Antiviral Therapy

We aimed to determine the impact of inosine triphosphatase (ITPA) deficiency on ribavirin (RBV)-induced anaemia in HIV–HCV-coinfected patients receiving a triple therapy including the haematotoxic direct-acting antiviral agent boceprevir (BOC).

Patients of the ANRS HC27 BocepreVIH study were genotyped for two ITPA single nucleotide polymorphisms involved in ITPA deficiency. RBV trough concentration (C_trough) was determined at week (W)4 and W8. Impact of ITPA deficiency on anaemia, RBV C_trough, response and haematotoxicity (grade 3/4 anaemia, erythropoietin [EPO] use, RBV dose reduction or transfusion between day [D]0 and W8) was evaluated. Impact of RBV C_trough on anaemia was also studied.

Among the 63 genotyped patients, 33% had a predicted ITPA deficiency. ITPA deficiency was associated with a lower haemoglobin (Hb) decline both at W4 (-1.0 g/dl versus -2.1 g/dl; P=0.02) and W8 (-2.7 g/dl versus -4.1 g/dl; P=0.05). None of the patients with ITPA deficiency received EPO between D0–W8 versus 26% of patients without ITPA deficiency (P=0.01). RBV C_trough was associated with Hb decrease both at W4 and W8 and an RBV C_trough cutoff value of 2 μg/ml was significantly associated with a W4 Hb decline >2 g/dl. Haematotoxicity was significantly associated with a lower W4 Hb level (P=0.017), absence of ITPA deficiency (P=0.018) and higher RBV C_trough (P=0.012). ITPA deficiency, W4 RBV C_trough and gender were independent predictors of anaemia at W4. ITPA deficiency was not associated with virological response.

ITPA deficiency and RBV C_trough are still predictive of RBV-induced anaemia in HIV–HCV-coinfected patients treated with RBV combined with a first-generation direct antiviral agent.

This study aimed to determine the effect of tenofovir disoproxil fumarate (TDF) on bone metabolism and bone mass in HIV-infected adolescents.

This was a sub-study of a cross-sectional multicentre bone health trial that enrolled perinatally HIV-infected Thai and Indonesian adolescents (10–18 years) with viral suppression on antiretroviral therapy. Participants were classified into two groups as TDF users and non-users. Bone metabolism-related markers (25-hydroxyvitamin D [25-OHD], intact parathyroid hormone [iPTH], bone turnover biomarkers), and lumbar spine dual-energy X-ray absorptiometry were assessed. Bone mineral density (BMD)/bone mineral apparent density (BMAD) Z-scores were calculated.

Of 394 adolescents, 136 (34.5%) and 258 (65.5%) were TDF users and non-users, respectively. Among TDF users, median age (IQR) was 16.1 (14.7–17.4) years and TDF treatment duration (IQR) was 2.3 (1.4– 3.1) years. Among TDF non-users, median age (IQR) was 14.3 (12.6–16.4) years. BMD and BMAD Z-scores comparing TDF users with non-users were -0.8 and -0.6 (P=0.27), and -0.3 and -0.2 (P=0.58), respectively. The association between TDF use and iPTH elevation was intensified in adolescents with suboptimal vitamin D levels (25-OHD <30 ng/ml; P=0.001). TDF administration was positively associated with bone resorption marker (P=0.04) and negatively associated with bone formation marker (P=0.04). With data up to 4 years, neither association between TDF use and bone mass loss (BMD: P=0.09; BMAD: P=0.22), nor variation of bone mass Z-scores by TDF treatment duration (BMD: P=0.34; BMAD: P=0.58) was demonstrated.

Recent TDF administration was correlated with PTH elevation and bone turnover dysregulation but not with bone mass reduction in our cohort. A study with extended follow-up to ascertain TDF-associated bone mass deterioration is warranted.

Predictors of sustained virological response (SVR) to all-oral HCV regimens can inform nuanced treatment decisions. We evaluated effectiveness and identified predictors of SVR for ledipasvir/sofosbuvir ± ribavirin (LDV/SOF ±RBV) and ombitasvir/paritaprevir/ ritonavir + dasabuvir (OPrD) ±RBV in patients treated in routine practice.

