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KOH 5% solution versus diclofenac 3% for the treatment of actinic keratosis - Results from a three-armed RCT
U Reinhold1, N Leitz2, R Dominicus3
1MVZ Dermatologisches Zentrum Bonn GmbH, Bonn, Germany.
Background:
Actinic Keratosis (AK) has the potential to progress into malignant cancer, thus necessitating timely and effective treatment. Despite several existing therapies, there is still a need for effective, well-tolerated therapeutic options, especially in the early treatment of patients with few isolated lesions in primary care.
Objectives:
To investigate the efficacy and safety of potassium hydroxide (KOH) 5% solution in comparison to diclofenac 3% gel and placebo for the treatment of mild-to-moderate AK.
Methods:
In this randomized controlled trial, patients with mild or moderate AK applied KOH or placebo solution double-blinded twice daily for 28 days, followed by a 28-day off-treatment phase (1 treatment cycle) for up to three treatment cycles or until treatment success. In a third arm, diclofenac was applied twice daily for 60 days and evaluated investigator-blinded. The primary endpoint was treatment success, defined as complete clearance (CC) of all initially present AK lesions per patient at the end of treatment (EOT).
Results:
In total, 631 patients were enrolled. Treatment success was achieved by 45.2% of patients treated with KOH, compared to 23.8% and 22.9% with diclofenac and placebo, respectively. Similarly, complete remission rates for individual lesions were higher with KOH (65.0%) than with diclofenac (45.9%) or placebo (39.9%). KOH showed a faster onset of action, with higher CC rates already after 1 month compared to diclofenac (16.0% vs. 9.2%) and converging efficacies after 6 months. Most adverse reactions were mild and localized, with comparable tolerability of KOH and diclofenac.
Conclusions:
KOH 5% solution proved superior to placebo and, when compared to diclofenac 3% gel, demonstrated significantly higher efficacy at EOT, as well as faster onset of action with comparable long-term efficacy and tolerability. KOH 5% solution is a valuable addition to the available treatment options for lesion-directed therapy in patients with mild-to-moderate AK.
Gov Identifier:
NCT04552327.
Insights
Potassium hydroxide (KOH) 5% solution demonstrated superior efficacy for treating actinic keratosis (AK) compared to diclofenac and placebo. This treatment offers a faster onset and comparable tolerability, making it a valuable option for AK management.
Area of Science:
- Dermatology
- Oncology
- Pharmacology
Background:
- Actinic Keratosis (AK) poses a risk of progressing to malignant skin cancer.
- There is an ongoing need for effective and well-tolerated treatments for AK, particularly in primary care settings for patients with limited lesions.
Purpose of the Study:
- To evaluate the efficacy and safety of potassium hydroxide (KOH) 5% solution.
- To compare KOH 5% solution against diclofenac 3% gel and placebo for treating mild-to-moderate AK.
Main Methods:
- A randomized controlled trial involving 631 patients with mild-to-moderate AK.
- Patients received KOH 5% solution or placebo twice daily for 28 days, followed by a 28-day off-treatment phase, for up to three cycles.
- A separate group received diclofenac 3% gel twice daily for 60 days.
Main Results:
- Treatment success (complete clearance of AK lesions) was achieved in 45.2% of patients treated with KOH, versus 23.8% for diclofenac and 22.9% for placebo.
- KOH demonstrated a higher complete remission rate for individual lesions (65.0%) compared to diclofenac (45.9%) and placebo (39.9%).
- KOH exhibited a faster onset of action and comparable tolerability to diclofenac, with most adverse reactions being mild and localized.
Conclusions:
- Potassium hydroxide 5% solution is significantly more effective than placebo and diclofenac 3% gel for treating mild-to-moderate AK at the end of treatment.
- KOH 5% solution offers a faster onset of action with comparable long-term efficacy and tolerability.
- KOH 5% solution represents a valuable new therapeutic option for lesion-directed treatment of actinic keratosis.
