Research Article Open Access Adult Chronic Primary Immune Trombocytopenia: Safety and E fcacy of Trombopoietin Receptor Agonists and Rituximab Internal Medicine, California Institute of Behavioral Neuroscience and Psychology, Fairfeld, USA Zeina Al Achkar*, Nusrat Jahan, Cesar Peralta and Humera Batool *Corresponding author Zeina Al Achkar, Internal Medicine, California Institute of Behavioral Neuroscience and Psychology, Fairfeld, USA. E-mail: zeinaachkar2@gmail. com Received: April 07, 2021; Accepted: April 12 , 2021; Published: April 24, 2021 Journal of Dermatology Research Reviews & Reports Volume 2(2): 1-5 Introduction & Background Primary immune thrombocytopenia (ITP), one of the most common acquired autoimmune bleeding disorders characterized by immune-mediated destruction and defective platelet production, which increases the risk of bleeding [1]. The pathophysiology of ITP was considered to be due only to accelerated autoantibody- mediated platelet destruction in the reticuloendothelial system (RES), particularly in the spleen [2-3]. However, some evidence shows that ITP also results from defective platelet production [4- 5]. Persistence of ITP beyond 12 months is the defnition of chronic ITP [6]. Patients affected with ITP have increased risk of bleeding that may range from minor presentations such as petechiae and bruising to the most life-threatening and dangerous events such as intracranial hemorrhage, and diminished health-related quality of life (HRQoL) [7-8]. The primary goal of the management of chronic ITP is to increase and maintain platelet count in a safe range to avoid life-threatening complications, as well as improving HRQoL. The frst-line of therapies included glucocorticoids, intravenous immunoglobulins (IVIG), or intravenous anti-D [6,9- 10]. However, relapse or failure to respond to these may urge to the use of other pharmacological agents and modalities, which can include a wide variety of therapies, such as splenectomy, azathioprine, rituximab, vincristine, danazol, vinca alkaloids, and cyclophosphamide [11-12]. The second-line therapies are associated with high costs, severe adverse effects, and toxicities [11-12]. Splenectomy is the treatment that has the highest rates of response in patients with chronic ITP (65%) [13-14]. However, the inability to reliably predict whether an individual patient will respond, as well as the risk associated with a surgical procedure like splenectomy in both the short and long term including bleeding and infection, lead many patients and physicians to defer surgery in favor of medical therapy. The overall prognosis of ITP is good, with less than two percent mortality, but the latter can rise to 10% for a subgroup of patients with chronic severe ITP refractory to splenectomy. Recent consensus statements and guidelines recommend thrombopoietin receptor (TPO-R) agonists as second- and third-line agents for ITP treatment [6-10]. There are two TPO-R agonists, the non- peptide Eltrombopag and the peptide Romiplostim. Both are effective in increasing platelet counts with relatively low toxicity. Both TPO-R agonists stimulate megakaryocytes, induce their maturation and proliferation, and thereby increase platelet counts in approximately 80% of ITP patients in randomized controlled trials [15-16] and 74% of the patients treated in real-life practice [17]. On the other hand, rituximab is a treatment of choice for many patients with chronic ITP. Various autoimmune diseases, including ITP, are treated with Rituximab, which is a chimeric anti-CD20 monoclonal autoantibody [18-19]. Binding to CD20 induces profound albeit transient B-cell depletion by producing antibody-dependent cytotoxicity, complement activation, and/or induction of apoptosis [20]. Rituximab reduces platelet antibodies level by depleting B cells, resulting in a 60% improvement in platelet count of patients with immune thrombocytopenia (ITP). Despite the proved effectiveness of both TPO-R agonists and rituximab in the treatment of chronic ITP that is refractory to frst-line therapy with corticosteroids, IVIG, or anti-D, there is no evidence to guide the second-line treatment for those patients. The choice of second-line agent for ITP that is refractory to frst- line regiments has been a subject of debate. Since there are no evident guidelines that sequence the second-line treatments of ITP, deciding which drug would provide optimal results is challenging. TPO-R agonists and Rituximab are essential components of second-line therapies. Although both drugs have proven relatively similar effcacy, the decisions should be based on multiple additional factors, including the safety of the drug, unfavorable effects, and costs. However, comparative evidence of TPO-R agonists and Rituximab is narrowed, which highlights a gap in the literature regarding effcacy, safety, and side effects. Given the importance of this topic, and the life-threatening risks imposed on patients suffering from chronic ITP, literature review will illustrate a comparison between TPO-R agonists and Rituximab in terms of effcacy, safety, and side effects. Methods The focus of this literature review is to compare the second-line ITP treatments, TPO-R agonists, and Rituximab, in terms of effcacy, safety, and side effects. English language papers published within the last ten years were identifed through searches of the PubMed database using the MeSH keywords idiopathic thrombocytopenic purpura, therapy, drug therapy. Studies were limited to human J Dermatol Res Rev Rep 2021 ISSN: 2754-494X