Bictegravir/emtricitabine/tenofovir alafenamide in older individuals with HIV: Results of a 96-week, phase 3b, open-label, switch trial in virologically suppressed people ≥65 years of age

OBJECTIVES

Bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) is an effective treatment for HIV-1 infection; however, clinical trial data in older people living with HIV (PLWH) are lacking. The primary 24-week and secondary 48-week analyses of study GS-US-380-4449 (NCT03405935), which assessed the efficacy and safety of switching to B/F/TAF in older PLWH, have been published. Here we report the results of the final 96-week analyses from the study.

METHODS

In this 96-week, phase 3b, open-label, single-arm trial, virologically suppressed PLWH aged ≥65 years switched from elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide or a tenofovir disoproxil fumarate-based regimen to B/F/TAF. Viral suppression, resistance, immune response, safety, tolerability and adherence were evaluated through week 96.

RESULTS

Of 90 participants screened, 86 were enrolled and switched to B/F/TAF. No participants had HIV-1 RNA ≥50 copies/ml (by FDA Snapshot algorithm) at weeks 72 or 96; virologic suppression rates were 94.2% (81/86; 95% CI 87.0-98.1) and 74.4% (64/86; 95% CI 63.9-83.2), respectively. No treatment-emergent resistance was observed, and CD4 counts remained stable. There were no study drug-related serious adverse events. Three participants experienced drug-related treatment-emergent adverse events that led to premature drug discontinuation. There were no clinically relevant changes from baseline to week 96 in fasting lipid parameters, and the median change in body weight at week 96 was 0.0 kg (IQR -2.3, 2.0). Median self-reported adherence was 100% (IQR 100-100%).

CONCLUSIONS

Switching to B/F/TAF is an effective long-term option for virologically suppressed adults ≥65 years of age, with favourable safety and tolerability profiles in this population.

Switching to Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide in Adults With HIV and M184V/I Mutation

BACKGROUND

The ability of elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) to maintain virologic suppression in participants with M184V and/or M184I resistance mutations from historical genotypic reports when switching from a tenofovir disoproxil fumarate-based or abacavir (ABC)-based regimen was investigated.

SETTING

Phase IIIb, 48-week, open-label, single-arm, multicenter, clinical trial (NCT02616029).

METHODS

Virologically suppressed adults with HIV and documented M184V/I on historical genotypic records switched to E/C/F/TAF from a tenofovir disoproxil fumarate-based or ABC-based regimen. The primary end point was HIV-1 RNA of <50 copies per milliliter at week 12 using pure virologic response (PVR). Secondary end points included HIV-1 RNA of <50 copies per milliliter at weeks 24/48 (PVR) and at weeks 12, 24, and 48 (Food and Drug Administration snapshot algorithm), and change in CD4+ count at weeks 12, 24, and 48.

RESULTS

M184V alone was reported in 82.8% of 64 participants; 9.4% and 7.8% had M184I and M184V/I, respectively, and 43.8% had archived M184V/I (baseline DNA). All (62/62 with available data, 100%, 95% confidence interval 94.2% to 100%) participants maintained PVR at weeks 12, 24, and 48. By Food and Drug Administration snapshot algorithm, one participant had HIV-1 RNA of ≥50 copies per milliliter (week 12); confirmatory HIV-1 RNA was <50 copies per milliliter. No significant changes were observed in CD4+ cell count. Drug-related adverse events (AEs) were reported by 10 (15.6%) participants. Six (9.4%) and 5 (7.8%) participants had grade 3-4 AEs or serious AEs, respectively (none drug related).

CONCLUSIONS

The presence of the resistance mutations M184V/I did not jeopardize the efficacy of switching to E/C/F/TAF in virologically suppressed adults. High rates of virologic suppression were maintained throughout 48 weeks of therapy and treatment was well tolerated.

