Cyclosporin A as an immunosuppressive treatment modality for patients with refractory autoimmune thrombocytopenic purpura after splenectomy failure

Rituximab resistance in ITP and beyond

The pathophysiology of immune thrombocytopenia (ITP) is complex and encompasses innate and adaptive immune responses, as well as megakaryocyte dysfunction. Rituximab is administered in relapsed cases and has the added benefit of inducing treatment-free remission in over 50% of patients. Nevertheless, the responses to this therapy are not long-lasting, and resistance development is frequent. B cells, T cells, and plasma cells play a role in developing resistance. To overcome this resistance, targeting these pathways through splenectomy and novel therapies that target FcγR pathway, FcRn, complement, B cells, plasma cells, and T cells can be useful. This review will summarize the pathogenetic mechanisms implicated in rituximab resistance and examine the potential therapeutic interventions to overcome it. This review will explore the efficacy of established therapies, as well as novel therapeutic approaches and agents currently in development.

More about the combination of rituximab, cyclosporine and dexamethasone in the treatment of chronic ITP. A useful option on an environment with limited resources

Treatment of chronic primary immune thrombocytopenia (ITP) is challenging especially with limited resources and therapy-related complications. This prospective interventional study assessed the efficacy and safety of triple therapy(TT4); a combination treatment of oral dexamethasone 40 mg for days1-4, oral cyclosporine A 2-3 mg/kg daily for 28 consecutive days and intravenous rituximab 100 mg for days7,14,21 and 28 among 40 patients with ITP who failed previous 2 or more treatment options. Our aim was to maintain platelet count ≥ 30 X 10⁹/L without any obvious bleeding at any point in the study. Platelet counts were assessed weekly for a month then monthly for 2 years to evaluate the long-term response. TT4 was well tolerated and induced a good response with a significant increase in the mean platelet count after the 1^st, 2^nd, 3^rd, and 4^thweek compared to the baseline. Patients with mean platelet count ≥ 30 X 10⁹/L at the 6^th month were 75% (30/40 patients). Treatment free survivals (TFS) at 12 and 24 months were 93.3% (28/30 patients) and 80% (24/30 patients) respectively. TT4 is an effective treatment option that maintained platelet count in the desired level and induced a higher sustained response, especially in an environment with limited resources.

How I treat refractory immune thrombocytopenia

This article summarizes our approach to the management of children and adults with primary immune thrombocytopenia (ITP) who do not respond to, cannot tolerate, or are unwilling to undergo splenectomy. We begin with a critical reassessment of the diagnosis and a deliberate attempt to exclude nonautoimmune causes of thrombocytopenia and secondary ITP. For patients in whom the diagnosis is affirmed, we consider observation without treatment. Observation is appropriate for most asymptomatic patients with a platelet count of 20 to 30 × 109/L or higher. We use a tiered approach to treat patients who require therapy to increase the platelet count. Tier 1 options (rituximab, thrombopoietin receptor agonists, low-dose corticosteroids) have a relatively favorable therapeutic index. We exhaust all Tier 1 options before proceeding to Tier 2, which comprises a host of immunosuppressive agents with relatively lower response rates and/or greater toxicity. We often prescribe Tier 2 drugs not alone but in combination with a Tier 1 or a second Tier 2 drug with a different mechanism of action. We reserve Tier 3 strategies, which are of uncertain benefit and/or high toxicity with little supporting evidence, for the rare patient with serious bleeding who does not respond to Tier 1 and Tier 2 therapies.

Refractory immune thrombocytopenia. Successful treatment with repeated cyclosporine A: two case reports

Treatment of chronic, severe refractory immune thrombocytopenia after splenectomy is difficult. Only less data exist on clinical use of cyclosporine A (CyA) in the management of refractory ITP. In this report, we describe two cases in which standard immunosuppressive therapy, other immunosuppression including cyclosporine A or splenectomy had no therapeutic effect. Even after splenectomy, recommended procedures were inefficient and critical thrombocytes count persisted. After repeated administration of cyclosporine A which had been ineffective prior to splenectomy; however, both patients achieved long-term complete remission of the ITP. Side effects of CyA were moderate. The presented cases have confirmed the potential therapeutic effect of CyA in refractory post-SE ITP.

Immunosuppressive treatment combined with nucleoside analog is superior to nucleoside analog only in the treatment of severe thrombocytopenia in patients with cirrhosis associated with hepatitis B in China: A multicenter, observational study

No effective treatment has been identified for patients of liver cirrhosis (LC) associated with hepatitis B virus (HBV) and severe thrombocytopenia. We aimed to explore the effectiveness and safety of low-dose prednisone or cyclosporine A (CsA) combined with nucleoside analog (NA) in patients with severe thrombocytopenia associated with HBV-related LC. We included 145 consecutive compensated HBV-associated LC patients with severe thrombocytopenia between 1 January 2006 and 31 December 2013. We divided the patients into three groups by treatment strategy, including NA only (n = 57), NA plus prednisone (n = 46), and NA plus CsA (n = 42). We analyzed the platelet counts, bleeding events, liver function, replication of HBV, and outcomes in each group. At all time points during this observation, the platelet counts in prednisone or CsA group were higher than those in the NA only group. There are significant differences in the cumulative rates of bleeding events among the three groups. The platelet counts and treatment were factors associated with bleeding events in multivariate analysis. The differences in HBV-DNA negative rates, HBV-DNA elevated rates, normal serum alanine transaminase rates, serum alanine transaminase elevated more than two times the baseline rates, and HBeAg seropositive conversion ratio among the groups did not reach statistical significance. The adverse events in our study were, in general, mild and balanced among the three treatment groups. Treatment with low-dose prednisone or CsA plus NA could elevate the platelet counts and reduce the risk of bleeding events in HBV LC with severe thrombocytopenia.

