A multicenter randomized controlled trial of recombinant human thrombopoietin treatment in patients with primary immune thrombocytopenia

Application of thrombopoietic agents in cancer therapy-induced thrombocytopenia: A comprehensive review

Cancer therapy-induced thrombocytopenia (CT-IT) is one of the most common hematological toxicities of anti-cancer therapy, often leading to treatment dose reduced, postponed, or treatment plans altered or even discontinued. Thrombopoietin (TPO) is the only key regulatory factor in platelet production, and TPO receptor is considered an ideal target for the treatment of thrombocytopenia. Thrombopoietic agents, including recombinant human thrombopoietin (rhTPO) and thrombopoietin receptor agonists (TPO-RAs), bind to different regions of the TPO receptor, activating downstream signaling pathways to increase platelet levels. In recent years, numerous studies have demonstrated the effectiveness of thrombopoietic agents in the management of CT-IT. These agents can reduce bleeding risk, decrease platelet transfusions, and maintain relative dose intensity (RDI) of anti-cancer treatments. This article provides a review of the current progress in the application of thrombopoietic agents for CT-IT management.

Thrombocytopenia in Sepsis

Platelets, traditionally known for their role in hemostasis, have emerged as key players in immune response and inflammation. Sepsis, a life-threatening condition characterized by systemic inflammation, often presents with thrombocytopenia, which at times, can be significant. Platelets contribute to the inflammatory response by interacting with leukocytes, endothelial cells, and the innate immune system. However, excessive platelet activation and consumption can lead to thrombocytopenia and exacerbate the severity of sepsis. Understanding the multifaceted roles of platelets in sepsis is crucial for developing effective therapeutic strategies. Targeting platelet-mediated inflammatory responses and promoting platelet production may offer potential avenues for improving outcomes in septic patients with thrombocytopenia. Future research should focus on elucidating the mechanisms underlying platelet dysfunction in sepsis and exploring novel therapeutic approaches to optimize platelet function and mitigate inflammation. This review explores the intricate relationship between platelets, inflammation, and thrombosis in the context of sepsis.

Insights on treatment of adult ITP: algorithm for management and role of multimodal therapy

The management of immune thrombocytopenia (ITP) is continuously evolving with the development and introduction of newer therapies and a better understanding of the disease. Corticosteroids still represent the cornerstone of first-line treatment. Patients who fail to achieve remission with a short course of corticosteroids require subsequent therapy. Most guidelines recommend starting with either a thrombopoietin receptor agonist (TPO-RA), rituximab, or fostamatinib since these agents have been investigated in randomized trials and have well-characterized efficacy and safety profiles. Patients' involvement to reach a shared decision regarding choice of therapy is essential as these treatments have different modes of administration and mechanisms of action. Less than 10% will fail to respond to and/or be intolerant of multiple second-line therapeutic options and thus be considered to have refractory ITP and require a third-line therapeutic option. Such patients may require drugs with different targets or a combination of drugs with different mechanisms of action. Combining a TPO-RA and an immunomodulatory agent may be an appropriate approach at this stage. Many studies have been conducted during the last 2 decades investigating the efficacy and safety of combinations strategies for first and later lines of therapies. Yet none of these are recommended by current guidelines or have gained wide acceptance and consensus.

Efficacy and safety of recombinant human thrombopoietin for the treatment of chronic primary immune thrombocytopenia in children and adolescents: A multicentre, randomized, double-blind, placebo-controlled phase III trial

The efficacy and safety of recombinant human thrombopoietin (rhTPO) in children and adolescent patients with chronic primary immune thrombocytopenia (ITP) remains unclear. A multicentre, randomized, double-blind, placebo-controlled phase III trial was performed. Patients aged 6-17 years, diagnosed with ITP and resistant or relapsed to corticosteroid treatment were included. For the trial, part 1 was exploratory and part 2 was the main analysis, with part 1 determining whether part 2 was stratified by age. Patients in part 1 were treated with rhTPO (the 6- to 11-/12- to 17-year-old groups; 1:1). Patients in part 2 were randomized (3:1) to receive either rhTPO treatment or placebo. Patients received rhTPO or placebo at a dose of 300 U/kg once daily for up to 14 days. A total of 68 patients were included [part 1 (12 patients), part 2 (56 patients)]. The total response rate (TRR) in part 1 was 50.0% (95% CI: 21.09%-78.91%). For part 2, the TRR was 58.5% (95% CI: 42.11%-73.68%) and 13.3% (95% CI: 1.66%-40.46%) in the rhTPO and placebo groups (FAS) respectively. The difference in TRR between the rhTPO group and placebo group was 45.2% (95% CI: 22.33%-68.08%) and 44.6% (95% CI: 21.27%-67.85%) on the FAS and per-protocol set (PPS), respectively, which indicates the superiority of rhTPO treatment.

High- vs regular-dose recombinant human thrombopoietin plus cyclosporine A in patients with newly diagnosed non-severe aplastic anemia: a retrospective cohort study

BACKGROUND

Cyclosporine A (CsA) and regular doses of recombinant human thrombopoietin (rhTPO) can accelerate platelet recovery in patients with non-severe aplastic anemia (NSAA). However, it is unclear whether CsA plus rhTPO at a higher dose can further increase the efficacy.

METHODS

Data from patients with newly diagnosed NSAA, who had been treated with CsA in combination with different doses of rhTPO between February 2021 and August 2021 at Peking Union Medical College Hospital, were reviewed. All the enrolled patients had been treated with CsA at 3-5 mg/(kg/d), and patients were further classified into high-dose (with rhTPO 30000U qd × 14 days for 2 months) group or regular-dose (with rhTPO 15000U qd × 7days for 3 months) group. The treatment response and therapy-related adverse events were compared.

RESULTS

36 patients including 16 (44.4%) in the high-dose and 20 (55.6%) in the regular-dose group were enrolled. The baseline characteristics were compatible between the two groups. The platelet counts were significantly higher at 1/3/6 months in the high-dose group (p = 0.028, 0.0063 and p = 0.040, respectively). The high-dose group had a significantly shorter time to platelet transfusion independence ([1 (0.5-6) months vs 2.5 (1-12) months, p = 0.040]). There was no significant difference in overall response and complete response rate between the two groups at 1/3/6/12 months (p > 0.05). Treatment-related morbidities were similar between the two groups (p > 0.05).

CONCLUSIONS

Adding a higher dose of rhTPO can further accelerate platelet recovery and platelet transfusion independence in patients with newly diagnosed NSAA.

Efficacy and safety of sovleplenib (HMPL-523) in adult patients with chronic primary immune thrombocytopenia in China (ESLIM-01): a randomised, double-blind, placebo-controlled, phase 3 study

BACKGROUND

Sovleplenib, a novel spleen tyrosine kinase (SYK) inhibitor, showed promising safety and activity in patients with primary immune thrombocytopenia in a phase 1b/2 trial. We aimed to evaluate the efficacy and safety of sovleplenib in patients with chronic primary immune thrombocytopenia.

METHODS

This randomised, double-blind, placebo-controlled, phase 3 trial (ESLIM-01) was done in 34 clinical centres in China. Eligible patients, aged 18-75 years, had chronic primary immune thrombocytopenia, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and received one or more previous treatments. Patients were randomly assigned (2:1) to receive oral sovleplenib or placebo, 300 mg once daily, for 24 weeks. Randomisation was stratified by baseline platelet counts, previous splenectomy, and concomitant treatment for anti-immune thrombocytopenia at baseline. The primary endpoint was durable response rate (proportion of patients with a platelet count of ≥50 × 109/L on at least four of six scheduled visits between weeks 14 and 24, not affected by rescue treatment) assessed by intention-to-treat. The trial is registered with ClinicalTrials.gov, NCT05029635, and the extension, open-label phase is ongoing.

