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M S Shaefer

Publications and source records attributed to M S Shaefer.

At least 19 recordsLinked to original sources
PubMed2006

A prospective, 96-week study of the impact of Trizivir, Combivir/nelfinavir, and lamivudine/stavudine/nelfinavir on lipids, metabolic parameters and efficacy in antiretroviral-naive patients: effect of sex and ethnicity.

OBJECTIVES: To compare the lipid and metabolic effects, efficacy, and safety of twice-daily regimens of Trizivir (abacavir 300 mg/lamivudine 150 mg/zidovudine 300 mg triple nucleoside tablet; TZV), Combivir (lamivudine 150 mg/zidovudine 300 mg combination tablet; COM)+nelfinavir (NFV), and stavudine (d4 T)+lamivudine (3TC)+NFV. STUDY DESIGN: An international, phase 4, open-label, parallel-group, 34-centre study was conducted in 254 non-diabetic, antiretroviral-naive, HIV-infected out-patients with an HIV-1 RNA level of >1000 HIV-1 RNA copies/mL and < or =200,000 copies/mL and a CD4 cell count of >50 cells/microL. METHODS: Patients were randomized 1 : 1 : 1 to TZV twice daily (n = 85), COM/NFV 1250 mg twice daily (n = 88), or d4T 40 mg+3TC 150 mg+NFV 1250 mg twice daily (n = 81) for 96 weeks. Treatments were compared using analysis of covariance (ANCOVA) with regard to changes from baseline in fasting lipids in the total population and in sex and ethnic subgroups. The proportions of patients achieving HIV-1 RNA <50 and <400 copies/mL were compared using a 95% confidence interval (CI) on the difference between proportions. RESULTS: The study population was diverse (50% female, 40% black and 37% Hispanic). Mean baseline low-density lipoprotein (LDL) cholesterol was 99 mg/dL, HIV-1 RNA was 4.43 log10 copies/mL and CD4 cell count was 355 cells/microL. At week 96, fasting LDL cholesterol changed minimally in the TZV group [least square mean (LSM) change from baseline, -8 mg/dL], but increased with d4T/3TC/NFV and COM/NFV (+29 and +19 mg/dL, respectively; P < 0.001 versus TZV). Week 96 LDL-cholesterol levels were significantly lower in the TZV group than in the other two treatment groups in women and men and lower than in the d4T/3TC/NFV group in Hispanic and black patients. In black patients, the week-96 LSM change from baseline in LDL cholesterol was significantly less with TZV than with d4T/3TC/NFV (+1 vs+39 mg/dL; P = 0.003). Total cholesterol >200 mg/dL occurred in a smaller proportion of patients receiving TZV (30%) compared with COM/NFV (50%) or d4T/3TC/NFV (60%; P = 0.005 vs TZV). High-density lipoprotein (HDL) cholesterol did not change markedly with any treatment. Although triglycerides increased, they changed least in women and Hispanic patients receiving TZV. Virological and CD4 responses to the treatments were similar in the total population and in the subgroups. Diarrhoea was reported more often in the NFV arms and nausea in the ZDV arms. CONCLUSIONS: Over 96 weeks, TZV twice daily has significantly less effect on LDL cholesterol than COM/NFV or d4T/3TC/NFV twice daily, especially in women and black patients, and is associated with similar virological and CD4 responses.

Black or African American↗
PubMed2001

Twice-daily triple nucleoside intensification treatment with lamivudine-zidovudine plus abacavir sustains suppression of human immunodeficiency virus type 1: results of the TARGET Study.

This open-label, multicenter, single-arm clinical trial assessed the 48-week efficacy of a twice-daily triple nucleoside reverse-transcriptase inhibitor regimen containing a lamivudine (150 mg)-zidovudine (300 mg) combination tablet (COM) and abacavir (ABC; 300 mg) in 87 antiretroviral therapy-experienced, protease inhibitor-naive patients infected with human immunodeficiency virus type 1 (HIV-1). At baseline, the median plasma HIV-1 RNA level was 3.10 log(10) copies/mL, and the median CD4 cell count was 506 cells/mm(3). An intent-to-treat&rcolon;observed analysis showed that, at weeks 24 and 48 of treatment, HIV-1 RNA level was <400 copies/mL in 48 (76%) of 63 and 45 (82%) of 55 patients, respectively, and <50 copies/mL in 37 (59%) of 63 and 31 (56%) of 55 patients, respectively. Previous zidovudine or lamivudine use and presence at baseline of the M184V reverse-transcriptase mutation did not impact virologic response. Median CD4 cell counts were maintained above baseline throughout the study. COM plus ABC was generally well tolerated.

