Randomized, Double-Blind Study on the Efficacy and Safety of 5% Potassium Hydroxide Solution Versus Placebo in Treating Mild to Moderate Actinic Keratosis

The primary objective of this study is to demonstrate the **superiority** of the clinical efficacy of Solcera, a 5% **potassium hydroxide** solution, in the treatment of mild to moderate **actinic keratosis** compared to a placebo. Actinic keratosis is a precancerous condition characterized by rough, scaly patches on the skin, primarily due to prolonged sun exposure. Establishing the efficacy of Solcera is clinically relevant as it may offer a more effective treatment option for patients, potentially reducing the risk of progression to squamous cell carcinoma.

Secondary objectives include evaluating the safety profile of Solcera, ensuring that the treatment is not only effective but also safe for patient use. This assessment is crucial for determining the overall benefit-risk ratio of the treatment in clinical practice.

The clinical trial focuses on evaluating the efficacy of solcera, a 5% potassium hydroxide solution, for the treatment of **actinic keratosis**. The study population includes both male and female participants, aged 18 to 89 years, with mild to moderate actinic keratosis lesions. Participants are required to have at least one palpable or clinically/dermatoscopically apparent lesion, classified as severity grade I or II according to Olsen. The trial includes individuals who can either self-administer the treatment or have an assistant trained by the investigator to assist with the application. The sponsor has not provided information regarding the total number of participants. The study population is selected based on the ability to provide written informed consent and the presence of treatable lesions. The trial does not specify any particular lifestyle considerations such as diet or physical activity. Both vulnerable and non-vulnerable populations are included in the study.

The clinical trial is a **randomized**, double-blind, controlled study designed to evaluate the efficacy and safety of a 5% **potassium hydroxide** solution, Solcera, compared to a placebo in the treatment of mild to moderate **actinic keratosis**. The trial is structured in a multistage, two-arm format and is expected to conclude by January 31, 2030, with recruitment starting on March 1, 2025. Participants will be randomly assigned to receive either the investigational product or a placebo, with the primary objective being to demonstrate the superiority of Solcera in achieving complete clearance of actinic keratosis lesions.

The study will involve several visits, beginning with an inclusion (screening) visit to assess eligibility based on criteria such as age (18 to 89 years) and the presence of at least one palpable or clinically apparent actinic keratosis lesion. Participants will provide written informed consent before enrollment. The trial will proceed through multiple treatment cycles, with follow-up visits scheduled to monitor treatment success and safety. The primary endpoint is the complete clearance of lesions, confirmed dermatoscopically, at the end of treatment (EOT) visit, which occurs after the off-phase of the treatment cycle. Secondary endpoints include lesion-related treatment success, response to therapy, and assessment of adverse events.

Participants are expected to be involved in the study for a maximum treatment period of 12 weeks, with the possibility of early termination if significant adverse events occur or if the participant withdraws consent. Compliance and dropout rates will be evaluated throughout the trial. The study aims to provide comprehensive data on the efficacy, tolerability, and safety of the investigational product, with results evaluated separately for each phase of the trial.

The clinical trial involves the evaluation of two treatments for mild to moderate **actinic keratosis**. The experimental medication, **Solcera**, is a 5% **potassium hydroxide** solution formulated as a cutaneous solution. It is manufactured by Infectopharm Arzneimittel und Consilium GmbH. The solution is applied topically, with a maximum daily dose of 100 mg and a total maximum dose of 4200 mg over a treatment period of up to 12 weeks. The primary objective is to assess the clinical efficacy of Solcera compared to a placebo.

The placebo used in this study is **Preserved water**, which serves as a comparator treatment. It is administered in the same pharmaceutical form and route as Solcera, ensuring blinding and consistency in the trial design. The placebo is applied topically, mirroring the administration schedule of the experimental treatment. This design allows for a direct comparison of the efficacy and safety of Solcera against a non-active treatment, providing a robust assessment of its therapeutic potential.

The efficacy of the investigational product, Solcera (5% **potassium hydroxide** solution), will be assessed in a clinical trial aimed at treating mild to moderate actinic keratosis. The primary endpoint for evaluating efficacy is the treatment success, defined as "complete clearance," which is the complete, dermatoscopically confirmed remission of all actinic keratosis lesions present at the start of treatment. This will be assessed at the control visit after the end of treatment, which may occur after the first, second, or third treatment cycle, depending on the course of remission. The evaluation will be conducted separately for each phase of the trial.

Secondary endpoints include lesion-related treatment success, which is the "complete remission" of actinic keratosis lesions documented at least once until the end of treatment. This will be evaluated at all visits, excluding the end of treatment, and separately for each phase. Additional secondary endpoints involve assessing treatment success in relation to all actinic keratosis lesions, including those occurring after the start of treatment, and evaluating the percentage reduction in the number of lesions per participant compared to baseline. The trial will also monitor participants for relapses and assess the healing stage of lesions over time. Efficacy, tolerability, and overall assessment by both the investigator and the trial participant will be graded on a scale of 1 to 6 at the end of treatment and during the follow-up visit. These assessments will be conducted separately for each phase of the trial.