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Kakkar AK, Dahiya N. Bedaquiline for the treatment of resistant tuberculosis: Promises and pitfalls. Tuberculosis (Edinb) 2014; 94:357-62. [DOI: 10.1016/j.tube.2014.04.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 04/06/2014] [Indexed: 10/25/2022]
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Kakkar AK. GLP-1 receptor agonists and the risk of colorectal cancer. Med Hypotheses 2014; 82:796. [DOI: 10.1016/j.mehy.2014.03.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 03/24/2014] [Indexed: 11/17/2022]
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Kakkar AK, Dahiya N. Factors Affecting Choice of Future Specialty among Medical Students. NORTH AMERICAN JOURNAL OF MEDICAL SCIENCES 2014; 6:181-2. [PMID: 24843852 PMCID: PMC4024586 DOI: 10.4103/1947-2714.131247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kakkar AK, Balakrishnan S. Obinutuzumab for chronic lymphocytic leukemia: promise of the first treatment approved with breakthrough therapy designation. J Oncol Pharm Pract 2014; 21:358-63. [PMID: 24827578 DOI: 10.1177/1078155214534868] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Obinutuzumab (also known as GA101, afutuzumab, Gazyva) is a humanized, glycoengineered type II monoclonal antibody targeted against CD20. The US Food and Drug Administration has approved obinutuzumab for use with chlorambucil in patients with previously untreated chronic lymphocytic leukemia. The drug is the first treatment to receive approval under the agency's breakthrough therapy designation, a program intended to facilitate and expedite the review and development of therapies for serious and life-threatening conditions. In preclinical studies, obinutuzumab has showed superior efficacy, as compared with rituximab, by inducing direct cell death and increased antibody-dependent cellular cytotoxicity activity with less complement-dependent cytotoxicity. Regulatory approval of obinutuzumab is based on a phase III (CLL11) study that demonstrated improved outcomes with a combination of obinutuzumab with chlorambucil in previously untreated patients with chronic lymphocytic leukemia and comorbidities. Obinutuzumab plus chlorambucil induced deeper and longer remissions than rituximab plus chlorambucil combination as evidenced by prolongation of progression-free survival and higher complete response and molecular response rates. Marketing applications for obinutuzumab have also been submitted to other regulatory authorities including the European Medicines Agency.
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Kumar Kakkar A, Dahiya N. The evolving drug development landscape: from blockbusters to niche busters in the orphan drug space. Drug Dev Res 2014; 75:231-4. [PMID: 24829189 DOI: 10.1002/ddr.21176] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Accepted: 03/25/2014] [Indexed: 11/10/2022]
Abstract
Strategy, Management and Health Policy Large pharmaceutical companies have traditionally focused on the development of blockbuster drugs that target disease states with large patient populations. However, with large-scale patent expirations and competition from generics and biosimilars, anemic pipelines, escalating clinical trial costs, and global health-care reform, the blockbuster model has become less viable. Orphan drug initiatives and the incentives accompanied by these have fostered renewed research efforts in the area of rare diseases and have led to the approval of more than 400 orphan products. Despite targeting much smaller patient populations, the revenue-generating potential of orphan drugs has been shown to be huge, with a greater return on investment than non-orphan drugs. The success of these "niche buster" therapeutics has led to a renewed interest from "Big Pharma" in the rare disease landscape. This article reviews the key drivers for orphan drug research and development, their profitability, and issues surrounding the emergence of large pharmaceutical firms into the orphan drug space.
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Nicolaides AN, Fareed J, Kakkar AK, Comerota AJ, Goldhaber SZ, Hull R, Myers K, Samama M, Fletcher J, Kalodiki E, Bergqvist D, Bonnar J, Caprini JA, Carter C, Conard J, Eklof B, Elalamy I, Gerotziafas G, Geroulakos G, Giannoukas A, Greer I, Griffin M, Kakkos S, Lassen MR, Lowe GD, Markel A, Prandoni P, Raskob G, Spyropoulos AC, Turpie AG, Walenga JM, Warwick D. Prevention and treatment of venous thromboembolism--International Consensus Statement. INT ANGIOL 2013; 32:111-260. [PMID: 24402349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The aim of this document is to provide a clear and concise account of the evidence regarding efficacy or harm for various methods available to prevent and manage venous thromboembolism (VTE).
