Steven Gabardi

Harvard University, Cambridge, Massachusetts, United States

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Publications (66)180.74 Total impact

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    ABSTRACT: Demographic changes are associated with a steady increase of older patients with end-stage organ failure in need for transplantation. As a result, the majority of transplant recipients are currently older than 50 years, and organs from elderly donors are more frequently used. Nevertheless, the benefit of transplantation in older patients is well recognized, whereas the most frequent causes of death among older recipients are potentially linked to side effects of their immunosuppressants.Immunosenescence is a physiological part of aging linked to higher rates of diabetes, bacterial infections, and malignancies representing the major causes of death in older patients. These age-related changes impact older transplant candidates and may have significant implications for an age-adapted immunosuppression. For instance, immunosenescence is linked to lower rates of acute rejections in older recipients, whereas the engraftment of older organs has been associated with higher rejection rates. Moreover, new-onset diabetes mellitus after transplantation is more frequent in the elderly, potentially related to corticosteroids, calcineurin inhibitors, and mechanistic target of rapamycin inhibitors.This review presents current knowledge for an age-adapted immunosuppression based on both, experimental and clinical studies in and beyond transplantation. Recommendations of maintenance and induction therapy may help to improve graft function and to design future clinical trials in the elderly.
    No preview · Article · Aug 2015 · Transplantation
  • Steven Gabardi · Stefan G Tullius · Felix Krenzien
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    ABSTRACT: This review presents current knowledge of the impact of age on the pharmacokinetics of maintenance immunosuppressants. Over the past decade, there has been a steady increase in older patients on organ transplant waiting lists. As a result, the average age of transplant recipients has significantly increased. The survival and quality-of-life benefits of transplantation in the elderly population have been demonstrated. Advancing age is associated with changes in immune responses, as well as changes in drug handling. Immunosenescence is a physiological part of aging and is linked to reduced rejection rates, but also higher rates of diabetes, infections and malignancies. Physiologic changes associated with age can have a significant impact on the pharmacokinetics of the maintenance immunosuppressive agents. Taken together, these age-related changes impact older transplant candidates and may have significant implications for managing immunosuppression in the elderly. Despite the lack of formal efficacy, safety and pharmacokinetic studies of individual immunosuppressants in the elderly transplant population, there are enough data available for practitioners to be able to adequately manage their older patients. A proficient understanding of the factors that impact the pharmacokinetics of the immunosuppressants in the elderly is essential to managing these patients successfully.
    No preview · Article · Jun 2015 · Current opinion in organ transplantation
  • Karen Phillips · Prabashni Reddy · Steven Gabardi
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    ABSTRACT: The uptake of generic immunosuppressants lags comparatively to other drug classes, despite that the Food and Drug Administration (FDA) uses identical bioequivalence standards for all drugs. Transplant societies acknowledge the cost savings associated with generic immunosuppressants and support their use following heart, lung, kidney, or bone marrow transplantation. Seven studies of the pharmacokinetics or clinical efficacy of generic mycophenolate mofetil compared to the innovator product are published; all studies and products were ex-United States. Three studies did not demonstrate any pharmacokinetic differences between generic and innovator products in healthy subjects, achieving FDA bioequivalence requirements. Two studies in renal allograft recipients demonstrated no difference in area under the curves between generic and innovator products, and in one, the maximum concentration (Cmax) fell outside the FDA regulatory range. Two studies revealed no difference in acute organ rejection or graft function in renal allograft recipients. Patient surveys indicate that cost is a barrier to immunosuppressant adherence. Generics present a viable method to reduce costs to payers, patients, and health care systems. Adherence to immunosuppressants is crucial to prevent graft failure. An affordable regimen potentially confers greater adherence. Concerns regarding the presumed inferiority of generic immunosuppressants should be assuaged by regulatory requirements for bioequivalency testing, transplant society position statements, and pharmacokinetic and clinical studies. © The Author(s) 2015.
