The Food and Drug Administration (FDA) has approved Klisyri® (tirbanibulin; Almirall) ointment for the topical treatment of actinic keratosis (AK) of the face or scalp.

Klisyri is a novel, first-in-class microtubule inhibitor. The approval was based on data from 2 multicenter, randomized, double-blind, phase 3 trials (AK003 [N=351] and AK004 [N=351]) that evaluated the efficacy and safety of Klisyri ointment in adults with AK on the face or scalp. Patients were randomized 1:1 to receive Klisyri or placebo once daily for 5 consecutive days. The primary end point for both studies was the proportion of patients achieving complete clearance (100%) of AK lesions at day 57. A key secondary end point was partial response at day 57, defined as greater than or equal to 75% clearance of AK lesions. 

Results from both studies showed that Klisyri-treated patients met the primary end point, achieving statistically significant clearance of AK lesions at day 57. In AK003, 44% of patients treated with Klisyri achieved complete clearance compared with 5% in the placebo group (P <.0001). In AK004, complete clearance was observed in 54% of patients treated with Klisyri compared with 13% in the placebo group (P <.0001). Moreover, a significantly greater proportion of patients treated with Klisyri had partial AK clearance vs those in the placebo arms in both AK003 (68% vs 16%; <.0001) and AK004 (76% vs 20%; <.0001).

Klisyri-treated patients who achieved complete clearance of AK lesions at day 57 were followed for up to 12 months to determine the recurrence rate, defined as the proportion of patients with any identified AK lesion (new or previous lesion). Among 174 patients, the recurrence rate at 12 months post-day 57 was 73%.

As for safety, the most common adverse reactions (incidence of greater than or equal to 2%) reported with Klisyri included local skin reactions, application site pruritus, and application site pain. “Of note, no patients withdrew from the study due to adverse events,” added Ayman Grada, MD, head of R&D and Medical Affairs for Almirall US.

Klisyri will be supplied in boxes of 5 single-use packets, each packet containing 250mg of tirbanibulin ointment 1%. The product is expected to be available in the first quarter of 2021.

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1.    Athenex announces FDA approval of Klisyri® (Tirbanibulin) for the treatment of actinic keratosis on the face or scalp. [press release]. Buffalo, NY: Athenex, Inc.; December 15, 2020. 

2.    Almirall announces FDA approval of Klisyri® (tirbanibulin), a new innovative topical treatment for actinic keratosis. [press release]. Exton, PA: Almirall; December 15, 2020.

3.    Klisyri [package insert]. Exton, PA: Almirall; 2020.