Adult↗
PubMed2000

Efficacy, safety, and adherence with a twice-daily combination lamivudine/zidovudine tablet formulation, plus a protease inhibitor, in HIV infection.

OBJECTIVE: A randomized, open-label, multicenter study to establish clinical equivalence (non-inferiority) of a regimen employing a lamivudine 150 mg/zidovudine 300 mg combination tablet, administered twice daily, plus a marketed protease inhibitor, compared with a conventional regimen of 150 mg lamivudine twice daily, 600 mg zidovudine daily, and a protease inhibitor, in antiretroviral-experienced patients infected with HIV-1. PATIENTS: Adults who were seropositive for HIV-1 infection with plasma HIV-1 RNA levels < 10000 copies/ml (Roche Amplicor polymerase chain reaction assay, lower limit of quantitation (LLOQ) 400 copies/ml) and CD4+ cell counts > or = 300 x 10(6)/l). All patients had been receiving the conventional lamivudine/zidovudine/protease inhibitor regimen for > or = 10 weeks immediately prior to the study. INTERVENTION: Patients were randomized to the conventional regimen (n = 113) or combination tablet regimen (n = 110) for 16 weeks. The primary study endpoint was treatment failure, defined as an increase in HIV-1 RNA > or = 0.5 log10 above baseline in patients with viral load > LLOQ at randomization and as HIV-1 RNA increasing to > or = 1250 copies/ml in patients with viral load < LLOQ at randomization. RESULTS: The combination tablet regimen was associated with a 3.5% greater success rate than the conventional regimen (96.4 versus 92.9%), with four and eight patients failing treatment due to increases in HIV-1 RNA levels, respectively. The lower limit of the associated confidence interval for the difference was -2.4%, which was well within the -10% margin predefined as clinically unimportant. This establishes the clinical equivalence (non-inferiority) of the combination tablet regimen to the conventional regimens regarding virologic response. The combination tablet and conventional regimens were similar with respect to percentage of patients maintaining HIV-1 RNA levels < LLOQ at the end of study or improving from baseline to undetectability (94 versus 91%; P= 0.063), overall incidence of drug-related adverse events (21 versus 19%) (P=0.868), and mean area under the curve for CD4+ cell counts [treatment difference, 5.9 cells (95% confidence interval, -15.8 to 27.6 x 10(6) cells/l)]. A self-reported adherence questionnaire indicated that patients in the combination tablet group were less likely to miss doses of nucleoside analogue medication at weeks 8 (P= 0.007) and 16 (P= 0.046). CONCLUSIONS: The combination lamivudine/zidovudine tablet/protease inhibitor regimen is clinically equivalent (non-inferior) to the conventional regimen with respect to virologic response and may offer adherence advantages.

Adult↗
PubMed1995

Pharmacokinetics of tacrolimus in liver transplant patients.

OBJECTIVE: To characterize the pharmacokinetics of the immunosuppressive agent tacrolimus (FK 506) in liver transplant patients. METHODS: Patients (n = 16) were assessed during and after 1- to 3-day intravenous infusions followed by a 2-week course of oral dose therapy. Plasma and whole blood data were fitted simultaneously with equations accounting for nonlinear drug binding by red blood cells to generate clearance (CL) and volume of distribution (V). RESULTS: The maximum blood/plasma ratio of tacrolimus was 55.5 +/- 26.8 (SD) and half-life averaged 12.1 +/- 4.7 hours. The CL and V were relatively high based on plasma concentrations (CL, 1.7 L/hr/kg; V, 30 L/kg) and low based on whole blood (CL, 54 ml/hr/kg; V, 0.9 L/kg), with moderate variability (coefficient of variation, 34% to 49%) among the patients. Correlations of plasma CL and V with maximum blood/plasma ratios (ranging from 13 to 114) were strong (r = 0.65 and r = 0.73). Blood binding affects the disposition of tacrolimus, and plasma concentrations are indirectly and inversely related to red cell binding. The oral dose data for tacrolimus yielded a brief absorption lag time (tlag, 0.39 hour), a variable first-order absorption rate constant (ka, 4.5 +/- 3.0 hr-1), and consistent bioavailability (F, 25% +/- 10%). The area under the concentration-time curve versus 12-hour minimum concentration relationships for both whole blood and plasma were nearly linear, confirming the utility of trough values for monitoring drug exposure. CONCLUSION: This study provides pharmacokinetic guidelines for the use of tacrolimus in patients undergoing hepatic transplantation. Nonlinear blood binding is a major source of interpatient variation in the disposition of tacrolimus.