FINDINGS

Between Sept 29, 2021, and Dec 31, 2022, 188 patients were randomly assigned to receive sovleplenib (n=126) or placebo (n=62). 124 (66%) were female, 64 (34%) were male, and all were of Asian ethnicity. Median previous lines of immune thrombocytopenia therapy were 4·0, and 134 (71%) of 188 patients had received previous thrombopoietin or thrombopoietin receptor agonist. The primary endpoint was met; durable response rate was 48% (61/126) with sovleplenib compared with zero with placebo (difference 48% [95% CI 40-57]; p<0·0001). The median time to response was 8 days with sovleplenib compared with 30 days with placebo. 125 (99%) of 126 patients in the sovleplenib group and 53 (85%) of 62 in the placebo group reported treatment-emergent adverse events (TEAEs), and most events were mild or moderate. Frequent TEAEs of grade 3 or higher for sovleplenib versus placebo were platelet count decreased (7% [9/126] vs 10% [6/62]), neutrophil count decreased (3% [4/126] vs 0% [0/62]), and hypertension (3% [4/126] vs 0% [0/62]). Incidences of serious TEAEs were 21% (26/126) in the sovleplenib group and 18% (11/62) in the placebo group. There were no deaths in the study.

INTERPRETATION

Sovleplenib showed a clinically meaningful sustained platelet response in patients with chronic primary immune thrombocytopenia, with a tolerable safety profile and improvement in quality of life. Sovleplenib could be a potential treatment option for patients with immune thrombocytopenia who received one or more previous therapy.

FUNDING

HUTCHMED and Science and Technology Commission of Shanghai Municipality.

Recombinant human thrombopoietin (rhTPO) of different dosing regimens for refractory/relapsed primary immune thrombocytopenia: a multicenter, randomized controlled trial and pharmacokinetics study

Recombinant human TPO (rhTPO) is effective for refractory/relapsed primary immune thrombocytopenia (ITP), but optimal dosing regimen remains elusive. In this multicenter, randomized, controlled trial, a total of 282 adult ITP patients (mean age 47.3 years; 82 men) with a platelet count ≤30 × 10⁹/L or >30 × 10⁹/L with active bleeding randomly received a once daily (QD) subcutaneous injection of 7500 U (n = 64) or 15000 U rhTPO for 14 injections, or 15000 U or 30000 U rhTPO once every other day (QOD) for 7 injections. The primary outcomes included change from baseline in platelet count and total response rate (TRR) on day 14. On day 14, the median increase of platelet count from baseline was the highest in the 15000-U QD group (167.5 × 10⁹/L, interquartile range [IQR] 23.0-295.0 × 10⁹/L), followed by the 30000-U QOD group (57.5 × 10⁹/L, IQR 9.0-190.0 × 10⁹/L) (ANCOVA P < .001; P = .266 with baseline count as a covariate). The TRR on day 14 was also the highest in the 15000-U QD group (63.2%), followed by the 30000-U QOD group (59.7%). The rate of grade 3 and above adverse events did not differ among the four groups. There were no new safety concerns. All 4 regimens are safe and well-tolerated. The 30000-U QOD regimen is practically indistinguishable in efficacy to the 15000-U QD regimen.

Efficacy and safety of high dose recombinant human thrombopoietin in the treatment of immune thrombocytopenia

The conventional dose of recombinant human thrombopoietin (rhTPO) in the treatment of immune thrombocytopenia (ITP) is 300 U/kg per day, but the clinical reaction rate is not satisfactory. Accordingly, we explored the efficacy and safety of increasing rhTPO dose in the treatment of ITP. A retrospective study was conducted to collect the clinical data of 105 ITP patients who were divided into two groups, a low-dose group (15 000 U/day) and a high-dose group (30 000 U/day) according to the dose of rhTPO. The total effective rate of the low-dose group and the high-dose group was 31/44 (70.45%) vs. 56/61 (91.80%) (P = .049), and the average time of using rhTPO in the high-dose group was shorter than that in the low-dose group (7 days vs. 10 days, P = .001). On the 7th and 14th day of treatment, the efficacy of the high-dose group was better than that of the low-dose group [45/61 (73.77%) vs. 17/44 (38.64%), P < .001; 55/60 (91.67%) vs. 30/44 (68.18%), P < .05)]. The incidence of treatment related adverse events in the low-dose group and the high-dose group was 6/44 (13.64%) vs. 6/61 (9.84%) (P > .05), which were mild and transient in nature. In our study, high-dose rhTPO had good efficacy and high safety in the treatment of ITP with the efficacy better than low-dose rhTPO especially at day 7.

Primary and secondary immune thrombocytopenia (ITP): Time for a rethink

There are not many publications that provide a holistic view of the management of primary and secondary ITP as a whole, reflecting the similarities and differences between the two. Given the lack of major clinical trials, we believe that comprehensive reviews are much needed to guide the diagnosis and treatment of ITP today. Therefore, our review addresses the contemporary diagnosis and treatment of ITP in adult patients. With respect to primary ITP we especially focus on establishing the management of ITP based on the different and successive lines of treatment. Life-threatening situations, "bridge therapy" to surgery or invasive procedures and refractory ITP are also comprehensively reviewed here. Secondary ITP is studied according to its pathogenesis by establishing three major differential groups: Immune Thrombocytopenia due to Central Defects, Immune Thrombocytopenia due to Blocked Differentiation and Immune Thrombocytopenia due to Defective Peripheral Immune Response. Here we provide an up-to-date snapshot of the current diagnosis and treatment of ITP, including a special interest in addressing rare causes of this disease in our daily clinical practice. The target population of this review is adult patients only and the target audience is medical professionals.

Application of recombinant human thrombopoietin in pregnant women with immune thrombocytopenia: a single-center experience of four patients and literature review

The management of pregnant women with immune thrombocytopenia who fail to respond to corticosteroids and intravenous immunoglobulin is an intractable clinical challenge because of the limited availability of evidence-based information. Recombinant human thrombopoietin (rhTPO) is recommended for refractory immune thrombocytopenia (ITP). To date, however, few studies have investigated rhTPO treatment during pregnancy. We retrospectively reviewed four cases who were diagnosed with ITP and treated with rhTPO during pregnancy in our center from January 2015 to June 2020. Of the four cases, two (50%) responded to rhTPO treatment. No adverse events were noted in the newborns. Our findings indicate that rhTPO treatment is safe for patients with refractory gestational ITP, and that subcutaneous injection is a convenient delivery method that does not lead to adverse events. Thus, rhTPO may be a viable alternative treatment option for patients with refractory gestational ITP who do not respond to first-line therapies.

Risk of thrombotic events in immune thrombocytopenia patients treated with thrombopoietic agents: a systematic review and meta-analysis

BACKGROUND

Immune thrombocytopenia (ITP), which is a well-known hemorrhagic disorder characterized by low platelet counts, has been shown to be associated with the risk of thrombosis. Thrombopoietic agents (TAs) are extensively used as second-line treatments for ITP, effectively reducing the risk of hemorrhage. However, thrombosis, a potential adverse effect of TAs, raises clinical challenges.

METHODS

The MEDLINE(PubMed), Embase, and the Cochrane Library databases were systematically searched for relevant studies, including both single-arm trials and randomized controlled trials (RCTs), without language restrictions.

RESULTS

A total of 17 RCTs comprising 2,105 patients and 29 single-arm trials comprising 3,227 patients were included. In the single-arm meta-analysis, the pooled rate of overall thrombotic events in ITP patients receiving TAs was 2.2% (95% CI 1.0% - 3.7%). In RCTs, a higher incidence of thrombosis (33/1425 vs. 4/680) and higher risk ratios (RR) of overall, arterial, and venous thrombotic events (1.73, 95% CI [0.88, 3.39], P = 0.113; RR 1.98, 95% CI [0.80, 4.92], P = 0.141; RR 1.06, 95% CI [0.46, 2.41], P = 0.895, respectively) were observed in the TAs group than in the control group, although the differences were not significant. Subgroup analysis demonstrated that hetrombopag was the only TA with no increased thrombotic risk (rate 0.3% 95% CI [0.0 - 1.5%]; RR 0.76, 95% CI [0.03, 18.41], P = 0.864) compared to eltrombopag, avatrombopag, romiplostim, and rhTPO. Subgroup analyses also revealed that ITP patients with advanced age (3.7% vs. 1.3%, P = 0.132) or with a thrombotic history (3.0% vs. 1.4%, P = 0.257), and patients who received TAs therapy for a long duration (4.7% vs. 0.1%, P < 0.001) had an increased risk of thrombosis.

