Week 48 Resistance Analyses of the Once-Daily, Single-Tablet Regimen Darunavir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (D/C/F/TAF) in Adults Living with HIV-1 from the Phase III Randomized AMBER and EMERALD Trials

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg is being investigated in two Phase III trials, AMBER (NCT02431247; treatment-naive adults) and EMERALD (NCT02269917; treatment-experienced, virologically suppressed adults). Week 48 AMBER and EMERALD resistance analyses are presented. Postbaseline samples for genotyping/phenotyping were analyzed from protocol-defined virologic failures (PDVFs) with viral load (VL) ≥400 copies/mL at failure/later time points. Post hoc analyses were deep sequencing in AMBER, and HIV-1 proviral DNA from baseline samples (VL <50 copies/mL) in EMERALD. Through week 48 across both studies, no darunavir, primary PI, or tenofovir resistance-associated mutations (RAMs) were observed in HIV-1 viruses of 1,125 participants receiving D/C/F/TAF or 629 receiving boosted darunavir plus emtricitabine/tenofovir-disoproxil-fumarate. In AMBER, the nucleos(t)ide analog reverse transcriptase inhibitor (N(t)RTI) RAM M184I/V was identified in HIV-1 of one participant during D/C/F/TAF treatment. M184V was detected pretreatment as a minority variant (9%). In EMERALD, in participants with prior VF and genoarchive data (N = 140; 98 D/C/F/TAF and 42 control), 4% had viruses with darunavir RAMs, 38% with emtricitabine RAMs, mainly at position 184 (41% not fully susceptible to emtricitabine), 4% with tenofovir RAMs, and 21% ≥ 3 thymidine analog-associated mutations (24% not fully susceptible to tenofovir) detected at screening. All achieved VL <50 copies/mL at week 48 or prior discontinuation. D/C/F/TAF has a high genetic barrier to resistance; no darunavir, primary PI, or tenofovir RAMs were observed through 48 weeks in AMBER and EMERALD. Only one postbaseline M184I/V RAM was observed in HIV-1 of an AMBER participant. In EMERALD, baseline archived RAMs to darunavir, emtricitabine, and tenofovir in participants with prior VF did not preclude virologic response.

Switching to coformulated rilpivirine (RPV), emtricitabine (FTC) and tenofovir alafenamide from either RPV, FTC and tenofovir disoproxil fumarate (TDF) or efavirenz, FTC and TDF: 96-week results from two randomized clinical trials

Objectives

The single‐tablet regimen rilpivirine, emtricitabine and tenofovir alafenamide (RPV/FTC/TAF) for treatment of HIV‐1‐infected adults was approved based on bioequivalence. We assessed the clinical efficacy, safety and tolerability of switching to RPV/FTC/TAF from either RPV/FTC/tenofovir disoproxil fumarate (TDF) or efavirenz (EFV)/FTC/TDF.

Methods

We conducted two distinct randomized, double‐blind, active‐controlled, noninferiority trials in participants taking RPV/FTC/TDF (Study 1216) and EFV/FTC/TDF (Study 1160). Each study randomized virologically suppressed (HIV‐1 RNA < 50 copies/mL) adults (1:1) to switch to RPV/FTC/TAF or continue their current regimen for 96 weeks. We evaluated efficacy as the proportion with HIV‐1 RNA < 50 copies/mL using the Food and Drug Administration snapshot algorithm and prespecified bone and renal endpoints at week 96.

Results

We randomized and treated 630 participants in Study 1216 (RPV/FTC/TAF, n = 316; RPV/FTC/TDF, n = 314) and 875 in Study 1160 (RPV/FTC/TAF, n = 438; EFV/FTC/TDF, n = 437). In both studies, the efficacy of switching to RPV/FTC/TAF was noninferior to that of continuing baseline therapy at week 96, with respective percentages of patients with HIV RNA < 50 copies/mL being 89.2% versus 88.5% in Study 1216 [difference 0.7%; 95% confidence interval (CI) −4.3 to +5.8%] and 85.2% versus 85.1% in Study 1160 (difference 0%; 95% CI −4.8 to +4.8%). No participant on RPV/FTC/TAF developed treatment‐emergent resistance versus two on EFV/FTC/TDF and one on RPV/FTC/TDF. Compared with continuing baseline therapy, significant improvements in bone mineral density and renal tubular markers were observed in the RPV/FTC/TAF groups (P < 0.001).