Administration, Oral↗
PubMed1995

Evaluation of the pharmacokinetic interaction between cimetidine or famotidine and cyclosporine in healthy men.

OBJECTIVE: To investigate the potential interaction between cimetidine or famotidine and cyclosporine in healthy men. DESIGN: All subjects received oral cyclosporine at baseline, after the first week of 1 histamine2 (H2)-blocker, and a third time after a 1-week washout plus 1 week of the second H2-blocker. Blood samples were collected just before each dose of cyclosporine and for up to 36 hours afterward for pharmacokinetic analysis. SETTING: A college of pharmacy in a university teaching hospital. PARTICIPANTS: The study population consisted of 8 healthy men at least 19 years of age. MAIN OUTCOME MEASURES: Cyclosporine concentrations in whole blood were measured using a polyclonal fluorescence polarization immunoassay. Cyclosporine pharmacokinetic parameters during each of the 3 treatment periods were compared. RESULTS: The average times to maximum cyclosporine concentrations were similar between baseline (3.2 h), cimetidine (2.9 h), and famotidine (3.6 h) dosing periods. There were no significant differences in area under the curve, half-life, or maximum concentration during the 3 dosing periods. CONCLUSIONS: Neither cimetidine or famotidine produced a significant change in the pharmacokinetics of single-dose oral cyclosporine in healthy men.

Adult↗
PubMed1993

Blind comparison of patient preference for Flavored Colestid Granules and Questran Light.

OBJECTIVE: To compare the sensory and mixability characteristics of Flavored Colestid Granules (a new colestipol formulation) with Questran Light (the most recent cholestyramine formulation). METHODOLOGY: Seventy-two nonsmoking adults between the ages of 25 and 64 years were enrolled in the study. Subjects assessed the sensory and mixability characteristics of each product in chilled bottled water and orange juice after at least a one-hour fast. Products were administered in a double-blind, randomized fashion. The sensory characteristics that were rated included overall rating, aftertaste, appearance, aroma, color, consistency, flavor, sweetness, mouthfeel, and thickness. Each characteristic was rated with a nine-point hedonic scale. Mixability of the products was assessed on a five-point scale. Subjects also were asked to choose which product they preferred as to sensory and mixability characteristics in each vehicle. RESULTS: Fifty-three of the 72 subjects preferred the sensory characteristics of Flavored Colestid Granules in water (p < 0.001). Questran Light was preferred by 61 subjects when mixed in orange juice (p < 0.001). The sensory characteristic rating scores also supported subject preferences for Flavored Colestid Granules in water and Questran Light in orange juice. Mixability of Flavored Colestid Granules was rated significantly better (p < 0.001) than Questran Light in water. There was no significant difference for mixability between the products in orange juice. CONCLUSIONS: Questran Light was significantly preferred on a sensory basis when mixed in orange juice. Flavored Colestid Granules was significantly preferred over Questran Light for both sensory and mixability characteristics with water as the vehicle.

Adult↗
PubMed1993

Successful application of extracorporeal liver perfusion: a technology whose time has come.

We have used extracorporeal liver perfusion (ECLP) to aid in the management of three patients with fulminant hepatic failure (FHF). Organs were used for ECLP only if they would have gone otherwise unused through United Network for Organ Sharing. In all three patients treated, serial serum bilirubin and arterial ammonia values trended toward the normal range. The neurologic examinations improved dramatically in two patients, and metabolic function of the extracorporeally perfused livers was unequivocally demonstrated by the clearance of theophylline in the last two patients. Two patients ultimately had successful liver transplants, whereas the third patient failed to improve neurologically despite evidence of metabolic function by the extracorporeally perfused liver, and died 7 days after ECLP was discontinued, from pulmonary and renal failure. These studies suggest that, 30 yr after initial clinical trials, ECLP can be applied safely without the need for arterial access 1) as a bridge to transplantation, 2) to assess whether patients in FHF will benefit from improved hepatic function and therefore transplantation, and 3) potentially, to evaluate the "usability" of questionable donor organs.

