Ramón Lecumberri

International clinical practice guidelines for the treatment and prophylaxis of venous thromboembolism in patients with cancer

Summary.  Background: Guidelines addressing the management of venous thromboembolism (VTE) in cancer patients are heterogeneous and their implementation has been suboptimal worldwide. Objectives: To establish a common international consensus addressing practical, clinically relevant questions in this setting. Methods: An international consensus working group of experts was set up to develop guidelines according to an evidence‐based medicine approach, using the GRADE system. Results: For the initial treatment of established VTE: low‐molecular‐weight heparin (LMWH) is recommended [1B]; fondaparinux and unfractionated heparin (UFH) can be also used [2D]; thrombolysis may only be considered on a case‐by‐case basis [Best clinical practice (Guidance)]; vena cava filters (VCF) may be considered if contraindication to anticoagulation or pulmonary embolism recurrence under optimal anticoagulation; periodic reassessment of contraindications to anticoagulation is recommended and anticoagulation should be resumed when safe; VCF are not recommended for primary VTE prophylaxis in cancer patients [Guidance]. For the early maintenance (10 days to 3 months) and long‐term (beyond 3 months) treatment of established VTE, LMWH for a minimum of 3 months is preferred over vitamin K antagonists (VKA) [1A]; idraparinux is not recommended [2C]; after 3–6 months, LMWH or VKA continuation should be based on individual evaluation of the benefit‐risk ratio, tolerability, patient preference and cancer activity [Guidance]. For the treatment of VTE recurrence in cancer patients under anticoagulation, three options can be considered: (i) switch from VKA to LMWH when treated with VKA; (ii) increase in LMWH dose when treated with LMWH, and (iii) VCF insertion [Guidance]. For the prophylaxis of postoperative VTE in surgical cancer patients, use of LMWH o.d. or low dose of UFH t.i.d. is recommended; pharmacological prophylaxis should be started 12–2 h preoperatively and continued for at least 7–10 days; there are no data allowing conclusion that one type of LMWH is superior to another [1A]; there is no evidence to support fondaparinux as an alternative to LMWH [2C]; use of the highest prophylactic dose of LMWH is recommended [1A]; extended prophylaxis (4 weeks) after major laparotomy may be indicated in cancer patients with a high risk of VTE and low risk of bleeding [2B]; the use of LMWH for VTE prevention in cancer patients undergoing laparoscopic surgery may be recommended as for laparotomy [Guidance]; mechanical methods are not recommended as monotherapy except when pharmacological methods are contraindicated [2C]. For the prophylaxis of VTE in hospitalized medical patients with cancer and reduced mobility, we recommend prophylaxis with LMWH, UFH or fondaparinux [1B]; for children and adults with acute lymphocytic leukemia treated with l‐asparaginase, depending on local policy and patient characteristics, prophylaxis may be considered in some patients [Guidance]; in patients receiving chemotherapy, prophylaxis is not recommended routinely [1B]; primary pharmacological prophylaxis of VTE may be indicated in patients with locally advanced or metastatic pancreatic [1B] or lung [2B] cancer treated with chemotherapy and having a low risk of bleeding; in patients treated with thalidomide or lenalidomide combined with steroids and/or chemotherapy, VTE prophylaxis is recommended; in this setting, VKA at low or therapeutic doses, LMWH at prophylactic doses and low‐dose aspirin have shown similar effects; however, the efficacy of these regimens remains unclear [2C]. Special situations include brain tumors, severe renal failure (CrCl < 30 mL min−1), thrombocytopenia and pregnancy. Guidances are provided in these contexts. Conclusions: Dissemination and implementation of good clinical practice for the management of VTE, the second cause of death in cancer patients, is a major public health priority.

International clinical practice guidelines for the treatment and prophylaxis of thrombosis associated with central venous catheters in patients with cancer