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Lassen MR, Gent M, Kakkar AK, Eriksson BI, Homering M, Berkowitz SD, Turpie AGG. The effects of rivaroxaban on the complications of surgery after total hip or knee replacement: results from the RECORD programme. ACTA ACUST UNITED AC 2013; 94:1573-8. [PMID: 23109641 DOI: 10.1302/0301-620x.94b11.28955] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Post-operative complications after total hip or knee replacement can delay recovery, prolong hospitalisation, increase rates of re-admission and, in the most severe cases, lead to long-term disability or even death. In this analysis of pooled data from four large, randomised, phase III clinical trials that compared the oral, direct Factor Xa inhibitor rivaroxaban with subcutaneous enoxaparin for the prevention of venous thromboembolism after total hip or knee replacement (n = 12,729), the incidence of complications, including bleeding and adverse events related to surgery (such as wound infection, wound dehiscence and haemarthrosis) are reported. Interventions and procedures relating to surgery are also compared between the groups. Bleeding events, including excessive wound haematoma and surgical-site bleeding, occurred at similar rates in the rivaroxaban and enoxaparin groups. Over the total study duration, adverse surgical events occurred at a similar rate in the rivaroxaban group compared with the enoxaparin group after total knee replacement (2.26% vs. 2.69%, respectively) and total hip replacement (1.48% vs. 1.65%, respectively). Blood loss, wound drainage and transfusion requirements were also similar between the two groups. This analysis shows that the incidence of adverse surgical events with rivaroxaban was similar to enoxaparin.
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Debourdeau P, Farge D, Beckers M, Baglin C, Bauersachs RM, Brenner B, Brilhante D, Falanga A, Gerotzafias GT, Haim N, Kakkar AK, Khorana AA, Lecumberri R, Mandala M, Marty M, Monreal M, Mousa SA, Noble S, Pabinger I, Prandoni P, Prins MH, Qari MH, Streiff MB, Syrigos K, Büller HR, Bounameaux H. International clinical practice guidelines for the treatment and prophylaxis of thrombosis associated with central venous catheters in patients with cancer. J Thromb Haemost 2013; 11:71-80. [PMID: 23217208 DOI: 10.1111/jth.12071] [Citation(s) in RCA: 201] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
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.
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Farge D, Debourdeau P, Beckers M, Baglin C, Bauersachs RM, Brenner B, Brilhante D, Falanga A, Gerotzafias GT, Haim N, Kakkar AK, Khorana AA, Lecumberri R, Mandala M, Marty M, Monreal M, Mousa SA, Noble S, Pabinger I, Prandoni P, Prins MH, Qari MH, Streiff MB, Syrigos K, Bounameaux H, Büller HR. International clinical practice guidelines for the treatment and prophylaxis of venous thromboembolism in patients with cancer. J Thromb Haemost 2013; 11:56-70. [PMID: 23217107 DOI: 10.1111/jth.12070] [Citation(s) in RCA: 383] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
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.
