Pharmacokinetic Model of Tenofovir and Emtricitabine and Their Intracellular Metabolites in Patients in the ANRS 134-COPHAR 3 Trial Using Dose Records.

Tenofovir (TFV) and emtricitabine (FTC) are part of the recommended highly active antiretroviral therapy (ART). Both molecules show a large interindividual pharmacokinetic (PK) variability. Here, we modeled the concentrations of plasma TFV and FTC and their intracellular metabolites (TFV diphosphate [TFV-DP] and FTC triphosphate [FTC-TP]) collected after 4 and 24 weeks of treatment in 34 patients from the ANRS 134-COPHAR 3 trial. These patients received daily (QD) atazanavir (300 mg), ritonavir (100 mg), and a fixed-dose combination of coformulated TFV disoproxil fumarate (300 mg) and FTC (200 mg). Dosing history was collected using a medication event monitoring system. A three-compartment model with absorption delay (Tlag) was selected to describe the PK of, respectively, TFV/TFV-DP and FTC/FTC-TP. TFV and FTC apparent clearances, 114 L/h (relative standard error [RSE] = 8%) and 18.1 L/h (RSE = 5%), respectively, were found to decrease with age. However, no significant association was found with the polymorphisms ABCC2 rs717620, ABCC4 rs1751034, and ABCB1 rs1045642. The model allows prediction of TFV-DP and FTC-TP concentrations at steady state with alternative regimens.

Cerebrospinal fluid exposure to bictegravir/emtricitabine/tenofovir in HIV-1-infected patients with CNS impairment.

OBJECTIVES: The penetration of antiretroviral drugs into deep compartments, such as the CNS, is a crucial component of strategies towards an HIV cure. This study aimed to determine CSF concentrations of bictegravir, emtricitabine and tenofovir in patients with HIV-related CNS impairment (HCI) enrolled in a real-life observational study. METHODS: Patients with HCI treated by optimized ART, including bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) for at least 1 month were enrolled. Plasma and CSF concentrations were measured by quality control-validated assays (LC-MS/MS). The inhibitory quotient (IQARV) was calculated as the ratio of unbound (bictegravir) or total (emtricitabine and tenofovir) concentration to half (or 90%) maximal inhibitory concentration for bictegravir (or emtricitabine and tenofovir). All numerical variables are expressed as median (range). RESULTS: Twenty-four patients (nine women) were enrolled. The age was 45 (26-68) years. Unbound bictegravir and total emtricitabine and tenofovir CSF concentrations were 4.4 (1.6-9.6), 84.4 (28.6-337.4) and 1.6 (0.7-4.3) ng/mL, respectively. The unbound bictegravir CSF fraction was 34% (15%-82%) versus 0.33% (0.11%-0.92%) in plasma. Three patients had an IQARV above unity for the three antiretrovirals. Factors positively associated with the CSF concentration (unbound for bictegravir) were age and total plasma concentration for the three antiretrovirals. Patients aged over 51 years had higher CSF concentrations (unbound for bictegravir). CONCLUSIONS: We observed low CSF exposure to bictegravir, emtricitabine and tenofovir. These results suggest that BIC/FTC/TAF should be used with caution as first-line treatment for people living with HIV with HCI under 51 years of age.

Characteristics of Dolutegravir and Bictegravir Plasma Protein Binding: a First Approach for the Study of Pharmacologic Sanctuaries.

This study aimed to characterize in vitro dolutegravir (DTG) and bictegravir (BIC) binding. They had a preferential binding to human serum albumin (HSA) with two classes of albumin sites. Human alpha-1-acid glycoprotein (HAAG) binding of DTG and BIC showed an atypical nonlinear binding. The low-affinity site on HSA, the main plasma binding protein, suggests that the high protein binding rate should not impair passive diffusion.

Effect of high-dose rifampicin on efavirenz pharmacokinetics: drug-drug interaction randomized trial.

