Romiplostim in the management of the thrombocytopenic surgical patient

Thrombopoietin Receptor Agonists in Post-Hematopoietic Cell Transplantation Complicated by Prolonged Thrombocytopenia: A Comprehensive Review

Hematopoietic cell transplantation (HCT) is a well-established procedure that has become a therapeutic mainstay for various hematological conditions. Prolonged thrombocytopenia following HCT is associated with a significant risk of morbidity and mortality, yet no universally recognized treatment protocol exists for such a complication. First-generation thrombopoietin receptor (TpoR) agonists as well as second-generation agents are known for their role in enhancing platelet production, and their use is expanding across various thrombocytopenic conditions. Therefore, we conducted this comprehensive review of the literature to provide an updated evaluation of the use of TpoR agonists and explore their efficacy and safety in the treatment of extended post-HCT thrombocytopenia. The literature search was conducted using PubMed database from 1996 through December 2023, using a predefined strategy with medical subject headings terms. We identified 64 reports on the utility of TpoR agonists, five of them were randomized controlled trials and the rest were retrospective observational studies and case series, with a total number of 1730 patients. Second-generation TpoR agonists appear more convenient than subcutaneous recombinant human thrombopoietin (rhTpo) as they can be orally administered and exhibit similar efficacy in platelet recovery, as indicated by recent trial results. Among these agents, avatrombopag, unlike eltrombopag, does not require any dietary restrictions, which could be more favorable for patients. However, eltrombopag remains the most extensively studied agent. TpoR agonists had promising effects in the treatment of post-HCT thrombocytopenia with a good safety profile so far, highlighting the potential benefit of their use.

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.

Dentoalveolar Procedures in Immune Thrombocytopenia; Systematic Review and an Institutional Guideline

Background  Dentoalveolar procedures in immune thrombocytopenia (ITP) pose a risk of bleeding due to thrombocytopenia and infection due to immunosuppressive treatments. We aimed to systematically review the safety and management of dentoalveolar procedures in ITP patients to create practical recommendations.

Methods  PubMed, Embase, Cochrane, and Cinahl were searched for original studies on dentoalveolar procedures in primary ITP patients. We recorded bleeding- and infection-related outcomes and therapeutic strategies. Clinically relevant bleeding was defined as needing medical attention.

Results  Seventeen articles were included, of which 12 case reports/series. Overall, the quality of the available evidence was poor. Outcomes and administered therapies (including hemostatic therapies and prophylactic antibiotics) were not systematically reported. At least 73 dentoalveolar procedures in 49 ITP patients were described. The range of the preoperative platelet count was 2 to 412 × 10 ⁹ /L. Two clinically relevant bleedings (2%) were reported in the same patient of which one was life-threatening. Strategies used to minimize the risk of bleeding were heterogeneous and included therapies to increase platelet count, antifibrinolytics, local measures, and minimally invasive techniques. Reports on the occurrence of bleedings due to anesthetics or infection were lacking.

Conclusion  Based on alarmingly limited data, clinically relevant bleedings and infections after dentoalveolar procedures in ITP patients seem rare. Awaiting prospective and controlled studies to further evaluate these risks and the efficacy of therapeutic interventions, we provided our institutional guideline to guide the management of dentoalveolar procedures in ITP patients.

Perioperative thrombocytopenia

PURPOSE OF REVIEW

In this review, we discuss recent developments and trends in the perioperative management of thrombocytopenia.

RECENT FINDINGS

Large contemporary data base studies show that preoperative thrombocytopenia is present in about 8% of asymptomatic patients, and is associated with increased risks for bleeding and 30-day mortality. Traditionally specific threshold platelet counts were recommended for specific procedures. However, the risk of bleeding may not correlate well with platelet counts and varies with platelet function depending on the underlying etiology. Evidence to support prophylactic platelet transfusion is limited and refractoriness to platelet transfusion is common. A number of options exist to optimize platelet counts prior to procedures, which include steroids, intravenous immunoglobulin, thrombopoietin receptor agonists, and monoclonal antibodies. In addition, intraoperative alternatives and adjuncts to transfusion should be considered. It appears reasonable to use prophylactic desmopressin and antifibrinolytic agents, whereas activated recombinant factor VII could be considered in severe bleeding. Other options include enhancing thrombin generation with prothrombin complex concentrate or increasing fibrinogen levels with fibrinogen concentrate or cryoprecipitate.