Observational, intent-to-treat cohort of 21,142 genotype-1 patients initiating 8 or 12 weeks of LDV/SOF ±RBV or 12 weeks of OPrD ±RBV at any Veterans Affairs facility. Multivariate logistic regression models were constructed to model SVR and identify predictors.

SVR was 91.2% (9,781/10,720) for LDV/ SOF, 89.6% (3,266/3,646) for LDV/SOF+RBV, 91.7% (1,197/1,306) for OPrD and 87.8% (3,365/3,832) for OPrD+RBV. For LDV/SOF ±RBV, reduced odds of SVR occurred in African-Americans (0.80, 95% CI 0.70, 0.92, P<0.001), body mass index (BMI)<25 (0.77, 95% CI 0.66, 0.90, P <0.001), BMI≥30 (0.77, 95% CI 0.67, 0.89, P<0.001), proton pump inhibitors (PPIs; 0.81, 95% CI 0.71, 0.92, P<0.001), decompensated liver disease (0.58, 95% CI 0.45, 0.74, P <0.001) and FIB4>3.25 (0.60, 95% CI 0.53, 0.69, P <0.001). For OPrD ±RBV, FIB-4>3.25 negatively predicted SVR (0.72, 95% CI 0.59, 0.88, P<0.001). Detectable 4-week on-treatment HCV RNA≥15 IU/ml reduced SVR odds for both regimens (LDV/SOF ±RBV OR 0.49, 95% CI 0.41, 0.58, P<0.001; OPrD ±RBV OR 0.38, 95% CI 0.29, 0.50, P <0.001). Receipt of OPrD+RBV compared to LDV/SOF reduced odds of SVR (OR 0.70, 95% CI 0.62, 0.80, P <0.001). Mental health diagnosis did not impact likelihood of SVR.

The diversity and size of this cohort allowed for extensive examination of regimen-specific predictors of SVR. FIB-4>3.25 and detectable 4-week on-treatment HCV RNA had the greatest negative impact. African-American race, low or high BMI, and PPIs negatively impacted odds of SVR for LDV/SOF ±RBV Mental health diagnoses did not.

The clinical impact of transient episodes of HIV viraemia (viral blips) on virological failure and resistance development is not fully understood. Here we investigated the blip frequency and virological outcomes of HIV-1-infected subjects experiencing viral blips among treatment-naive subjects initiating therapy on rilpivirine (RPV)/emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF) or efavirenz (EFV)/FTC/TDF through 96 weeks of treatment.

Subjects treated with at least one dose of study drug and with at least one post-baseline HIV-1 RNA value were included in this analysis. All on-drug HIV-1 RNA data points and FDA snapshot outcome data through week 96 were utilized. A viral blip was defined as after achieving confirmed suppression (two consecutive HIV-1 RNA values <50 copies/ml), any HIV-1 RNA value ≥50 copies/ml preceded and followed by HIV-1 RNA <50 copies/ml.

Of the 717 subjects with confirmed suppression, 67 (9.3%) experienced ≥1 blip through week 96 with similar blip frequencies occurring in both treatment arms (10.7% RPV/FTC/TDF versus 8.0% EFV/FTC/TDF; P=0.25). A significantly higher proportion of subjects with baseline HIV-1 RNA >100,000 copies/ml experienced blips compared to subjects with baseline HIV-1 RNA ≤100,000 copies/ml and this was observed in both arms. Of 72 total blip events, 61 (85%) were low-level (50-199 copies/ml). Overall, among subjects with blips, 79% were virological successes at week 96, similar to those subjects without blips (83%; P=0.50). More subjects with blips ≥200 copies/ml experienced virological failure compared to subjects with blips <200 copies/ml (36.4% versus 7.1%; P=0.02).

Viral blips were infrequent and similar among subjects treated with RPV/FTC/TDF or EFV/FTC/TDF. Most blips were low-level and most subjects with blips remained virologically suppressed through week 96 without experiencing virological failure.

Asymptomatic cytomegalovirus (CMV) infection is associated with graft dysfunction and failure. However, no study assessed CMV viral load in terms of the risk for graft failure.