BACKGROUND: High-dose rifampicin is considered to shorten anti-TB treatment duration but its effect on antiretroviral metabolism is unknown. OBJECTIVES: To assess the effect of doubling the rifampicin dose (to 20 mg/kg/day, R20) on efavirenz pharmacokinetics (PK) in HIV/TB coinfected patients. METHODS: Open-label Phase 2 drug-drug interaction randomized trial. Pulmonary TB, ART-naive adults were randomized to R20 and either efavirenz 600 mg (EFV600) or 800 mg (EFV800), or rifampicin 10 mg/kg/day (R10) and EFV600 with a 1:1:1 ratio. Patients were first started on TB treatment and 2-4 weeks later started on ART. They were switched to R10 and EFV600 after 8 weeks. Full PK sampling was done 4 weeks (on rifampicin) and 24 weeks (off rifampicin) after ART initiation. Transaminases, plasma HIV-1 RNA and sputum cultures were monitored. The efavirenz geometric mean ratio (GMR) of AUC at 4 and 24 weeks after ART initiation within the same patient was calculated in each arm and its 90% CI was compared with a preset range (0.70-1.43). RESULTS: Of 98 enrolled patients (32 in the R20EFV600 arm, 33 in the R20EFV800 arm and 33 in the R10EFV600 arm), 87 had full PK sampling. For the R20EFV600, R20EFV800 and R10EFV600 arms, GMRs of efavirenz AUC were 0.87 (90% CI: 0.75-1.00), 1.12 (90% CI: 0.96-1.30) and 0.96 (90% CI: 0.84-1.10). Twelve weeks after ART initiation, 78.6%, 77.4% and 72.4% of patients had HIV-1 RNA below 100 copies/mL and 85.7%, 86.7% and 80.0% had Week 8 culture conversion, respectively. Two patients per arm experienced a severe increase in transaminases. CONCLUSIONS: Doubling the rifampicin dose had a small effect on efavirenz concentrations and was well tolerated.

Comparison of the effect of direct-acting antiviral with and without ribavirin on cyclosporine and tacrolimus clearance values: results from the ANRS CO23 CUPILT cohort.

PURPOSE: Direct-acting antiviral agents have demonstrated their efficacy in treating HCV recurrence after liver transplantation and particularly the sofosbuvir/daclatasvir combination. Pharmacokinetic data on both calcineurin inhibitors and direct-acting antiviral exposure in liver transplant recipients remain sparse. METHODS: Patients were enrolled from the ANRS CO23 CUPILT cohort. All patients treated with sofosbuvir/daclatasvir with or without ribavirin were included in this study when blood samples were available to estimate the clearance of immunosuppressive therapy before direct-acting antiviral initiation and during follow-up. Apparent tacrolimus and cyclosporine clearances were estimated from trough concentrations measured using validated quality control assays. RESULTS: Sixty-seven mainly male patients (79%) were included, with a mean age of 57 years and mean MELD score of 8.2; 50 were on tacrolimus, 17 on cyclosporine. Ribavirin was combined with sofosbuvir/daclatasvir in 52% of patients. Cyclosporine clearance remained unchanged as well as tacrolimus clearance under the ribavirin-free regimen. Tacrolimus clearance increased 4 weeks after direct-acting antivirals and ribavirin initiation versus baseline (geometric mean ratio 1.81; 90% CI 1.30-2.52). Patients under ribavirin had a significantly higher fibrosis stage (> 2) (p = 0.02) and lower haemoglobin during direct-acting antiviral treatment (p = 0.02) which impacted tacrolimus measurements. Direct-acting antiviral exposure was within the expected range. CONCLUSION: Our study demonstrated that liver transplant patients with a recurrence of hepatitis C who are initiating ribavirin combined with a sofosbuvir-daclatasvir direct-acting antiviral regimen may be at risk of lower tacrolimus concentrations because of probable ribavirin-induced anaemia and higher fibrosis score, although there are no effects on cyclosporine levels. TRIAL REGISTRATION: NCT01944527.

Dolutegravir Cerebrospinal Fluid Diffusion in HIV-1-Infected Patients with Central Nervous System Impairment.

This study aimed to determine dolutegravir cerebrospinal fluid (CSF) diffusion in 13 patients with HIV-related cerebral impairment enrolled in a real-life observational study. Dolutegravir median (range) CSF concentration [9.6 (3.6-22.8) ng/mL] reached CSF therapeutic concentrations whatever the blood-brain barrier status and diffused in correlation with the albumin quotient (P = .0186).