Conclusions

Switching to RPV/FTC/TAF from RPV/FTC/TDF or EFV/FTC/TDF was safe and effective and improved bone mineral density and renal biomarkers up to 96 weeks with no cases of treatment‐emergent resistance.

Lipid-lowering interventions targeting proprotein convertase subtilisin/kexin type 9 (PCSK9): an emerging chapter in lipid-lowering therapy

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease that is mainly expressed in the liver but can also be found in the intestine and kidneys. PCSK9 promotes the degradation of low density lipoprotein receptors (LDLR) by reducing their recycling and targeting the receptors for lysosomal destruction, thereby decreasing the rate of removal of LDL-cholesterol from the circulation. Thus, interventions targeting PCSK9 by reducing its expression may lead to significant reductions of LDL-cholesterol and possibly decrease cardiovascular risk. The present review aims to present and discuss the current clinical and scientific data pertaining to lipid-lowering interventions targeting PCSK9.

CETP Inhibition: Past Failures and Future Hopes

The atheroprotective role of high-density lipoprotein cholesterol (HDL-C) in cardiovascular disease has been unequivocally established, and epidemiological data have clearly demonstrated a strong inverse relationship between HDL-C levels and the risk of cardiovascular events, which is independent of the low-density lipoprotein cholesterol (LDL-C) levels. Thus, it would be logical to hypothesize that raising HDL-C might potentially lead to a reduction of cardiovascular risk. Cholesteryl ester transfer protein (CETP) promotes the transfer of cholesteryl esters from HDL to very low-density lipoprotein and LDL. Therefore, CETP inhibition raises HDL-C levels and decreases LDL-C levels. The first trials with CETP inhibitors failed to show a reduction in cardiovascular events. However, newer CETP inhibitors with more favorable effects on lipids are presently being tested in clinical trials with the hope that their use may lead to a reduction in cardiovascular risk. This review aims to provide the current evidence regarding CETP inhibition, as well as the clinical and scientific data pertaining to the new CETP inhibitors in development.

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.

SWIFT: prospective 48-week study to evaluate efficacy and safety of switching to emtricitabine/tenofovir from lamivudine/abacavir in virologically suppressed HIV-1 infected patients on a boosted protease inhibitor containing antiretroviral regimen

BACKGROUND

In the United States, emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) is a preferred nucleoside reverse transcriptase inhibitor (NRTI) backbone with lamivudine/abacavir (3TC/ABC) as a commonly used alternative. For patients infected with human immunodeficiency virus (HIV-1) virologically suppressed on a boosted protease inhibitor (PI) + 3TC/ABC regimen, the merits of switching to FTC/TDF as the NRTI backbone are unknown.

METHODS

SWIFT was a prospective, randomized, open-label 48-week study to evaluate efficacy and safety of switching to FTC/TDF. Subjects receiving 3TC/ABC + PI + ritonavir (RTV) with HIV-1 RNA < 200 c/mL ≥3 months were randomized to continue 3TC/ABC or switch to FTC/TDF. The primary endpoint was time to loss of virologic response (TLOVR) with noninferiority measured by delta of 12%. Virologic failure (VF) was defined as confirmed rebound or the last HIV-1 RNA measurement on study drug ≥200 c/mL.