CONCLUSION

Our findings suggest ITP patients treated with TAs have a nonsignificantly higher risk of overall, arterial, and venous thrombotic events. Furthermore, hetrombopag is the recommended TA to avoid thrombophilia. Patients receiving long-term TAs, as well as elderly ITP patients or those with a history of thrombosis, face an increased thrombotic risk. In general, clinicians should consider potential thrombotic risks, address underlying risk factors, and ensure ongoing monitoring and follow-up when treating ITP patients with TAs.

Recombinant human thrombopoietin promotes platelet recovery in DCAG-treated patients with intermediate-high-risk MDS/hypoproliferative AML

BACKGROUND

This study aimed to explore the effects of recombinant human thrombopoietin (rhTPO) on platelet recovery in decitabine, cytarabine, aclarubicin, and G-CSF (DCAG)-treated patients with intermediate-high-risk myelodysplastic syndrome/hypo proliferative acute myeloid leukemia.

METHODS

Recruited patients were at a ratio of 1:1 into 2 groups: the rhTPO group (DCAG + rhTPO) and control group (DCAG). The primary endpoint was the time for platelets to recover to ≥ 20 × 109/L. The secondary endpoints were the time for platelets to recover to ≥ 30 × 109/L and ≥ 50 × 109/L, overall survival (OS), and progression-free survival (PFS).

RESULTS

The time required for platelet recovery to ≥ 20 × 109/L, ≥30 × 109/L, and ≥ 50 × 109/L in the rhTPO group was significantly shorter (6.5 ± 2.2 vs 8.4 ± 3.1 days, 9.0 ± 2.7 vs 12.2 ± 3.9 days, 12.4 ± 4.7 vs 15.5 ± 9.3 days, respectively; all P < .05 vs controls). The amount of platelet transfusion in the rhTPO group was smaller (4.4 ± 3.1 vs 6.1 ± 4.0 U, P = .047 vs controls). The bleeding score was lower (P = .045 vs controls). The OS and PFS were significantly different (P = .009 and P = .004). The multivariable analysis showed that age, karyotype, and time for PLT recovery to ≥ 20 × 109/L were independently associated with OS. Adverse events were similar.

CONCLUSIONS

This study suggests that rhTPO leads to a faster platelet recovery after DCAG treatment, reduces the risk of bleeding, reduces the number of platelet transfusions, and prolongs the OS and PFS.

Efficacy and safety of treatments in newly diagnosed adult primary immune thrombocytopenia: A systematic review and network meta-analysis

BACKGROUND

Immune thrombocytopenia is an autoimmune disease characterised by decreased platelet count. In recent years, novel therapeutic regimens have been investigated in randomised controlled trials (RCTs). We aimed to compare the efficacy and safety of different treatments in newly diagnosed adult primary immune thrombocytopenia.

METHODS

We did a systematic review and network meta-analysis of RCTs involving treatments for newly diagnosed primary immune thrombocytopenia. PubMed, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched up to April 31, 2022. The primary outcomes were 6-month sustained response and early response. Secondary outcome was grade 3 or higher adverse events. This study is registered with PROSPERO (CRD42022296179).

FINDINGS

Eighteen RCTs (n = 1944) were included in this study. Pairwise meta-analysis showed that the percentage of patients achieving early response was higher in the dexamethasone-containing doublet group than in the dexamethasone group (79.7% vs 68.7%, odds ratio [OR] 1.82, 95% CI 1.10-3.02). The difference was more profound for sustained response (60.5% vs 37.4%, OR 2.57, 95% CI 1.95-3.40). Network meta-analysis showed that dexamethasone plus recombinant human thrombopoietin ranked first for early response, followed by dexamethasone plus oseltamivir or tacrolimus. Rituximab plus prednisolone achieved highest sustained response, followed by dexamethasone plus all-trans retinoic acid or rituximab. Rituximab plus dexamethasone showed 15.3% of grade 3 or higher adverse events, followed by prednis(ol)one (4.8%) and all-trans retinoic acid plus dexamethasone (4.7%).

INTERPRETATION

Our findings suggested that compared with monotherapy dexamethasone or prednis(ol)one, the combined regimens had better early and sustained responses. rhTPO plus dexamethasone ranked top in early response, while rituximab plus corticosteroids obtained the best sustained response, but with more adverse events. Adding oseltamivir, all-trans retinoic acid or tacrolimus to dexamethasone reached equally encouraging sustained response, without compromising safety profile. Although this network meta-analysis compared all the therapeutic regimens up to date, more head-to-head RCTs with larger sample size are warranted to make direct comparison among these strategies.

FUNDING

National Natural Science Foundation of China, Major Research Plan of National Natural Science Foundation of China, Shandong Provincial Natural Science Foundation and Young Taishan Scholar Foundation of Shandong Province.

How we treat primary immune thrombocytopenia in adults

Primary immune thrombocytopenia (ITP) is an immune-mediated bleeding disorder characterized by decreased platelet counts and an increased risk of bleeding. Multiple humoral and cellular immune abnormalities result in accelerated platelet destruction and suppressed platelet production in ITP. The diagnosis remains a clinical exclusion of other causes of thrombocytopenia. Treatment is not required except for patients with active bleeding, severe thrombocytopenia, or cases in need of invasive procedures. Corticosteroids, intravenous immunoglobulin, and anti-RhD immunoglobulin are the classical initial treatments for newly diagnosed ITP in adults, but these agents generally cannot induce a long-term response in most patients. Subsequent treatments for patients who fail the initial therapy include thrombopoietic agents, rituximab, fostamatinib, splenectomy, and several older immunosuppressive agents. Other potential therapeutic agents, such as inhibitors of Bruton's tyrosine kinase and neonatal Fc receptor, are currently under clinical evaluation. An optimized treatment strategy should aim at elevating the platelet counts to a safety level with minimal toxicity and improving patient health-related quality of life, and always needs to be tailored to the patients and disease phases. In this review, we address the concepts of adult ITP diagnosis and management and provide a comprehensive overview of current therapeutic strategies under general and specific situations.

A Network Meta-Analysis of Two Doses of Recombinant Human Thrombopoietin for Treating Sepsis-Related Thrombocytopenia

Previous studies suggest that sepsis remains a common critical illness with a global incidence of 31.5 million. The aim of this study was to evaluate the comparative therapeutic value of recombinant human thrombopoietin (rhTPO) in treating sepsis patients with thrombocytopenia. We conducted a comprehensive electronic search of PubMed, EMBASE, the Cochrane Library, and CNKI from its inception through December 31, 2021. Thirteen randomized controlled trials (RCTs) involving 963 patients were included. Network meta-analyses showed that rhTPO 300 U/kg/day and rhTPO 15000 U/day significantly increased the platelet (PLT) levels on the 7th day and decreased the requirement of transfusion of red blood cells (RBCs), plasma, and PLT compared with IVIG and NAT. SUCRA showed that rhTPO 300 U/kg/day ranked first in terms of 28-day mortality (85.5%) and transfusion, including RBC (88.7%), plasma (89.6%), and PLT (95.2%), while rhTPO 15000 U/day ranked first for the length of the intensive care unit (ICU) stay (95.9%) and PLT level at day 7 (91.6%). rhTPO 300 U/kg/day may be the optimal dose to reduce 28-day mortality and transfusion requirements. However, rhTPO 15000 U/day may be the optimal dose for shortening the ICU stay and increasing the PLT level on the 7th day. However, additional studies to further validate our findings are needed.