In a prospective cohort of kidney transplant recipients, we assessed the impact of CMV DNAemia on the overall graft survival and the incidence of moderate-to-severe interstitial fibrosis and tubular atrophy (IF/TA) in protocol biopsy at 36 months. CMV DNAemia was stratified by viral load in whole blood.

A total of 180 patients transplanted from October 2003 through January 2011 were included and followed for 4 years; 87 (48%) patients received 3-month prophylaxis with valacyclovir and 45 (25%) with valganciclovir; 48 (27%) were managed by pre-emptive therapy. Within 12 months of transplantation, CMV DNAemia developed in 102 (57%) patients with 36 (20%) having a viral load of ≥2,000 copies/ml. Multivariate Cox analysis identified CMV DNAemia as an independent risk factor for graft loss (hazard ratio 3.42; P=0.020); however, after stratification by viral load, only CMV DNAemia ≥2,000 copies/ml (hazard ratio 7.62; P<0.001) remained significant. Both early-onset (<3 months; P=0.048) and late-onset (>3 months; P<0.001) CMV DNAemia ≥2,000 copies/ml were risk factors for graft loss. The incidence of moderate-to-severe IF/TA was not significantly influenced by CMV DNAemia.

Kidney transplant recipients having CMV DNAemia with a higher viral load irrespective of the time to onset are at increased risk for graft loss.

Infants exhibit elevated influenza virus loads and prolonged viral shedding, which may increase the risk for resistance development, especially in cases of suboptimal exposure to antiviral therapy.

We performed a prospective surveillance of hospitalized infants undergoing oseltamivir therapy during the 2008–2009 and 2011–2012 influenza seasons at two paediatric hospitals in Germany. A total of 37 infants less than 1 year of age with laboratory confirmed influenza A(H3N2) infection received oseltamivir as per physician's order for 5 days (2008–2009 season: 2 mg/kg twice daily; 2011–2012 season: 2.0 mg/kg; 2.5 mg/kg and 3.0 mg/kg twice daily for infants <1 month; 2–3 months and 4–12 months, respectively). Virus load, the susceptibility to neuraminidase inhibitors (NAIs), and the presence of molecular markers of resistance to NAIs was assessed for influenza viruses recovered from respiratory samples collected at baseline and during follow-up visits.

Overall, 73% of the infants continued to shed viral RNA detectable by reverse transcription (RT)-PCR after dose number 10 of oseltamivir; 12 infants shed viruses, 2 of them (both 9 months of age) shed resistant viruses. Resistance was characterized by ≥1,000-fold increase of 50% inhibitory concentration (IC₅₀) for oseltamivir, up to 50-fold for zanamivir and elevated Km values when compared to susceptible A(H3N2) strains. Sanger sequencing revealed the selection of the NA-R292K substitution in both instances (after dose number 10 on day 6).

Our data suggest that it may be relevant to monitor antiviral resistance systematically in all infants, considering that the European Medicines Agency has recently extended the licensure for oseltamivir to include full-term infants.

In HBV-infected patients, hepatitis B e antigen (HBeAg) seroconversion is associated with better outcomes. Interleukin-18 (IL-18) controls hepatitis B replication in a mouse model. However, its role in treatment response in HIV–HBV-coinfected patients is unknown.

We enrolled 35 treatment-naive, HBeAg-positive, HIV–HBV-coinfected patients. HBV DNA, HIV RNA, CD4⁺ T-cell count, HBV surface antigen (HBsAg) quantification (qHBsAg), HBeAg quantification (qHBeAg) and IL-18 levels were measured prior to, at 24 and 48 weeks of HBV-active combination antiretroviral therapy (cART). Multivariate Poisson regression models with robust standard errors were used to determine factors associated with HBeAg seroconversion.