Bictegravir/Emtricitabine/Tenofovir Alafenamide in Virologically Suppressed People with HIV Aged ≥ 65 Years: Week 48 Results of a Phase 3b, Open-Label Trial

Introduction

We report the 48-week results of an ongoing study to assess the efficacy and safety of switching older people with HIV to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF).

Methods

This was a 96-week, phase 3b, open-label, single-arm study (GS-US-380-4449; NCT03405935). Virologically suppressed individuals aged ≥ 65 years receiving elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide or a tenofovir disoproxil fumarate-based regimen were switched to B/F/TAF. Primary endpoint was the percentage of participants with HIV-1 RNA < 50 copies/ml at week 24.

Results

Eighty-six participants (median age 69 [range 65–80] years; 87% male; 95% white) were enrolled and treated in five European countries. Rates of virologic suppression were 97.7% at week 24 and 90.7% at week 48; none had HIV-1 RNA ≥ 50 copies/ml, and 100% had virologic suppression by missing = excluded analysis at both time points. No treatment-emergent resistance was observed. There were no grade 3–4 study drug-related adverse events (AEs) or study drug-related serious AEs or deaths. Three AEs led to premature discontinuation; one (moderate abdominal discomfort) was attributed to the study drug by the investigator. At week 48, median changes from baseline in weight and estimated glomerular filtration rate were + 0.1 kg (interquartile range [IQR] − 1.0, 2.3) and − 6.0 ml/min (IQR − 10.2, 0.0), respectively. There were no clinically relevant changes from baseline to week 48 in fasting lipid parameters. Treatment satisfaction improved, and health-related quality of life was maintained from baseline through week 48. Median adherence to the study drug was 98.6% (IQR 96.0, 100).

Conclusions

Switching to B/F/TAF was effective and well tolerated through 48 weeks in virologically suppressed adults aged ≥ 65 years.

Trial Registration

ClinicalTrials.gov identifier, NCT03405935.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00419-5.

Bone mineral density in virologically suppressed people aged 60 years or older with HIV-1 switching from a regimen containing tenofovir disoproxil fumarate to an elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide single-tablet regimen: a multicentre, open-label, phase 3b, randomised trial

BACKGROUND

Tenofovir alafenamide is associated with less renal and bone toxicity than tenofovir disoproxil fumarate and might improve the long-term safety of antiretroviral therapy. We aimed to investigate the effect on bone mineral density of switching from a regimen containing tenofovir disoproxil fumarate to one containing tenofovir alafenamide in participants aged 60 years and older.

METHODS

We did a prospective, open-label, multicentre, randomised trial in 36 European centres. Participants were virologically suppressed (HIV-1 RNA <50 copies per mL), aged 60 years or older, on a tenofovir disoproxil fumarate-containing regimen and were randomly assigned (2:1) via an interactive web-response system to open-label elvitegravir (150 mg), cobicistat (150 mg), emtricitabine (200 mg), and tenofovir alafenamide (10 mg) daily or continued therapy containing tenofovir disoproxil fumarate (300 mg). Participants were stratified by spine and hip bone mineral density categories. Primary endpoints were change from baseline to week 48 in spine and hip bone mineral density with a null hypothesis of zero between-group difference tested at a significance level of 0·05. This study was registered with ClinicalTrials.gov, NCT02616783.

FINDINGS

Between Dec 22, 2015, and March 21, 2018, 167 participants were randomly assigned to elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide (n=111 [66%]) or tenofovir disoproxil fumarate (n=56 [34%]). One participant in the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide group did not receive treatment and was excluded from all analyses. At week 48, the mean percentage change in spine bone mineral density was 2·24% (SD 3·27) in the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide group and -0·10% (3·39) in the tenofovir disoproxil fumarate group (between-group difference 2·43% [95% CI 1·34-3·52]; p<0·0001), and mean percentage change in hip bone mineral density was 1·33% (2·20) in the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide group and -0·73% (3·21) in the tenofovir disoproxil fumarate group (difference 2·04% [1·17-2·90]; p<0·0001). The most common adverse events were nasopharyngitis (12 [11%]), back pain (nine [8%]), and diarrhoea (eight [7%]) in the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide group; and bronchitis (six [11%]), vitamin D deficiency (four [7%]), and arthralgia (four [7%]) in the tenofovir disoproxil fumarate group. 22 (20%) participants in the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide group and one (2%) participant in the tenofovir disoproxil fumarate group had an adverse event that was considered to be related to treatment. No treatment-related serious adverse events were observed. The proportions of adverse events leading to premature treatment discontinuation were similar between groups (four [4%] in the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide group; and one (2%) in the tenofovir disoproxil fumarate group).