The Clinical Efficacy and Economic Benefits of Recombinant Human Thrombopoietin for the Treatment of Chemotherapy or Chemoradiotherapy-Induced Thrombocytopenia

Even though cytopenia caused by either chemotherapy or radiotherapy is a common complication in cancer patients, chemoradiotherapy remains an essential treatment for the majority of patients. The purpose of this study was to look into the clinical efficacy and cost-effectiveness of recombinant human thrombopoietin (rhTPO) in treating chemo- or chemoradiotherapy-induced grade II, III, and IV thrombocytopenia. From December 2019 to November 2020, 233 lung cancer patients admitted to our hospital with chemotherapy- or chemoradiotherapy-induced thrombocytopenia were enrolled and treated with rhTPO. The study's findings revealed a significant disparity in the use of concurrent chemoradiotherapy in patients with grade II, III, and IV thrombocytopenia. All costs, including rhTPO treatment costs, platelet costs, drug costs, and nondrug costs, tended to rise as the severity of thrombocytopenia increased. In the treatment of chemotherapy or radiotherapy-induced thrombocytopenia, rhTPO has shown good clinical efficacy. In the treatment of grade II thrombocytopenia, rhTPO has a favorable economic evaluation. As a result, early intervention and thrombocytopenia treatment should be provided, which warrants further clinical investigation.

Recombinant human thrombopoietin increases platelet count in severe thrombocytopenic patients with hepatitis B-related cirrhosis: Multicentre real-world observational study

Patients with hepatitis B-related cirrhosis complicated with thrombocytopenia have a higher risk of bleeding, which may lead to higher mortality. We aimed to explore the efficacy and safety of recombinant human thrombopoietin (rhTPO) in the treatment of hepatitis B-related cirrhosis complicated with severe thrombocytopenia. Patients with hepatitis B-related compensated liver cirrhosis complicated with severe thrombocytopenia were divided into four groups according to the treatment method for thrombocytopenia. Platelet counts, the appearance of bleeding symptoms and adverse events were evaluated during the observation period. Also during the observational period, the platelet counts in the prednisone group, rhTPO group and prednisone plus rhTPO group were higher than those in the no treatment group. Patients without splenomegaly reacted better to rhTPO. Fewer bleeding events of grade 2 or worse were observed in the three treatment groups compared to the no treatment group. The platelet counts at baseline and treatment with rhTPO and/or prednisone were factors associated with bleeding events of grade 2 or worse in multivariate analysis. There could be a potential advantage for the use of rhTPO plus prednisone based on higher platelet counts and fewer bleeding events. Treatment with rhTPO was more effective in patients without splenomegaly.

Refractory primary immune thrombocytopenia (ITP): current clinical challenges and therapeutic perspectives

Chronic primary immune thrombocytopenia (ITP) can today benefit from multiple therapeutic approaches with proven clinical efficacy, including rituximab, thrombopoietin receptor agonists (TPO-RA), and splenectomy. However, some ITP patients are unresponsive to multiple lines of therapy with prolonged and severe thrombocytopenia. The diagnosis of refractory ITP is mainly performed by exclusion of other disorders and is based on the clinician's expertise. However, it significantly increases the risk of drug-related toxicity and of bleedings, including life-threatening events. The management of refractory ITP remains a major clinical challenge. Here, we provide an overview of the currently available treatment options, and we discuss the emerging rationale of new therapeutic approaches and their strategic combination. Particularly, combination strategies may target multiple pathogenetic mechanisms and trigger additive or synergistic effects. A series of best practices arising both from published studies and from real-life clinical experience is also included, aiming to optimize the management of refractory ITP.

Recombinant Human Thrombopoietin Accelerates the Recovery of Platelet in Patients With Lower-Risk Myelodysplastic Syndrome: A Proof-of-Concept Study

Aim

The effect of recombinant human thrombopoietin (rhTPO) is largely unknown in lower-risk myelodysplastic syndrome (LR-MDS). This study aimed at investigating the safety and efficacy of rhTPO in patients with LR-MDS.

Methods

LR-MDS patients receiving stanozolol (2 mg, t.i.d.) and supportive care alone (non-rhTPO) or additional rhTPO were enrolled in this study prospectively. rhTPO was given at 15,000 U (q.d.) for 7 days/month for at least 3 months. Patients stopped rhTPO if the platelet count was higher than 50 × 10⁹/L or had no effects after 3 months of treatment. The overall response (OR), complete response (CR), platelet response, side effects, clone evolution, and clinical outcome were evaluated.

Result

Thirty-five patients were enrolled: 20 (57.1%) patients in the rhTPO group and 15 (42.9%) patients in the non-rhTPO group. The demographic and baseline characteristics were balanced between the two groups. Platelet response was higher at 1 and 2 months as compared with that in the non-rhTPO group (p = 0.006 and p = 0.001, respectively). Meanwhile, the rhTPO group had a shorter time to achieve a platelet transfusion-free state compared with the non-rhTPO group (p = 0.034). Hematologic response was higher at 1 and 2 months compared with that in the non-rhTPO group (p = 0.006 and p = 0.001, respectively). There was no significant difference in the overall response or complete response at 1, 2, 3, 6, and 12 months between the two groups. One patient in the rhTPO group evolved into higher-risk MDS at 9 months. No significant difference in disease progression, infection, gastrointestinal disorders, or drug-related liver/renal injuries was found between the two groups (p > 0.05).

Conclusion

Adding short-term rhTPO can accelerate the early platelet response and decrease platelet transfusion, with no obvious side effects.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT04324060?cond=NCT04324060&draw=2, identifier NCT04324060

A multicentre double-blind, double-dummy, randomised study of recombinant human thrombopoietin versus eltrombopag in the treatment of immune thrombocytopenia in Chinese adult patients

We performed a double-blind, double-dummy controlled study to compare the efficacy between recombinant human thrombopoietin (rhTPO) and eltrombopag in rapidly increasing the platelet counts in Chinese patients with immune thrombocytopenia (ITP). A total of 96 patients diagnosed with ITP for ≥6 months who had baseline platelet counts of <30 × 10⁹ /l were randomly assigned (1:1 ratio) to receive eltrombopag 25 mg/day or rhTPO 300 u/kg for 2 weeks. Compared with the eltrombopag group, a significantly higher proportion of patients in the rhTPO group achieved platelet counts of ≥50 × 10⁹ /l [75·00% (36/48) vs. 43·75% (21/48), P = 0·003] or complete response (64·58% vs. 25·00%) on day 15. Moreover, a higher proportion of patients in the rhTPO group either had platelet counts that rapidly increased to twice that of baseline and with platelet counts of ≥30 × 10⁹ /l, or reached ≥50 × 10⁹ /l at least once when analysed on day 9, 12, and 15. However, upon discontinuation of the treatment, the platelet counts reduced to the baseline within 1 week in the rhTPO group, but on the fourth week in the eltrombopag group. Adverse events were similar in patients given rhTPO and eltrombopag. To conclude, rhTPO is superior to eltrombopag at 25 mg/day in rapidly increasing platelet counts in patients with ITP (ClinicalTrials.gov Identifier: NCT03771378).

