You will be watched carefully before, during, and after each CT-011 or rituximab infusion in case you experience any side effects to the drug. You will be given Benadryl (diphenhydramine) and Tylenol (acetaminophen) about 30 to 60 minutes before each infusion in order to lower the risk of possible side effects. If the doctor thinks it is needed, you may also be given other drugs such as hydrocortisone or prednisone (also known as corticosteroids) to help lower the risk of possible side effects. If the side effects become intolerable, and the doctor thinks it is necessary, the infusion may be stopped for a short time or stopped completely.