Cholic acid for primary bile acid synthesis defects: a life-saving therapy allowing a favorable outcome in adulthood.

BACKGROUND: Oral cholic acid (CA) replacement has been shown to be an effective therapy in children with primary bile acid synthesis defects, which are rare and severe genetic liver diseases. To date there has been no report of the effects of this therapy in children reaching adulthood. The aim of the study was to evaluate the long-term effectiveness and safety of CA therapy. METHODS: Fifteen patients with either 3ß-hydroxy-Δ5-C27-steroid oxidoreductase (3ß-HSD) (n = 13) or Δ4-3-oxosteroid 5ß-reductase (Δ4-3-oxo-R) (n = 2) deficiency confirmed by mass spectrometry and gene sequencing received oral CA and were followed prospectively. RESULTS: The median age at last follow-up and the median time of follow-up with treatment were 24.3 years (range: 15.3-37.2) and 21.4 years (range: 14.6-24.1), respectively. At last evaluation, physical examination findings and blood laboratory test results were normal in all patients. Liver sonograms were normal in most patients. Mean daily CA dose was 6.9 mg/kg of body weight. Mass spectrometry analysis of urine showed that excretion of the atypical metabolites remained low or traces in amount with CA therapy. Liver fibrosis scored in liver biopsies or assessed by elastography in 14 patients, after 10 to 24 years with CA therapy, showed a marked improvement with disappearance of cirrhosis (median score < F1; range: F0-F2). CA was well tolerated in all patients, including five women having 10 uneventful pregnancies during treatment. CONCLUSIONS: Oral CA therapy is a safe and effective long-term treatment of 3ß-HSD and Δ4-3-oxo-R deficiencies and allows affected children to reach adulthood in good health condition without the need for a liver transplantation.

Pharmacokinetics of efavirenz in patients on antituberculosis treatment in high human immunodeficiency virus and tuberculosis burden countries: A systematic review.

AIMS: Efavirenz (EFV) and rifampicin-isoniazid (RH) are cornerstone drugs in human immunodeficiency virus (HIV)-tuberculosis (TB) coinfection treatment but with complex drug interactions, efficacy and safety challenges. We reviewed recent data on EFV and RH interaction in TB/HIV high-burden countries. METHODS: We conducted a systematic review of studies conducted in the high TB/HIV-burden countries between 1990 and 2016 on EFV pharmacokinetics during RH coadministration in coinfected patients. Two reviewers conducted article screening and data collection. RESULTS: Of 119 records retrieved, 22 were included (two conducted in children), reporting either EFV mid-dose or pre-dose concentrations. In 19 studies, median or mean concentrations of RH range between 1000 and 4000 ng ml-1 , the so-called therapeutic range. The proportion of patients with subtherapeutic concentration of RH ranged between 3.1 and 72.2%, in 12 studies including one conducted in children. The proportion of patients with supratherapeutic concentration ranged from 19.6 to 48.0% in six adult studies and one child study. Five of eight studies reported virological suppression >80%. The association between any grade hepatic and central nervous system adverse effects with EFV/RH interaction was demonstrated in two and three studies, respectively. The frequency of the CYP2B6 516G > T polymorphism ranged from 10 to 28% and was associated with higher plasma EFV concentrations, irrespective of ethnicity. CONCLUSIONS: Anti-TB drug coadministration minimally affect the EFV exposure, efficacy and safety among TB-HIV coinfected African and Asian patients. This supports the current 600 mg EFV dosing when coadministered with anti-TB drugs.

Sofosbuvir-Based Regimens in HIV/HCV Coinfected Patients After Liver Transplantation: Results From the ANRS CO23 CUPILT Study.

