Inclusion criteria

• Medical diagnosis of CTCL, and positivity for the CD4 receptor.
• Late stage CTCL.
• Have received at least one prior anti-cancer therapy with inadequate effect.
• WHO performance status 0,1 or 2
• Male or female, age 18 or older.
• Signed informed consent.

Exclusion Criteria

• Certain rare types of CTCL.
• Previous treatment with other anti-CD4 medications.
• More than two previous treatments with systemic chemotherapy.
• Certain anti-psoriasis or anti-cancer therapies within the last 4 weeks before entering this trial.
• Some types of steroid treatments less than two weeks before entering the trial.
• Prolonged exposure to sunlight or UV light during the trial.
• Other cancer diseases, except certain skin cancers or cervix cancer.
• Chronic infectious disease requiring medication.
• Certain serious medical conditions, including kidney or liver disease, some psychiatric illnesses, and stomach, lung, heart, hormonal, nerve or blood diseases.
• Certain laboratory values which are too high or too low.
• HIV positivity.
• Pregnant or breast-feeding women.
• Women of childbearing age who are unable or unwilling to use an IUD or hormonal birth control during the whole trial.
• If you are participating in another trial with a different new drug 4 weeks before you enter this trial.