Steady-state pharmacokinetics of lamivudine in human immunodeficiency virus-infected patients with end-stage renal disease receiving chronic dialysis

Steady-state pharmacokinetics of lamivudine in end-stage kidney failure persons with detectable and undetectable HIV-1 RNA in peritoneal dialysis effluent

BACKGROUND

Renally adjusted lamivudine dosages are effective. However, some of the kidney failure patients managed with lamivudine-containing regimens are failing to suppress HIV in peritoneal dialysis (CAPD) effluent. The steady-state lamivudine pharmacokinetics among these patients was evaluated.

METHODS

This overnight open-label pharmacokinetic study enrolled participants living with HIV and managed with CAPD. Lamivudine levels in blood serum and CAPD effluent samples were quantified using liquid chromatography coupled with a mass spectrometer. Pharmacokinetic measures were obtained through non-compartmental analysis.

RESULTS

Twenty-eight participants were recruited with a median antiretroviral (ARV) drug duration of 8 (IQR,4.5-10.5) years and a CAPD duration of 13.3 (IQR,3.3-31.9) months. 14.3% (4/28) had detectable unsuppressed HIV-1 viral load in CAPD effluents. The majority (78,6%,22/28) of participants received a 50 mg dose, while 10.7% (3/28), and another 10.7% (3/28) received 75 mg and 300 mg dosages, respectively. Among those treated with 75 and 300 mg, 66.7% (2/3) and 33.3% (1/3) had detectable HIV-VL in CAPD, respectively. The peritoneal membrane characteristics and CAPD system strengths were variable across the entire study population. Lamivudine exposure was increased in blood serum (50 mg-AUC0-24 h, 651.3 ng/mL; 75 mg-AUC0-24 h, 677.84 ng/mL; 300 mg-AUC0-24 h, 3135.89 ng/mL) compared to CAPD effluents (50 mg-AUC0-24 h, 384.91 ng/mL; 75 mg-AUC0-24 h, 383.24 ng/mL; 300 mg-AUC0-24 h, 2001.60 ng/mL) among the entire study population. The Cmax (50 mg, 41.5 ng/mL; 75 mg, 53.2 ng/mL; 300 mg, 199.1 ng/mL) and Cmin (50 mg, 17.8 ng/mL; 75 mg, 16.4 ng/mL; 300 mg, 76.4 ng/mL) measured in serum were within the therapeutic levels.

CONCLUSIONS

Steady-state lamivudine pharmacokinetic measures were variable among the entire study population. However, the total lamivudine exposure was within the therapeutic levels.

Antiretrovirals for People with HIV on Dialysis

In the era of widespread use of antiretroviral therapy (ART), people with HIV (PWH) have a near-normal life expectancy. However, PWH have high rates of kidney diseases and progression to end-stage renal disease at a younger age. PWH have multiple risks for developing acute and chronic kidney diseases, including traditional risk factors such as diabetes, hypertension, and HIV-related factors such as HIV-associated nephropathy and increased susceptibility to infections and exposure to nephrotoxic medications. Despite an improvement in access to kidney transplant among PWH, the number of PWH on dialysis continues to increase. The expansion of the number of antiretrovirals (ARVs) and kidney replacement modalities, the absence of pharmacokinetic data, and therapeutic drug monitoring make it very challenging for providers to dose ARVs appropriately leading to medication errors, adverse events, and higher mortality. Most of the recommendations are either based on small sample size studies or extrapolated based on physiochemical characteristics of ART. We aim to review the most available and most current literature on ART in PWH with renal insufficiency and ART dosing recommendations on dialysis to ensure that PWH are provided with the safest and most effective ART regimen.

Lactic acidosis and hyperlactatemia associated with lamivudine accumulation and sepsis in a kidney transplant recipient-a case report and review of the literature

Background

We report a case of sudden, lethal metabolic acidosis in a 70-year-old man on long-term nucleoside reverse transcriptase inhibitor (NRTI) -based antiretroviral therapy (ART) who had developed atypical necrotizing fasciitis 1 month after kidney transplantation.

Case presentation

The HIV infection of the patient was treated for the last four months with an integrase strand inhibitor (dolutegravir 50 mg/d) plus a NRTI backbone including lamivudine (150 mg/d) and abacavir (600 mg/d). In this renal transplant patient we hypothesize that the co-existence of sepsis, renal failure and an accumulation of lamivudine led to the development of fatal metabolic acidosis and hyperlactatemia. Although lamivudine is only rarely associated with hyperlactatemia, there is evidence that overdose may be a risk factor for developing it. In our patient the lamivudine concentration two days after stopping and during hemodiafiltration was more than 50 times higher than therapeutic target trough concentrations. Likely reasons for this were renal impairment and concurrent treatment with trimethoprim, known to inhibit the renal elimination of lamivudine.