Summary.  Background: Although long‐term indwelling central venous catheters (CVCs) may lead to pulmonary embolism (PE) and loss of the CVC, there is lack of consensus on management of CVC‐related thrombosis (CRT) in cancer patients and heterogeneity in clinical practices worldwide. Objectives: To establish common international Good Clinical Practices Guidelines (GCPG) for the management of CRT in cancer patients. Methods: An international working group of experts was set up to develop GCPG according to an evidence‐based medicine approach, using the GRADE system. Results: For the treatment of established CRT in cancer patients, we found no prospective randomized studies, two non‐randomized prospective studies and one retrospective study examining the efficacy and safety of low‐molecular‐weight heparin (LMWH) plus vitamin K antagonists (VKAs). One retrospective study evaluated the benefit of CVC removal and two small retrospective studies were on thrombolytic drugs. For the treatment of symptomatic CRT, anticoagulant treatment (AC) is recommended for a minimum of 3 months; in this setting, LMWHs are suggested. VKAs can also be used, in the absence of direct comparisons of these two types of anticoagulants in this setting [Guidance]. The CVC can be kept in place if it is functional, well‐positioned and non‐infected and there is good resolution under close surveillance; whether the CVC is kept or removed, no standard approach in terms of AC duration has been established [Guidance]. For the prophylaxis of CRT in cancer patients, we found six randomized studies investigating the efficacy and safety of VKA vs. placebo or no treatment, one on the efficacy and safety of unfractionnated heparin, six on the value of LMWH, one double‐blind randomized and one non randomized study on thrombolytic drugs and six meta‐analyses of AC and CVC thromboprophylaxis. Type of catheter (open‐ended like the Hickman® catheter vs. closed‐ended catheter with a valve like the Groshong® catheter), its position (above, below or at the junction of the superior vena cava and the right atrium) and method of placement may influence the onset of CRT on the basis of six retrospective trials, four prospective non‐randomized trials, three randomized trials and one meta‐analysis. In light of these data: use of AC for routine prophylaxis of CRT is not recommended [1A]; a CVC should be inserted on the right side, in the jugular vein, and distal extremity of the CVC should be located at the junction of the superior vena cava and the right atrium [1A]. Conclusion: Dissemination and implementation of these international GCPG for the prevention and treatment of CRT in cancer patients at each national level is a major public health priority, needing worldwide collaboration.

Venous thromboembolism during pregnancy or postpartum: Findings from the RIETE Registry

Venous thromboembolism (VTE) occurs infrequently during pregnancy, and issues concerning its natural history, prevention and therapy remain unresolved. RIETE is an ongoing registry of consecutive patients with objectively confirmed, symptomatic acute VTE. In this analysis, we compared the clinical characteristics and outcome for all enrolled pregnant and postpartum women with acute VTE, and all non-pregnant women in the same age range. Up to May 2005, 11,630 patients were enrolled in RIETE, of whom 848 (7.3%) were women aged <47 years. Of them, 72 (8.5%) were pregnant, 64 (7.5%) postpartum. Pregnant women presented less often with symptomatic pulmonary embolism (11%) than non-pregnant women (39%). VTE developed during the first trimester in 29 (40%) pregnant patients; in the second in 13; in the third in 30. Thrombophilia tests were more often positive in women who had VTE during the first trimester (odds ratio [OR]: 4.4; 95% CI: 0.9-2.4; p=0.037). Most patients in all three groups were initially treated with low-molecular-weight heparin (LMWH). As for long-term therapy, 75% of pregnant women received LMWH until delivery. There were no maternal deaths, and no pregnant patient had recurrence or bled before delivery. However, after delivery one patient (1.4%) developed recurrent thrombosis, four (5.6%) had major bleeding. In conclusion, VTE developed during the first trimester in 40% of the pregnant women, thus suggesting that thromboprophylaxis, when indicated during pregnancy, should start in the first trimester. No patient showed recurrence or bled before delivery, but after delivery the risk of bleeding exceeded the risk of recurrences.

Thrombophilia testing in patients with venous thromboembolism. Findings from the RIETE registry.

BACKGROUND There is scarce information on the management habits with regard to thrombophilia testing in patients with venous thromboembolism (VTE). PATIENTS AND METHODS RIETE is an ongoing registry of consecutive patients with symptomatic VTE. Aimed to estimate the extent to which thrombophilia test ordering patterns are consistent with the recommendations by a 2005 international consensus statement, we retrospectively compared the clinical characteristics of all patients tested for thrombophilia and those who were not tested. RESULTS Of 21367 patients enrolled, 4494 (21%) were tested for thrombophilia: 1456 (32%) tested positive, 3038 (68%) negative. The most common abnormalities were: Factor V Leiden (N=376), antiphospholipid syndrome (N=289), and prothrombin G20210A (N=263). Overall, 12740 (60%) patients met one or more criteria of the consensus statement: 7894 (37%) had a first episode of idiopathic VTE; 4013 (19%) were aged <50 years; 133 (0.6%) were pregnant women; 758 (3.5%) were using estrogens; 3375 (16%) had recurrent VTE. Of them, 3618 (28%) underwent thrombophilia tests, 34% of whom tested positive. The percentage of patients testing positive was significantly higher in those aged <50 years, with no differences between idiopathic or secondary, first episode or recurrent VTE. Finally, 876 (10%) of the 8627 (40%) patients meeting no criteria were tested. Of these, 208 (24%) tested positive. CONCLUSIONS Twenty-eight percent of patients meeting one or more criteria for thrombophilia testing, and 10% of those with no criteria were actually tested. Thus, a substantial proportion of thrombophilia ordering is not consistent with the recommendations made by the consensus statement.