INTERPRETATION

The significantly improved bone mineral density, overall safety, and efficacy data show the feasibility of switching from a regimen containing tenofovir disoproxil fumarate to elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide in virologically suppressed people living with HIV aged 60 years or older.

FUNDING

Gilead Sciences.

HIV/HCV therapy with ledipasvir/sofosbuvir after randomized switch to emtricitabine-tenofovir alafenamide-based single-tablet regimens

INTRODUCTION

Guidelines advocate the treatment of HCV in all HIV/HCV co-infected individuals. The aim of this randomized, open-label study (ClinicalTrials.gov identifier: NCT02707601; https://clinicaltrials.gov/ct2/show/NCT02707601) was to evaluate the safety/efficacy of ledipasvir/sofosbuvir (LDV/SOF) co-administered with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or rilpivirine/F/TAF (R/F/TAF) in HIV-1/HCV co-infected participants.

METHODS

Participants with HIV-1 RNA <50 copies/mL and chronic HCV-genotype (GT) 1 (HCV treatment-naïve ± compensated cirrhosis or HCV treatment-experienced non-cirrhotic) were randomized 1:1 to switch to E/C/F/TAF or R/F/TAF. If HIV suppression was maintained at Week 8, participants received 12 weeks of LDV/SOF. The primary endpoint was sustained HCV virologic response 12 weeks after LDV/SOF completion (SVR12).

RESULTS

Of 150 participants, 148 received ≥1 dose of HIV study drug and 144 received LDV/SOF (72 in each F/TAF group; 83% GT1a, 94% HCV treatment-naïve, 12% cirrhotic). Overall, SVR12 was 97% (95% confidence interval: 93-99%). Black race did not affect SVR12. Of four participants not achieving SVR12, one had HCV relapse, one had HCV virologic non-response due to non-adherence, and two missed the post-HCV Week 12 visit. Of 148 participants, 96% receiving E/C/F/TAF and 95% receiving R/F/TAF maintained HIV suppression at Week 24; no HIV resistance was detected. No participant discontinued LDV/SOF or E/C/F/TAF due to adverse events; one participant discontinued R/F/TAF due to worsening of pre-existing hypercholesterolemia. Renal toxicity was not observed in either F/TAF regimen during LDV/SOF co-administration. In conclusion, high rates of HCV SVR12 and maintenance of HIV suppression were achieved with LDV/SOF and F/TAF-based regimens.

CONCLUSION

This study supports LDV/SOF co-administered with an F/TAF-based regimen in HIV-1/HCV-GT1 co-infected patients.

Efficacy and safety of elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide in Asian participants with human immunodeficiency virus 1 infection: A sub-analysis of phase 3 clinical trials