Adolescent↗
PubMed1992

A randomized prospective trial of acyclovir and immune globulin prophylaxis in liver transplant recipients receiving OKT3 therapy.

The use of OKT3 therapy is a major risk factor for opportunistic infections in liver transplant recipients. In the last 2 years, we prospectively randomized 100 patients receiving OKT3 therapy into either a control group (n = 50) or a prophylaxis group (n = 50). Prophylaxis consisted of six doses of intravenous immune globulin over 4 weeks and oral acyclovir for 3 months after OKT3 therapy. The two groups were comparable with respect to demographic, immunologic, and clinical characteristics. The regimen of prophylaxis resulted in (1) a significant reduction in the incidence of herpetic and Epstein-Barr viral infections; (2) no change in the incidence of cytomegalovirus infections; (3) a significant decrease in the incidence of fungal infections; and (4) fewer deaths due to sepsis. The incidence of viral and fungal infections was higher after OKT3 induction than after rescue therapy. Our conclusion is that opportunistic infections are frequent after OKT3 therapy in hepatic allograft recipients. Treatment with intravenous immune globulin and oral acyclovir is safe and effective in preventing non-cytomegaloviral and fungal infections in this setting, thus conferring a survival advantage with fewer deaths due to sepsis.

Acyclovir↗
PubMed1992

Treatment of valproic acid-associated hepatic failure with orthotopic liver transplantation.

OBJECTIVE: To report a case of valproic acid (VPA)-induced hepatotoxicity and to discuss the incidence rates, risk factors, possible etiologies, preventive measures, and treatment courses for this severe reaction. DATA SOURCES: Case reports, review articles, and relevant laboratory studies identified by MEDLINE. DATA EXTRACTION: Data were abstracted from pertinent published sources by one author and reviewed by the remaining authors. DATA SYNTHESIS: The case of a 23-year-old woman with VPA-associated hepatic failure was successfully treated with orthotopic liver transplantation. Hepatic failure is a rare, often fatal, adverse effect of VPA. Most cases of VPA-associated hepatic failure have occurred within several months of initiation of therapy. Initial symptoms of presentation often include nausea and vomiting, lethargy, or loss of seizure control. Laboratory values to be monitored include serum concentrations of hepatic enzymes, and, in some patients, tests indicative of the liver's synthetic capabilities. The exact mechanism of VPA-associated hepatic failure has not been clearly established; however, it is postulated to involve the formation of toxic metabolites. Major risk factors include age less than two years and concomitant treatment with more than one anticonvulsant. Other significant risk factors include underlying metabolic or serious neurologic disorders. CONCLUSIONS: Caution should be taken when initiating VPA therapy and clinicians should be familiar with the risk factors and clinical presentation of this reaction.

Adult↗
PubMed1992

Histologic changes in liver allograft biopsies associated with elevated whole blood and tissue cyclosporine concentrations.

Cyclosporine is used in the postoperative management of rejection in liver allograft recipients. Despite its efficacy in the treatment of allograft rejection, the drug exhibits toxicity at elevated whole blood concentrations including nephrotoxicity with associated histologic changes, and evidence of hepatotoxicity as determined by liver function studies. To date, there have been few published reports describing histologic changes in liver biopsies from patients with elevated blood cyclosporine levels. In the present study, we retrospectively examined biopsies from 16 liver allograft recipients, seven patients with elevated whole blood cyclosporine levels (> 1000 ng/ml) and nine control patients who had whole blood cyclosporine levels in the therapeutic range (558 to 993 ng/ml). In each case, frozen liver biopsy tissue was available to measure tissue levels of cyclosporine and metabolites. The blood and tissue drug levels were then correlated with the histologic changes present in the biopsy specimens. Patients with increased cyclosporine levels displayed histologic changes consisting of hypertrophy of the bile ductal epithelium with cytoplasmic vacuoles and the presence of "foamy" material within the hepatic sinusoids that were either absent or occurred less frequently in the control group. The histologic changes correlated best with cyclosporine metabolite levels rather than tissue levels of native drug. When liver function studies were correlated with cyclosporine levels, only gamma glutamyl transpeptidase (GGT) demonstrated a significant positive correlation with the histologic changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1991

Clinical spectrum of fungal infections after orthotopic liver transplantation.

