Immune Thrombocytopenia (ITP) is a blood disorder in which the immune system produces antibodies that attack and destroy the body's own blood platelets. The Panzyga Study is looking at a potential medicine (experimental drug) to see if it can result in increasing platelet counts and may potentially treat ITP. You will be infused with the experimental drug once or twice during the treatment period and will be followed up for 32 days. Testing will include blood tests, urine tests, pregnancy tests and physical exams. You may be able to take part in the study if you are below 18 years of age and have been diagnosed with chronic ITP.