Study With Modafinil in Patients Treated With Docetaxel-Based Chemotherapy for Metastatic Breast or Prostate Cancer (MOTIF)

Inclusion criteria: * Treatment with q3w (every three weeks) docetaxel-based chemotherapy for metastatic breast or prostate cancer at a minimum dose of 50 mg/m2 * Completed at least two cycles of chemotherapy and intention to treat the patient with at least two further cycles of docetaxel-based chemotherapy * Fatigue \> or = to 4 on the MD Anderson Symptom Inventory fatigue assessment scale during the previous docetaxel chemotherapy cycle * SPHERE somatic (SOMA) subscale score \> or = to 3 * Worsening of fatigue after commencement of docetaxel chemotherapy * Haemoglobin (Hb)\> or = to 10 g/dL within two weeks before randomisation Exclusion criteria: * Unable to complete the MD Anderson Symptom Inventory fatigue assessment scale or Functional Assessment of Chronic Illness Therapy-Fatigue Quality of Life survey * Require docetaxel chemotherapy dose reduction to less than 50 mg/m2 * History of chronic fatigue condition * Uncontrolled hypertension (blood pressure \> or = to 150/90 mm Hg * Known hypersensitivity / intolerance to modafinil or any of the excipients * Pregnant women * Psychological, familial, sociological, or geographical conditions that do not permit treatment or medical follow-up and / or prohibit compliance with the study protocol * Any serious concomitant illness that, in the opinion of the Investigator, would preclude a patient from participating in the study * Non-English speaking The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.