Update on rilpivirine: a new potent non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV replication

Changes in renal, bone, lipid, and inflammation markers in HIV-1 patients after combination antiretroviral therapy simplification to dolutegravir monotherapy

Combination antiretroviral therapy (cART) can cause metabolic toxicities. How cART simplification to dual or monotherapies affects metabolic markers is unknown. We analyzed the metabolic effects of cART simplification to dolutegravir (DTG) monotherapy in the randomized clinical DOMONO (DOlutegravir MONOtherapy for HIV) trial including HIV-positive participants. Renal function, Framingham risk score (FRS), inflammation, and bone mineral density (BMD) with trabecular bone score (TBS) were measured during 48 weeks after simplification. The changes at 48 weeks by on-treatment analyses overall and for prior tenofovir disoproxil fumarate (TDF) exposure were analyzed separately, using Bonferroni corrected alpha (p = 0.00096). Ninety-five patients initiated DTG monotherapy, including 80 discontinuing TDF. At week 48, the switch to DTG monotherapy resulted in an expected −7.8 ml/min estimated glomerular filtration decline. In patients on prior TDF, proteinuria improved (p < 0.00096), but proximal tubular dysfunction proportions did not change. Fasting lipids, FRS, and the inflammation markers C-reactive protein and CD4:CD8 T-cell ratio remained stable. Lumbar spine BMD improved (+1.7%, p < 0.00096), while hip BMD and TBS remained comparable. Simplification of TDF-containing cART to DTG monotherapy ameliorated lumbar spine BMD and proteinuria with neutral effect on lipids and inflammation markers. Although DTG monotherapy should not be used in routine care and its role in strictly selected patients with primary HIV infection needs to be further elucidated, these observations remain relevant regarding DTG-based dual therapy without TDF. www.clinicaltrials.gov registration number: NCT02401828.

Antiviral Drugs

Viruses are major pathogenic agents causing a variety of serious diseases in humans, other animals, and plants.

Drugs that combat viral infections are called antiviral drugs. There are no effective antiviral drugs for many viral infections. However, there are several drugs for influenza, a couple of drugs for herpesviruses, and some new antiviral drugs for treatment of HIV and hepatitis C infections.

The arsenal of antivirals is complex. As of March 2014, it consists of approximately 50 drugs approved by the FDA, approximately half of which are directed against HIV. Antiviral drug creation strategies are focused on two different approaches: targeting the viruses themselves or targeting host cell factors.

Direct virus-targeting antiviral drugs include attachment inhibitors, entry inhibitors, uncoating inhibitors, protease inhibitors, polymerase inhibitors, nucleoside and nucleotide reverse transcriptase inhibitors, nonnucleoside reverse-transcriptase inhibitors, and integrase inhibitors.

Protease inhibitors (darunavir, atazanavir, and ritonavir), viral DNA polymerase inhibitors (acyclovir, valacyclovir, valganciclovir, and tenofovir), and an integrase inhibitor (raltegravir) are included in the list of Top 200 Drugs by sales for the 2010s.

Real-life rilpivirine resistance and potential emergence of an E138A-positive HIV strain in north-eastern France

OBJECTIVES

To assess the prevalence of resistance to rilpivirine and mutations at position 138 in reverse transcriptase and to identify associated epidemiological and biological characteristics.

METHODS

This retrospective study included 238 patients with available HIV-1 nucleotide sequences analysed at the Laboratory of Virology at the University Hospital of Nancy between January 2011 and June 2013. Resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) was evaluated according to the ANRS algorithm (version 23) and correlated with clinico-epidemiological and therapeutic data. The virus strains were analysed by evaluating the distance and distribution of the phylogenetic tree (MEGAv5).

RESULTS

Among previously treated patients (111/238, 46.6%), 68/111 (61.3%) had received NNRTIs; all were rilpivirine-naive. The prevalence of rilpivirine resistance in the whole cohort was 12.6% (30/238), and was 10.2% (13/127) and 15.3% (17/111) in naive and pre-treated patients, respectively. The E138A mutation was the most frequent mutation associated with resistance to rilpivirine (P < 0.0001). The prevalence of the E138A mutation tended to increase over time, from 3.6% (2/55) during the first half of 2011 to 9.3% (4/43) during the first half of 2013 (P = 0.0614). Seven viral strains from seven naive male patients positive for the E138A mutation appeared in the same cluster.