BACKGROUND: A recurrence of hepatitis C virus (HCV) after liver transplantation affects survival in human immunodeficiency virus (HIV)/HCV coinfected patients. This study assessed the efficacy and safety of sofosbuvir (SOF)-based regimens in HIV/HCV coinfected patients after liver transplantation. METHODS: Twenty-nine HIV/HCV coinfected transplanted patients receiving tacrolimus-, cyclosporine-, or everolimus-based immunosuppressive therapy were enrolled in the Compassionate Use of Protease Inhibitors in Viral C Liver Transplantation cohort. Their antiviral treatment combined SOF, daclatasvir with or without ribavirin (n = 10/n = 6), or SOF, ledipasvir with or without ribavirin (n = 2/n = 11). RESULTS: The median delay between liver transplantation and treatment initiation was 37.5 months (interquartile range [IQR], 14.4-99.2). The breakdown of HCV genotypes was G1, 22 patients (75.9%); G3, 3 patients (10.3%); and G4, 4 patients (13.8%). The treatment indications were HCV recurrence (≥ F1 n = 23) or fibrosing cholestatic hepatitis (n = 6). Before starting SOF, the HCV viral load and CD4 count were 6.7 log10 IU/mL (IQR, 5.9-7.2) and 342 cells/mm (IQR, 172-483), respectively. At week 4, the HCV viral load was less than 15 IU/mL in 12 (42.9%) patients. The overall sustained virological response 12 was 96.6%. No significant drug-drug interactions were observed. CONCLUSIONS: SOF-based treatment regimens produced excellent results in HIV/HCV coinfected patients after liver transplantation, suggesting an important change in their prognosis.

Genetics of Nevirapine Metabolic Pathways at Steady State in HIV-Infected Cambodians.

Nevirapine is metabolized by several hepatic cytochrome P450 (CYP) isoforms to generate four primary hydroxylated metabolites: 2-hydroxynevirapine, 3-hydroxynevirapine, 8-hydroxynevirapine, and 12-hydroxynevirapine. The present study characterized associations between genetic polymorphisms and metabolite ratios in HIV-infected Cambodians. We demonstrate associations between CYP2B6 polymorphisms and metabolite ratios for both 3-hydroxynevirapine and 8-hydroxynevirapine, suggesting involvement of CYP2B6 in generating these metabolites.

Favipiravir pharmacokinetics in Ebola-Infected patients of the JIKI trial reveals concentrations lower than targeted.

BACKGROUND: In 2014-2015, we assessed favipiravir tolerance and efficacy in patients with Ebola virus (EBOV) disease (EVD) in Guinea (JIKI trial). Because the drug had never been used before for this indication and that high concentrations of the drugs were needed to achieve antiviral efficacy against EBOV, a pharmacokinetic model had been used to propose relevant dosing regimen. Here we report the favipiravir plasma concentrations that were achieved in participants in the JIKI trial and put them in perspective with the model-based targeted concentrations. METHODS AND FINDINGS: Pre-dose drug concentrations were collected at Day-2 and Day-4 of treatment in 66 patients of the JIKI trial and compared to those predicted by the model taking into account patient's individual characteristics. At Day-2, the observed concentrations were slightly lower than the model predictions adjusted for patient's characteristics (median value of 46.1 versus 54.3 µg/mL for observed and predicted concentrations, respectively, p = 0.012). However, the concentrations dropped at Day-4, which was not anticipated by the model (median values of 25.9 and 64.4 µg/mL for observed and predicted concentrations, respectively, p<10-6). There was no significant relationship between favipiravir concentrations and EBOV viral kinetics or mortality. CONCLUSIONS: Favipiravir plasma concentrations in the JIKI trial failed to achieve the target exposure defined before the trial. Furthermore, the drug concentration experienced an unanticipated drop between Day-2 and Day-4. The origin of this drop could be due to severe sepsis conditions and/or to intrinsic properties of favipiravir metabolism. Dose-ranging studies should be performed in healthy volunteers to assess the concentrations and the tolerance that could be achieved with high doses. TRIAL REGISTRATION: ClinicalTrials.gov NCT02329054.

Favipiravir Pharmacokinetics in Nonhuman Primates and Insights for Future Efficacy Studies of Hemorrhagic Fever Viruses.

