WinRho SDF for ITP: Cangene announces new safety information

Mar 27 2010

Association of WinRho(R) SDF (Rho(D) Immune Globulin (Human)) with Intravascular Hemolysis in the Treatment of Immune Thrombocytopenic Purpura (ITP)

Cangene Corporation, in consultation with Health Canada, is informing Canadian patients and healthcare professionals of important new safety information concerning the use of WinRho(R) SDF (Rho (D) Immune Globulin (Human)) for the treatment of immune thrombocytopenic purpura, also called immune thrombocytopenia, or ITP. WinRho(R) SDF belongs to a group of biological medicines derived from human plasma known as immunoglobulins. It is administered in hospitals by infusion through the veins.

There have been rare reports of a serious side effect, called intravascular hemolysis (IVH), following WinRho(R) SDF treatment for ITP. IVH occurs when red blood cells are broken down in the blood vessels, which can cause serious illness. Symptoms of IVH can occur hours to days after WinRho(R) SDF treatment. If you experience any of the following symptoms after receiving WinRho(R) SDF, you should call your doctor immediately:

- back pain, - discoloured or darkened urine, - decreased urine production, - jaundice (yellow colour in skin or eyes), - swelling, - shortness of breath.

Between March 1995 and March 2009 worldwide there were 180 serious case reports of suspected and/or confirmed IVH reported to the manufacturer, Cangene Corporation. Of these, 58 case reports were considered definite IVH, and, although other factors were involved, 17 of these patients died. Thirteen of the patients who died were older than 65, and 15 of them also had other medical conditions which may have made the outcome worse. In Canada, 11 cases of suspected IVH have been reported to Health Canada. Two of these patients died.

New exclusion criteria (known as contraindications) and instructions for patient monitoring have been added to the WinRho(R) SDF prescribing information. The following patients SHOULD NOT be treated with WinRho(R) SDF for ITP:

- Patients who have leukemia or lymphoma (blood cancers) - Patients who have infections with Epstein-Barr virus or with hepatitis C - Patients who are older than 65 and who have other conditions which make them more likely to develop hemolysis, or to develop further health problems resulting from hemolysis - Patients who may be likely to develop hemolysis, as a result of diseases such as autoimmune hemolytic anemia (Evan's Syndrome), Systemic Lupus Erythematosus (SLE) or anti-phospholipid antibody syndrome (APS)

In addition, patients receiving WinRho(R) SDF for ITP should be monitored by their healthcare providers for 8 hours after receiving their treatment, and their urine should be tested for the presence of blood before the infusion and 2, 4 and 8 hours after the infusion.