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Patil S, Kaza RCM, Kakkar AK, Chamberlain RS. Small cell carcinoma of the renal pelvis: a case report and review of the literature. ISRN UROLOGY 2011; 2011:786505. [PMID: 22084805 PMCID: PMC3195810 DOI: 10.5402/2011/786505] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 03/12/2011] [Indexed: 12/18/2022]
Abstract
Extrapulmonary small cell carcinoma occurs in nearly all organs except the central nervous system and the liver. We are presenting a case of renal small cell carcinoma (SCC) with two unique characters. A 75-year-old patient was evaluated for back pain with no other complaints. Magnetic Resonance (MR) imaging of the abdomen revealed homogeneous tumor in the left renal pelvis extending beyond the kidney. Metastatic workup was negative. A left nephroureterectomy was performed. Histopathology and immunohistochemistry revealed a small cell carcinoma of the renal pelvis. The patient declined adjuvant therapy and died 2 months after surgery due to unrelated causes. After comprehensive worldwide literature search, we found 13 cases of SCC of the renal pelvis, including the current case. The mean age was 61.6 years (37–83), with a M : F ratio of 1 : 1.8. The average duration of symptoms was 71.4 days (21–168). Gross hematuria was the most common symptom (69.2%) followed by pain (61.5%). Adjuvant chemotherapy was provided to 4 patients (30.7%), and neoadjuvant to 1 patient. The median survival of patients who did and did not receive chemotherapy was 5.5 months (3–8) and 6 months (2–31), respectively, P < .50. In conclusion, renal SCC (both parenchymal and pelvic SCC) is a rapidly fatal disease with a median survival of ≤8 months.
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Singh M, Mandal S, Kakkar AK, Khurana N, Garg A. Mixed corticomedullary tumour with myelolipoma: a rare coexistence. Pathology 2011; 42:589-91. [PMID: 20854083 DOI: 10.3109/00313025.2010.508741] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
Venous thromboembolism is a common complication in patients with malignant disease. The development of symptomatic thromboembolism is associated with a poor prognosis for patients with cancer. Retrospective analysis of studies comparing unfractionated heparin with low-molecular-weight heparin (LMWH) for the initial treatment of deep vein thrombosis indicated improved survival for cancer patients receiving LMWH therapy. Prospective studies exposing cancer patients to LMWH therapy, in the absence of established thrombosis, suggest that survival may be prolonged in these patients after LMWH exposure. Ongoing studies, with careful attention to distribution of prognostic variables for cancer outcome, will help to answer the question regarding whether LMWH may indeed be used for this indication.
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Eriksson BI, Kakkar AK, Turpie AGG, Gent M, Bandel TJ, Homering M, Misselwitz F, Lassen MR. Oral rivaroxaban for the prevention of symptomatic venous thromboembolism after elective hip and knee replacement. ACTA ACUST UNITED AC 2009; 91:636-44. [PMID: 19407299 DOI: 10.1302/0301-620x.91b5.21691] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A once-daily dose of rivaroxaban 10 mg, an oral, direct Factor Xa inhibitor, was compared with enoxaparin 40 mg subcutaneously once daily for prevention of venous thromboembolism in three studies of patients undergoing elective hip and knee replacement (RECORD programme). A pooled analysis of data from these studies (n = 9581) showed that rivaroxaban was more effective than enoxaparin in reducing the incidence of the composite of symptomatic venous thromboembolism and all-cause mortality at two weeks (0.4% vs 0.8%, respectively, odds ratio 0.44; 95% confidence interval 0.23 to 0.79; p = 0.005), and at the end of the planned medication period (0.5% vs 1.3%, respectively; odds ratio 0.38; 95% confidence interval 0.22 to 0.62; p < 0.001). The rate of major bleeding was similar at two weeks (0.2% for both) and at the end of the planned medication period (0.3% vs 0.2%). Rivaroxaban started six to eight hours after surgery was more effective than enoxaparin started the previous evening in preventing symptomatic venous thromboembolism and all-cause mortality, without increasing major bleeding.