RESULTS

In total, 311 subjects were treated in this study (155 to PI + RTV + FTC/TDF, 156 to PI + RTV + 3TC/ABC). Baseline characteristics were similar between the arms: 85% male, 28% black, median age, 46 years; and median CD4 532 cells/mm(3). By TLOVR through week 48, switching to FTC/TDF was noninferior compared to continued 3TC/ABC (86.4% vs 83.3%, treatment difference 3.0% (95% confidence interval, -5.1% to 11.2%). Fewer subjects on FTC/TDF experienced VF (3 vs 11; P = .034). FTC/TDF showed greater declines in fasting low-density lipoproteins (LDL), total cholesterol (TC), and triglycerides (TG) with significant declines in LDL and TC beginning at week 12 with no TC/HDL ratio change. Switching to FTC/TDF showed improved NCEP thresholds for TC and TG and improved 10-year Framingham TC calculated scores. Decreased estimated glomerular filtration rate [corrected] (eGFR) was observed in both arms with a larger decrease in the FTC/TDF arm.

CONCLUSIONS

Switching to FTC/TDF from 3TC/ABC maintained virologic suppression, had fewer VFs, improved lipid parameters and Framingham scores but decreased eGFR. CLINICALTRIALS.GOV IDENTIFIER: NCT00724711.

Low-abundance HIV species and their impact on mutational profiles in patients with virological failure on once-daily abacavir/lamivudine/zidovudine and tenofovir

Background

HIV clonal genotypic analysis (CG) was used to investigate whether a more sensitive analysis method would detect additional low-abundance mutations compared with population genotyping (PG) in antiretroviral-naive patients who experienced virological failure (VF) during treatment with abacavir/lamivudine/zidovudine and tenofovir.

Methods

HIV was analysed by PG and CG (771 baseline and 657 VF clones) from subjects with VF (confirmed HIV RNA ≥ 400 copies/mL at 24–48 weeks).

Results

Fourteen of 123 subjects (11%) met VF criteria; their median baseline HIV RNA was 5.4 log₁₀ copies/mL, and 4.0 log₁₀ copies/mL at VF. By baseline PG, 2/14 had HIV-1 with nucleoside reverse transcriptase inhibitor (NRTI) or non-NRTI mutations. By baseline CG, 9/14 had HIV-1 with NNRTI and/or NRTI mutations; 7/9 had study drug-associated mutations. By PG at VF, 10/14 had selected for resistance mutations [2, K65R; 1, M184V; and 7, thymidine analogue mutations (TAMs) ± M184V]. By CG at VF, for subjects with TAMs, T215F was more commonly detected (5/14 samples) than T215Y (2/14). For one subject who selected K65R at VF, both K65R-containing clones and TAM-containing clones (both T215A and T215F) were observed independently but not conjunctively in the same clone in a post-VF sample.

Conclusions

The majority of subjects with VF had major and minor mutations detected at VF; CG detected additional low-abundance variants at baseline and VF that could have influenced mutation selection pathways. Both PG and CG data suggest TAMs, not K65R selection, are the preferred resistance route, biased towards 215F selection. No HIV clone contained both K65R and T215F/Y mutations, suggesting in vivo antagonism between the two mutations. The once-daily zidovudine usage and high baseline viraemia may also have contributed to rapid selection of HIV with multiple mutations in VFs.

Melanoma cell lines from different stages of progression and their biological and molecular analyses

The biological and molecular characteristics of cell lines from metastatic melanomas have been extensively studied but less is known about cells from the biologically earliest stage of primary melanoma. The overall success rate of establishing permanent cell lines from such lesions is only 10% of that for biologically late primary or metastatic melanomas, although our laboratory now has eight cell lines available. The cells are immortal but show reduced or no proliferation in soft agar and immunodeficient mice when compared with primary melanomas from the biologically advanced vertical growth phase. Metastatic melanoma cell lines from patients with familial melanoma or xeroderma pigmentosum are biologically similar to those from patients with spontaneous melanomas. Irrespective of the malignant stages, deletions and mutations can occur in exons 1-3 of the p16INK4A gene. DNA fingerprinting was then employed to demonstrate the uniqueness of individual cell lines and to confirm the identity of cell lines derived from same patients. These cell lines are an excellent resource to investigate melanoma progression.