    No preview · Article · Jun 2015 · Journal of Pharmacy Practice
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    ABSTRACT: Pharmacotherapy concerns and other factors with a bearing on patient selection for kidney transplantation are discussed. The process of selecting appropriate candidates for kidney transplantation involves multidisciplinary assessment to evaluate a patient's mental, social, physical, financial, and medical readiness for successful surgery and good posttransplantation outcomes. Transplantation pharmacists can play important roles in the recognition and stratification of pharmacologic and nonpharmacologic risks in prospective kidney transplant recipients and the identification of issues that require a mitigation strategy. Key pharmacotherapy-related issues and considerations during the risk assessment process include (1) anticoagulation concerns, (2) cytochrome P-450 isoenzyme-mediated drug interactions, (3) mental health-related medication use, (4) chronic pain-related medication use, (5) medication allergies, (6) use of hormonal contraception and replacement therapy, (7) prior or current use of immunosuppressants, (8) issues with drug absorption, (9) alcohol use, (10) tobacco use, (11) active use of illicit substances, and (12) use of herbal supplements. Important areas of nonpharmacologic risk include vaccine delivery, infection prophylaxis and treatment, and socially related factors such as nonadherent behavior, communication barriers, and financial, insurance, or transportation challenges that can compromise posttransplantation outcomes. Consensus opinions of practitioners in transplantation pharmacy regarding the pharmacologic and nonpharmacologic factors that should be considered in assessing candidates for kidney transplantation are presented. Copyright © 2015 by the American Society of Health-System Pharmacists, Inc. All rights reserved.
    No preview · Article · May 2015 · American journal of health-system pharmacy: AJHP: official journal of the American Society of Health-System Pharmacists
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    ABSTRACT: IntroductionUp to 20% of renal transplant recipients (RTR) will develop human BK polyomavirus (BKPyV) viremia. BKPyV viremia is a pre-requisite of polyomavirus-associated nephropathy (PyVAN). Risk of BKPyV infections increases with immunosuppression. Currently, the only effective therapy against PyVAN is reductions in immunosuppression; but this may increase the risk of rejection. In vitro data have shown that pravastatin dramatically decreased caveolin-1 expression in human renal proximal tubular epithelial cells (HRPTEC) and suppressed BKPyV infection in these cells. Based on these data, we postulated that statin therapy may prevent the progression of BKPyV viremia to PyVANPatients and methodsA multicenter, retrospective study was conducted in adult RTR transplanted between July 2005 and March 2012. All patients with documented BKPyV viremia (viral load >500 copies/mL on 2 consecutive tests) were included. Group I consisted of patients taking a statin before the BKPyV viremia diagnosis (n = 32), and Group II had no statin exposure before or after the BKPyV viremia diagnosis (n = 36). The primary endpoint was the incidence of PyVANResultsDemographic data, transplant characteristics, and the degree of immunosuppression (i.e., induction/maintenance therapies, rejection treatment) were similar between the groups, with the exception of more diabetics in Group I. The incidence of PyVAN was comparable between the 2 groups (Group I = 28.1% vs. Group II = 41.7%; P = 0.312)Conclusions Despite the proven in vitro effectiveness of pravastatin preventing BKPyV infection in HRPTEC, statins at doses maximized for cholesterol lowering, in RTR with BKPyV viremia, did not prevent progression to PyVANThis article is protected by copyright. All rights reserved.
    No preview · Article · May 2015 · Transplant Infectious Disease
  • Sandra El Hajj · Miae Kim · Karen Phillips · Steven Gabardi
