Dev. 2025. Read the source

[12] Marks DH, Prasad S, De Souza B, Burns LJ, Senna M. Topical Antiandrogen Therapies for Androgenetic Alopecia and Acne Vulgaris. American Journal of Clinical Dermatology. 2020. Read the source