Avatrombopag is currently in clinical development for the treatment of chronic immune thrombocytopenia (ITP) in patients who have had an insufficient response to previous treatment. ITP is an auto-immune disease that arises when the body’s immune system attacks platelet cells resulting in a decreased number of platelets (platelet count). Platelets help blood to clot following damage to a blood vessel wall so if there is a decreased number of platelets there is an increased risk of frequent bleeding or severe bleeding. This results in the symptoms associated with ITP such as petechial (pin prick rash of blood spots), bruising, nosebleeds, gum bleeds, fatigue and heavy periods.
Avatrombopag is given as an oral tablet and works by mimicking the action of a hormone called thrombopoietin (TPO) which is responsible for causing pre-curser cells to mature into platelets. Avatrombopag binds to TPO receptors resulting in increased platelet production and increased platelet count. Results from clinical studies have demonstrated that avatrombopag is safe and efficacious. If licensed, avatrombopag could offer an additional treatment option for patients with chronic ITP who have had limited response to previous therapy.