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    ABSTRACT: The overall success of organ transplantation in the 21st century has been predicated, in part, on the use of newer, more potent, and selective immunosuppressive agents. However, the high cost of lifelong immunosuppression represents a financial burden for many patients. In the past 15 years, regulatory agencies in Europe and America have approved several generic immunosuppressants. One concern is whether the conversion between innovator and generic immunosuppressants will prove to be problematic. This manuscript aims to compare and contrast the bioequivalence requirements among regulatory authorities in the USA, Europe, and Canada, evaluate published studies of generic immunosuppressants in transplant recipients, summarize consensus statements made by transplant organizations and discuss how to engage patients in discussion regarding the choice between innovator and generic immunosuppressants.
    No preview · Article · Mar 2015 · Expert Review of Clinical Immunology
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    ABSTRACT: Despite proven efficacy of prolonged cytomegalovirus (CMV) prophylaxis using valganciclovir 900 mg/day, some centers use 450 mg/day due to reported success and cost savings. This multicenter, retrospective study compared the efficacy and safety of 6 months of low-dose versus high-dose valganciclovir prophylaxis in high-risk, donor-positive/recipient-negative, renal transplant recipients (RTR). Two hundred thirty-seven high-risk RTR (low-dose group = valganciclovir 450 mg/day [n = 130]; high-dose group = valganciclovir 900 mg/day [n = s7]) were evaluated for 1-year CMV disease prevalence. Breakthrough CMV, resistant CMV, biopsy-proven acute rejection (BPAR), graft loss, opportunistic infections (OI), new-onset diabetes after transplantation (NODAT), premature valganciclovir discontinuation, renal function and myelosuppression were also assessed. Patient demographics and transplant characteristics were comparable. Induction and maintenance immunosuppression were similar, except for more early steroid withdrawal in the high-dose group. Similar proportions of patients developed CMV disease (14.6% vs 24.3%; P = 0.068); however, controlling CMV risk factor differences through multivariate logistic regression revealed significantly lower CMV disease in the low-dose group (P = 0.02; odds ratio, 0.432, 95% confidence interval, 0.211-0.887). Breakthrough and resistant CMV occurred at similar frequencies. There was no difference in renal function or rates of biopsy-proven acute rejection, graft loss, opportunistic infections, or new-onset diabetes after transplantation. The high-dose group had significantly lower mean white blood cell counts at months 5 and 6; however, premature valganciclovir discontinuation rates were similar. Low-dose and high-dose valganciclovir regimens provide similar efficacy in preventing CMV disease in high-risk RTR, with a reduced incidence of leukopenia associated with the low-dose regimen and no difference in resistant CMV. Low-dose valganciclovir may provide a significant cost avoidance benefit.
    No preview · Article · Jan 2015 · Transplantation
  • Miae Kim · Spencer T. Martin · Keri R. Townsend · Steven Gabardi
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    ABSTRACT: Antibody-mediated rejection (AMR), also known as B-cell–mediated or humoral rejection, is a significant complication after kidney transplantation that carries a poor prognosis. Although fewer than 10% of kidney transplant patients experience AMR, as many as 30% of these patients experience graft loss as a consequence. Although AMR is mediated by antibodies against an allograft and results in histologic changes in allograft vasculature that differ from cellular rejection, it has not been recognized as a separate disease process until recently. With an improved understanding about the importance of the development of antibodies against allografts as well as complement activation, significant advances have occurred in the treatment of AMR. The standard of care for AMR includes plasmapheresis and intravenous immunoglobulin that remove and neutralize antibodies, respectively. Agents targeting B cells (rituximab and alemtuzumab), plasma cells (bortezomib), and the complement system (eculizumab) have also been used successfully to treat AMR in kidney transplant recipients. However, the high cost of these medications, their use for unlabeled indications, and a lack of prospective studies evaluating their efficacy and safety limit the routine use of these agents in the treatment of AMR in kidney transplant recipients.
    No preview · Article · Jul 2014 · Pharmacotherapy
