• Increase of platelet count >/= 50,000/µl [ Time Frame: 5 days ] [ Designated as safety issue: No ]
  
• Time taken for the platelet count to reach >/= 50,000/µl [ Time Frame: 21 days ] [ Designated as safety issue: No ]
  
• The length of time the platelet count remains >/= 50,000/µl [ Time Frame: 21 days ] [ Designated as safety issue: No ]
  
• The maximum platelet level [ Time Frame: 21 days ] [ Designated as safety issue: No ]
  
• Regression of bleeding episodes during the first 10 or 14 days [ Time Frame: 14 days ] [ Designated as safety issue: Yes ]
  

• Changes in vital signs and clinically relevant changes in laboratory parameters after the infusions, including renal function (creatinine levels) [ Time Frame: 3 months ] [ Designated as safety issue: Yes ]
  
• Viral safety through the investigation of patients virology status (HAV, HBV, HCV and HIV) and assessment of alteration in their liver function [ Time Frame: 3 months ] [ Designated as safety issue: Yes ]
  
• Nature, severity and frequency of adverse reactions during and after infusions [ Time Frame: 30 days ] [ Designated as safety issue: Yes ]
  

To determine if IGIV3I Grifols is a consistently effective treatment in patients diagnosed with immune thrombocytopenic purpura with respect to:

1. Increase of platelet count > 50,000/µl (primary objective).
2. Time taken for the platelet count to reach > 50,000/µl.
3. The length of time the platelet count remains > 50,000/µl.
4. The maximum platelet level.
5. Regression of bleeding episodes during the first 10 or 14 days.

To determine if IGIV3I Grifols is safe with respect to:

1. Nature, severity and frequency of adverse reactions during and after infusions.
2. Changes in vital signs and clinically relevant changes in laboratory parameters after the infusions, including renal function (creatinine levels).
3. Viral safety through the investigation of patients virology status (HAV, HBV, HCV and HIV) and assessment of alteration in their liver function.

Inclusion Criteria:

1. Be aged between 18 and 82 at the time of written consent.

2. Have confirmed diagnosis of chronic ITP and fulfil all the following criteria:

   • irrelevant history except for the symptoms of bleeding,
   • pattern of bleedings associated with platelet disorders,
   • physical examination irrelevant for the ITP, except for the signs of bleeding,
   • isolated thrombocytopenia in the blood count; apart from thrombocytopenia, the blood count is normal for the patient's age, or if abnormal, readily explained,
   • peripheral blood smear consistent with ITP: thrombocytopenia with platelets of normal size or slightly larger than normal, with absence of platelet clumps and giant platelets; normal red blood cell and white blood cell morphology,
   • confirmed diagnosis of immune thrombocytopenic purpura or, when any abnormal finding is present, additional diagnostic evaluation excludes other causes of thrombocytopenia.
   • Previous known diagnosis of ITP for at least 6 months.

3. Be in an acute phase at the moment of infusion and fulfil at least one of the two following criteria:

   • platelet count <10,000/µl,
   • platelet count between 10,000-20,000/µl and at least one of the following clinical situations:
   • asymptomatic patients that, otherwise, used to maintain a platelet count >30,000/µl,
   • asymptomatic patients who have major risk factors for bleeding,
   • patients with spontaneous cutaneous bleeding symptoms,
   • patients with spontaneous mucous membrane bleedings.
4. Have read the patient information and consent sheet, agreed to participate in the trial, and signed the consent sheet.
5. Be expected to receive treatment over 5 days and follow-up for 3 months.

Exclusion Criteria:

1. Have immune thrombocytopenia secondary to other pathologies or drug mediated thrombocytopenia.
2. Have a known diagnosis of other autoimmune diseases, established in the medical history and laboratory findings with positive results for the determination of antinuclear antibodies, anti-cardiolipin antibodies, lupus anticoagulant or direct Coombs test.
3. Present important active bleeding due to other reasons apart from the ITP.
4. Exhibit an identifiable alternative cause of their thrombocytopenia, such as splenomegaly, family thrombocytopenia, bacteraemia, sepsis or active infection requiring or not therapy.
5. Are presenting renal dysfunction.
6. Have non-controlled arterial hypertension.
7. Have documented liver cirrhosis or any hepatic disorder with ALT levels 2.5 times or more than the normal upper limit or bilirubin greater than 2 mg/dl.
8. Are presenting a cardiac disease including a history of coronary artery disease, angina pectoris or congestive heart failure.
9. Present known infection due to HIV or HCV.
10. Have been previously treated with IVIG or anti-D immunoglobulin being unresponsive.
11. Have a history of serious adverse reactions or non-serious but frequent adverse reactions to IVIG preparations or other products derived from blood.
12. Have known allergies to any IGIV3I Grifols components, such as D-sorbitol.
13. Are simultaneously participating in other clinical studies or have received an investigational drug in the 3 months prior to the start of the study.
14. Have conditions that might affect patient compliance.
15. Are unable to provide a storage serum sample just before the first dose of IGIV3I Grifols.
16. Are pregnant or nursing an infant child or unwilling to practice adequate birth control in 1-month period after the first infusion in the study.