Conclusions

NRTIs could trigger the development of hyperlactatemia in septic patients. The use of NRTI sparing regimens might be considered in the presence of this critical condition.

A retrospective evaluation of highly active antiretroviral therapy simplification in patients with end-stage renal disease receiving hemodialysis

Antiretroviral (ARV) therapy in people living with HIV (PLWH) and end-stage renal disease (ESRD) on hemodialysis (HD) is complicated, requiring renally adjusted nucleoside reverse transcriptase inhibitors (NRTIs) and daily administration of non-renally eliminated agents. Recent data in PLWH with ESRD on HD demonstrate maintenance of viral suppression (82% with viral loads (VLs) <50 copies/mL) and favorable safety/tolerability profiles after ARV simplification with a fixed dose combination single tablet [elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF)]. Extrapolation of these data to all F/TAF formulations would allow ARV simplification to most PLWH with ESRD receiving HD. The objective of this retrospective study was to identify if ARV-experienced PLWH with ESRD on HD receiving renally adjusted NRTIs may be simplified to once daily ARV formulations without adverse effects while maintaining viral suppression. This single-center retrospective analysis assessed virologic control (3-12 months) and ARV tolerability post-regimen simplification (primarily NRTI once-daily dose adjustment) in PLWH with ESRD on thrice weekly HD receiving human immunodeficiency virus (HIV) care in an ambulatory clinic. Seventeen PLWH with ESRD on HD were included after documented ARV simplification. At 12 months, 12 patients (71%) remained undetectable (HIV VL <50 copies/mL) with two additional maintaining viral suppression (<200 copies/mL). One patient remained undetectable at month eight but became non-adherent with viral rebound. Two patients did not complete the 6- and 12-month evaluation after documented nonadherence (N = 1) and an adverse effect (pruritus) (N = 1). At 12 months, virologic suppression and tolerability resulted after a simplified ARV regimen including once daily F/TAF was initiated in PLWH with ESRD on thrice weekly HD with a reduction in pill burden.

Initial Antiretroviral Therapy in an Integrase Inhibitor Era: Can We Do Better?

With the second-generation integrase inhibitors (dolutegravir and bictegravir) extending the attributes of earlier integrase inhibitors, three-drug regimens containing integrase inhibitors plus two nucleos(t)ide reverse transcriptase inhibitors are now widely recommended for first-line (initial) treatment of human immunodeficiency virus-1 infection. Led by dolutegravir plus lamivudine, two-drug therapy is emerging as a way to reduce antiretroviral therapy cost and adverse effects without compromising treatment options should virologic failure occur. Initial two-drug therapy has limitations, including the relative incompatibility with the coemerging concept of same-day antiretroviral therapy initiation.

Abacavir/lamivudine/dolutegravir single tablet regimen in patients with human immunodeficiency virus and end-stage renal disease on hemodialysis

No single-tablet antiretroviral (ARV) regimens (STRs) are approved for patients with human immunodeficiency virus (HIV) and end-stage renal disease (ESRD) on hemodialysis (HD). Based on known pharmacokinetic (PK) properties, abacavir (ABC)/lamivudine (3TC)/dolutegravir (DTG) STR may represent a promising option. This case series presents the safety and efficacy of ABC/3TC/DTG STR in patients with HIV and ESRD on HD. Patients were included if they were HIV-positive, maintained on intermittent HD for ESRD, switched to an ARV regimen containing ABC/3TC/DTG, and had at least one set of virologic data before and after the switch. Average age (±standard deviation) was 59 (±8) years. The majority of patients were cis-gender male and non-Hispanic Black. Only one demonstrated clinically significant resistance at baseline. All were on multiple-tablet regimens prior to the switch. Five patients (83%) achieved undetectable HIV-RNA after the switch while only four patients (46%) were undetectable immediately prior. No decline in immune function was noted. ABC/3TC/DTG STR was well tolerated. Only one patient self-reported an adverse event (nausea), which resolved without drug discontinuation. Based on these data, it appears that ABC/3TC/DTG may be a safe and effective ARV-STR option for patients with HIV and ESRD on HD. A larger trial including a PK analysis is needed to confirm these findings.