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    ABSTRACT: Rationale: The prevalence of anti-HLA antibodies in lung transplant candidates and their impact on waitlist and transplant outcomes is not known. Objectives: We examined the prevalence of pre-transplant anti-HLA antibodies at varying thresholds and evaluated their impact on outcomes before and after lung transplantation. Methods: We performed a single-center retrospective cohort study including all patients listed for lung transplantation between January 2008 and August 2012. Per protocol, transplant candidates were assessed by solid phase LABscreen mixed Class I and II and LABscreen Single Antigen assays. Measurements and Main Results: Among 224 patients, 34% had anti-HLA antibodies at MFI≥3000 (group III), while 24% had antibodies at MFI 1000-3000 (group II). Ninety percent of the patients with pre-transplant anti-HLA antibodies had class I antibodies, while only seven patients developed class II. Patients in group III were less likely to receive transplants than patients without any anti-HLA antibodies (group I) (45.5% vs. 67.7%; p=0.005). Wait time to transplant was longer in group III than group I, though this difference did not meet statistical significance, and waitlist mortality was similar. Among transplant recipients, antibody mediated rejection (AMR) was more frequent in group III than in group II (20% vs. 0%, p=0.01) or group I (6.3%, p=0.05). Conclusion: The presence of anti-HLA antibodies at the high MFI threshold (>3000) was associated with lower transplant rate and higher rates of AMR. Screening for anti-HLA antibodies using the 3000 MFI threshold may be important in managing transplant candidates and recipients.
    Preview · Article · Apr 2014 · American Journal of Respiratory and Critical Care Medicine
  • Sara Rostas · Miae Kim · Steven Gabardi
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    ABSTRACT: Objective: To review risks associated with mycophenolic acid (MPA) preparations and evaluate their required risk evaluation and mitigation strategies (REMS) elements. Data sources and extraction: Articles were identified through a non-date-limited MEDLINE and EMBASE search using the terms fetal toxicity, teratogenicity, risk evaluation and mitigation strategies, REMS, MPA, mycophenolate mofetil, entericcoated MPA, and organ transplant. Information from the Food and Drug Administration (FDA) and the manufacturers of the MPA preparations was also evaluated. Data synthesis: The MPA preparations are associated with several potential risks, including gastrointestinal disturbances and myelosuppression; however, their impact on the fetus in pregnant patients taking 1 of these agents poses the greatest risk. The FDA approved REMS programs for all MPA products, both innovator and generic preparations, in September 2012. With evidence of increased risk of miscarriage and birth defects associated with MPA use, the FDA instituted a REMS program that contains both a medication guide and elements to assure safe use (ETASU). Conclusion: The medication guides for the MPA products, which were previously FDA approved, should continue to be distributed to patients who get either an initial prescription filled or a refill. The ETASU requires prescribers to complete training and obtain patient signatures on the Patient-Prescriber Acknowledgment Form. A single, national, voluntary pregnancy registry specific to this medication has been established, and pregnant patients should be encouraged to participate. Although the impact of the MPA REMS on clinical practice is not clear, it is a step toward increasing the understanding of fetal risks with MPA.
    No preview · Article · Mar 2014 · Progress in transplantation (Aliso Viejo, Calif.)
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    ABSTRACT: Background: More than 30% of potential kidney transplant recipients have pre-existing anti-human leukocyte antigen antibodies. This subgroup has significantly lower transplant rates and increased mortality. Desensitization has become an important tool to overcome this immunological barrier. However, limited data is available regarding long-term outcomes, in particular for the highest risk group with a positive complement-dependent cytotoxicity crossmatch (CDC XM) before desensitization. Methods: Between 2002 and 2010, 39 patients underwent living-kidney transplantation across a positive CDC XM against their donors at our center. The desensitization protocol involved pretransplant immunosuppression, plasmapheresis, and low-dose intravenous immunoglobulin±rituximab. Measured outcomes included patient survival, graft survival, renal function, rates of rejection, infection, and malignancy. Results: The mean and median follow-up was 5.2 years. Patient survival was 95% at 1 year, 95% at 3 years, and 86% at 5 years. Death-censored graft survival was 94% at 1 year, 88% at 3 years, and 84% at 5 years. Uncensored graft survival was 87% at 1 year, 79% at 3 years, and 72% at 5 years. Twenty-four subjects (61%) developed acute antibody-mediated rejection of the allograft and one patient lost her graft because of hyperacute rejection. Infectious complications included pneumonia (17%), BK nephropathy (10%), and CMV disease (5%). Skin cancer was the most prevalent malignancy in 10% of patients. There were no cases of lymphoproliferative disorder. Mean serum creatinine was 1.7±1 mg/dL in functioning grafts at 5 years after transplantation. Conclusion: Despite high rates of early rejection, desensitization in living-kidney transplantation results in acceptable 5-year patient and graft survival rates.
