Inclusion Criteria:

• GFR≥25ml/min/1.73m2 calculated by the MDRD equation
• Urinary total protein: creatinine ratios >200mg/mmol derived from the average of 2 first morning voids taken during screening period
• Biopsy confirmed as idiopathic FSGS by a central reviewer
• Treatment resistance. NOTE:Patients to have received minimum 6 week course of steroids or immunosuppressant
• If receiving treatment with an ACEi and/or ARB dose to be stable for a minimum of 4 weeks prior to randomization
• Influenza vaccine (according to season)
• Negative screening per American Cancer Society (ACS) 2003 guidelines, as appropriate to patient demographics and clinical status

Exclusion Criteria:

• Secondary FSGS
• steroid resistant patients who are unable to reduce their steroid dose to <10mg/day of prednisolone or equivalent 4 weeks prior to study dosing day
• Positive serology for serious infections (including but not limited to infection with Hep B or C, HIV)
• Concomitant illnesses:Diabetes Type I; Cardiac or Hepatic disease, HIV; Cancer, precancerous state (eg familial adenomatous polyposis; Any condition requiring treatment with other immunosuppressant drugs within 4 weeks prior to dosing day or during the course of the study
• Pre-existing oral-pharyngeal disease (dental carries and other minor dental disease are acceptable)
• Haemoglobin level of <9.0g/dL prior to dosing
• Treatment with coumadin, anti-vitamin K analogues or low molecular weight heparins. Patients must have stopped treatment a minimum of four weeks prior to receiving study medication.
• Patients requiring ongoing treatment with non-steroidal anti-inflammatory drugs (NSAIDs). Patients must have stopped treatment a minimum of four weeks prior to receiving study medication.
• Patients who have had surgery/fracture within 3 months prior to dosing day
• History of cancer unresolved within 5 years prior to screening or a known precancerous state; or any form of skin cancer either current or past history
• Women who are pregnant, lactating or who plan to become pregnant within 4 months of infusion
• Women of childbearing potential unless taking medically acceptable contraceptive
• Men with female partners of childbearing potential unless they are taking medically acceptable contraceptive precautions
• Use of any investigation drug administered as part of a clinical trial within 4 weeks prior to commencing screening
• Other clinically significant, uncontrolled medical condition that in the investigator's opinion may interfere with the assessment or follow-up
• Active ethanol or drug abuse, excluding tobacco use
• Electrocardiogram (ECG) abnormalities considered to be clinically significant at screening
• Unable to comply with the requirements of the study
• Active thrombophlebitis, thromboembolism, hypercoagulability states, bleeding, or use of anticoagulation therapy (including anti-platelet agents). Patients with a history of deep venous thrombosis may participate if successfully treated, completely resolved, and no treatment has been given for >4 months.