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Rehan HS, Chopra D, Kakkar AK. Physician's guide to pharmacovigilance: terminology and causality assessment. Eur J Intern Med 2009; 20:3-8. [PMID: 19237084 DOI: 10.1016/j.ejim.2008.04.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 03/29/2008] [Accepted: 04/25/2008] [Indexed: 01/22/2023]
Abstract
Adverse drug events can range from mild to life threatening reactions resulting in inconvenience or serious morbidity and mortality besides being a financial burden on the society. However clinicians often do not recognize this drug related harm. The terms used to describe these events with medication use cause much confusion. Moreover manifestations of adverse drug reactions can be non-specific making it difficult to differentiate from current illness. To determine the likelihood of relationship between the drug and the event assessment of causality is done. The purpose of this article is to review and clarify the terms encompassing the discipline of pharmacovigilance and also to outline the steps in causality assessment with the help of an actual case report.
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Varghese P, Gattuso JM, Mostafa AIH, Abdel-Rahman AT, Shenton KC, Ryan DA, Jones JL, Wells CA, Mair G, Kakkar AK, Carpenter R. The role of radiotherapy in treating small early invasive breast cancer. EUROPEAN JOURNAL OF SURGICAL ONCOLOGY 2008; 34:369-76. [PMID: 17560754 DOI: 10.1016/j.ejso.2007.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2007] [Accepted: 04/19/2007] [Indexed: 11/22/2022]
Abstract
AIM The aim of the study was to identify if radiotherapy can be safely avoided in a selected subgroup of largely screening detected small invasive breast cancer. METHODS One hundred and eighty-eight patients with node negative invasive early breast cancer < or =1cm (< or =T1b) treated in our centre between 1990 and 2004 were retrospectively followed for local, regional and distant recurrences. Treatment involved adequate local excision by breast conserving surgery (BCS). Axillary staging was performed by a four node axillary sampling until 2000, following which sentinel lymph node sampling was employed. All sections were assessed histologically by haematoxylin and eosin stained sections. The inked margins were reported as being involved, close and clear. Radiotherapy (RT) was employed only if the resected margins were inadequate, and in those with involved axillary nodes who refused further completion axillary clearance. RESULTS Ninety-four patients (Group A) had BCS alone and 79 patients (Group B) had both BCS and RT. There was no ipsilateral breast tumour recurrence (IBTR) in 88 patients in Group A, corresponding to an actuarial freedom from IBTR of 96%, 91% and 88.1% at 5 years, 8 years and 9 years. In Group B, there was no IBTR in 75 patients corresponding to an actuarial freedom from IBTR of 97%, 94.9% and 90.6% at 5 years, 8 years and 10 years. CONCLUSION Our experience over 14 years has shown that it is possible to safely avoid radiotherapy in a selected subgroup of small invasive breast cancer.
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Dahl OE, Borris LC, Bergqvist D, Schnack Rasmussen M, Eriksson BI, Kakkar AK, Colwell CW, Caprini JA, Fletcher J, Friedman RJ, Lassen MR, Frostick SP, Sakon M, Kwong LM, Kakkar VV. Major joint replacement. A model for antithrombotic drug development: from proof-of-concept to clinical use. INT ANGIOL 2008; 27:60-67. [PMID: 18277341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
AIM Development of antithrombotic compounds has traditionally been performed in patients undergoing total hip and knee replacement surgery. A high number of asymptomatic deep-vein thromboses are radiologically detectable, and bleeding and other adverse events (AE) are easy to observe. However, standardization of study procedures and endpoints in early proof-of-concept studies and late pure clinical endpoint studies has been lacking. This has made comparison between studies difficult, economic analyses speculative and potential benefits of applying the drug regimen in non-selected patients uncertain. In this paper, the International Surgical Thrombosis Forum proposes a strategy for the clinical investigation of new pharmacological agents for the prophylaxis of postoperative thrombotic events. METHODS First, dose titration safety studies of short duration, in highly selected patients using objective venographic endpoints are recommended. Bleeding should be divided into the quantified volume of surgical bleeding and other adjudicated clinical bleeding events. The number of AE should be described for each dose step and classified according to International Coding of Diagnoses (ICD). Second, a dose confirmatory study of moderate exposure period and sufficient follow-up time is recommended. The exclusion criteria should be restricted to contraindications of the compared drugs and technical procedure. RESULTS The efficacy, bleeding and AE should be similar to those used in dose-titration studies. In addition, the failure rate of the drug to exert its effect and the net clinical benefit should be calculated. CONCLUSION Finally, trials with simple clinical endpoints and long follow-up should be conducted to evaluate the potential benefits of the drug-regimen in non-selected populations.