Twenty-one patients received tenofovir (TDF) + lamivudine (3TC) based cART while 14 patients received 3TC-based cART. After 48 weeks of treatment, 10 patients experienced HBeAg seroconversion. Compared with non-seroconverters, seroconverters had higher median HIV RNA (5.22 versus 4.58 log copies/ml; P=0.030), lower median qHBsAg (3.97 versus 4.76 log IU/ml; P=0.011), lower median qHBeAg (1.61 versus 3.01 log PEIU/ml; P=0.004) and marginally higher median IL-18 (2.70 versus 2.53 log pg/ml; P=0.068) prior to ART. In the multivariate regression, higher baseline IL-18 (adjusted relative risk [aRR] 2.99 per 1 log pg/ml increase; P=0.035), high HIV RNA (aRR 1.84 per 1 log copies/ml; P=0.029) and low qHBeAg (aRR 0.71 per 1 log PEIU/ml; P=0.029) were significantly associated with HBeAg seroconversion.

In HIV–HBV-coinfected patients with HBeAg positivity, higher IL-18 levels, HIV RNA load, as well as low qHBeAg prior to cART were associated with HBeAg seroconversion.

Tenofovir disoproxil fumarate (TDF)-based regimen is a treatment option for HIV-infected patients. TDF dose adjustment is recommended in patients with impaired renal function. We assessed the impact of TDF dose adjustment on renal function and tenofovir trough concentration.

Fourteen HIV patients for whom TDF dose was adjusted (1 tablet/48 h) because of estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m², and/or due to a tenofovir trough concentration >90 ng/ml between 2006 and 2013 were selected. The eGFR was measured at baseline and 3, 6 and 12 months after TDF dose adjustment.

A 50% TDF dose reduction resulted in a significant increase of the eGFR 3 months after dose adjustment (61.1 versus 72.8 ml/min/1.73 m²; P=0.003). Concomitantly, tenofovir trough concentration decreased from 175 to 66 ng/ml (P=0.009). Antiviral efficacy was maintained in all patients.

TDF dose adjustment combined with therapeutic drug monitoring may be useful especially in patients at risk of kidney dysfunction.

A strategy of protease inhibitor (PI) mono-therapy with re-introduction of triple therapy in those who rebound has been shown to be a safe and effective treatment simplification approach for long-term management. We sought evidence for cerebrospinal fluid (CSF) virological escape in patients on long-term PI monotherapy.

We performed lumbar puncture in asymptomatic participants with suppressed plasma HIV RNA after 96 weeks on the PI monotherapy arm (PI-mono) of the PIVOT trial. We also report CSF HIV RNA concentration in trial participants who were investigated for neurological/ neurocognitive symptoms during the trial regardless of study arm allocation.

All 11 asymptomatic participants on PI-mono who were tested had undetectable CSF HIV RNA at week 96. One of the three symptomatic participants on PI-mono had CSF HIV RNA of 1,895 copies/ml (undetectable in plasma) and neither of two symptomatic participants on triple therapy had CSF HIV RNA detected.

CSF virological escape appears rare in asymptomatic patients on PI monotherapy and may not warrant routine CSF monitoring, but patients with symptoms merit more concern.

Cerebrospinal fluid (CSF) HIV RNA is commonly used as a marker of compartmental antiviral activity in HIV-positive patients. Undetectable CSF HIV RNA levels have been associated with low CSF neopterin levels and better neurocognitive performances. The aim of this study was to analyse the prevalence and predictors of non-detectable CSF HIV RNA using a commercial assay.

In adult HIV-positive HAART-treated patients with confirmed plasma HIV RNA <50 copies/ml, CSF HIV RNA (with Roche Amplicor Assay) and neopterin were measured.

112 adult patients were included. Plasma and CSF HIV RNA were non-detectable (target not detected [TND]) in 29 (25.9%) and 36 (32.1%) patients, respectively. CSF TND was observed more frequently in patients with plasma TND (P=0.005, OR=3.87). CSF neopterin levels were associated with age (rho =0.333, P=0.002) and current (rho= -0.272, P=0.015) and nadir (rho =-0.240, P=0.038) CD4⁺ T-lymphocytes; the lowest CSF neopterin concentration was observed in patients with CSF TND versus other viral load strata (0.62 mg/dl versus 0.78 mg/dl; P=0.048).

Efficaciously treated HIV-positive patients with detectable plasma HIV RNA might imperfectly control CSF viral replication. Prospective studies addressing the management and neurocognitive consequences of CSF low-level viraemia are warranted.