Background: The efficacy and safety of a single tablet regimen (STR) of elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) was analyzed in Phase 3 clinical trials in antiretroviral therapy (ART)-naive and ART-experienced Asian participants infected with human immunodeficiency virus (HIV)-1 through 96 or 144 weeks. Objective: In Asian population requiring treatment, it is imperative to have data specific to this group, particularly as there is a general concern that Asians with lower body weight have increased risk of tenofovir disoproxil fumarate (TDF)-related renal dysfunction. Methods: Studies -104 and 111 were randomized, double-blind, placebo-controlled, 144-week studies conducted in ART-naive participants, comparing E/C/F/TAF versus E/C/F/TDF. Study 109 was a randomized, open-label, 96-week study conducted in virologically suppressed, ART-experienced participants, who switched to E/C/F/TAF from ritonavir/cobicistat-boosted atazanavir ATV+(RTV or COBI) + F/TDF regimens, from non-nucleoside reverse transcriptase inhibitors (NNRTI) + F/TDF regimens, or from E/C/F/TDF. Study 112 was a single arm, open-label, 144-week study conducted in HIV suppressed, ART-experienced participants with mild-moderate renal impairment, who switched to E/C/F/TAF. Results: Asian participants in these studies had sustained efficacy safety and tolerability. In Study 104/111, Asian participants achieved 93% virologic suppression on TAF vs 88% on TDF at week 144. At baseline, there were numerically more Asians with median CD4 counts < 200 cells/uL and VL > 100,000 c/mL. In Study 109, 95% of Asians on TAF vs 86% on TDF maintained virologic suppression at week 96. Lastly, in Study 112, 91% maintained virologic suppression at week 144. There were no discontinuations due to renal AE, no cases of PRT or Fanconi syndrome in any of the studies.

Selected CNS Outcomes Among INSTI Antiretrovirals

Background

Higher rates of neuropsychiatric events among patients on dolutegravir (DTG) compared with other integrase inhibitors (INSTIs) have been reported from clinic cohorts and one blinded trial. We compared select neurological and psychiatric events in a large sample of patients treated with different INSTIs.

Methods

The Quintiles IMS database, which includes pharmacy and medical claims records, was examined for HIV infected patients treated from 2006 to 2016 with DTG (TIVICAY/TRIUMEQ), elvitegravir (EVG, STRIBILD), or raltegravir (RAL, ISENTRESS). The dependent variable outcomes were insomnia/sleep disturbance and depression. A propensity score was created to adjust for variables associated with treatment with a particular INSTI including age, gender, year of initial INSTI exposure, and enrollment time. Multivariate Poisson mixed models were used to generate incidence rate ratios (IRRs).

Results

Records for 54,151 distinct HIV-infected patients treated with DTG, EVG, or RAL were identified. In the multivariate model the rate of insomnia/sleep disturbance events was significantly higher for patients treated with DTG vs. EVG (IRR 1.21 [95% CI 1.09–1.33, P < 0.001]), but was not significantly different when comparing DTG to RAL (IRR 1.04 [95% CI 0.94–1.14, P = 0.459]). Likewise, the rate of incident depression was significantly higher for patients treated with DTG vs. EVG (IRR 1.18 [95% CI 1.09–1.27, P < 0.001], but not when comparing DTG to RAL (IRR 0.93 [95% CI 0.87 – 1.01, P = 0.068]).

Conclusion

In this analysis using a large healthcare database, significantly higher adjusted rates of both incident insomnia/sleep disturbances (21% more) and depression (18% more) were found among patients treated with DTG compared with EVG. In contrast, a significant difference in the rates of either outcome was not observed when comparing DTG and RAL. Further studies are warranted to determine the risk of neuropsychiatric events in patients treated with different INSTIs.

Disclosures

D. Wohl, Gilead Sciences: Consultant and Investigator, Consulting fee and Research grant; Viiv: Consultant and Investigator, Consulting fee and Research grant; Janssen: Consultant, Consulting fee; Bristol-Myers Squibb: Consultant, Consulting fee; A. Mills, Gilead Sciences: Consultant, Investigator and Speaker’s Bureau, Consulting fee, Research grant and Speaker honorarium; Viiv: Consultant and Investigator, Consulting fee and Research grant; Merck: Consultant, Investigator and Speaker’s Bureau, Consulting fee, Research grant and Speaker honorarium; Janssen: Investigator, Research grant; Bristol-Myers Squibb: Investigator, Research grant; Sangamo Bio Sciences: Investigator, Research grant; R. Mera, Gilead Sciences: Employee and Shareholder, Salary; D. Piontkowsky, Gilead Sciences: Employee and Shareholder, Salary

Switching to the single-tablet regimen of elvitegravir, cobicistat, emtricitabine, and tenofovir DF from non-nucleoside reverse transcriptase inhibitor plus coformulated emtricitabine and tenofovir DF regimens: Week 96 results of STRATEGY-NNRTI

BACKGROUND

HIV-1-infected, virologically suppressed adults wanting to simplify or change their non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens may benefit from switching to the single-tablet regimen of elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (E/C/F/TDF).

