The ASSURE study: HIV-1 suppression is maintained with bone and renal biomarker improvement 48 weeks after ritonavir discontinuation and randomized switch to abacavir/lamivudine + atazanavir.

OBJECTIVES: HIV treatment guidelines endorse switching or simplification of antiretroviral therapy in therapy-experienced patients with suppressed viraemia; ritonavir discontinuation may also enhance tolerability and reduce long-term adverse events (AEs). This open-label, multicentre, noninferiority study enrolled HIV-1-infected, treatment-experienced adults with confirmed HIV-1 RNA ≤ 75 HIV-1 RNA copies/mL currently receiving tenofovir/emtricitabine + atazanavir/ritonavir (TDF/FTC + ATV/r) for ≥ 6 months with no reported history of virological failure. METHODS: Participants were randomized 1:2 to continue current treatment or switch to abacavir/lamivudine + atazanavir (ABC/3TC + ATV). Endpoints included the proportion of participants with HIV-1 RNA < 50 copies/mL by time to loss of virological response (TLOVR), AEs, fasting lipids, and inflammatory, coagulation, bone and renal biomarkers. RESULTS: After 48 weeks, 76% (152 of 199) of ABC/3TC + ATV-treated and 79% (77 of 97) of TDF/FTC + ATV/r-treated participants had HIV-1 RNA < 50 copies/mL (TLOVR; P = 0.564). Other efficacy analyses yielded similar results. Rates of new grade 2-4 AEs were 45% in both groups, but an excess of hyperbilirubinaemia made the rate of treatment-emergent grade 3-4 laboratory abnormalities higher with TDF/FTC + ATV/r (36%) compared with ABC/3TC + ATV (19%). Most fasting lipid levels remained stable over time; high-density lipoprotein (HDL) cholesterol increased modestly in ABC/3TC + ATV-treated participants. Bone and renal biomarkers improved significantly between baseline and week 48 in participants taking ABC/3TC + ATV and were stable in participants taking TDF/FTC + ATV/r. No significant changes occurred in any inflammatory or coagulation biomarker within or between treatment groups. CONCLUSIONS: The ABC/3TC + ATV treatment-switch group had similar viral suppression rates up to 48 weeks to the TDF/FTC + ATV/r comparator group, with lower rates of moderate- to high-grade hyperbilirubinaemia and improvements in bone and renal biomarkers.

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.

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.

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.

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.

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.

Clinical patterns of cytomegalovirus disease after liver transplantation.

During a 43-month period, we performed 248 liver transplantations in 211 patients (127 adults and 84 children). Cytomegalovirus (CMV) disease was documented in 73 recipients (34.6%). Risk factors for CMV disease included donor CMV seropositivity, antilymphocyte therapy, and retransplantation. The mean time of occurrence of CMV disease was 38.3 days after transplantation, and the most frequent site of disease was the hepatic allograft. A total of 69 patients were treated with intravenous ganciclovir, with a prompt and lasting response documented in 51 (73.9%). The remaining 18 (26.1%) developed recurrent CMV disease, which was more common after primary CMV exposure. Cytomegalovirus disease was ultimately controlled by ganciclovir in 94.2% of cases. This disease occurs early after transplantation and can be related to well-defined risk factors. Although ganciclovir therapy is effective, preliminary experience with prophylaxis shows promise in reducing the incidence of CMV disease.

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.

Prolonged paralysis associated with long-term pancuronium use.

We cared for a 4-year-old patient who had undergone orthotopic liver transplantation and was placed on a ventilator for respiratory distress associated with Pneumocystis carinii pneumonia. The neuromuscular blocking agent pancuronium bromide 1.0-1.2 mg every hour as needed was used to facilitate artificial ventilation for 40 days. On discontinuation of pancuronium, the patient experienced severe, generalized neuromuscular dysfunction. Because no improvement was seen for 2 weeks, the acetylcholinesterase inhibitors edrophonium and pyridostigmine were instituted. Shortly thereafter the patient's condition began to improve. Gradual improvement occurred over 3-4 months and the patient has since returned to baseline neurologic function. We suggest that long-term pancuronium use was the cause of the patient's prolonged paralysis. The improvement experienced after the initiation of antidotal therapy strongly supports our proposal.

Hepatic failure associated with imipramine therapy.

Imipramine, a widely used antidepressant, has rarely been associated with hepatic abnormalities. In the majority of reported cases, hepatic effects have been transient and readily reversible on discontinuation of the drug. We cared for an 11-year-old boy with hepatic failure and massive cell necrosis which followed treatment with imipramine for enuresis. This therapy led to fulminant hepatic failure and subsequent liver transplantation.