SUMMARY

Given the lack of good quality evidence, much research remains to be done. However, with a multidisciplinary multimodal perioperative strategy, the risk of bleeding can be decreased effectively.

A Review of Romiplostim Mechanism of Action and Clinical Applicability

Thrombocytopenia results from a variety of conditions, including radiation, chemotherapy, autoimmune disease, bone marrow disorders, pathologic conditions associated with surgical procedures, hematopoietic stem cell transplant (HSCT), and hematologic disorders associated with severe aplastic anemia. Immune thrombocytopenia (ITP) is caused by immune reactions that accelerate destruction and reduce production of platelets. Thrombopoietin (TPO) is a critical component of platelet production pathways, and TPO receptor agonists (TPO-RAs) are important for the management of ITP by increasing platelet production and reducing the need for other treatments. Romiplostim is a TPO-RA approved for use in patients with ITP in the United States, European Union, Australia, and several countries in Africa and Asia, as well as for use in patients with refractory aplastic anemia in Japan and Korea. Romiplostim binds to and activates the TPO receptor on megakaryocyte precursors, thus promoting cell proliferation and viability, resulting in increased platelet production. Through this mechanism, romiplostim reduces the need for other treatments and decreases bleeding events in patients with thrombocytopenia. In addition to its efficacy in ITP, studies have shown that romiplostim is effective in improving platelet counts in various settings, thereby highlighting the versatility of romiplostim. The efficacy of romiplostim in such disorders is currently under investigation. Here, we review the structure, mechanism, pharmacokinetics, and pharmacodynamics of romiplostim. We also summarize the clinical evidence supporting its use in ITP and other disorders that involve thrombocytopenia, including chemotherapy-induced thrombocytopenia, aplastic anemia, acute radiation syndrome, perisurgical thrombocytopenia, post-HSCT thrombocytopenia, and liver disease.

Clinical overview and practical considerations for optimizing romiplostim therapy in patients with immune thrombocytopenia

The fundamental treatment goal for patients with immune thrombocytopenia (ITP) is reduced or ameliorated bleeding. Although various treatment options exist for the management of ITP, recent advances have led to the approval of three thrombopoietin receptor agonists (TPO-RAs; romiplostim, eltrombopag, and avatrombopag) in the United States and European Union. Current treatment guidelines for ITP indicate that medical therapy is preferred over surgical therapy and support the use of TPO-RAs as early as 3 months after disease onset. More recent data are available on the use of romiplostim in patients who have had ITP for <1 year, and romiplostim is now indicated for the treatment of adults who have not responded adequately to initial treatment, as well as children aged ≥1 year who have had ITP for ≥6 months. Here we review the role of romiplostim in the management of ITP, with a focus on efficacy and safety data, emerging data on early use (beginning within 3 months of disease onset) and treatment-free remission, and practical considerations for optimal management of ITP.

Perioperative oral eltrombopag versus intravenous immunoglobulin in patients with immune thrombocytopenia: a non-inferiority, multicentre, randomised trial

BACKGROUND

Patients with immune thrombocytopenia are at risk of bleeding during surgery, and intravenous immunoglobulin is commonly used to increase the platelet count. We aimed to establish whether perioperative eltrombopag was non-inferior to intravenous immunoglobulin.

METHODS

We did a randomised, open-label trial in eight academic hospitals in Canada. Patients were aged at least 18 years, with primary or secondary immune thrombocytopenia and platelet counts less than 100 × 10⁹ cells per L before major surgery or less than 50 × 10⁹ cells per L before minor surgery. Previous intravenous immunoglobulin within 2 weeks or thrombopoietin receptor agonists within 4 weeks before randomisation were not permitted. Patients were randomly assigned to receive oral daily eltrombopag 50 mg from 21 days preoperatively to postoperative day 7 or intravenous immunoglobulin 1 g/kg or 2 g/kg 7 days before surgery. Eltrombopag dose adjustments were allowed weekly based on platelet counts. The randomisation sequence was generated by a computerised random number generator, concealed and stratified by centre and surgery type (major or minor). The central study statistician was masked to treatment allocation. The primary outcome was achievement of perioperative platelet count targets (90 × 10⁹ cells per L before major surgery or 45 × 10⁹ cells per L before minor surgery) without rescue treatment. We did intention-to-treat and per-protocol analyses using an absolute non-inferiority margin of -10%. This trial is registered with ClinicalTrials.gov, NCT01621204.