Immune Thrombocytopenia: Recent Advances in Pathogenesis and Treatments

Immune thrombocytopenia (ITP) is a rare autoimmune disease due to both a peripheral destruction of platelets and an inappropriate bone marrow production. Although the primary triggering factors of ITP remain unknown, a loss of immune tolerance-mostly represented by a regulatory T-cell defect-allows T follicular helper cells to stimulate autoreactive splenic B cells that differentiate into antiplatelet antibody-producing plasma cells. Glycoprotein IIb/IIIa is the main target of antiplatelet antibodies leading to platelet phagocytosis by splenic macrophages, through interactions with Fc gamma receptors (FcγRs) and complement receptors. This allows macrophages to activate autoreactive T cells by their antigen-presenting functions. Moreover, the activation of the classical complement pathway participates to platelet opsonization and also to their destruction by complement-dependent cytotoxicity. Platelet destruction is also mediated by a FcγR-independent pathway, involving platelet desialylation that favors their binding to the Ashwell-Morell receptor and their clearance in the liver. Cytotoxic T cells also contribute to ITP pathogenesis by mediating cytotoxicity against megakaryocytes and peripheral platelets. The deficient megakaryopoiesis resulting from both the humoral and the cytotoxic immune responses is sustained by inappropriate levels of thrombopoietin, the major growth factor of megakaryocytes. The better understanding of ITP pathogenesis has provided important therapeutic advances. B cell-targeting therapies and thrombopoietin-receptor agonists (TPO-RAs) have been used for years. New emerging therapeutic strategies that inhibit FcγR signaling, the neonatal Fc receptor or the classical complement pathway, will deeply modify the management of ITP in the near future.

Emerging Therapies in Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a rare autoimmune disorder caused by peripheral platelet destruction and inappropriate bone marrow production. The management of ITP is based on the utilization of steroids, intravenous immunoglobulins, rituximab, thrombopoietin receptor agonists (TPO-RAs), immunosuppressants and splenectomy. Recent advances in the understanding of its pathogenesis have opened new fields of therapeutic interventions. The phagocytosis of platelets by splenic macrophages could be inhibited by spleen tyrosine kinase (Syk) or Bruton tyrosine kinase (BTK) inhibitors. The clearance of antiplatelet antibodies could be accelerated by blocking the neonatal Fc receptor (FcRn), while new strategies targeting B cells and/or plasma cells could improve the reduction of pathogenic autoantibodies. The inhibition of the classical complement pathway that participates in platelet destruction also represents a new target. Platelet desialylation has emerged as a new mechanism of platelet destruction in ITP, and the inhibition of neuraminidase could dampen this phenomenon. T cells that support the autoimmune B cell response also represent an interesting target. Beyond the inhibition of the autoimmune response, new TPO-RAs that stimulate platelet production have been developed. The upcoming challenges will be the determination of predictive factors of response to treatments at a patient scale to optimize their management.

High-dose dexamethasone plus recombinant human thrombopoietin vs high-dose dexamethasone alone as frontline treatment for newly diagnosed adult primary immune thrombocytopenia: A prospective, multicenter, randomized trial

We conducted a prospective, multicenter, randomized, controlled clinical trial to compare the efficacy and safety of high-dose dexamethasone (HD-DXM) plus recombinant human thrombopoietin (rhTPO), vs HD-DXM alone in newly diagnosed adult immune thrombocytopenia (ITP) patients. Enrolled patients were randomly assigned to receive DXM plus rhTPO or DXM monotherapy. Another 4-day course of DXM was repeated if response was not achieved by day 10 in both arms. One hundred patients in the HD-DXM plus rhTPO arm and 96 patients in the HD-DXM monotherapy arm were included in the full analysis set. So, HD-DXM plus rhTPO resulted in a higher incidence of initial response (89.0% vs 66.7%, P < .001) and complete response (CR, 75.0% vs 42.7%, P < .001) compared with HD-DXM monotherapy. Response rate at 6 months was also higher in the HD-DXM plus rhTPO arm than that in the HD-DXM monotherapy arm (51.0% vs 36.5%, P = .02; sustained CR: 46.0% vs 32.3%, P = .043). Throughout the follow-up period, the overall duration of response was greater in the HD-DXM plus rhTPO arm compared to the HD-DXM monotherapy arm (P = .04), as estimated by the Kaplan-Meier analysis. The study drugs were generally well tolerated. In conclusion, the combination of HD-DXM with rhTPO significantly improved the initial response and yielded favorable SR in newly diagnosed ITP patients, thus could be further validated as a frontline treatment for ITP. This study is registered as clinicaltrials.gov identifier: NCT01734044.

American Society of Hematology 2019 guidelines for immune thrombocytopenia

BACKGROUND

Despite an increase in the number of therapies available to treat patients with immune thrombocytopenia (ITP), there are minimal data from randomized trials to assist physicians with the management of patients.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in their decisions about the management of ITP.

METHODS

In 2015, ASH formed a multidisciplinary guideline panel that included 8 adult clinical experts, 5 pediatric clinical experts, 2 methodologists with expertise in ITP, and 2 patient representatives. The panel was balanced to minimize potential bias from conflicts of interest. The panel reviewed the ASH 2011 guideline recommendations and prioritized questions. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including evidence-to-decision frameworks, to appraise evidence (up to May 2017) and formulate recommendations.

RESULTS

The panel agreed on 21 recommendations covering management of ITP in adults and children with newly diagnosed, persistent, and chronic disease refractory to first-line therapy who have non-life-threatening bleeding. Management approaches included: observation, corticosteroids, IV immunoglobulin, anti-D immunoglobulin, rituximab, splenectomy, and thrombopoietin receptor agonists.

CONCLUSIONS

There was a lack of evidence to support strong recommendations for various management approaches. In general, strategies that avoided medication side effects were favored. A large focus was placed on shared decision-making, especially with regard to second-line therapy. Future research should apply standard corticosteroid-dosing regimens, report patient-reported outcomes, and include cost-analysis evaluations.

[Immune thrombocytopenia: From pathogenesis to treatment]

Immune thrombocytopenia (ITP) is a rare autoimmune disease due to an immune peripheral destruction of platelets and an inappropriate platelet production. The pathogenesis of ITP is now better understood: it involves a humoral immune response which dependents on the stimulation of B cells by specific T cells called T follicular helper cells, leading to their differentiation into plasma cells that produce antiplatelet antibodies thus promoting the phagocytosis of platelets mainly by splenic macrophages. The deciphering of ITP pathogenesis has led to a better understanding of the inefficiency of treatments such as rituximab, although it has not provided yet the determination of biological predictive factor of response to treatments. Moreover, new therapeutic perspectives have been opened in the last few years with the development of molecules targeting Fcγ receptor signalling such as Syk inhibitor, or molecules increasing the clearance of pathogenic autoantibodies such as inhibitors of the neonatal Fc receptor (FcRn).

Efficacy and Safety of Recombinant Human Thrombopoietin on Sepsis Patients With Thrombocytopenia: A Systematic Review and Meta-Analysis

Background

The efficacy and safety of the administration of recombinant human thrombopoietin (rhTPO) in sepsis patients with thrombocytopenia were still inconclusive.

Objectives

To investigate whether rhTPO is a benefit for sepsis patients with thrombocytopenia.

Methods

PubMed, Cochrane library, Embase, China National Knowledge Infrastructure, and Wanfang Database were electronically searched to the randomized controlled trials (RCTs) from inception to March 4, 2020. The primary outcome was the level of platelet (PLT) on the 7^th day of treatment, and secondary outcomes were 28-d mortality, the level of coagulation indicators, hepatic and renal function indicators, blood transfusion, and length of intensive care unit (ICU) stay.

Results

Ten RCTs involving 681 patients were included. For compared with conventional antibiotic therapy, rhTPO could significantly increase platelet counts (PCs) [standardized mean difference (SMD), 2.61; 95% confidence interval (CI), 1.28-3.94; P < 0.001], decreased 28-d mortality [relative risk (RR), 0.66; 95%CI, 0.46-0.97; P=0.03], transfusion volume of blood products and length of ICU stay. Additionally, for compared with conventional antibiotic therapy combined with intravenous immunoglobulin, the pooled results shown that rhTPO also associated with an improvement of PCs on 7^th of treatment (SMD, 0.86; 95%CI, 0.54-1.17; P < 0.001), and a reduced transfusion volume of blood products. However, there were no differences in 28-d mortality and the length of ICU stay.

Conclusions

Current evidence shown that rhTPO could increase PCs on 7^th day of treatment and reduce the transfusion volume of blood products in sepsis-related thrombocytopenia during hospitalization. The conclusions are needed to be verified indeed by more multicenter RCTs due to the limitation of the included studies.

