CB 03 01 / Breezula (Clascoterone) for Hair Loss: Research, Results and How to Use It - nicehair.org

CB 03 01 / Breezula (Clascoterone) for Hair Loss: Research, Results and How to Use It

CB 03 01 is a topical hair loss treatment that works by binding with androgen receptors in the hair follicles, helping to reduce the amount of DHT that’s able to bind with the receptors.

By inhibiting the androgen receptors, CB 03 01 reduces the impact DHT has on the hair follicles

CB 03 01 is the code name for the hair loss treatment, also known as Clascoterone, that’s currently being developed and tested by Cassiopea. However, the chemical is available to purchase online as a research chemical, for use at the user’s own risk. The potential treatment is also referred to as ‘Breezula’.

CB 03 01 is a steroidal antiandrogen that has an antagonist effect on the androgen receptor. This is absolutely key to the effect of the topical. By inhibiting the androgen receptors, CB 03 01 reduces the impact DHT has on the hair follicles.

Clascoterone has been determined to increase hair growth by competing with androgens for the same receptor. Clinical Phase II results of Clascoterone are shared by Rosette et al. These results are particularly interesting because an effective topical anti-androgen may be able to protect the hair follicles from androgen hormones without causing the sexual side effects of oral anti-androgens.


Clascoterone has an end of Phase II meeting with FDA scheduled for November 2019. The results of Phase II are promising for hair loss treatment. It seems that the topical formulation of 7.5% showed the most hair count at the end of the 6 months.

How it works

Androgenetic alopecia is, at least to some extent, caused by the hormone dihydrotestosterone (DHT) binding with androgen receptors in the scalp hair follicles.

Clascoterone, a new chemical entity, is a proposed first in class topical androgen receptor inhibitor under FDA review for the treatment of acne and in late-stage development for androgenic alopecia.

Clascoterone competes with androgens, specifically DHT, for binding to the androgen receptors within the sebaceous gland and hair follicles. When applied directly to the skin surface, Clascoterone appears to target local androgen receptors within the skin. Because of Clascoterone’s likely local effect at the site of application, systemic side effects are minimized.

Clascoterone is metabolized to cortexolone, a metabolite with a known safety profile. Due to its rapid metabolism and local activity, there appears to be limited systemic exposure to Clascoterone and thus potential systemic side effects are minimized. In other words, because the chemical is metabolized quickly in the scalp, it’s anti-androgen properties are less likely to affect other parts of the body.

How to use it

2.5, 5, 7.5 % concentrations of Clascoterone were tried twice a day in the human Phase II study. Precise concentration and posology would be determined by the results of advanced trials.

Has CB 03 01 been approved for sale as a hair loss treatment?

CB 03 01 hasn’t been tested on humans for hair loss, but human clinical trials have been conducted for the treatment of acne. You can see the research here.

Buy CB 03 01 Online

CB 03 01 hasn’t been approved for sale as a hair loss treatment. However it can be purchased as a ‘research chemical’. I’ve seen CB 03 01 sold online at Kane Shop and Alibaba.


While clinical Phase II results are promising, it would be logical to wait for larger-scale results to be confident about safety and efficacy. Phase III trials (with greater participation than phase II) are planned for 2020.

Cassiopea stock value up 25%

Cassiopea is the company that’s developing CB 03 01. Over the last three years, the company’s share value has risen 25%. The company has very low revenues and profit, so it’s possible that investors are buying the shares based on research into their future products. One such product is the promising androgen receptor inhibitor CB 03 01 (AKA Breezula AKA Clascoterone). Perhaps the investors know something about a possible product release that we don’t?

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  1. 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. Journal of drugs in dermatology: JDD 18, 197-201 (2019).
  2. McElwee, K. J. & Shapiro, J. S. Promising therapies for treating and/or preventing androgenic alopecia. Skin Therapy Lett 17, 1-4 (2012).
  3. Mazzetti, A., Moro, L., Gerloni, M. & Cartwright, M. A Phase 2b, Randomized, Double-Blind Vehicle Controlled, Dose Escalation Study Evaluating Clascoterone 0.1%, 0.5%, and 1% Topical Cream in Subjects With Facial Acne. Journal of drugs in dermatology: JDD 18, 570-570 (2019).
  4. Fraser, K. A. (Springer, 2019).
  5. Timmins, P. Industry update: the latest developments in the field of therapeutic delivery, July 2018. Therapeutic delivery 9, 797-809 (2018).