Real-World Experience With Higher-Than-Recommended Doses of Lamivudine in Patients With Varying Degrees of Renal Impairment

Background

Although nucleoside reverse transcriptase inhibitors have been associated with lactic acidosis, lamivudine (3TC) has not been reported to have an increased risk with elevated concentrations. Therefore, some recommend that the lowest tablet strength of 3TC be considered in patients with kidney disease to avoid the inconvenience of liquid formations. Our institution avoids dose-adjusting 3TC until creatinine clearance (CrCl) <30 mL/min and uses 100–150-mg tablets daily in hemodialysis. The aim of this study was to describe the use of higher-than-recommended doses of 3TC in a real-world setting.

Methods

Blood samples were collected before and 0.5–1.5 hours after 3TC administration in HIV+ adults. Predose (C_min) and postdose (C_max) samples were measured by high-performance liquid chromatography. Physiologically based pharmacokinetic modeling was utilized to simulate areas under the curve (AUCs) and profiles by CrCl. Lactic acid levels and patient-reported adverse events were obtained to monitor for safety, and viral suppression was assessed for efficacy.

Results

Thirty-four patients with varying degrees of renal function were enrolled. Observed 3TC C_max values were comparable among CrCl cohorts. Simulated 3TC AUC values in patients with CrCl 30–49, 15–29, and 0–15 mL/min were consistent with historical data, and fold-errors were between 0.5 and 2.0. All lactic acid levels were within normal limits, and no adverse effects were reported.

Conclusions

This study is the first to describe the use of higher-than-recommended doses of 3TC in a real-world setting. 3TC was well tolerated across all levels of renal function. These results can guide providers in their selection of higher 3TC dosing in select patients with renal dysfunction to maximize adherence.

Detection of human immunodeficiency virus-1 ribonucleic acid in the peritoneal effluent of renal failure patients on highly active antiretroviral therapy

Background

We evaluated the shedding of human immunodeficiency virus (HIV)-1 particles into continuous ambulatory peritoneal dialysis (CAPD) effluents of HIV-positive patients with end-stage renal disease (ESRD).

Methods

A total of 58 HIV-positive patients with ESRD on highly active antiretroviral therapy (HAART) who had Tenckhoff catheters inserted between September 2012 and February 2015 were prospectively reviewed and followed for 18 months. Peritoneal dialysis (PD) effluent samples from functioning CAPD catheters and plasma samples were obtained at three points during regular clinic visits on days 45 ± 37, 200 ± 19 and 377 ± 13 after catheter insertion. All specimens were stored at -20°C, and each batch was analysed by Roche quantitative HIV-1 polymerase chain reaction assay to detect HIV-1 particles. Clustered logistic regression was used to test for independent predictors of HIV-1 detection in CAPD effluents.

Results

HIV-1 RNA above 20 copies/mL assay limit was detectable in 19% (first batch), 26.3% (second batch) and 20% (third batch) of PD effluent specimens. HIV-1 RNA was detectable in PD fluid, without corresponding detection in the paired plasma in 3.4% (first batch), 5.3% (second batch) and 10% (third batch) of samples. Detection of HIV-1 in plasma sample (odds ratios 3.94; 95% confidence interval 1.14-13.55; P = 0.030), body mass index, serum albumin and HAART regimen were found to be significantly associated with HIV-1 detection in PD effluents.

Conclusions

HIV particles are shed in detectable amounts into CAPD effluents even in patients with suppressed plasma viral load, raising concerns of a localized sanctuary site and potential infectivity of HIV-positive CAPD patients on a full complement of HAART.

Clinical practice guideline for the management of chronic kidney disease in patients infected with HIV: 2014 update by the HIV Medicine Association of the Infectious Diseases Society of America

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Biowaiver monographs for immediate release solid oral dosage forms: lamivudine

Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing lamivudine as the only active pharmaceutical ingredient were reviewed. The solubility and permeability data of lamivudine as well as its therapeutic index, its pharmacokinetic properties, data indicating excipient interactions, and reported BE/bioavailability (BA) studies were taken into consideration. Lamivudine is highly soluble, but its permeability characteristics are not well-defined. Reported BA values in adults ranged from 82% to 88%. Therefore, lamivudine is assigned to the biopharmaceutics classification system (BCS) class III, noting that its permeability characteristics are near the border of BCS class I. Lamivudine is not a narrow therapeutic index drug. Provided that (a) the test product contains only excipients present in lamivudine IR solid oral drug products approved in the International Conference on Harmonization or associated countries in usual amounts and (b) the test product as well as the comparator product fulfills the BCS dissolution criteria for very rapidly dissolving; a biowaiver can be recommended for new lamivudine multisource IR products and major post-approval changes of marketed drug products.

