Photodynamic Therapy (PDT) With Methyl Aminolevulinate (MAL) Cream in Moderate to Severe Acne

For the second part: All patients will receive 4 PDT sessions 2 weeks apart using a light dose of 37 J/cm2. One treatment group will receive vehicle cream, while the other 2 groups will receive MAL cream with a concentration of 40 mg/g and 80 mg/g, respectively. The MAL and vehicle cream will be applied in a thin layer on clean skin and left for 1.5 hours under occlusion before illumination.

Inclusion criteria

• Female and male patients, age 15 to 40 years with moderate to severe facial acne vulgaris (IGA score 3-4).
• Patients with skin type I to IV (Fitzpatrick).
• Patients with 20 to 100 inflammatory lesions (papules, pustules, and nodules) on the face excluding lesions on the nose and in the peri-ocular area.
• Patients with up to 200 noninflammatory lesions (open and closed comedones) on the face.
• Patients with no more than 2 nodular lesions on the face.
• Patients who are surgically sterile, postmenopausal, abstinent, or willing to use an adequate means of contraception including birth control pills, or barrier methods and spermicide for at least 14 days prior to Day 0. Patients using birth control pills must have used the same product and dose for at least 6 months and must agree to stay with the same product and dose for an additional 6 months.
• Patients must be willing and capable of following study instructions to the extent and degree required by the protocol.
• Patients must sign the approved informed consent form prior to any study procedures.
• Patients must be willing to be photographed. Patients must be willing to sign a photography consent form.

Exclusion criteria

• Known allergy to MAL, to a similar PDT compound, or to excipients of the cream.
• Participation in other clinical studies either concurrently or within the last 30 days.
• Patients who have a condition or who are in a situation, which, in the investigator's opinion, may put the patient at risk, may confound the study results, or may interfere with the patient's participation in the study.
• Clinically significant sensitivity to visible light, or has porphyria or porphyrin sensitivity.
• Exposure to ultraviolet radiation (UVB phototherapy, sun tanning salons) within the last 30 days.
• Patients with a washout period for topical treatments for their acne of less than 14 days. Medicated cleansers may be used during the washout period and stopped before the treatment.
• Patients with a washout period for oral antibiotics for treatment of their acne of less than 1 month.
• Patients with a washout period for oral isotretinoin of less than 6 months.
• Patients with a beard or other facial hair that might interfere with study assessments.