OBJECTIVE

We examined differences in the proportion of participants with HIV-1 RNA < 50 copies/mL (Snapshot analysis), change in CD4 cell count, safety, and patient-reported outcomes in participants switching to E/C/F/TDF from an NNRTI + FTC/TDF (TVD) regimen.

METHODS

STRATEGY-NNRTI was a 96-week, phase 3b, randomized, open-label, study examining the efficacy, safety, and tolerability of switching to E/C/F/TDF in virologically suppressed individuals (HIV-1 RNA < 50 copies/mL) on an NNRTI + TVD regimen. Participants were randomized to switch or remain on their NNRTI-based regimen (no-switch).

RESULTS

At Week 96, 87% (251/290) of switch and 80% (115/143) of no-switch participants maintained HIV-1 RNA < 50 copies/mL (difference 6.1%; 95% CI -1.3 to 14.2%; p = 0.12) according to the FDA-defined snapshot algorithm. Both groups had similar proportions of subjects with virologic failure (2.8% switch, 1.4% no-switch). Discontinuations resulting from adverse events were infrequent (3% [9/291] switch, 2% [3/143] no-switch). Three switch participants (1%) discontinued due to renal adverse events (2 of the 3 before Week 48). Switch participants reported significant improvements in neuropsychiatric symptoms by as early as Week 4, and which were maintained through Week 96.

CONCLUSIONS

E/C/F/TDF is safe and effective and reduces NNRTI-associated neuropsychiatric symptoms for virologically suppressed HIV-positive adults switching from an NNRTI plus FTC/TDF-based regimen.

An Indirect Comparison of Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate and Abacavir/Lamivudine + Dolutegravir in Initial Therapy

Objectives

The objective of this analysis is to perform an indirect comparison of elvitegravir, cobicistat, emtricitabine and tenofovir DF (E/C/F/TDF) to abacavir/lamivudine and dolutegravir (ABC/3TC + DTG) by using 2 trials evaluating each of these regimens in comparison to efavirenz, emtricitabine and tenofovir DF (EFV/FTC/TDF).

Methods

An indirect comparison was performed by using a generalization of Bucher's methodology to calculate risk differences. Two phase III clinical trials (GS-US-236-0102 and SINGLE—described above) were used.

Results

Results of the indirect comparison showed no statistically significant risk difference of the efficacy endpoint of achieving HIV RNA < 50 copies/mL between E/C/F/TDF and ABC/3TC + DTG for the ITT population at weeks 48, 96 and 144: respectively -3.7% (CI95% = [-10.8%; 3.4%]), -5.2% (CI95% = [-13.2%; 2.8%]) and -3.1% (CI_95% = [-12.0%; 5.7%]). There was no statistically significant differences in the risk difference for serious adverse events (5.7% (CI95% = [-2.2%; 12.3%])), drug related adverse event (2.7% (CI95% = [-7.0%;12.4%])), drug related serious adverse event (0.8% (CI95% = [-1.6%;3.2%])) and death (0.5% (CI95% = [-0.8%;1.8%])), respectively, between E/C/F/TDF and ABC/3TC + DTG. A significant difference was found for discontinuation due to adverse events with a higher rate for E/C/F/TDF (difference = 8.6% (CI95% = [3.3%; 13.9%])). There was also no statistically significant risk difference of the viral resistance of 1.2% (CI95% = [-1.2; 3.7]) between E/C/F/TDF and ABC/3TC + DTG at week 48, 1.7% at week 96 (CI95% = [-1.1; 4.5]) and 2.2% (CI95% = [-1.0; 5.4]) at week 144.