Steady-state pharmacokinetics of lamivudine once-daily versus twice-daily dosing in Chinese HIV-infected patients

OBJECTIVE

The present study aimed to compare the pharmacokinetics of lamivudine in 300 mg once-daily and 150 mg twice-daily dosing regimens in HIV-infected Chinese patients.

METHODS

HIV-infected patients received lamivudine 300 mg once daily or 150 mg twice daily as part of a highly active antiretroviral therapy regimen. After the patients received lamivudine for at least 3 months, serial blood samples were collected for 24 hours. The samples were measured by a validated high-performance liquid chromatography (HPLC) assay. The pharmacokinetics of once-daily versus twice-daily dosing was evaluated by noncompartment models.

RESULTS

Ten patients received lamivudine 300 mg once daily and 5 patients received 150 mg twice daily. The C(max) was significantly higher in the once-daily arm than the twice-daily arm (2.23 vs 1.61 μg/mL, P <.05), whereas the C(min) was markedly lower (0.05 vs 0.12 μg/mL, P <.05). The half-lives were 3.32 hours and 2.62 hours, and AUC₂₄ values were 11.8 μg/mL·h and 13.0 μg/mL·h in the 300 mg once-daily and 150 mg twice-daily regimens, respectively (P >.05).

CONCLUSION

The shorter half-life was observed first in Chinese HIV patients with once- and twice-daily regimens. The 300 mg once-daily regimen was associated with lower trough concentrations and remarkable interpatient variability. Further studies in large groups of HIV patients are needed to confirm the influence of shorter half-lives in Chinese patients on efficacy and toxicity.

Nephrotoxicity associated with antiretroviral therapy in HIV-infected patients

BACKGROUND

With the success of modern antiretroviral therapies in increasing longevity of patients with HIV infection, chronic conditions including renal disease have assumed a greater importance in patient management. Some antiretroviral therapies have themselves been identified to have clinically significant nephrotoxicity.

OBJECTIVE

To review the risk factors and mechanisms for renal toxicity of antiretroviral drugs, and their impact on the clinical management of patients with HIV.

METHODS

Current literature and HIV treatment guidelines are reviewed.

RESULTS/CONCLUSIONS

Background rates of renal disease and associated risk factors are significant in the HIV clinic population, and renal function should be assessed in all HIV-infected patients. Modern HIV treatment regimens have a relatively low but clinically significant nephrotoxic potential; therefore, renal function should be evaluated on an ongoing basis in patients receiving antiretroviral therapy.

Pharmacology, clinical efficacy and safety of lamivudine in hepatitis B virus infection

Lamivudine was the first nucleoside analog for the treatment of chronic hepatitis B (CHB). It is well-tolerated and induces a decrease in serum HBV DNA levels associated with normalization of serum alanine aminotransferase levels. However, a sustained response with hepatitis B 'e' antigen to anti-hepatitis B e seroconversion is obtained in a smaller proportion of patients and hepatitis B surface antigen loss is exceptional. The response is maintained during therapy, and needs to be continued indefinitely in the majority of patients since withdrawal of treatment is generally followed by a rapid reappearance of the virus. However, mutations can be induced in long-term treatment.

Hepatitis B virus infection in dialysis patients

Hepatitis B virus (HBV) infection remains a major issue among dialysis patients. It is associated with a high risk of hepatic complication. The liver disease runs a unique clinical course in dialysis patients, as it can progress with modest hepatic inflammation and prominent fibrosis. The conventional cut-off level of serum alanine aminotransferase (ALT) for commencing antiviral therapy may prove too high and inappropriate for dialysis patients, and liver biopsy appears to be the only definitive means to establish the activity of liver disease in dialysis patients. Liver biopsy should be considered in patients with a serum ALT level that is persistently greater than 30 IU/L, or 0.75-fold the upper limit of the normal level, and/or other clinical and laboratory findings that suggest active liver disease. For antiviral treatment, preliminary reports have shown that lamivudine is effective and well tolerated in dialysis patients. However, the long-term efficacy of lamivudine and its optimal effective dose in dialysis patients remain unknown. The prevention of nosocomial transmission among dialysis patients is also important. Universal precaution measures should be strictly observed and the segregation of hepatitis B surface antigen-positive hemodialysis patients should be considered. For HBV non-immune patients, the importance of HBV vaccination should not be overemphasized. Until a new generation of highly immunogenic vaccines that are proven to be safe and effective in patients with end-stage renal disease becomes available, early vaccination before the development of end-stage renal failure remains the best way to secure immunological protection against HBV infection in dialysis patients.