    No preview · Article · Feb 2014 · Transplantation
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    ABSTRACT: De novo thrombotic microangiopathy (TMA) following renal transplantation is a severe complication associated with high rates of allograft failure. Several immunosuppressive agents are associated with TMA. Conventional approaches to managing this entity, such as withdrawal of the offending agent and/or plasmapheresis, often offer limited help, with high rates of treatment failure and graft loss. We herein report a case of drug induced de novo TMA successfully treated using the C5a inhibitor culizumab in a renal transplant patient. This report highlights a potentially important role for eculizumab in settings where druginduced de novo TMA is refractory to conventional therapies.
    No preview · Article · Feb 2014 · Clinical nephrology
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    ABSTRACT: Use of rituximab, a chimeric monoclonal antibody directed at the CD20 antigen, continues to increase in solid organ transplantation (SOT) for several off-label uses. In September 2013, the United States Food and Drug Administration (FDA) issued a Drug Safety Communication to oncology, rheumatology and pharmacy communities outlining a new Boxed Warning for rituximab. Citing 109 cases of fatal hepatitis B virus (HBV) reactivation in persons receiving rituximab therapy with previous or chronic HBV infection documented in their Adverse Event Reporting System (AERS), the FDA recommends screening for HBV serologies in all patients planned to receive rituximab and antiviral prophylaxis in any patient with a positive history of HBV infection. There is a lack of data pertaining to this topic in the SOT population despite an increase in off-label indications. Previous reports suggest patients receiving rituximab, on average, were administered six doses prior to HBV reactivation. Recommendations on prophylaxis, treatment and re-challenging patients with therapy after resolution of reactivation remain unclear. Based on data from the FDA AERS and multiple analyses in oncology, SOT providers utilizing rituximab should adhere to the FDA warnings and recommendations regarding HBV reactivation until further data are available in the SOT population.
    Preview · Article · Feb 2014 · American Journal of Transplantation
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    ABSTRACT: BK virus reactivation in kidney transplant recipients can lead to progressive allograft injury. Reduction of immunosuppression remains the cornerstone of treatment for active BK infection. Fluoroquinolone antibiotics are known to have in vitro antiviral properties, but the evidence for their use in patients with BK viremia is inconclusive. The objective of the study was to determine the efficacy of levofloxacin in the treatment of BK viremia. Enrollment in this prospective, multicenter, double-blinded, placebo-controlled trial occurred from July 2009 to March 2012. Thirty-nine kidney transplant recipients with BK viremia were randomly assigned to receive levofloxacin, 500 mg daily, or placebo for 30 days. Immunosuppression in all patients was adjusted on the basis of standard clinical practices at each institution. Plasma BK viral load and serum creatinine were measured monthly for 3 months and at 6 months. At the 3-month follow-up, the percentage reductions in BK viral load were 70.3% and 69.1% in the levofloxacin group and the placebo group, respectively (P=0.93). The percentage reductions in BK viral load were also equivalent at 1 month (58% versus and 67.1%; P=0.47) and 6 months (82.1% versus 90.5%; P=0.38). Linear regression analysis of serum creatinine versus time showed no difference in allograft function between the two study groups during the follow-up period. A 30-day course of levofloxacin does not significantly improve BK viral load reduction or allograft function when used in addition to overall reduction of immunosuppression.
    Preview · Article · Jan 2014 · Clinical Journal of the American Society of Nephrology
  • Steven Gabardi