FINDINGS

Between June 5, 2013, and March 7, 2019, 92 patients with immune thrombocytopenia were screened, of whom 74 (80%) were randomly assigned: 38 to eltrombopag and 36 to intravenous immunoglobulin. Median follow-up was 50 days (IQR 49-55). By intention-to-treat analysis, perioperative platelet targets were achieved for 30 (79%) of 38 patients assigned to eltrombopag and 22 (61%) of 36 patients assigned to intravenous immunoglobulin (absolute risk difference 17·8%, one-sided lower limit of the 95% CI 0·4%; p_{non-inferiority}=0·005). In the per-protocol analysis, perioperative platelet targets were achieved for 29 (78%) of 37 patients in the eltrombopag group and 20 (63%) of 32 in the intravenous immunoglobulin group (absolute risk difference 15·9%, one-sided lower limit of the 95% CI -2·1%; p_{non-inferiority}=0·009). Two serious adverse events occurred in the eltrombopag group: one treatment-related pulmonary embolism and one vertigo. Five serious adverse events occurred in the intravenous immunoglobulin group (atrial fibrillation, pancreatitis, vulvar pain, chest tube malfunction and conversion to open splenectomy); all were related to complications of surgery. No treatment-related deaths occurred.

INTERPRETATION

Eltrombopag is an effective alternative to intravenous immunoglobulin for perioperative treatment of immune thrombocytopenia. However, treatment with eltrombopag might increase risk of thrombosis. The decision to choose one treatment over the other will depend on patient preference, resource limitations, cost, and individual risk profiles.

FUNDING

GlaxoSmithKline and Novartis.

Thrombopoietin-receptor agonists in perioperative treatment of patients with chronic liver disease

Thrombocytopenia is a multifactorial disorder that is common in patients with chronic liver disease (CLD), leading to challenging perioperative planning. As thrombocytopenia in CLD is associated with thrombopoietin (TPO) deficiency, the use of TPO-receptor agonists (TPO-RAs) to increase platelet counts is a promising approach. This has led to the development of various TPO-RAs, including romiplostim, eltrombopag, avatrombopag, and lusutrombopag. Of these, only avatrombopag and lusutrombopag are approved by the United States Food and Drug Administration for the perioperative treatment of thrombocytopenia in patients with CLD. Platelet transfusion is commonly used for the clinical management of thrombocytopenia in patients with CLD undergoing invasive procedures. However, the limitations and possible risks of transfusion, including short duration of efficacy, development of antiplatelet antibodies, risk of infections and such complications as transfusion-related acute lung injury or circulatory overload, and possibility of refractoriness, limit its use. Moreover, there is no consensus among guidelines as to the platelet count at which transfusions are indicated. Results from studies using TPO-RAs perioperatively in patients with thrombocytopenia and CLD are promising and provide an alternative to platelet transfusions in the pre- and post-operative setting. These TPO-RAs are the subject of this review, with focus on their use in the perioperative setting in patients with thrombocytopenia, associated supporting clinical trials, efficacy and safety data, and their use with respect to platelet transfusions.

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.

Transfusion-related Acute Lung Injury in the Perioperative Patient

Transfusion-related acute lung injury is a leading cause of death associated with the use of blood products. Transfusion-related acute lung injury is a diagnosis of exclusion which can be difficult to identify during surgery amid the various physiologic and pathophysiologic changes associated with the perioperative period. As anesthesiologists supervise delivery of a large portion of inpatient prescribed blood products, and since the incidence of transfusion-related acute lung injury in the perioperative patient is higher than in nonsurgical patients, anesthesiologists need to consider transfusion-related acute lung injury in the perioperative setting, identify at-risk patients, recognize early signs of transfusion-related acute lung injury, and have established strategies for its prevention and treatment.