Recombinant human thrombopoietin in critically ill patients with sepsis-associated thrombocytopenia: A clinical study

BACKGROUND

Sepsis causes varying degrees of thrombocytopenia that are closely related to the likelihood of patient mortality. This study analysed the effect of recombinant human thrombopoietin (rhTPO) on the platelet count in critically ill patients with sepsis-associated thrombocytopenia and provided a reference for its treatment.

MATERIAL/METHODS

The study was a retrospective analysis of the clinical data of patients. Patients were divided into an rhTPO group and control group according to rhTPO use during treatment. Demographical and clinical data (age, sex, history of hypertension, diabetes, platelet counts, mortality rate, etc.) of the patients were collected and analysed using statistical software; p < 0.05 was considered statistically significant.

RESULTS

Of 213 patients, 84 constituted the rhTPO group and 129 constituted the control group. The increase in platelet counts was significantly higher in the rhTPO group than in the control group on the third day (43.01 ± 18.23 × 10⁹/L vs. 36.31 ± 14.17 × 10⁹/L, p = 0.003), fifth day (71.51 ± 39.59 × 10⁹/L vs. 42.95 ± 20.48 × 10⁹/L, p < 0.001) and seventh day (115.36 ± 69.41 × 10⁹/L vs. 62.54 ± 42.70 × 10⁹/L, p < 0.001). Further statistical analysis of the data of patients with platelet counts ≤30 × 10⁹/L and >30 × 10⁹/L and APACHE II scores >15 and ≤15 at the time of diagnosis showed that the increase in platelet counts in the rhTPO group was greater. There was no significant between-group difference in volume of platelet transfusions (rhTPO group 15.42 ± 17.20 vs. control group 10.93 ± 17.48, p = 0.068). The cost of ICU treatment in patients with rhTPO was higher (RMB 126,936.21 ± 86,548.27 vs. 101,685.28 ± 77,291.75, p = 0.027); however, the ICU stay time was shorter (9.20 ± 5.38 vs. 10.88 ± 6.82, p = 0.047). There was no significant difference in 28-day mortality (rhTPO group: 25.0% vs. control group: 34.1%, p = 0.158) between the two groups.

CONCLUSION

For patients with severe thrombocytopenia or severe sepsis, rhTPO was efficacious in increasing their platelet counts, resulting in a shorter ICU stay time.

Report of a 'consensus' on the lines of therapy for primary immune thrombocytopenia in adults, promoted by the Italian Gruppo di Studio delle Piastrine

Despite the publication in 2009 of a paper on 'terms and definitions of immune thrombocytopenia' (ITP), some unresolved issues remain and are reflected by the disagreement in the treatment suggested for primary ITP in adults. Considering that these disagreements could be ascribed to non-shared goals, we generated a 'consensus' on some terms, definitions, and assertions useful for classifying the different lines of treatment for primary ITP in adults according to their indications and goals. Agreement on the appropriateness of the single assertions was obtained by consensus for the following indicators: 1. classification of four 'lines of therapy'; 2. acceptance of the expression 'sequences of disease' for the indications of the respective four lines of treatment; 3_I . practicability of splenectomy; 3_Ib . acceptance, with only some exceptions, of a 'timing for elective splenectomy of 12 months'; and 4_a-d . 'goals of the four lines of therapy.' On the basis of the consensus, a classification of four lines of treatment for primary ITP in adults was produced. In our opinion, this classification, whose validity is not influenced by the recently published new guidelines of the American Society of Hematology (ASH) and reviews, could reduce the disagreement that still exists regarding the treatment of the disease.

Identifying and treating refractory ITP: difficulty in diagnosis and role of combination treatment

Immune thrombocytopenia (ITP) is the most common acquired thrombocytopenia after chemotherapy-induced thrombocytopenia. Existing guidelines describe the management and treatment of most patients who, overall, do well, even if they present with chronic disease, and they are usually not at a high risk for bleeding; however, a small percentage of patients is refractory and difficult to manage. Patients classified as refractory have a diagnosis that is not really ITP or have disease that is difficult to manage. ITP is a diagnosis of exclusion; no specific tests exist to confirm the diagnosis. Response to treatment is the only affirmative confirmation of diagnosis. However, refractory patients do not respond to front-line or other treatments; thus, no confirmation of diagnosis exists. The first section of this review carefully evaluates the diagnostic considerations in patients with refractory ITP. The second section describes combination treatment for refractory cases of ITP. The reported combinations are divided into the era before thrombopoietin (TPO) and rituximab and the current era. Current therapy appears to have increased effectiveness. However, the definition of refractory, if it includes insufficient response to TPO agents, describes a group with more severe and difficult-to-treat disease. The biology of refractory ITP is largely unexplored and includes oligoclonality, lymphocyte pumps, and other possibilities. Newer treatments, especially rapamycin, fostamatinib, FcRn, and BTK inhibitors, may be useful components of future therapy given their mechanisms of action; however, TPO agents, notwithstanding failure as monotherapy, appear to be critical components. In summary, refractory ITP is a complicated entity in which a precise specific diagnosis is as important as the development of effective combination treatments.

Management of immune thrombocytopenia in women: current standards and special considerations

Introduction: Immune thrombocytopenia (ITP) is an acquired autoimmune disorder, with an incidence rate of 20-40/million adults/year and an estimated prevalence in women of childbearing age of 24.5/million.Areas covered: Authors discuss management of ITP in pregnancy, treatment-related toxicity, delivery, neonatal thrombocytopenia and breastfeeding, and other women's specific issues. The search of papers published between January 1990 and December 2019 was done on PubMed using combinations of the keywords below. The distinction between ITP and other thrombocytopenias in pregnancy is of paramount importance. The current belief (at variance with the past) that ITP is a relatively benign disease pregnancy is emphasized.Expert opinion: The lack of randomized, prospective, controlled studies hampers evidence-based statements. Remarkably, ITP diagnosis is still one of exclusion, there are no clinical or laboratory criteria for prognosis and we still need more solid data on the risks related to neonatal thrombocytopenia. Corticosteroids and IVIG remain the mainstay of treatment, since rituximab, thrombopoietin-receptor agonists, fostamatinib may be toxic in pregnancy. Safety and efficacy of recombinant-human-thrombopoietin, available in China, require confirmation studies. Quality of life and women-related toxicity of treatments in young girls, adults, and elders are still an orphan area of investigation.

Romiplostim for the Treatment of Immune Thrombocytopenia: Spotlight on Patient Acceptability and Ease of Use

Immune thrombocytopenia (ITP) is an immune-mediated disorder resulting in platelet destruction and subsequent thrombocytopenia. Bleeding symptoms range from mild cutaneous bleeding to life-threatening hemorrhage. Romiplostim, a peptide-antibody fusion product, is a thrombopoietin receptor agonist (TPO-RA) indicated for use in patients with ITP. Romiplostim is US Food and Drug Administration (FDA) approved in children ≥1 year of age with ITP of >6 months' duration who have had an inadequate response to first-line therapies or splenectomy. FDA approval in adults with chronic ITP was expanded in October 2019 to include adults with newly diagnosed (<3 months' duration) and persistent (3-12 months' duration) ITP who demonstrated an inadequate response to first-line therapies, including corticosteroids and immunoglobulins, or splenectomy. The newly published 2019 American Society of Hematology ITP Guidelines place TPO-RAs, including romiplostim, as second-line therapies in both children and adults. Here, we review the use of romiplostim as second-line therapy with a spotlight on health-related quality of life, ease of use, and patient preference.

Updated international consensus report on the investigation and management of primary immune thrombocytopenia

Over the last decade, there have been numerous developments and changes in treatment practices for the management of patients with immune thrombocytopenia (ITP). This article is an update of the International Consensus Report published in 2010. A critical review was performed to identify all relevant articles published between 2009 and 2018. An expert panel screened, reviewed, and graded the studies and formulated the updated consensus recommendations based on the new data. The final document provides consensus recommendations on the diagnosis and management of ITP in adults, during pregnancy, and in children, as well as quality-of-life considerations.