Favipiravir is an RNA polymerase inhibitor that showed strong antiviral efficacy in vitro and in small-animal models of several viruses responsible for hemorrhagic fever (HF), including Ebola virus. The aim of this work was to characterize the complex pharmacokinetics of favipiravir in nonhuman primates (NHPs) in order to guide future efficacy studies of favipiravir in large-animal models. Four different studies were conducted in 30 uninfected cynomolgus macaques of Chinese (n = 17) or Mauritian (n = 13) origin treated with intravenous favipiravir for 7 to 14 days with maintenance doses of 60 to 180 mg/kg of body weight twice a day (BID). A pharmacokinetic model was developed to predict the plasma concentrations obtained with different dosing regimens, and the model predictions were compared to the 50% effective concentration (EC50) of favipiravir against several viruses. Favipiravir pharmacokinetics were described by a model accounting for concentration-dependent aldehyde oxidase inhibition. The enzyme-dependent elimination rate increased over time and was higher in NHPs of Mauritian origin than in those of Chinese origin. Maintenance doses of 100 and 120 mg/kg BID in Chinese and Mauritian NHPs, respectively, are predicted to achieve median trough plasma free concentrations above the EC50 for Lassa and Marburg viruses until day 7. For Ebola virus, higher doses are required. After day 7, a 20% dose increase is needed to compensate for the increase in drug clearance over time. These results will help rationalize the choice of dosing regimens in future studies evaluating the antiviral effect of favipiravir in NHPs and support its development against a variety of HF viruses.

Disseminated intravascular coagulation following administration of sunitinib.

Sunitinib is an increasingly used, orally administered targeted therapy, approved by the European Medicines Agency for the treatment of various types of cancer, including gastrointestinal stromal tumor unresectable or metastatic disease, following disease progression or intolerance to imatinib, and advanced or metastatic renal cell carcinoma, progressive well-differentiated pancreatic neuroendocrine tumors in patients with unresectable, locally advanced or metastatic disease. Sunitinib inhibits several tyrosine kinases, including the vascular endothelial growth factor receptor and the platelet-derived growth factor receptor. Tyrosine kinases inhibitor therapies are generally well-tolerated; nonetheless, they are not void of side effects. The majority of patients reported are grade 1 or 2, and include common and unspecific adverse events, including fatigue, gastrointestinal disorders, skin discoloration, altered taste, cough and dyspnea. Grade 3 or 4 adverse events, including bleeding and hemorrhage, are less frequent. The present study presented the first case of disseminated intravascular coagulation associated with the administration of sunitinib, shortly following the increase of sunitinib dosage.

Ebola Virus Infection: Review of the Pharmacokinetic and Pharmacodynamic Properties of Drugs Considered for Testing in Human Efficacy Trials.

The 2014-2015 outbreak of Ebola virus disease is the largest epidemic to date in terms of the number of cases, deaths, and affected areas. In October 2015, no antiviral agents had proven antiviral efficacy in patients. However, in September 2014, the World Health Organization inventoried and has since regularly updated a list of potential drug candidates with demonstrated antiviral efficacy in in vitro or animal models. This includes agents belonging to various therapeutic classes, namely direct antiviral agents (favipiravir and BCX4430), a combination of antibodies (ZMapp), type I interferons, RNA interference-based drugs (TKM-Ebola and AVI-7537), and anticoagulant drugs (rNAPc2). Here, we review the pharmacokinetic and pharmacodynamic information presently available for these drugs, using data obtained in healthy volunteers for pharmacokinetics and data obtained in human clinical trials or animal models for pharmacodynamics. Future studies evaluating these drugs in clinical trials are critical to confirm their efficacy in humans, propose appropriate doses, and evaluate the possibility of treatment combinations.

Raltegravir Pharmacokinetics in Patients on Asunaprevir-Daclatasvir.

Raltegravir pharmacokinetics was studied in 20 patients included in the ANRS HC30 QUADRIH Study before and after addition of anti-hepatitis C virus (anti-HCV) quadritherapy, including pegylated-interferon-ribavirin and asunaprevir plus daclatasvir. Raltegravir pharmacokinetic parameters remained unchanged whether administered on or off anti-HCV therapy. In addition, concentrations of raltegravir, asunaprevir, and daclatasvir were not affected by liver cirrhosis. These data suggest that in human immunodeficiency virus (HIV)-HCV-coinfected patients, whether cirrhotic or not, asunaprevir and daclatasvir could be administered safely with raltegravir.

Pharmacokinetics of Raltegravir in HIV-Infected Patients on Rifampicin-Based Antitubercular Therapy.

