Gammaked Background

General ITP Information

WHAT IS ITP?

ITP, also known as idiopathic thrombocytopenic purpura, immune thrombocytopenic purpura and autoimmune thrombocytopenic purpura1, is a clinical syndrome in which a decreased number of circulating platelets manifests as a bleeding tendency, easy bruising, or extravasation of blood from capillaries into skin and mucous membranes.2 

ITP is primarily a disease of increased peripheral platelet destruction, with most patients having antibodies to specific platelet membrane glycoproteins.1 Acute ITP typically follows an acute infection and resolves within 2 months. Chronic ITP persists for more than 6 months, often with no specific cause.1

In the United States, the incidence of ITP in adults is approximately 66 cases per 1,000,000 per year. An average estimate of the incidence in children is 50 cases per 1,000,000 per year. There are approximately 10 new cases of chronic refractory ITP per 1,000,000 per year.


 

SIGNS AND SYMPTOMS OF ITP1

Common signs and symptoms include:

  • Nonpalpable petechiae, which mostly occur in dependent regions
  • Hemorrhagic bullae on mucous membranes
  • Purpura
  • Gingival bleeding
  • Signs of bleeding in the bowel or stomach
  • Menometrorrhagia, menorrhagia
  • Retinal hemorrhages
  • Evidence of intracranial hemorrhage, with possible neurologic symptoms
  • Nonpalpable spleen
  • Spontaneous bleeding when platelet count is less than 20,000/mm

Precipitating factors include1:

  • Recent live virus immunization (childhood ITP)
  • Recent viral illness (childhood ITP)

DIAGNOSING ITP:

There is no single laboratory result or clinical finding that can establish a diagnosis of ITP; the type and severity of bleeding must be evaluated and other causes of bleeding excluded.

Alternative diagnoses that should be eliminated include3

  • Previously diagnosed or possible high risk of HIV, HCV, or other infections
  • Other Autoimmune/Immunodeficiency disorders (e.g., systemic lupus erythematosus)
  • Malignancy, lymphoproliferative disorder
  • Recent immunizations
  • Liver disease (including alcoholic liver cirrhosis)
  • Drugs (prescription or non-prescription)
    • Alcohol abuse
    • Quinine consumption
  • Exposure to environmental toxins 
  • Bone marrow diseases
    • Myelodysplastic syndromes
    • Leukemias, other malignancies
    • Aplastic anemia
    • Megaloblastic anemia
  • Recent transfusions 
  • Inherited thrombocytopenia
    • Thrombocytopenia-absent radius (TAR) syndrome
    • Radioulnar synostosis
    • Congenital amegakaryocytic thrombocytopenia
    • Wiskott-Aldrich syndrome
    • MYH9-related disease
    • Bernard-Soulier syndrome
    • Type IIB von Willebrand disease

 

TREATMENT OF ITP:

Treatment of ITP may be coordinated with a hematologist. In children, ITP often runs its course without the need for treatment. About 80% of children recover completely within 6 months.1 

Adults with platelet counts < 50,000/mm4 require treatment.

Gammaked is an approved IGIV therapy treatment for ITP. However, glucocorticoids are also used to manage ITP. IGIV is used when a rapid elevation in platelet count is needed, such as in the case of critical bleeding or in preparation for surgery.

Patients with refractory ITP, unresponsive to IGIV or glucocorticoids, may require splenectomy (removal of the spleen) if they have persistently low platelet counts or intractable bleeding.


 

ADVERSE REACTIONS OBSERVED IN ITP4:

The most common adverse reactions observed at a rate ≥ 5% in subjects treated with Gammaked for ITP were headache, vomiting, fever, nausea, back pain and rash.


References: 1. Silverman MA. Idiopathic thrombocytopenic purpura. September 2012. http://www.emedicine.com/emerg/topic282.htm. Accessed October 1, 2014. 2. Sandler SG, Bhanji R. Immune thrombocytopenic purpura. September 2012. http://www.emedicine.com/med/topic1151.htm. Accessed October 1, 2014. 3. Provan D, Stasi R, Newland AC et.al. International consensus report on the investigation and management of primary immune thrombocytopenia. Blood. 2010;115:168-186. 4. GAMMAKED [package insert]. Fort Lee, NJ. Kedrion Biopharma Inc.; 2013.