The effect of recombinant human thrombopoietin (rhTPO) on sepsis patients with acute severe thrombocytopenia: a study protocol for a multicentre randomised controlled trial (RESCUE trial)

BACKGROUND

Sepsis is still a common critical disease with high morbidity and mortality in intensive care unit. Despite published guidelines for sepsis, development of antibiotic therapy and advanced organ support technologies, the mortality of sepsis patients is still 25% or more. It is necessary to distinguish the subtypes of sepsis, and the targeted therapy for the patients need to be explored. Platelets have various biological functions in hemostasis and thrombosis, host defense, inflammatory/immune responses and tissue repair/regeneration. Moreover, severe thrombocytopenia or sustained thrombocytopenia was closely associated with multiply organ dysfunction and higher mortality in sepsis patients. The clinical therapies for thrombocytopenia are platelet transfusion and platelet-elevating drugs. However, platelet transfusion has many defects in clinical practice in sepsis patients, and the impact of platelet-elevating drugs for sepsis patients is still unclear. RESCUE trial is aim to explore the effect of a platelet-elevating drug, recombinant human thrombopoietin (rhTPO), as an effective rescue therapy on sepsis patients with acute severe thrombocytopenia.

METHODS

It is a randomized, open-label, multi-center, controlled trial in 5 tertiary academic hospitals including medical, surgical or general ICUs. In this study, a total of 200 sepsis patients with severe thrombocytopenia will be randomly assigned in a 1:1 ratio to the control and rhTPO group. The patients will be followed up to 28 days after randomization. All patients in two groups receive the same treatment based on the guideline of Surviving Sepsis Campaign. Primary outcome is 28-day mortality. Secondary outcomes are the changes of PCs, blood transfusion, biomarkers of infection and organ function, days free from advanced organ support, drug-related adverse events, the length of ICU and hospital stay.

DISCUSSION

RESCUE trial is the first randomized controlled trial to explore the impact of rhTPO for severe thrombocytopenia in sepsis patients diagnosed by sepsis-3.0 standard. Furthermore, RESCUE trial results will be of significant clinical value on the targeted therapy and add clinical evidence that rhTPO is an effective rescue therapy for these sepsis patients.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT02707497. Registered Date: March 3rd, 2016. Protocol Version 3. Protocol Date: January 25th, 2019.

Treatment efficacy for adult persistent immune thrombocytopenia: a systematic review and network meta-analysis

Persistent immune thrombocytopenia (ITP) patients require second-line treatments, for which information on clinical outcomes are lacking. A systematic review and network meta-analysis (NMA) were conducted. Only randomised controlled trials (RCT) of second-line drugs in adult persistent ITP patients with platelet response, platelet count, any bleeding or serious adverse events (SAE) outcome were eligible. Twelve RCTs (n = 1313) were included in NMA. For platelet response outcome, eltrombopag and romiplostin were the best relative to placebo; the former had a non-significant advantage [risk ratio (RR) = 1·10 (95% confidence interval: 0·46, 2·67)]. Both treatments were superior to rituximab and recombinant human thrombopoietin (rhTPO)+rituximab, with corresponding RRs of 4·56 (1·89, 10·96) and 4·18 (1·21, 14·49) for eltrombopag; 4·13 (1·56, 10·94) and 3·79 (1·02, 14·09) for romiplostim. For platelet count, romiplostim ranked highest, followed by eltrombopag, rhTPO+rituximab, and rituximab. For bleeding, rituximab had lowest risk, followed by eltrombopag and romiplostim. For SAEs, rhTPO+rituximab had highest risk, followed by rituximab, eltrombopag and romiplostim. From clustered ranking, romiplostim had the best balance between short-term efficacy and SAEs, followed by eltrombopag. In conclusion, romiplostim and eltrombopag may yield high efficacy and safety. Rituximab may not be beneficial due to lower efficacy and higher complications compared with the thrombopoietin receptor agonists. RCTs with long-term clinical outcomes are required.

Therapeutic options for adult patients with previously treated immune thrombocytopenia - a systematic review and network meta-analysis

OBJECTIVES

The great majority of adult patients with immune thrombocytopenia (ITP) who fail to respond to first-line medication or who relapse following response require additional treatment. Although broad guidelines currently exist for second-line and subsequent therapies, none to date have been prescriptive. The purpose of this systematic review and network meta-analysis was to establish a clinically relevant ranking of the efficacy and safety of medications for adults (≥18 years old) with previously treated ITP.

METHODS

Relevant publications from Medline, Embase, and the Cochrane database were searched from their inceptions through July 31, 2018. The primary outcome was the overall response (OR, defined as a platelet count ≥50 × 10⁹/L at the end of treatment without rescue therapy), while the secondary endpoints included early response (ER; i.e. a platelet count ≥50 × 10⁹/L at week 2 after initiation of treatment) and therapy-related severe adverse events (AEs).

RESULTS

Thirteen randomized controlled trials (1,202 patients) were included in this study. According to pooled results, romiplostim appears to be the most suitable treatment in terms of OR, followed by avatrombopag, eltrombopag, fostamatinib, and rituximab. Avatrombopag produced more satisfactory outcomes than romiplostim, eltrombopag, and rituximab in terms of ER; severe AEs profiles were similar across all treatment arms.

CONCLUSION

Romiplostim appears to be the best option for patients who fail to respond to prior treatment or relapse thereafter, while avatrombopag and eltrombopag are reasonable alternatives. Rituximab monotherapy is not recommended, as it produces the lowest OR and ER rates.

Eltrombopag for use in children with immune thrombocytopenia

Eltrombopag is currently the only US Food and Drug Administration-approved thrombopoietin receptor agonist for the treatment of chronic immune thrombocytopenia (ITP) in children. This oral, once-per-day therapy has shown favorable efficacy and adverse effect profiles in children. Two multicenter, double-blind, placebo controlled clinical trials (PETIT [Efficacy and Safety Study of Eltrombopag in Pediatric Patients With Thrombocytopenia From Chronic Idiopathic Thrombocytopenic Purpura (ITP)] and PETIT2 [Study of a New Medication for Childhood Chronic Immune Thrombocytopenia (ITP), a Blood Disorder of Low Platelet Counts That Can Lead to Bruising Easily, Bleeding Gums, and/or Bleeding Inside the Body]) demonstrated efficacy in raising platelet counts, reducing bleeding, and reducing the need for concomitant ITP therapies with relatively few adverse effects. The most commonly reported drug-related adverse effects include headache, nausea, and hepatobiliary laboratory abnormalities. Long-term safety data in children are limited, and studies in adults have not revealed a clinically significant increased incidence of thrombosis, marrow fibrosis, or cataract formation. Eltrombopag has also been approved for treating refractory severe aplastic anemia (AA) and has potential for expanded use in ITP and severe AA as well as in other conditions associated with thrombocytopenia.

Systematic literature review of treatments used for adult immune thrombocytopenia in the second-line setting

Immune thrombocytopenia (ITP) is a rare platelet disorder that is often persistent or chronic in adults. Patient management is dependent upon physician judgment and patient preference, given both the rarity of the condition and a paucity of high-quality clinical trial evidence to inform practice guidelines. A systematic literature review was conducted to provide an up-to-date summary of studies evaluating the safety and efficacy/effectiveness of therapies used to treat adults with primary ITP in the second-line setting. Using comprehensive search strings, several medical research databases were queried. Final abstraction was performed on 186 articles. Most (75%) studies were observational in nature; nearly half were conducted in Europe. Splenectomy was the most commonly studied (n = 83, 47%), followed by rituximab (n = 49, 26%) and the thrombopoietin-receptor agonists (TPO-RAs) romiplostim (n = 34, 18%) and eltrombopag (n = 24, 13%). Twelve prospective, randomized controlled trials (RCTs) with a placebo or standard-of-care arm evaluating the safety and efficacy of either rituximab or a TPO-RA were identified and described in detail. These trials provide important information on the safety and efficacy of these treatments, and in the absence of head-to-head data, offer insights on how these therapies compare with one another in treating adult ITP in the second-line setting. This review confirms that for most second-line ITP treatment options, there remains a lack of rigorous evidence derived from RCTs, and for many treatments, there is limited evidence of any kind. The need for additional research to guide treatment choices in this setting and greater use of standardized ITP terminology are highlighted.