Use of highly active antiretroviral therapy in patients with renal insufficiency

Antiretroviral agents, especially nucleoside reverse transcriptase inhibitors, require significant dosage adjustments in patients who have renal dysfunction and the human immunodeficiency virus (HIV). Some antiretroviral agents and fixed combination preparations are contraindicated in this population. In addition, many preferred antiretroviral regimens may be difficult to administer conveniently in patients with decreased creatinine clearance or in those receiving renal replacement therapies. Some highly active antiretroviral therapy regimens, however, can be used conveniently in patients with HIV and altered renal function.

Pharmacology considerations for antiretroviral therapy in human immunodeficiency virus (HIV)-infected children

The contemporary treatment of the child infected with human immunodeficiency virus (HIV) unavoidably requires combination therapy with antiretroviral agents and may include additional drugs for the prevention and treatment of opportunistic infections or other disease states. The current guidelines for the treatment of the HIV-infected child recommend that the same principles of treatment for adults should apply to children. However, the pharmacokinetic and pharmacodynamic characteristics of many agents and regimens used in adults have not been defined adequately in children, and large-scale clinical trials to establish safety and show efficacy have not been completed. Therefore, the clinician will be required to use agents with incomplete knowledge about their pharmacologic properties. The purpose of this article is to provide an overview of the pediatric pharmacologic principles, a review of the pharmacologic characteristics of selected antiretroviral agents in children, and a prospectus on the design of drug dosing regimens in children.

The clinical characteristics and antiretroviral dosing patterns of HIV-infected patients receiving dialysis

BACKGROUND

Human immunodeficiency virus (HIV)-related renal disease is the third leading cause of end-stage renal disease (ESRD) among African Americans aged 24 to 60 years. This study describes the clinical characteristics and antiretroviral dosing patterns of HIV-infected patients receiving dialysis to define the clinical needs of this growing population.

METHODS

Demographic and clinical information was collected on all HIV-infected patients incident to dialysis after January 1, 1998 until January 1, 2001 at five medical centers. The cohort was described overall and by subgroups based on hepatitis status, CD4 lymphocyte count, and use of antiretroviral therapy. Continuous and categoric variables were compared using either the Wilcoxon rank sum or Student t test and Fisher's exact or chi-square tests, as appropriate.

RESULTS

A total of 89 patients were included, 55 of whom were alive at the time of data collection. The mean age was 44.6 years (range, 22.7 to 66.9 years), 74.2% were male, and 83.2% patients were African Americans. While only 45.9% of patients undergoing renal biopsy were diagnosed with HIV-associated nephropathy (HIVAN), the majority of patients who had not undergone biopsy carried the clinical diagnosis of HIVAN (69.8%, P = 0.03). Of the cohort, 19.7% tested hepatitis B surface antigen positive, and 67.1% had reactive antibody tests for hepatitis C. Patients with hepatitis C were more likely to have experienced intravenous drug use as a risk behavior for HIV acquisition (OR 8.2; 95% CI 2.39, 27.9; P = 0.001] and to be older (OR 1.1 per year of age; 95% CI 1.02, 1.2; P = 0.01). A total of 60.7% of patients were receiving antiretroviral medication at last follow-up. Among patients alive and receiving antiretroviral medications at the time of data collection, absolute CD4+ count rose (268 vs. 339 cells/mL, P = 0.03), while among patients alive, but not receiving antiretroviral medications, absolute CD4+ count did not change (389 vs. 392 cells/mL, P = 0.11) during similar periods of follow-up. No difference was seen between initial and current HIV RNA levels for either group. Among patients receiving antiretroviral medications, there were significant variations in dosing regimens. The greatest variation was seen in the prescribing patterns of lamivudine with a 12-fold difference among patients.

CONCLUSION

The projected growth of the HIV-infected ESRD population requires a better understanding of the clinical needs of this population. The high prevalence of coinfection with hepatitis C as well as the wide variations in dosing patterns for antiretroviral medications are areas that require further investigation to minimize morbidity and mortality among this group.