Specific Antidotes in Development for Reversal of Novel Anticoagulants: A Review

In the last decade, several direct oral anticoagulants (DOAC; dabigatran, rivaroxaban, apixaban, edoxaban) have been marketed for prophylaxis and/or treatment of thromboembolism without having specific antidotes available for their reversal. Current management of bleeding associated to DOAC includes the removal of all antithrombotic medications and supportive care. Non-specific procoagulant agents (prothrombin complex concentrates and activated factor VIIa) have been used in case of serious bleeding. Currently, some specific antidotes for the DOAC are under development. Idarucizumab (BI 655075; Boehringer Ingelheim) is a fragment of an antibody (Fab), which is a specific antidote to the oral direct thrombin inhibitor dabigatran. Andexanet alfa (r-Antidote, PRT064445; Portola Pharmaceuticals) is a truncated form of enzymatically inactive factor Xa, which binds and reverses the anticoagulant action of the factor Xa inhibitors (e.g.: rivaroxaban, apixaban and edoxaban). Aripazine (PER-977, ciraparantag; Perosphere Inc.) is a synthetic small molecule (~500 Da) that reverses oral dabigatran, apixaban, rivaroxaban, as well as subcutaneous fondaparinux and LMWH in vivo. These antidotes could provide an alternative for management of life-threatening bleeding events occurring with the above-mentioned anticoagulants. In addition, the specific antidote anivamersen (RB007; Regado Biosciences Inc.) is an RNA aptamer in clinical development to reverse the anticoagulant effect of the parenteral factor IXa inhibitor pegnivacogin, which is also in development. This anticoagulant-antidote pair may provide an alternative in situations in which a fast onset and offset of anticoagulation is needed, like in patients undergoing cardiac surgery with extracorporeal circulation, as an alternative to the heparin/protamine pair. This patent review includes a description of the pharmacological characteristics of the novel specific antidotes, the available results from completed non-clinical and clinical studies and the description of ongoing clinical trials with the new compounds.

Direct oral anticoagulants in the treatment of acute venous thromboembolism: a systematic review and meta-analysis.

INTRODUCTION Acute venous thromboembolism (VTE) is a common disease associated to significant morbidity and mortality. MATERIALS AND METHODS We systematically reviewed and meta-analysed clinical outcomes with direct oral anticoagulants (DOAC: dabigatran, rivaroxaban, apixaban or edoxaban) for treatment of acute VTE. We used MEDLINE and CENTRAL, clinical trials registers, conference proceedings, and websites of regulatory agencies to identify randomised clinical trials of DOAC compared with conventional treatment [parenteral anticoagulant followed by a vitamin K antagonist (VKA)] for acute VTE. Two investigators independently extracted data. Relative risk of recurrent VTE, bleeding events, deaths and a net clinical endpoint (composite of recurrent VTE, major bleeding, and death) were estimated using a random effect meta-analysis (RevMan software). RESULTS Six trials including 27,127 patients were selected. The risk of recurrent VTE was similar with the DOAC and standard treatment (relative risk 0.91, 95% confidence interval 0.79 to 1.06). The DOAC reduced the risk of major bleeding in comparison with standard treatment (0.62, 0.45 to 0.85) (absolute risk difference, -0.6%; 95% confidence interval -1.0% to -0.3%), but there was heterogeneity across trials in the relative risk of bleeding. No between treatment differences were found in the relative risk of all-cause mortality (0.98, 0.84 to 1.14). The DOAC and conventional treatment differed on the net clinical endpoint (0.85, 0.75 to 0.97). Subgroup analyses in relevant subgroups (index pulmonary embolism, heparin lead-in, age, gender, renal function, presence of cancer), as well as sensitivity analyses, were consistent with the main analysis. CONCLUSIONS The DOAC seem as effective as, and probably safer than standard treatment of acute VTE. The relative efficacy and safety of the DOAC was consistent across a wide range of patients.

