FDA expands approval for Almirall's Klisyri to treat actinic keratosis

Almirall has announced that the US Food and Drug Administration (FDA) has expanded its approval of Klisyri (tirbanibulin) to treat actinic keratosis (AK), a common precancerous skin condition. This expanded approval allows the use of the microtubule inhibitor ointment on areas of the face or scalp up to 100 cm².

Actinic keratosis is characterized by rough, scaly patches on the skin and is a significant precursor to squamous cell carcinoma, accounting for approximately 60% of cases of this second most common form of skin cancer. A recent survey conducted by Almirall in conjunction with AK Global Day 2024 indicates that AK has a prevalence of 13.3% in Europe, and 50% of the population experiences sunburn at least once annually.

Klisyri was first approved by the FDA in December 2020. The recent broadened approval was underpinned by a supplemental new drug application (sNDA), which included data from an additional phase 3 clinical safety study. This study involved over 100 adult patients in the US and met all primary endpoints, reaffirming the drug’s safety and tolerability.

The phase 3 trial specifically assessed the use of Klisyri on a 100 cm² area of the face or balding scalp. Results were consistent with previous pivotal trials, which had focused on a smaller area of 25 cm². Both local skin reactions and treatment-related adverse events aligned with earlier findings, and the reduction in AK lesion count was comparable to initial studies.

Karl Ziegelbauer, Chief Scientific Officer at Almirall, highlighted the significance of this approval, noting that it represents a major advancement for both patients and dermatologists. "The FDA’s approval of the use of Klisyri for AK on an extended surface of the face or scalp is a significant step forward for both patients and treating dermatologists. With patients experiencing AK over larger surface areas, dermatologists are looking for ways to treat the entire affected area to help prevent further lesion progression," Ziegelbauer stated.

Klisyri has already secured multiple approvals, including from the EU and the UK in 2021. In these regions, it is approved for a once-daily application over five days to treat AK of the face and scalp in adults.

Additionally, in March 2024, Almirall entered into an exclusive licensing agreement with Eloxx Pharmaceuticals. This deal, valued at over $470 million, involves the oral therapy ZKN-013, which is being developed for rare dermatological diseases.

The expanded FDA approval of Klisyri and Almirall’s strategic partnerships underscore the company’s commitment to addressing unmet needs in dermatology. The ability to treat larger areas affected by AK potentially improves patient outcomes and offers a more viable solution for dermatologists managing this prevalent condition.