Cost effectiveness of romiplostim for the treatment of chronic immune thrombocytopenia in Ireland

BACKGROUND

Romiplostim, a thrombopoietin receptor agonist (TPOra), is a second-line medical treatment option for adults with chronic immune thrombocytopenia (ITP). Clinical trials have shown that romiplostim increases platelet counts, while reducing the risk of bleeding and, in turn, the need for costly rescue medications.

AIMS

The objective of this study was to assess the cost effectiveness of romiplostim in the treatment of adult ITP in Ireland, in comparison with eltrombopag and the medical standard of care (SoC).

METHODS

A lifetime treatment-sequence cost-utility Markov model with embedded decision tree was developed from an Irish healthcare perspective to compare romiplostim with eltrombopag and SoC. The model was driven by platelet response (platelet count ≥50 × 10(9)/L), which determined effectiveness and progression along the treatment pathway, need for rescue therapy (e.g. intravenous immunoglobulin [IVIg] and steroids) and risk of bleeding. Probability of response, mean treatment duration, average time to initial response and utilities were derived from clinical trials and other published evidence. Treatment sequences and healthcare utilization practice were validated by Irish clinical experts. Costs were assessed in <euro> for 2011 and included drug acquisition costs and costs associated with monitoring patients and management of bleeding, as available from published Irish reimbursement lists and other relevant sources. Deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

Romiplostim treatment resulted in an average of 20.2 fewer administrations of rescue medication (IVIg or intravenous steroids) over a patient lifetime than eltrombopag, and 29.3 fewer rescue medication administrations than SoC. Romiplostim was dominant, with cost savings of <euro>13,258 and <euro>22,673 and gains of 0.76 and 1.17 quality-adjusted life-years (QALYs), compared with eltrombopag and SoC, respectively. Romiplostim remained cost effective throughout a variety of potential scenarios, including short-term TPOra treatment duration (1 year). One-way sensitivity analysis showed that the model was most sensitive to variation in the cost of IVIg and use of romiplostim and IVIg. Probabilistic sensitivity analysis showed that romiplostim was likely to be cost effective in over 90 % of cases compared with eltrombopag, and 96 % compared with SoC at a willingness-to-pay threshold of <euro>30,000 per QALY.

CONCLUSIONS

Use of romiplostim in the ITP treatment pathway, compared with eltrombopag or SoC, is likely to be cost effective in Ireland. Romiplostim improves clinical outcomes by increasing platelet counts, reducing bleeding events and the use of IVIg and steroids, resulting in both cost savings and additional QALYs when compared with current treatment practices.

CD72 polymorphism associated with child-onset of idiopathic thrombocytopenic purpura in Chinese patients

Idiopathic thrombocytopenic purpura (ITP) is a disease putatively relating to abnormal immune function and auto-antiplatelet immunoglobulin. We examined whether polymorphism of CD72, an inhibitory receptor of B cells, affect the susceptibility to ITP, or associated with the clinical characteristics of ITP. A case-control study was carried out in 206 Chinese ITP patients and 169 healthy controls. The detection of variable number of tandem repeats in CD72 intron 8 was performed by polymerase chain reaction and subsequent analysis with polyacrylamide gel electrophoresis. We did not find direct association between CD72 genotypes and susceptibility to ITP. The haplotype that contained one repeat of 13 nucleotides in intron 8 (designated as *1, and haplotype containing two repeat of 13 nucleotides in intron 8 is designated as *2) was significantly associated with early first onset age (< or = 14) in ITP patients (P = 0.03). ITP patients with CD72*1\*1 and *1\*2 genotype had a 3.09-fold [95% confidence interval (CI), 1.32-7.25] and 1.98-fold (95% CI, 0.92-4.25) increased risk of appearing ITP manifestation at their childhood respectively. The haplotype CD72*1 is apparently a risk allele, whereas CD72*2 a protective allele for child-onset of ITP disease.

[Treatment of idiopathic thrombocytopenic purpura in adults]

The lack of controlled studies of the treatment of idiopathic thrombocytopenic purpura (ITP), also known as immune thrombocytopenic purpura, means that no evidence-based recommendations are available. ITP is a benign disease and severe hemorrhages are rare. Oral prednisone remains the first-line treatment. In patients with very low platelet counts and significant bleeding, intravenous immunoglobulins and high-dose oral dexamethasone may be an alternative. A validated bleeding score would help physicians use these treatments more effectively. Splenectomy remains the best curative treatment for adults with chronic ITP and platelet counts <30 x 10(9)/L after failure of the first-line treatments. Rituximab is probably the single most effective agent, as well as the least toxic, when splenectomy fails: the short-term response rate is 50% and the sustained-response rate more than 30%. Cytotoxic or other immunosuppressive agents should be reserved for patients with severe disease refractory to both splenectomy and rituximab. Thrombopoietin receptor agonists are a class of new investigational drugs for which promising results have been reported, but more data regarding long-term safety are needed.