A national, multicentre, prospective, randomised, double-blind, phase III study in 2 parallel groups of isotretinoin versus placebo in patients presenting papular-pustular rosacea resistant to standard therapy. A non-balanced group (2 isotretinoin /1 placebo) design was selected since, given the nature of the study disease, fewer patients will receive the placebo than active isotretinoin.

Treatment duration for each patient : 4 months, with monthly evaluation Follow-up at 2 months and 4 months for patients responsive after 4 months of treatment.

Inclusion Criteria:

• Adult
• Patients presenting papular-pustular rosacea (characterised by at least 8 lesions (papules and/or pustules)
• resistant for at least 3 months in the last two years to standard treatment comprising systemic antibiotics (cyclins) with or without topical therapy
• Full compliance with a two-week wash-out period for all other topical and systemic treatments for rosacea at the time of selection
• For women of childbearing age, use of a minimum of one "effective" contraceptive method for at least one month and willingness to continue using an effective contraceptive method continuously throughout the study duration and for at least one month after the end of treatment.
• Women of childbearing age must provide consent for pregnancy testing before the start of treatment, monthly throughout treatment and 5 weeks after the end of treatment.
• Negative pregnancy test results from within the last 3 days (for female subjects of childbearing age)
• No laboratory abnormalities in standard tests
• Social Security medical cover
• Provision of written and dated informed consent to take part in the study

Exclusion Criteria:

• Patients already receiving isotretinoin for rosacea or within the last 12 months for acne
• Patients presenting perioral dermatitis
• Patients presenting miliary lupoid
• Patients presenting cortisone-induced rosacea
• Pregnant or breast-feeding women
• Patients with repeated and habitual heavy physical activity
• Patients with known hepatic impairment presenting cytolysis as attested by laboratory results
• Patients presenting hyperaemia
• Patient presenting hypervitaminosis A
• Patients with a history of hypersensitivity to isotretinoin
• Patients with allergy to soy oil
• Patients on tetracycline
• Patients with depression treated at the time of selection
• Patients currently taking part in having taken part in another study in the last 3 months prior to inclusion in the present study
• Patients protected by law (under guardianship or trusteeship)
• Patients unable to comply with the study requirements