What is clascoterone?
Topical clascoterone cream 1% (Winlevi®) is a novel androgen receptor inhibitor used for the treatment of acne vulgaris in patients aged 12 years and older.
Clascoterone was approved by the US Food and Drug Administration (FDA) in August 2020 for the treatment of acne vulgaris, but is not yet available in some countries including Australia and New Zealand at the time of writing.
What is clascoterone used for?
There have been several trials to date demonstrating the efficacy and safety of clascoterone cream 1% for moderate-to-severe acne vulgaris.
- A pilot study (Trifu et al. 2011) found that clascoterone cream 1% was significantly better than placebo in reducing inflammatory lesion count, total lesion count, and acne severity index in men with facial acne.
- They also found clascoterone to be more effective (but not reaching statistical significance) in reducing total lesion count and acne severity index when compared to tretinoin 0.05% cream.
- Two landmark phase III trials (CB-03-01/25 and CB-03-01/26) with 1440 patients found that significantly more patients (aged 9 years and older) treated with clascoterone cream 1% achieved treatment success (as defined by ≥2/4 reduction in Investigator Global Assessment severity scores) compared to vehicle cream after 12 weeks (18.4–20.3% clascoterone group vs 6.5–9.0% vehicle group, p <0.001).
- Clascoterone was also associated with a statistically significant greater absolute reduction in lesion counts (inflammatory, non-inflammatory, and total) from baseline to 12 weeks compared to vehicle cream.
Clascoterone has also been suggested to be an effective treatment for androgenetic alopecia from preliminary studies, although it is not currently approved for use in this context.
The proposed mechanism of action is through antagonizing dihydrotesterone’s effects on dermal papilla cells, reducing the production of prostaglandin D2 and interleukin 6 (IL-6), regulating secretion of sebum, and reducing hair miniaturisation.
How does clascoterone work?
Clascoterone or cortexolone 17α-propionate is the first of its kind — a topical treatment targeting the hormonal pathogenesis of acne vulgaris.
It is postulated that clascoterone competes with androgens such as dihydrotestosterone (DHT) for androgen receptors, inhibiting the downstream signalling pathways of androgen receptor-regulated gene transcription in sebaceous glands and dermal papilla cells responsible for acne pathogenesis.
Dosage and administration
Clascoterone is currently available as a 1% (10mg/g) cream. A thin, uniform layer to the affected area twice a day: morning and evening is recommended.
What are the benefits of clascoterone?
Targeting androgen inhibition is a known effective treatment for acne vulgaris, as is seen in current utilisation of the anti-androgenic effects of spironolactone and some oral contraceptives. These, however, can cause systemic adverse effects and are also contraindicated in males.
Clascoterone 1% cream has selective topical activity, limiting systemic androgenic effects. Clascoterone is also highly potent, and found to be four times more potent than progesterone.
What are the disadvantages of clascoterone?
Side-effects and risks
The reported adverse effects of clascoterone cream 1% are mild and infrequent. Clascoterone has a similar safety profile to vehicle cream from existing studies.
Local skin reactions may include:
- Skin atrophy
- Striae rubrae
Reported treatment-emergent adverse events (<2%) included:
- Oropharyngeal pain.
- Paediatric patients may be more susceptible to systemic adverse effects.
- A pharmacokinetic study in 42 patients found hypothalamic-pituitary-adrenal (HPA) axis suppression at day 14 of treatment with 4g-6g BD of clascoterone. However, all patients returned to normal HPA axis 4 weeks after the end of the treatment.
- Hyperkalaemia was observed in some patients during the clinical trials (5% treated with clascoterone compared to 4% of vehicle-treated subjects).
What are the contraindications with clascoterone?
There are currently no known contraindications from the existing studies.
There is, however, a lack of safety evidence available for the use of clascoterone in patients less than 12 years of age, in pregnancy, during lactation (breastfeeding), and in those over 65 years of age.
We suggest you refer to your national drug approval agency such as the Australian Therapeutic Goods Administration (TGA), US Food and Drug Administration (FDA), UK Medicines and Healthcare products regulatory agency (MHRA) / emc, and NZ Medsafe, or a national or state-approved formulary eg, the New Zealand Formulary (NZF) and New Zealand Formulary for Children (NZFC) and the British National Formulary (BNF) and British National Formulary for Children (BNFC).