Correlation between self-reported adherence to highly active antiretroviral therapy (HAART) and virologic outcome.

The Patient Medication Adherence Questionnaire Version 1.0 (PMAQ-V1.0) is a patient-reported adherence instrument to assess medication-taking behaviors and identify barriers to adherence with antiretroviral therapy. To assess the correlation between adherence and virologic outcome, the PMAQ-V1.0 was administered to 194 antiretroviral-experienced adults with HIV infection enrolled in a 16-week evaluation of protease inhibitor-containing regimens featuring a lamivudine/zidovudine combination tablet. At baseline, plasma HIV-1 RNA levels were less than 10,000 copies/mL and CD4(+)-cell counts were equal to or greater than 300 x 10(6)/L; patients had been receiving a conventional regimen of lamivudine + zidovudine (separately) plus a protease inhibitor for at least 10 weeks immediately prior to the study. Forty-eight percent of patients who reported missing at least one dose of a nucleoside reverse-transcriptase inhibitor (NRTI) during the study had detectable plasma HIV-1 RNA, compared with 26% of patients who reported no missed doses (P = .002). Patients who missed at least one dose of an NRTI or protease inhibitor were 2.5 times more likely to have quantifiable HIV-1 RNA than those who reported no missed doses. Patients who reported fewer barriers and more motivators to adherence had better virologic outcomes (P = .001). Several dimensions of the PMAQ-V1.0 did not function as well as hypothesized. In this study, self-reported adherence derived from the PMAQ-V1.0 predicted virologic outcomes, but further refinement of the dimensions appears warranted.

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.

Acceptability of cholestyramine or colestipol combinations with six vehicles.

Preferences for cholestyramine or colestipol in combination with orange drink, orange juice, grape juice, apple juice, water, or apple sauce were evaluated in 40 healthy adults. Each subject evaluated the taste, texture, and smell of 30-mL samples of 12 drug-vehicle combinations (two drugs, six vehicles) using modified five-point wine-tasting scales. Samples were prepared to contain either cholestyramine 1.0 g or colestipol hydrochloride 1.3 g. The products were tested at room temperature and were administered in a random order. Subjects and observers were blinded to the identity of the products. Acceptability scores for taste, texture, and smell were significantly higher for cholestyramine than for colestipol. Total mean preference scores for cholestyramine-vehicle combinations ranged from 9.9 to 11.7; for colestipol, 6.3 to 8.9. Orange drink, apple juice, grape juice, and orange juice were the preferred vehicles for cholestyramine. The preferred vehicles for colestipol were orange drink, apple sauce, and apple juice.

Idiopathic thromboembolism associated with triphasic oral contraceptives.

Oral contraceptives are one of the most effective and widely used of the reversible contraceptive methods. Thromboembolic disease associated with the use of oral contraceptives has been widely reported. In recent years, attempts to understand the pathogenesis of oral contraceptive-induced thromboembolic disease have found a correlation between larger estrogen doses and increased risk for a thrombotic event. Because the newer triphasic oral contraceptives provide effective contraception with a method of administration that mimics normal hormonal fluctuations during the menstrual cycle, some prescribers may infer that these products are associated with a decreased incidence of adverse effects over alternative oral contraceptives. We present two cases of idiopathic thromboembolism associated with the use of a triphasic oral contraceptive with a discussion of the proposed pathogenic mechanisms for these events.

PIP: 2 cases of thromboembolism in young women with no risk factors except use of triphasic oral contraceptives are reported. A 21-year old White woman, Gravida I Para I, presented to the emergency room with a painful, blue, mottled right lower leg after pain in the hip and buttock for 1 week. She had taken a triphasic oral contraceptive containing 35 mcg ethinyl estradiol and 0.5, 0.75, 1 mg norethindrone for 1 month, and had no other related history. Doppler and venogram tests showed thrombosis of the ileal, femoral, popliteal and infrapopliteal veins. She was treated with heparin, streptokinase, and urokinase without success and recovered after ileal, femoral and popliteal thrombectomy. The 2nd case was a 30-year-old Gravida III Para I Black woman who had taken a pill containing 50 mcg ethinyl estradiol and 500 mcg norgestrel for 13 years and had recently switched to the triphasic pill described above. She had dull midepigastric pain, nausea, vomiting, diarrhea and chills, for 1 week. Physical exam was negative except for abdominal tenderness and a heart murmur. Abdominal ultrasound revealed portal venous thrombosis extending to the splenic and superior mesenteric veins. She was treated with transhepatic urokinase without effect and celiotomy was performed. She was discharged with an occluded right branch of the portal vein. These cases point out the fact that the estrogen dose in triphasic pills is not lower than that in low dose combined oral contraceptives.