Consenso nacional sobre el diagnóstico, estratificación de riesgo y tratamiento de los pacientes con tromboembolia pulmonar

a Servicio de Neumología, Hospital de Cruces, Bilbao, España b Servicio de Medicina Interna, Hospital Germans Trias I Pujol, Badalona, España c Servicio de Medicina Interna, Hospital Universitario de Gerona Dr. Josep Trueta, Gerona, España d Servicio de Hematología, Hospital Universitario de Bellvitge, Barcelona, España e Servicio de Hematología, Clínica Universitaria de Navarra, Pamplona, España f Servicio de Cardiología, Hospital Doce de Octubre, Madrid, España g Servicio de Cardiología, Hospital Ramón y Cajal, IRYCIS, Madrid, España h Servicio de Urgencias, Hospital Clinic, Barcelona, España i Servicio de Urgencias, Hospital Clínico San Carlos, Madrid, España j Servicio de Angiología y Cirugía Vascular, Hospital Universitario de Bellvitge, Barcelona, España k Servicio de Angiología y Cirugía Vascular, Hospital Clínico Universitario, Salamanca, España l Servicio de Neumología, Hospital Ramón y Cajal, IRYCIS, Madrid, España

Recurrent venous thromboembolism in anticoagulated patients with cancer: management and short-term prognosis

Recommendations for management of cancer‐related venous thromboembolism (VTE) in patients already receiving anticoagulant therapy are based on low‐quality evidence. This international registry sought to provide more information on outcomes after a breakthrough VTE in relation to anticoagulation strategies.

New parenteral anticoagulants in development

The therapeutic armamentarium of parenteral anticoagulants available to clinicians is mainly composed by unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), fondaparinux, recombinant hirudins (i.e. bivalirudin, desirudin, lepirudin) and argatroban. These drugs are effective and safe for prevention and/or treatment of thromboembolic diseases but they have some drawbacks. Among other inconveniences, UFH requires regular anticoagulant monitoring as a result of variability in the anticoagulant response and there is a risk of serious heparin-induced thrombocytopaenia (HIT). LMWH, fondaparinux and recombinant hirudins are mainly cleared through the kidneys and their use in patients with severe renal insufficiency may be problematic. LMWH is only partially neutralized by protamine while fondaparinux and recombinant hirudins have no specific antidote. Novel anticoagulants in development for parenteral administration include new indirect activated factor Xa (FXa) inhibitors (idrabiotaparinux, ultra-low-molecular-weight heparins [semuloparin, RO-14], new LMWH [M118]), direct FXa inhibitors (otamixaban), direct FIIa inhibitors (flovagatran sodium, pegmusirudin, NU172, HD1-22), direct FXIa inhibitors (BMS-262084, antisense oligonucleotides targeting FXIa, clavatadine), direct FIXa inhibitors (RB-006), FVIIIa inhibitors (TB-402), FVIIa/tissue factor inhibitors (tifacogin, NAPc2, PCI-27483, BMS-593214), FVa inhibitors (drotrecogin alpha activated, ART-123) and dual thrombin/FXa inhibitors (EP217609, tanogitran). These new compounds have the potential to complement established parenteral anticoagulants. In the present review, we discuss the pharmacology of new parenteral anticoagulants, the results of clinical studies, the newly planned or ongoing clinical trials with these compounds, and their potential advantages and drawbacks over existing therapies.

New Anticoagulants: Focus on Venous Thromboembolism

Anticoagulation is recommended for prophylaxis and treatment of venous thromboembolism (VTE) (deep vein thrombosis and pulmonary embolism) and/or arterial thromboembolism. The therapeutic arsenal of anticoagulants available to clinicians is mainly composed by unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), fondaparinux and oral vitamin K antagonists (VKA) (i.e. warfarin and acenocumarol). These anticoagulants are effective, but they require parenteral administration (UFH, LMWH, fondaparinux) and/or frequent anticoagulant monitoring (intravenous UFH, oral VKA). Novel anticoagulants in clinical testing include orally active direct factor II inhibitors [dabigatran etexilate (BIBR 1048), AZD0837)], parenteral direct factor II inhibitors (flovagatran sodium), orally active direct factor X inhibitors [rivaroxaban (BAY 59-7939), apixaban, betrixaban, YM150, DU-176b, LY-517717, GW813893, TAK-442, PD 0348292] and new parenteral FXa inhibitors [idraparinux, idrabiotaparinux (biotinilated idraparinux; SSR 126517), ultra-low-molecular-weight heparins (ULMWH: AVE5026, RO-14)]. These new compounds have the potential to complement heparins and fondaparinux for short-term anticoagulation and/or to replace VKA for long-term anticoagulation in most patients. Dabigatran and rivaroxaban have been the firsts of the new oral anticoagulants to be licensed for the prevention of VTE after hip and knee replacement surgery. In the present review, we discuss the pharmacology of new anticoagulants, the key points necessary for interpreting the results of studies on VTE prophylaxis and treatment, the results of clinical trials testing these new compounds and their potential advantages and drawbacks over existing therapies.