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Schellong SM, Beyer J, Kakkar AK, Halbritter K, Eriksson BI, Turpie AGG, Misselwitz F, Kälebo P. Ultrasound screening for asymptomatic deep vein thrombosis after major orthopaedic surgery: the VENUS study. J Thromb Haemost 2007; 5:1431-7. [PMID: 17419763 DOI: 10.1111/j.1538-7836.2007.02570.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Venography is currently used to assess the incidence of deep vein thrombosis (DVT) in dose-finding and confirmatory trials of new antithrombotic agents. Centrally adjudicated, complete compression ultrasound (CCUS) could be a non-invasive alternative to venography. OBJECTIVES A substudy of two, similarly designed, phase IIb trials of a novel, oral anticoagulant for the prevention of venous thromboembolism after elective hip or knee arthroplasty was undertaken to validate CCUS against venography. PATIENTS/METHODS Patients received study drugs until mandatory, bilateral venography was performed 7 +/- 2 days after surgery. CCUS was performed within 24 h after venography by sonographers blinded to the venography result. Sonographers were trained and certified for the standardized examination and documentation procedure. Venograms and sonograms were adjudicated centrally at different sites by two independent readers; discrepancies between readers were resolved by consensus. RESULTS A total of 1104 matching pairs of evaluable venograms and sonograms were obtained from the participants of the two trials (n = 1435): 19% of venograms and 20% of sonograms were not evaluable. The observed frequency of any DVT was 18.9% with venography and 11.5% with CCUS. Sensitivity of CCUS compared with venography was 31.1% for any DVT (95% confidence interval 23.4, 38.9), 21.0% (2.7, 39.4) for proximal DVT, and 30.8% (23.1, 38.6) for distal DVT. The figures for specificity were 93.0% (91.0, 95.1), 98.7% (98.0, 99.5), and 93.3% (91.5, 95.3), respectively. CONCLUSIONS Based on these results, centrally adjudicated CCUS will be unable to replace venography for DVT screening early after major orthopaedic surgery in studies evaluating anticoagulant drugs.
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Parakh R, Kakkar VV, Kakkar AK. Management of venous thromboembolism. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2007; 55:49-70. [PMID: 17444345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
INTRODUCTION Venous Thromboembolism is an important healthcare problem the world over, resulting in significant morbidity, mortality and resource expenditure. The rationale for use of thromboprophylaxis is based on solid principles and scientific evidence. Indian perspective on this topic is lacking due to the non-availability of published Indian data. This document reviews the available International and Indian data and discusses the relevance of recommendations for prevention and management of Venous Thromboembolism (VTE) in the Indian context. MATERIALS AND METHODS Meetings of various specialists from different Indian hospitals in the field of Gastrointestinal Surgery, General and Vascular Surgery, Hematology, Intensive Care, Obstetrics and Gynecology, Oncology and Orthopedics were held in the months of August 2005 to January 2006. The guidelines published by American College of Chest Physicians (ACCP), the International Union of Angiology (IUA), and the Royal College of Obstetricians and Gynecologists (RCOG), were discussed during these meetings. The relevance of these guidelines and the practical implications of following these in a developing country like India were also discussed. Any published data from India was collected from data base searches and the results, along with personal experiences of the participating specialists were discussed. The experiences and impressions of the experts during these meetings have been included in this document. Data from recent sources (International Union of Angiology and the National Comprehensive Cancer Network (NCCN) Practice guidelines in Oncology on Venous thromboembolic disease) was subsequently also included in this document. RESULTS The suggestions formulated in this document are practical, and would intend to serve as a useful practical reference. CONCLUSIONS A number of unanswered questions remain in the field of thromboprophylaxis, and carefully designed research protocols may help answer some of these. Implementation of the suggestions outlined in the document remains to be studied in the Indian context.