During a 50-month period, we identified 91 episodes of fungal infection in 72 liver transplant recipients (23.8%). Candida species accounted for 83.5% of cases. Clinical patterns of fungal infections included disseminated infection (19), peritonitis (17), pneumonitis (15), multiple sites of colonization (13), fungemia (11), and other sites (16). The diagnosis of fungal infection was usually made in the first 2 months (84.7% of cases), at a mean time of 16 days after transplantation. Risk factors for fungal infections included retransplantation, Risk score, intraoperative transfusion requirement, urgent status, Roux limb biliary reconstruction (in adults), steroid dose, bacterial infections and antibiotic therapy, and vascular complications. Fungal infections were successfully treated with amphotericin B in 63 cases (74.1%) but were associated with diminished patient survival (50% vs 83.5%). Fungal infection is a frequent source of early morbidity and can be related to well-defined risk factors, suggesting the need for effective prophylaxis.

Adolescent↗
PubMed1991

Successful prophylaxis of cytomegalovirus disease after primary CMV exposure in liver transplant recipients.

UNLABELLED: During a 38-month period, we studied 320 liver transplants in 283 recipients (202 adults, 81 children). CMV disease was documented in 85 patients (30.0%) The major risk factor for CMV disease was primary CMV exposure (transplanting a seropositive allograft into a seronegative recipient). A total of 42 patients (14.8%) had primary CMV exposure. Twenty-one patients were historical controls, while the next 21 received prophylaxis for CMV infection in a nonrandomized trial of consecutive study groups. The regimen of prophylaxis consisted of intravenous immune globulin (IgG; 0.5 g/kg) at weekly intervals for 6 weeks and acyclovir for 3 months. CMV prophylaxis resulted in a dramatic reduction in the incidence of CMV disease (71.4% vs. 23.8%, (P less than 0.01). All cases of CMV were treated with intravenous ganciclovir (5 mg/kg b.i.d. for 14 days), with 5 patients in the control group developing recurrent CMV disease (33.3% relapse). In the 16 patients receiving prophylaxis who did not develop CMV disease, all developed positive CMV-IgG titers with the passive administration of IgG. However, none developed any evidence of CMV infection or viral shedding as assessed by IgM titers and surveillance viral cultures. Four deaths occurred (all control patients), but none were related to CMV disease. Overall patient and graft survivals after primary CMV exposure were 90.5% and 82.2%, respectively, after a mean follow-up of 14 months. CONCLUSION: Primary CMV exposure is a major risk factor for CMV disease in liver transplant recipients. Intravenous IgG plus acyclovir is safe and effective in preventing CMV infection and disease in this setting. Because of the scarcity of donor organs, we do not advocate protective matching to avoid primary CMV exposure but rather recommend prophylaxis to prevent CMV disease in this high-risk group.

Acyclovir↗
PubMed1991

Current topics in immunotherapy and the role of the pharmacist on a solid organ transplant service.

Solid organ transplantation has become a well-accepted therapy for the treatment of end-stage disease of the liver, heart, kidney, and pancreas. The development of highly effective immunosuppressant drugs has led to major improvements in graft and patient survival over the last decade. In spite of this success the perfect immunosuppressive drug has yet to be discovered. Currently available agents have numerous short-term and, more disturbingly, long-term toxicities. This has led to the use of triple- and quadruple-drug regimens in an attempt to maintain good graft and patient survival rates with less toxicity. Multiple-drug combinations have questionable benefits compared to double-drug regimens containing cyclosporine and prednisone. With the advent of new immunosuppressant drugs, it will be important to perform randomized, controlled trials to assess their efficacy and toxicities in comparison with current regimens. Pharmacists who work with solid organ transplant teams can function as pharmacotherapists and provide skills such as pharmacokinetic and pharmacodynamic drug monitoring. In addition, they can become involved with clinical and laboratory-based research to assess the properties of conventional and newly developed immunosuppressive agents.

Cyclosporine↗
PubMed1990

Drug-induced hypertrichosis: case report and review of the literature.

Hypertrichosis is a well-recognized adverse effect of therapy with either cyclosporine or minoxidil. We present a case of extreme hypertrichosis in an eight-year-old male liver transplant recipient who received concurrent cyclosporine and minoxidil therapy. A review of drug-induced hypertrichosis is presented.

Child↗