A 21-Day, Randomized, Controlled Study to Evaluate the Skin Irritation Potential of BAY H006689, Naproxen 10% Topical Gel in Healthy Subjects Using a Cumulative Irritant Patch Test Design

Researchers are looking for a better way to treat muscle and joint pains. Researchers have seen that medicines which help reduce pain and inflammation could be safer when applied directly to the skin, called topical application, than when taken by mouth. However, recent studies have found that using these medications on the skin can sometimes cause skin reactions such as redness, itching, or irritation in the area where the medication is applied.

BAYH006689 topical gel is under development for the treatment of muscle and joint pains.

In this study, participants will be healthy and will not benefit from BAYH006689. However, the study will provide information about how to test BAYH006689 in future studies with people who have muscle and joint pain.

The main purpose of this study is to check whether BAYH006689 topical gel causes any irritation to the skin in healthy participants using a patch test called cumulative irritant patch test design. To do this, researchers will apply gel to participants' skin once a day for 21 days. Skin reactions will be assessed using a scale which will provide a score for redness, swelling, and other signs of skin irritation.

In this study, researchers will randomly assign 4 sites adjacent to each other, on the back of the participants' bodies just below the shoulder blades.

The following treatment gels will be applied using a patch.

• BAYH006689
• Placebo, which looks like the study drug, but does not have any medicine in it.
• 0.2% sodium lauryl sulfate (is a common ingredient in personal care products and when in contact with skin it could cause some skin irritation)
• 0.9% saline

Each participant will be in this study for 22 days, which includes:

• a visit to the clinic within 21 days of the study start, to confirm if the participant can take part in the study.
• participants will receive their assigned treatment gels at the identified skin site for 21 days.
• an end of study visit on Day 22, during which the researchers will remove the designed patches and assess any signs of skin irritation.

During the study, the doctors and their study team will:

• do physical examinations
• check participants' health by performing urine tests
• ask the participants questions about how they are feeling and what adverse events they are having An adverse event is any medical problem that a participant has during a study. Doctors keep track of all adverse events, irrespective if they think it is related or not to the study treatment.