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Eriksson BI, Borris L, Dahl OE, Haas S, Huisman MV, Kakkar AK, Misselwitz F, Kälebo P. Oral, direct Factor Xa inhibition with BAY 59-7939 for the prevention of venous thromboembolism after total hip replacement. J Thromb Haemost 2006; 4:121-8. [PMID: 16409461 DOI: 10.1111/j.1538-7836.2005.01657.x] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Joint replacement surgery is an appropriate model for dose-ranging studies investigating new anticoagulants. OBJECTIVES To assess the efficacy and safety of a novel, oral, direct factor Xa (FXa) inhibitor--BAY 59-7939--relative to enoxaparin in patients undergoing elective total hip replacement. METHODS In this double-blind, double-dummy, dose-ranging study, patients were randomized to oral BAY 59-7939 (2.5, 5, 10, 20, or 30 mg b.i.d.), starting 6-8 h after surgery, or s.c. enoxaparin 40 mg once daily, starting on the evening before surgery. Treatment was continued until mandatory bilateral venography was performed 5-9 days after surgery. RESULTS Of 706 patients treated, 548 were eligible for the primary efficacy analysis. The primary efficacy endpoint was the incidence of any deep vein thrombosis, non-fatal pulmonary embolism, and all-cause mortality; rates were 15%, 14%, 12%, 18%, and 7% for BAY 59-7939 2.5, 5, 10, 20, and 30 mg b.i.d., respectively, compared with 17% for enoxaparin. The primary efficacy analysis did not demonstrate any significant trend in dose-response relationship for BAY 59-7939. The primary safety endpoint was major, postoperative bleeding; there was a significant increase in the frequency of events with increasing doses of BAY 59-7939 (P = 0.045), but no significant differences between individual BAY 59-7939 doses and enoxaparin. CONCLUSIONS When efficacy and safety were considered together, the oral, direct FXa inhibitor BAY 59-7939, at 2.5-10 mg b.i.d., compared favorably with enoxaparin for the prevention of venous thromboembolism in patients undergoing elective total hip replacement.
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Patel HB, Nasir FA, Nash GF, Scully MF, Kakkar AK. Enhanced angiogenesis following allogeneic blood transfusion. ACTA ACUST UNITED AC 2004; 26:129-35. [PMID: 15053807 DOI: 10.1111/j.1365-2257.2004.00589.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Blood transfusions are associated with recurrence of solid cancers. Angiogenesis is essential for cancer growth. Our aim was to determine for the first time in a prospective cohort study the effect of prestorage allogeneic leucodepleted SAGM (saline, adenine, glucose, mannitol) red cell transfusion on angiogenic factor levels and in vitro angiogenesis. Forty pretransfusion adult hospital inpatients were selected consecutively. Serum vascular endothelial growth factor (VEGF) and endostatin were measured in each patient before and after prestorage allogeneic leucodepleted SAGM red cell transfusion. All samples were exposed to an in vitro endothelial cell proliferation assay and 10 sample groups were also exposed to an in vitro whole angiogenesis assay. The median number of units transfused was 2 (minimum-maximum, 2-4). Twenty-nine (73%) patients had a rise in VEGF, with an overall increase of 118 pg/ml (quartiles -5, 306; P < 0.01). Twenty-eight (70%) patients had a decrease in endostatin, with an overall reduction of 1.2 ng/ml (quartiles 4.0, 0.0; P = 0.017). There was an overall 33% increase in endothelial cell proliferation (P < 0.01) and a 9.4% increase in in vitro whole assay angiogenesis (P < 0.01). Prestorage allogeneic leucodepleted SAGM red cell transfusions are associated with a favourable angiogenic factor imbalance and an elevation in in vitro angiogenesis.
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