    No preview · Article · Sep 2013 · Journal of Pharmacy Practice and Research
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    S L Aitken · H R Palmer · J E Topal · S Gabardi · E Tichy

    Full-text · Article · Jul 2013 · American Journal of Transplantation
  • S Gabardi · K Townsend · S.T. Martin · A Chandraker
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    ABSTRACT: Background: A correlation exists between polyomavirus BK (BKV) viremia in renal transplant recipients (RTR) and the degree of immunosuppression. However, the impact of pre-transplant desensitization on the incidence of BKV viremia is unknown. Methods: This retrospective study evaluated living-donor RTR between January 2004 and December 2008 receiving routine BKV viral load monitoring. Patients were divided into those who underwent pre-transplant desensitization (n = 20) and those who did not (n = 71). The primary endpoint was the incidence of BKV viremia at 1 year post transplant. Results: All demographic data were similar, except for more female patients (65% vs. 36.6%; P = 0.0392) in the desensitized group. More desensitized patients had a previous transplant (75% vs. 12.7%; P < 0.0001) and were more likely to be induced with basiliximab (75% vs. 35.2%; P = 0.0021). Following transplantation, antibody-mediated rejection (AMR) rates were highest in the desensitized group (55% vs. 1.4%; P < 0.0001). The incidence of BKV viremia at 1 year post transplant was significantly higher in desensitized patients (45% vs. 19.7%; P = 0.0385). Desensitization was also associated with a higher prevalence of BKV viremia at any time post transplant (50% vs. 22.5%; P = 0.0245), polyomavirus-associated nephropathy (20% vs. 2.8%; P = 0.0198) and BKV-related allograft loss (10% vs. 0%; P = 0.0464). Also of note, in a subgroup analysis of only our desensitized patients, it did not appear that development of AMR significantly impacted the incidence of BKV viremia in these individuals. Conclusions: This analysis reveals that pre-transplant desensitization significantly increases the risk for BKV viremia and nephropathy.
    No preview · Article · May 2013 · Transplant Infectious Disease
  • M Kim · S Rostas · S Gabardi
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    ABSTRACT: The mycophenolic acid (MPA) preparations are one of the most commonly used immunosuppressants in the United States. However, these agents carry a black box warning regarding their use during pregnancy due to an association with increased risk of miscarriage and congenital defects. To ensure that the benefits of MPA outweigh the risks, the Food and Drug Administration (FDA) required all manufacturers of MPA products to propose risk evaluation and mitigation strategies (REMS). Four years after initially calling for proposals, the FDA approved a single shared REMS system in September 2012. The elements of the MPA REMS include a medication guide and elements to assure safe use (ETASU). The medication guide, which was previously FDA-approved in 2008, should continue to be distributed to patients, and the ETASU requires physicians to complete training and obtain patient signatures on the "Patient-Prescriber Acknowledgement Form." A single, national, voluntary pregnancy registry is available, and pregnant patients should be encouraged to participate. Although the impact of the MPA REMS on clinical practice is not clear, it is a step toward increasing the understanding of fetal risks with MPA products among patients and possibly practitioners.
    No preview · Article · Apr 2013 · American Journal of Transplantation

  • No preview · Conference Paper · Apr 2013

  • No preview · Conference Paper · Apr 2013

Publication Stats

944 Citations
180.74 Total Impact Points

Institutions

  • 2010-2015
    • Harvard University
      Cambridge, Massachusetts, United States
  • 2007-2015
    • Harvard Medical School
      • Department of Medicine
      Boston, Massachusetts, United States
  • 2004-2015
    • Brigham and Women's Hospital
      • • Department of Pharmacy
      • • Center for Brain Mind Medicine
      Boston, Massachusetts, United States
  • 2002-2004
    • Northeastern University
      • Department of Pharmacy Practice
      Boston, Massachusetts, United States