What is tirbanibulin ointment?
Tirbanibulin is a synthetic inhibitor of tubulin polymerisation and protein kinase signalling.
It has been formulated into an ointment for the treatment of actinic keratoses (AK), and received a product licence in the USA, UK, and Germany in 2021 (Klisyri®).
What is tirbanibulin ointment used for?
Tirbanibulin ointment is used for the topical treatment of actinic keratoses. Areas of up to 25cm2 of affected sun-damaged skin have been studied on the face, scalp, and forearms, so it is suitable as a field therapy. The short duration of treatment (once daily for 5 days) is a potential advantage over some other self-delivered topical therapies for actinic keratoses.
Atypical, rapidly changing, and hypertrophic actinic keratoses should not be treated with this modality.
How does tirbanibulin ointment work?
- Inhibits tubulin polymerisation and Src kinase signalling.
- Induces p53 expression.
- Causes arrest of cell division and mitosis in proliferating cells.
- Demonstrated in vitro inhibition of keratinocyte proliferation.
What are the benefits of tirbanibulin ointment?
In the two trials (Blauvelt et al.) with a total of 702 patients, tirbanibulin ointment was compared to vehicle, and an assessment of lesion clearance was made at day 57.
- 49% of patients in the tirbanibulin-treated group experienced complete clearance of all actinic keratoses (AKs), compared to 9% of those treated with the vehicle.
- Partial clearance occurred in 72% of the tirbanibulin group, compared to 18% in the vehicle group.
- Of 174 patients who had complete clearance, 124 had one or more recurrent lesions at 1 year of follow-up.
- Only 1 patient who only had a partial response developed a squamous cell carcinoma in the active treatment area; 10 patients developed squamous cell carcinomas outside the vehicle or placebo-treated sites.
These results are favourable when compared to other long-established AK therapies, most of which require longer treatment courses.
What are the disadvantages of tirbanibulin ointment?
Like all topical treatments for actinic keratoses, local inflammatory reactions are common, but as the treatment time is short, they resolve rapidly, encouraging concordance and acceptability.
What are the side effects and risks of tirbanibulin ointment?
Application site pruritus and pain occurred in both the vehicle and active treatment group, but were more severe in those treated with tirbanibulin. The symptoms peaked at day 8, and were settling by day 15.
Serious adverse events were uncommon and considered to be unlikely to be due to vehicle or active treatment.
What are the contraindications with tirbanibulin ointment?
- Pregnancy and breastfeeding.
- Intolerance or allergy to any of the excipients (including propylene glycol).
- Atypical, rapidly changing, and hypertrophic actinic keratoses should not be treated with this modality.
Due to the mode of delivery and poor percutaneous absorption, it is unlikely to interact with systemic medications.
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).