A Phase 3 Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Efficacy and Safety of Avatrombopag for the Treatment of Chemotherapy-Induced Thrombocytopenia in Patients with Solid Tumors

Background: Chemotherapy-induced thrombocytopenia (CIT) is a common complication in cancer patients receiving myelosuppressive chemotherapy. Not only can it increase the risk of bleeding, but it also complicates cancer treatment due to chemotherapy delays, dose reductions, and discontinuation, potentially resulting in sub-optimal treatment outcomes. There are currently no FDA approved medications available to manage CIT in the US and Europe. While platelet transfusions are used to rescue patients with very low platelet levels, they are associated with risks of viral and bacterial infections. Avatrombopag is an orally administered thrombopoietin (TPO) receptor agonist that mimics the biologic effects of TPO, resulting in increased platelet production. Avatrombopag is approved for the treatment of thrombocytopenia in patients with chronic liver disease (CLD) scheduled to undergo a procedure, and in adults with chronic immune thrombocytopenia (ITP) that have had an insufficient response to a prior therapy. Pre-clinical data as well as clinical data in patients with CLD and ITP suggest that Avatrombopag is a promising candidate for treatment of thrombocytopenia of diverse etiologies, including CIT. Study design and method: This is a phase 3 randomized, double-blind, placebo-controlled, multi-national (United States, Russia, Ukraine, Poland, China, Serbia, Hungary), study evaluating the efficacy and safety of oral Avatrombopag for the treatment of CIT in 120 adult patients with NSCLC, SCLC, bladder, or ovarian cancer (NCT03471078). To be eligible for the study, patients must have experienced severe thrombocytopenia (platelet counts (PC) 2 prior lines of myelosuppressive chemotherapy, prior history of CIT (PC