BACKGROUND: Rifampicin (RIF) induces UGT1A1, an enzyme involved in raltegravir (RAL) elimination, thereby potentially lowering RAL exposure. We examined the pharmacokinetics of RAL in human immunodeficiency virus (HIV)-infected patients on RIF-based antitubercular therapy in the French National Agency for HIV/AIDS and Viral Hepatitis Research 12 180 Reflate Tuberculosis trial. METHODS: Patients started RAL in combination with tenofovir disoproxil fumarate and lamivudine after initiation of RIF (10 mg/kg/day). In arm 1 (n = 21), they received 400 mg RAL twice daily; in arm 2 (n = 16), they received RAL 800 mg twice daily initially then 400 mg twice daily 4 weeks after RIF discontinuation. Pharmacokinetic sampling was performed over 12-hour periods, 4 weeks after initiation of RAL together with RIF (period 1), 4 weeks after RIF discontinuation (period 2), and after the RAL dose reduction in arm 2 (period 3). RESULTS: In arm 1, the geometric mean ratio (GMR) between period 1 and period 2 was 0.94 (90% confidence interval [CI], .64-1.37) for the 12-hour area under the time-concentration curve (AUC0-12), and 0.69 (90% CI, .42-1.13) for the concentration at 12 hours (C12). In arm 2, the corresponding GMRs were 0.75 (90% CI, .48-1.17) and 1.10 (90% CI, .61-2.00) for period 1 vs period 2, and 1.10 (90% CI, .78-1.55) and 1.68 (90% CI, .88-3.23) for period 1 vs period 3. CONCLUSIONS: The double dose of RAL overcompensated for RIF induction, but the standard dose was associated with only small decreases in AUC0-12 and C12 during RIF coadministration, warranting further evaluation in patients with HIV/tuberculosis coinfection. CLINICAL TRIALS REGISTRATION: NCT0082231.

High Cure Rate With 24 Weeks of Daclatasvir-Based Quadruple Therapy in Treatment-Experienced, Null-Responder Patients With HIV/Hepatitis C Virus Genotype 1/4 Coinfection: The ANRS HC30 QUADRIH Study.

BACKGROUND: Few direct anti-hepatitis C virus (HCV) agents have been studied in difficult-to-treat null responder and cirrhotic human immunodeficiency virus (HIV)-coinfected patients. Daclatasvir and asunaprevir combined with pegylated interferon/ribavirin (peg-IFN/RBV) have shown promising results in HCV-monoinfected patients. METHODS: An open-label, single-arm, phase 2 study was conducted in HIV/HCV genotype 1/4-coinfected patients who were null responders to prior peg-IFN/RBV standard therapy and on a raltegravir-based regimen with HIV RNA <400 copies/mL. They received a 4-week lead-in phase with peg-IFN/RBV, followed by 24 weeks of asunaprevir (100 mg twice daily), daclatasvir (60 mg once daily), and peg-IFN/RBV. The primary endpoint was sustained virologic response 12 weeks after the end of treatment (SVR12) using intent-to-treat analysis. RESULTS: Seventy-five patients were included, of whom 27 (36%) had cirrhosis. The median baseline CD4 count was 748 (interquartile range, 481-930) cells/µL. The global SVR12 rate was 96.0% (95% confidence interval [CI], 88.8%-99.2%; n = 72/75), 92.6% (95% CI, 75.7%-99.1%; n = 25/27) in cirrhotic patients, 94.6% (95% CI, 81.8%-99.3%; n = 35/37) in genotype 1 patients, and 97.4% (95% CI, 86.2%-99.9%; n = 37/38) in genotype 4 patients. Six patients (8%) stopped HCV therapy prematurely: 2 due to HCV breakthrough, 4 to adverse events (1 lung cancer, 3 infections). One patient with cirrhosis (with baseline platelet count <150 000 platelets/µL and albuminemia <35 g/L) died from multiorgan failure. Overall, 36 serious adverse events occurred in 21 (28%) patients. No HIV breakthrough was observed. CONCLUSIONS: In HIV/HCV genotype 1/4-coinfected null responders, a 24-week regimen combining daclatasvir, asunaprevir, and peg-IFN/RBV was associated with a very high cure rate. The safety profile was acceptable, even though cirrhotic patients with low albuminemia and platelets should be monitored closely. This combination is a new option in this difficult-to-treat population. CLINICAL TRIALS REGISTRATION: NCT01725542.