Drug Interactions with Cobicistat- or Ritonavir-Boosted Elvitegravir

Cobicistat and ritonavir are structurally distinct compounds that both potently inhibit cytochrome P450 (CYP) 3A, the metabolizing enzyme primarily responsible for the elimination of several antiretroviral medications, and, as such, are pharmacokinetic boosters for antiretroviral agents that require longer dosing intervals. Recently, cobicistat was approved for the treatment of HIV-1 infection in treatment-naive adults as a component of a single-tablet regimen consisting of cobicistat-boosted elvitegravir plus emtricitabine and tenofovir disoproxil fumarate. While studies have demonstrated that boosting with either cobicistat or ritonavir results in comparable plasma exposure of the target antiretroviral agent, a better understanding of drug-drug interactions between cobicistat- and ritonavir-boosted antiretrovirals and other medications will inform treatment decisions in HIV-infected patients. In connection with their distinct structural properties, COBI and RTV differ with respect to their drug-drug interaction profiles. Compared with ritonavir, cobicistat lacks induction potential and is a more specific inhibitor of 3A and therefore, has reduced effects on other CYP isoforms. To date, more studies have assessed ritonavir drug-drug interactions with other medications than have assessed cobicistat drug-drug interactions. The objective of this article is to review the drug-drug interactions when cobicistat- or ritonavir-boosted elvitegravir, cobicistat, or elvitegravir/cobicistat/emtricitabine/tenofovir are coadministered with antiretroviral therapies or drugs that are either substrates, inducers, or inhibitors of the CYP3A metabolic pathway, as well as with drugs that alter intra-gastric pH or are substrates of P-gp, in order to inform the proper use of elvitegravir/cobicistat/emtricitabine/tenofovir.

Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate in Asian Subjects with Human Immunodeficiency Virus 1 Infection: A Sub-Analysis of Phase 3 Clinical Trials

The efficacy and safety of a single tablet regimen (STR) of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF) were analyzed in Phase 3 clinical trials in antiretroviral therapy (ART)-naïve and ART-experienced Asian subjects infected with human immunodeficiency virus (HIV)-1. Studies GS-US-236-102 and GS-US-236-103 were randomized, double-blind, placebo-controlled, 144-week studies conducted in ART-naïve subjects, comparing E/C/F/TDF versus efavirenz (EFV)/F/TDF or ritonavir-boosted atazanavir (ATV+RTV) plus emtricitabine/tenofovir DF (F/TDF), respectively. Studies GS-US-236-115 and GS-US-236-121 were randomized, open-label, 96-week long conducted in ART-experienced subjects, who switched to E/C/F/TDF from ritonavir-boosted protease inhibitors (PI+RTV)+F/TDF, or non-nucleoside reverse transcriptase inhibitors (NNRTI)+F/TDF regimens. The E/C/F/TDF appeared to have sustained efficacy and safety and was well tolerated in the small number of ART-naïve and ART-experienced Asian subjects.

Switching to coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir versus continuation of non-nucleoside reverse transcriptase inhibitor with emtricitabine and tenofovir in virologically suppressed adults with HIV (STRATEGY-NNRTI): 48 week results of a randomised, open-label, phase 3b non-inferiority trial

BACKGROUND

Coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (tenofovir) might be a safe and efficacious switch option for virologically suppressed patients with HIV who have neuropsychiatric side-effects on a non-nucleoside reverse transcriptase inhibitor (NNRTI) or who are on a multitablet NNRTI-containing regimen and want a regimen simplification. We assessed the non-inferiority of such a switch compared with continuation of an NNRTI-containing regimen.