Gastrointestinal tract colonization with vancomycin-resistant Enterococcus faecium in an animal model

Vancomycin-resistant enterococci have become important nosocomial pathogens in many institutions. The gastrointestinal tract of susceptible hosts serves as the likely reservoir from which the organism is disseminated. To study factors promoting colonization and the efficacy of decontamination therapy with antimicrobial agents, a model of gastrointestinal colonization with vancomycin-resistant Enterococcus faecium was developed in CF1 mice. At baseline, all animals were colonized with non-vancomycin-resistant enterococci (5.0 log10 CFU/g), but vancomycin-resistant organisms were not detectable. Following gastric inoculation with 5 x 10(8) CFU of a clinical isolate of vancomycin-resistant E. faecium, the strain transiently colonized the gastrointestinal tract of 100% of mice but was undetectable by Day 14 (< or = 2.7 log10 mean CFU/g). In animals who received 5 mg of streptomycin per ml or 250 micrograms of vancomycin per ml in drinking water, colonization with the organism occurred at significantly higher bacterial counts than in controls at 7 days following inoculation (9.4 for vancomycin, 9.2 for streptomycin, and 5.1 log10 mean CFU/g for controls; P < 0.05). Fecal concentrations of vancomycin-resistant E. faecium persisted at high counts through Day 22 in mice receiving these antibiotics, but low counts were also still detected in 3 of 10 control animals. In mice with previously established vancomycin-resistant E. faecium colonization, oral administration of ramoplanin, a lipoglycodepsipeptide to which the strain was susceptible, suppressed growth of all enterococci in feces, including the vancomycin-resistant strain after 7 days of therapy (< or = 3.1 and < or = 3.3 log10 mean CFU/g for vancomycin and streptomycin groups, respectively). All mice had a recurrence of colonization with vancomycin-resistant E. faecium after the ramoplanin was discontinued. In summary, this animal model demonstrates the importance of antibiotics in predisposing to gastrointestinal colonization with vancomycin-resistant Enterococcus spp. Although treatment with ramoplanin temporarily suppressed the organism, recurrence of colonization due to relapse or reinfection occurred.

Developmental issues in deaf children

This article presents an overview of the development of deaf children. The central difficulty for these children is acquiring language; however, delays in language development are not inevitable. Deaf children of deaf parents are less likely to experience problems in this and other areas of development than are deaf children of hearing parents, although this latter group represents 90% of the population of deaf children. Much more needs to be known about the development of deaf children and the environmental strategies that maximize the development of children with a major sensory deficit. The implications for caregiving to deaf children and their families are discussed.

Repression of rearranged mu gene and translocated c-myc in mouse 3T3 cells X Burkitt lymphoma cell hybrids

The productively rearranged immunoglobulin mu chain gene and the translocated cellular oncogene c-myc are transcribed at high levels both in human Burkitt lymphoma cells carrying the t(8;14) chromosome translocation and in mouse plasmacytoma X Burkitt lymphoma cell hybrids. In the experiments reported here these genes were found to be repressed in mouse 3T3 fibroblast X Burkitt lymphoma cell hybrids. Such repression probably occurs at the transcriptional level since no human mu- and c-myc messenger RNA's are detectable in hybrid clones carrying the corresponding genes. It is therefore concluded that the ability to express these genes requires a differential B cell environment. The results suggest that the 3T3 cell assay may not be suitable to detect oncogenes directly involved in human B cell oncogenesis, since 3T3 cells apparently are incapable of transcribing an oncogene that is highly active in malignant B cells with specific chromosomal translocations.

Portrait of a pusher--"mother"

The authors describe a case history of a drug pusher who has represented a special problem for their drug treatment program, since he functions symbiotically with this program, and is intimately involved with its clientele. Such a development, in the course of a drug treatment program, has implications for the practicality of the treatment approach. Methods of coping are discussed.