High-dose Dexamethasone Therapy as the Initial Treatment for Idiopathic Thrombocytopenic Purpura: Protocol for a Multicenter, Open-label, Single Arm Trial

High-dose dexamethasone therapy as the initial treatment for idiopathic thrombocytopenic purpura

There is a controversy which short term high dose dexamethasone therapy (HDD) or standard dose prednisolone therapy as the initial treatment leads to long term efficacy in idiopathic thrombocytopenic purpura (ITP) patients. We conducted a multicenter, prospective trial to determine the efficacy and safety of short-term HDD in ITP patients aged 18-80 years with platelet counts of < 20 × 10⁹/l, or < 50 × 10⁹/l and bleeding symptoms. The primary endpoints are the proportion of complete response (CR) plus partial response (R) on day 180 after the completion of the 46-day HDD. Twenty-three patients were enrolled. Test for Helicobacter pylori (H. pylori) was positive for 6 patients and negative for 17 patients. In positive patients, 5 were received successful H. pylori eradication therapy. The proportion of CR + R was 60.9% (14/23) with 90% confidence interval of 41.7-77.8%. For patients with positive H. pylori and successful eradication, the proportion of CR + R was 80.0% (4/5). There was one grade 4 adverse event. Although we have enrolled relatively old, severe ITP patients with a median age of 63 years in this study, the efficacy was comparable to the reported clinical trials with HDD therapy.

Therapeutic effects of rituximab combined with cyclophosphamide on refractory idiopathic thrombocytopenic purpura

Therapeutic effects of rituximab combined with cyclophosphamide on refractory idiopathic thrombocytopenic purpura (ITP) were investigated. We retrospectively analyzed 249 patients with refractory ITP who were admitted to Qingdao Hiser Medical Group between March 2013 and March 2017. Curative effects of patients treated with rituximab, cyclophosphamide, and combination therapy were observed and the changes of platelet count, PA IgG, and lymphocyte CD20 before and after treatment, as well as the incidence of adverse reactions after treatment, were compared. There was no significant difference in the expression of lymphocyte CD20, PA IgG and platelet count among the three groups of refractory ITP patients before treatment (P>0.05). After treatment, the expression levels of CD20 and PA IgG in lymphocytes were significantly downregulated, and platelet counts significantly increased in the three groups (P<0.05). After treatment, CD20 and PA IgG levels in combined therapy group were significantly lower, and platelet count was significantly higher, than those in the rituximab and cyclophosphamide groups (P<0.05). Also, after rituximab treatment, the expression levels of CD20 and PA IgG in lymphocytes were significantly lower than those in cyclophosphamide group (P<0.05), and platelet count was higher than that in cyclophosphamide group (P<0.05). After treatment, the total effective rate in combined therapy group was higher than that in the rituximab and cyclophosphamide group (P<0.05). Total effective rate of rituximab group was significantly higher than that of cyclophosphamide group (P<0.05). The incidence of adverse reactions in combined therapy group was 14.29% (12/84), which was significantly lower than that in cyclophosphamide group (40.70%, 35/86, P<0.05) and rituximab group (29.11%, 23/79, P<0.05). The application of rituximab combined with cyclophosphamide in the treatment of refractory ITP can improve patients clinical symptoms. The efficacy of this technique is promising with no serious adverse reactions. This technique should be popularized in clinical practice.

CB2 Receptor Stimulation and Dexamethasone Restore the Anti-Inflammatory and Immune-Regulatory Properties of Mesenchymal Stromal Cells of Children with Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by antibody-mediated platelet destruction, with a complex and unclear pathogenesis. The impaired immunosuppressive capacity of mesenchymal stromal cells in ITP patients (ITP-MSCs) might play a role in the development of the disease. Correcting the MSC defects could represent an alternative therapeutic approach for ITP. High-dose dexamethasone (HD-Dexa) is the mainstay of the ITP therapeutic regimen, although it has several side effects. We previously demonstrated a role for cannabinoid receptor 2 (CB₂) as a mediator of anti-inflammatory and immunoregulatory properties of human MSCs. We analyzed the effects of CB₂ stimulation, with the selective agonist JWH-133, and of Dexa alone and in combination on ITP-MSC survival and immunosuppressive capacity. We provided new insights into the pathogenesis of ITP, suggesting CB₂ receptor involvement in the impairment of ITP-MSC function and confirming MSCs as responsive cellular targets of Dexa. Moreover, we demonstrated that CB₂ stimulation and Dexa attenuate apoptosis, via Bcl2 signaling, and restore the immune-modulatory properties of MSCs derived from ITP patients. These data suggest the possibility of using Dexa in combination with JWH-133 in ITP, reducing its dose and side effects but maintaining its therapeutic benefits.