METHODS

STRATEGY-NNRTI is a 96 week, international, multicentre, randomised, open-label, phase 3b, non-inferiority trial enrolling adults (≥18 years) with HIV-1 and plasma HIV RNA viral load below 50 copies per mL for at least 6 months on an NNRTI plus emtricitabine and tenofovir regimen. With a computer-generated randomisation sequence, we randomly allocated participants (2:1; blocks of six, stratified by efavirenz use at screening) to switch to coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir (switch group) or continue the NNRTI plus emtricitabine and tenofovir regimen (no-switch group). Key eligibility criteria included no history of virological failure and an estimated glomerular filtration rate of 70 mL per min or greater. The primary endpoint was the proportion of participants with plasma viral loads below 50 copies per mL at week 48 based on a snapshot algorithm with a non-inferiority margin of 12% (assessed by modified intention to treat). This trial is ongoing and is registered at ClinicalTrials.gov, number NCT01495702.

FINDINGS

Between Dec 29, 2011, and Dec 13, 2012, we randomly allocated 439 participants to treatment: 290 participants in the switch group and 143 participants in the no-switch group received treatment and were included in the modified intention-to-treat population. At week 48, 271 (93%) of 290 participants in the switch group and 126 (88%) of 143 participants in the no-switch group maintained plasma viral loads below 50 copies per mL (difference 5·3%, 95% CI -0·5 to 12·0; p=0·066). We detected no treatment-emergent resistance in either group. Safety events leading to discontinuation were uncommon in both groups: six (2%) of 291 participants in the switch group and one (1%) of 143 in the no-switch group.

INTERPRETATION

Coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir seems to be efficacious and well tolerated in virologically suppressed adults with HIV and might be a suitable alternative for patients on an NNRTI with emtricitabine and tenofovir regimen considering a regimen modification or simplification.

FUNDING

Gilead Sciences.

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.

Can Appendiceal CT Scanning be Utilized Effectively in Widespread General Surgical Practice?

Appendiceal CT was first reported in the radiological literature, and has only recently begun to appear in the surgical literature. Much of the enthusiasm surrounding appendiceal CT has come from several publications by relatively few authors. We report the feasibility of implementing an appendiceal CT scanning technique and our initial results. The charts (940) of all patients evaluated for possible appendicitis during a 3-month period were reviewed. A new appendiceal CT scanning technique was performed when the indication was solely to exclude appendicitis. The accuracy of this new technique Was determined. Eighty-seven patients were evaluated. Twenty-nine underwent appendiceal CT scanning. The accuracy of interpretation was 85 per cent. In 58 patients who did not receive an appendiceal CT scan the accuracy of surgical decision-making was 82 per cent. These values were not statistically different We found appendiceal CT scanning to be relatively easy to implement; and its accuracy was better than expected. Our accuracy does not match that reported in the literature by the pioneers of appendiceal CT scanning. More experience with this technique will be required to achieve consistently successful accuracy; the technique can then be utilized in surgical practice and potentially change the diagnostic approach to acute appendicitis.

Can appendiceal CT scanning be utilized effectively in widespread general surgical practice?

Appendiceal CT was first reported in the radiological literature, and has only recently begun to appear in the surgical literature. Much of the enthusiasm surrounding appendiceal CT has come from several publications by relatively few authors. We report the feasibility of implementing an appendiceal CT scanning technique and our initial results. The charts (940) of all patients evaluated for possible appendicitis during a 3-month period were reviewed. A new appendiceal CT scanning technique was performed when the indication was solely to exclude appendicitis. The accuracy of this new technique was determined. Eighty-seven patients were evaluated. Twenty-nine underwent appendiceal CT scanning. The accuracy of interpretation was 85 per cent. In 58 patients who did not receive an appendiceal CT scan the accuracy of surgical decision-making was 82 per cent. These values were not statistically different. We found appendiceal CT scanning to be relatively easy to implement; and its accuracy was better than expected. Our accuracy does not match that reported in the literature by the pioneers of appendiceal CT scanning. More experience with this technique will be required to achieve consistently successful accuracy; the technique can then be utilized in surgical practice and potentially change the diagnostic approach to acute appendicitis.