The aim of this proof of principle study is to evaluate efficacy and safety of the sequential application of two marketed products for the treatment of acne vulgaris, using the Split-Face model

Inclusion Criteria:

• Subjects having understood and signed an informed consent form
• Male or female subjects who are 18 to 35 years (both included) of age presenting acne vulgaris of the face.
• A minimum of 10 inflammatory lesions (papules and pustules) on the entire face, and a minimum of 20 non-inflammatory lesions (open comedones and closed comedones) on the entire face.
• Disease severity grade as mild or moderate according to the investigator's global assessment (grade 2 or grade 3)

Exclusion Criteria:

• Females who are pregnant, of child-bearing potential and who wish to become pregnant during the study, or who are breast feeding.
• Subjects with any acne cysts or more than one nodule per hemiface.
• Subjects with acne conglobata, acne fulminans, secondary acne (e.g. chloracne, drug-induced acne), or any acne requiring systemic treatment.
• Subjects with a dark pigmentation of the skin or skin type that may, in any way, confound interpretation of the study results (skin type V or VI on Fitzpatrick scale.
• Subjects with other facial skin disorders that may interfere with study assessments.
• Subjects who will use medicated cosmetics and/or soaps (including soaps containing antibacterial agents such as benzoyl peroxide, keratolytic agents such as salicylic acid, skin fresheners/astringents or aftershave products) on the face for the duration of the study.
• Subjects with a history of actinic keratosis on the face or skin cancer.
• Use of hormonal oral contraceptives for acne control for less than 6 months prior to the randomisation.
• Subjects using one of the following systemic medication within 4 weeks before the randomisation and during the study, which could have an effect on the trial disease.
• systemic corticosteroids,
• anti-acne drugs,
• oral retinoids
• any immunosuppressive drugs.
• Subjects using systemic NSAIDs (including aspirin) within 1 week before the randomisation and during the study.
• Subjects using paracetamol within 1 week before the randomisation. Paracetamol will be allowed during the study with a maximum dose of 1g twice daily and for a maximum of 3 consecutive days
• Subjects using one of the following topical medication within 2 weeks before the randomisation and during the study, which could have an effect on the trial disease:
• anti-inflammatory drugs (e.g. topical corticosteroids, NSAIDs),
• anti-acne drugs,
• topical retinoids,
• topical antibacterial agents
• any topical immunosuppressive drugs.
• Subjects with known or suspected hypersensitivity to component(s) of the investigational products or other nonsteroidal anti- inflammatory drug NSAIDs (e.g., aspirin, diclofenac, ibuprofen, ketoprofen).
• Subjects with presence of any clinically significant gastrointestinal pathology (e.g. chronic diarrhea, inflammatory bowel diseases), unresolved gastrointestinal symptoms (e.g. diarrhea, vomiting).
• Subjects with known presence of active peptic ulcer.
• Subjects with history (during the last 10 years) or known presence of asthma.
• Subjects with history (during the last 5 years) or known presence of rhinitis or urticaria

Adverse events were collected from study start untill 43 (±2)days after the last on-treatment visit if an AE (serious or non-serious) classified as possible or probably related to the study treatment was ongoing at the last on-treatment visit.