In a prospective pilot study the investigators showed that low doses of IL2 could be beneficial for severe AA inducing a long lasting regrowth in 4 out of the 5 patients treated.

The objective of this study is to compare the long term efficacy of low doses of IL2 versus placebo in a multicenter prospective randomized double blind study.

Inclusion Criteria:

• Of more than 18 years old,
• Affiliated to the social security system,
• Clinical diagnosis of alopecia areata,
• 50 % of the surface of the scalp affected
• Last flaire started less than one year
• Alopecia areata resisting to at least 1 systematic treatment including phototherapy (UVB or PUVA), general corticosteroid therapy or methotrexate
• Signature of the informed consent

Exclusion Criteria:

• Pregnancy or refusal of contraception at the women old enough to procreate,
• Refusal of contraception at the men
• Local treatment (dermocorticoïdes, minoxidil) or systematism (oral corticosteroid therapy, méthotrexate or the other immunosuppresseur) since less than 2 less,
• Evolutionary autoimmune cancer or disease or in forgiveness
• Excessive grip(taking) of alcohol (upper to 3 glasses of wine a day or one pre-lunch drink a day)
• Seropositivity VHC, VHB, or HIV
• Patient presenting a severe renal and/or hepatic insufficiency,
• Presenting patient one zoned, the chicken pox, the herpes, the tuberculosis, an evolutionary infectious disease, a respiratory failure …
• Vulnerable person (nobody under guardianship minor(miner), adults, deprived of freedom)
• IC in the treatment(processing) by IL-2R
• Presenting a contraindication to ProleukinR