Effect of recombinant human thrombopoietin on immune thrombocytopenia in pregnancy in a murine model

Primary immune thrombocytopenia (ITP) is a serious medical disorder that has the potential for maternal and fetal mortality. Corticosteroids, intravenous immunoglobulin, or both are the first-line treatments for ITP in pregnancy, but choices are limited if patients fail to respond. Recombinant human thrombopoietin (rhTPO) has been proved effective and safe in management of chronic ITP. However, the efficacy and safety of rhTPO for pregnant ITP patients still need to be explored. Here we developed an ideal murine model that simulated human ITP in pregnancy and evaluated the efficacy and safety of rhTPO in management of ITP in pregnancy. Model mice were subcutaneously administered with 0, 150, 1,500 and 15,000 U/kg rhTPO for 14 days. Significant higher platelet counts were noted in rhTPO-treated groups on Day 7, 10 and 14. On Day 20, half the maternal mice were sacrificed. Frequencies of Tregs in CD4⁺ T cells in rhTPO-treated groups were statistically higher than control. Significant higher plasma levels of TGF-β1 were observed in rhTPO-treated groups than control. There was no significant abnormality in gross or visceral examination of fetuses. The remaining half maternal mice and their pups were observed for at least three weeks to assess vital signs. No abnormal signs were noted. Furthermore, we investigated the underlying mechanisms. Results showed that Tregs were negative for c-Mpl and rhTPO had no direct effect on Tregs. Additionally, the Treg frequency in splenic CD4⁺ T cells in LY2109761-treated model mice was statistically lower than control. Thus, rhTPO may be a safe and effective option for treatment of pregnant ITP patients.

Comparison of treatments for persistent/chronic immune thrombocytopenia: a systematic review and network meta-analysis

Recent studies have indicated that medical options without splenectomy, such as rituximab (RTX) or thrombopoietin receptor agonists (TPO-RAs), can be effective to treat persistent or chronic primary immune thrombocytopenia (ITP). However, it remains to be determined which of these strategies should be the first choice after the first-line treatment for newly diagnosed ITP. We performed a systematic review and network meta-analysis to establish a clinically meaningful hierarchy of the efficacy and safety of medical treatments for persistent or chronic ITP in adults. Randomized controlled trials (RCTs) evaluating medical treatments were included. Reviewers independently extracted data and assessed the risk of bias. The main outcome was the overall response (platelet≥ 50 × 10⁹/L); incidence of bleeding episodes, necessity of rescue treatments, and therapy-related adverse events including thrombosis were the secondary endpoints. A total of 12 randomized controlled trials (N= 1306) were included in this study. Our main finding was an improved overall response in TPO-RA arms (both Eltrombopag and Romiplostim) compared with that of RTX or placebo. There were no significant differences between Eltrombopag and Romiplostim. Moreover, clinically significant bleeding episodes were decreased in TPO-RA arm compared with placebo. Therapy-related adverse events showed similar profiles, and were tolerable in all treatment arms. In conclusion, TPO-RAs can be first choices for the treatment of persistent and chronic ITP, rather than RTX, as alternatives to splenectomy. Future head-to-head trials including TPO-RAs vs. RTX or Eltrombopag vs. Romiplostim are necessary to validate our study findings and determine the most suitable therapy for persistent/chronic ITP.

Chinese guidelines for treatment of adult primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is a bleeding disorder commonly encountered in clinical practice. The International Working Group (IWG) on ITP has published several landmark papers on terminology, definitions, outcome criteria, bleeding assessment, diagnosis, and management of ITP. The Chinese consensus reports for diagnosis and management of adult ITP have been updated to the 4th edition. Based on current consensus positions and new emerging clinical evidence, the thrombosis and hemostasis group of the Chinese Society of Hematology issued Chinese guidelines for management of adult ITP, which aim to provide evidence-based recommendations for clinical decision making.

A novel recombinant human thrombopoietin therapy for the management of immune thrombocytopenia in pregnancy

The aim of this study was to determine the safety and efficacy of recombinant human thrombopoietin (rhTPO) for the management of immune thrombocytopenia (ITP) during pregnancy. Pregnant patients with ITP were enrolled in the study if they had a platelet count less than 30 × 10⁹/L, were experiencing bleeding manifestations, had failed to respond to corticosteroids and/or intravenous immunoglobulin (IVIG), and had developed refractoriness to platelet transfusion. Thirty-one patients received rhTPO at an initial dose of 300 U/kg once daily for 14 days. Twenty-three patients responded (74.2%), including 10 complete responders (>100 × 10⁹/L) and 13 responders (30-100 × 10⁹/L). It appears that rhTPO ameliorated the bleeding symptoms remarkably, even in the nonresponders. rhTPO was well tolerated. Dizziness, fatigue, and pain at an injection site were reported in 1 patient each. No congenital disease or developmental delays were observed in the infants in a median follow-up of 53 (range, 39-68) weeks. In conclusion, rhTPO is a potentially safe and effective treatment choice for patients with ITP during pregnancy. Our work has paved the way for further study on the clinical application of rhTPO and other thrombopoietic agents for the management of ITP during pregnancy. This study is registered at www.clinicaltrials.gov as NCT02391272.

[A prospective study of the efficacy and safety of maintenance therapy with recombinant human thrombopoietin in patients with primary immune thrombocytopenia: a multicenter study]

Objective: To evaluate the efficacy and safety of maintenance therapy with reduced dose of rhTPO in the patients with primary immune thrombocytopenia (ITP) who attained stable platelet (PLT) counts after daily administration of rhTPO. Methods: Treatment was started with a daily administration of rhTPO (300 U/kg) for 2 consecutive weeks. Patients who attained stable PLT≥50×10(9)/L were enrolled to maintenance therapy starting with every other day administration of rhTPO, then adjusted dose interval to maintain platelet count (30-100) ×10(9)/L. Results: A total of 91 eligible patients were enrolled. Fourteen patients discontinued the study due to noncompliance (12/14) and investigator decision (2/14) . Among 77 patients who completed the study, 38 patients with the administration of rhTPO at every other day or less could maintain PLT≥30×10(9)/L for 12 weeks. The percentage of patients with a platelet response (PLT≥30×10(9)/L) at 4(th) week, 8(th) week and 12(th) week of maintain therapy was 92.6% (63/68) , 82.7% (43/52) and 85.0% (34/40) , respectively. Median platelet counts remained in the range of (70-124) ×10(9)/L. The overall incidence of rhTPO-related adverse events was 7.7%. All the adverse events were generally mild. Conclusion: Extending the dose interval of rhTPO is feasible to maintain stable platelet count in the patients with ITP, but the optimal dose interval is uncertain and might vary with individuals.

Pathogenesis-oriented approaches for the management of corticosteroid-resistant or relapsedprimary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is a complex autoimmune disorder in which the patient’s immune system reacts with platelet autoantigens resulting in immune-mediated platelet destruction and/or suppression of platelet production. Corticosteroids can induce sustained remission rates in 50% to 75% of patients with active ITP. For these patients who are unresponsive to glucocorticoids, or relapsed after an initial response, multiple second-line treatment modalities can be chosen. However, how to make an optimal therapeutic strategy for a specific patient still remains a major challenge. As the pathogenetic heterogeneity of the ITP is increasingly identified, pathogenesis-oriented approach might offer an opportunity to improve the outcome of corticosteroid-resistant or relapsed ITP.