The conventional treatment in warm-antibody dependent autoimmune haemolytic anaemia (AIHA) is high-dose glucocorticoid, but in more than half of the patients, haemolytic activity will recur after end of treatment or during the gradual reduction in dose of the drug. As a result, many patients will finally be splenectomized or be treated with long-term glucocorticoids or other immunosuppressive drugs as azathioprine or cyclophosphamide. Recent studies have shown however, that some patients will respond to treatment with the chimeric anti-CD 20 antibody Rituximab and is some cases, the response is permanent. In most of the studies, Rituximab has been used in refractory disease or at least as second line treatment. In this study, patients with AIHA are randomized to receive either high-dose prednisolone with gradual reduction in dose over 2-3 months alone or in combination with Rituximab 375 mg/m2 once a week for 4 weeks. The efficacy of Rituximab will be evaluated by a comparison of the patients in the two treatment arms. The primary treatment goal is a reduction in the number of patients who obtain long-term complete or partial remission. The secondary treatment goal is a reduction in patients who will be splenectomised or receive other immunosuppressive drugs. Finally a comparison of side effects of the treatments will take place.

Inclusion Criteria:

• Age 18 years or over
• Clinical and biochemical signs of haemolytic anaemia
• Positive Coombs test with anti-IgG on its own or with anti-CD3d
• Adequate contraceptive measures (intrauterine device, contraceptive pill or gestagen deposit) for women of childbearing potential

Exclusion Criteria:

• Performance status > 2
• Previous treatment with Rituximab
• Other immune suppressive or anti neoplastic treatment including prednisolone within 3 months
• Auto immune haemolytic anaemia within 6 months
• Other serious disease
• Pregnant women and nursing mothers. Adequate contraceptive measures must be taken for the duration of the study.
• Contraindication for treatment with Rituximab, i.e. patients that develop hypersensitivity/allergy to the contents of the drug or have antibodies against murine proteins.
• Active infection which requires antibiotic treatment