CONCLUSIONS

In our cohort of patients, we observed significantly increased resistance to rilpivirine, mostly because of the E138A mutation, probably due to an E138A strain circulating in newly diagnosed men who have sex with men. Taken together, our results emphasize the need to investigate the prevalence of rilpivirine resistance-associated mutations in the coming years both in France and abroad.

Transmitted drug resistance to rilpivirine among antiretroviral-naïve patients living with HIV from northern Poland

Introduction

Rilpivirine (RPV) is a second-generation non-nucleoside reverse transcriptase inhibitor (NNRTI) that was recently approved for the treatment of antiretroviral-naïve individuals with HIV-1 viral load of <100,000 copies/ml. As transmission of the drug resistance mutations to this NNRTI may affect treatment outcomes, the frequency of primary, RPV-associated drug resistance mutations was assessed in this study.

Methods

For the study, 244 viral genome sequences from antiretroviral-naïve individuals were obtained by bulk sequencing. RPV-associated mutations were divided into RPV resistance mutations (K101E/P, E138A/G/K/Q/R, V179L, Y181C/I/V, Y188L, H221Y, F227C and M230I/L) according to the International AIDS Society-USA (IAS-USA) mutation list and variants potentially affecting RPV susceptibility (L100I, K101H/T, E138S, V179F/D/G/T, G190A/E/S, F227L and M230V) based on the in vitro and in vivo data.

Results

IAS-USA RPV drug resistance mutations were found in 5.3% sequences, with E138A and E138G being the most common (3.7 and 0.8%, respectively), followed by K101E (0.4%) and Y181C (0.4%), with no significant differences in the frequency between subtype B and non-B clades. Mutations potentially reducing RPV susceptibility were found in 2.5% of sequences, and they included V179D (1.6%) and G190A (0.8%), with equal distribution among non-B (n=2, 2.5%) and subtype B (n=4, 2.5%) clades. Clustering of RPV mutations was infrequent.

Conclusions

Prevalence of RPV-associated drug resistance mutations was low in the analysed sample and did not vary across the subtypes. The frequency of variants with potential influence on RPV susceptibility was similar among non-B variants if compared to B clades. Transmitted drug resistance to RPV is uncommon, which makes this a good option for the treatment of ARV-naïve patients; however, genotype resistance testing should remain compulsory before starting an RPV-based regimen.

Synthesis and biological evaluation of novel quinoxalinone-based HIV-1 reverse transcriptase inhibitors

A series of novel quinoxalinone derivatives were identified as potent anti-HIV-1 agents with IC₅₀ values at 10⁻⁸ μmol L⁻¹ level.

The connection domain mutation N348I in HIV-1 reverse transcriptase enhances resistance to etravirine and rilpivirine but restricts the emergence of the E138K resistance mutation by diminishing viral replication capacity

Clinical resistance to rilpivirine (RPV), a novel nonnucleoside reverse transcriptase (RT) inhibitor (NNRTI), is associated an E-to-K mutation at position 138 (E138K) in RT together with an M184I/V mutation that confers resistance against emtricitabine (FTC), a nucleoside RT inhibitor (NRTI) that is given together with RPV in therapy. These two mutations can compensate for each other in regard to fitness deficits conferred by each mutation alone, raising the question of why E138K did not arise spontaneously in the clinic following lamivudine (3TC) use, which also selects for the M184I/V mutations. In this context, we have investigated the role of a N348I connection domain mutation that is prevalent in treatment-experienced patients. N348I confers resistance to both the NRTI zidovudine (ZDV) and the NNRTI nevirapine (NVP) and was also found to be associated with M184V and to compensate for deficits associated with the latter mutation. Now, we show that both N348I alone and N348I/M184V can prevent or delay the emergence of E138K under pressure with RPV or a related NNRTI, termed etravirine (ETR). N348I also enhanced levels of resistance conferred by E138K against RPV and ETR by 2.2- and 2.3-fold, respectively. The presence of the N348I or M184V/N348I mutation decreased the replication capacity of E138K virus, and biochemical assays confirmed that N348I, in a background of E138K, impaired RT catalytic efficiency and RNase H activity. These findings help to explain the low viral replication capacity of viruses containing the E138K/N348I mutations and how N348I delayed or prevented the emergence of E138K in patients with M184V-containing viruses.