Romiplostim as a transfusion saving strategy in 20 patients after heart or lung transplantation: a single centre before-after pilot study

BACKGROUND

Thrombocytopenia is a common disorder after heart or lung transplantation. Platelet transfusion is often required to maintain haemostasis but represents a specific cause of morbidity and mortality in this setting including alloimmunisation and graft rejection.

STUDY DESIGN AND METHODS

As part of a health-care quality improvement project, in a single-centre before-after pilot study, the relevance of a platelet transfusion saving strategy based on romiplostim administration after transplantation was assessed in patients with platelet count <100 × 10⁹/L. Transfusions on days 28 and 90 were compared using propensity matched score for adjustment of demographic characteristics at baseline. The primary outcome was platelet transfusion until day 28 after transplantation.

RESULTS

Ninety-three patients were analysed (73 before vs. 20 after). The median [interquartile range] number of platelet concentrate was 1 [0;4.0] before versus 0.5 [0;2.0] in the after period, mean difference 0.5 confidence interval 95% [-0.7 to 1.7], p = 0.39. On day 28, median [interquartile range] red blood cell transfusion was significantly higher in the before versus the after period, 7 [2.0;13.5] versus 6 [1.5;8.5], mean difference 3.2 CI 95% [0.4-6.0], p = 0.02. At 6 months, the rate of patients with de novo anti-human leukocyte antigen alloimmunisation was 45% before versus 53% in the after period (p = 0.56). Deep venous thrombosis was detected in nine patients (12%) before versus seven patients (35%) in the after period (p = 0.04).

CONCLUSION

Romiplostim did not significantly reduce platelet transfusion after heart or lung transplantation. Its relevance and safety in a global transfusion strategy remains to be studied in this setting in a large randomised study.

Considerations for Medications Commonly Utilized in the Oncology Population in the Intensive Care Unit

An increasing number of oncologic patients are presenting to the intensive care unit with complications from both their chronic disease states and cancer therapies due to improved survival rates. The management of these patients is complex due to immunosuppression (from the malignancy and/or treatment), metabolic complications, and diverse medication regimens with the potential for significant drug-drug interactions and overlapping adverse effects. This chapter will provide clinicians with an overview of non-chemotherapy medications frequently encountered in the critically ill oncologic patient, with a focus on practical considerations.

Thrombopoietin receptor agonists for preparing adult patients with immune thrombocytopenia to splenectomy: results of a retrospective, observational GIMEMA study

In patients with immune thrombocytopenia (ITP) refractory to corticosteroids and intravenous immunoglobulins (IVIG), splenectomy may result at higher risk of peri-operative complications and, for this reason, potentially contraindicated. The thrombopoietin receptor agonists (TPO-RAs) romiplostim and eltrombopag have shown high therapeutic activity in primary ITP, but data of efficacy and safety regarding their use in preparation for splenectomy are missing. Thirty-one adult patients, median age 50 years, with corticosteroids and/or IVIG refractory persistent and chronic ITP who were treated with TPO-RAs (romiplostim= 24; eltrombopag= 7) with the aim to increase platelet count and allow a safer execution of splenectomy were retrospectively evaluated. Twenty-four patients (77%) responded to the use of TPO-RAs with a median platelet count that increased from 11 × 10(9) /L before starting TPO-RAs to 114 × 10(9) /L pre-splenectomy, but a concomitant treatment with corticosteroids and/or IVIG was required in 19 patients. Twenty-nine patients underwent splenectomy while two patients who responded to TPO-RAs subsequently refused surgery. Post-splenectomy complications were characterized by two Grade 3 thrombotic events (1 portal vein thrombosis in the patient with previous history of HCV hepatitis and 1 pulmonary embolism), with a platelet count at the time of thrombosis of 260 and 167 × 10(9) /L, respectively and one Grade 3 infectious event. TPO-RAs may represent a therapeutic option to improve platelet count and reduce the risk of peri-operative complications in ITP candidates to splenectomy. An increased risk of post-splenectomy thromboembolic events cannot be ruled out and thromboprophylaxis with low-molecular weight heparin is generally recommended.