Long-acting injectable Cabotegravir + Rilpivirine for HIV maintenance therapy: Week 48 pooled analysis of phase 3 ATLAS and FLAIR trials

BACKGROUND: Long-acting (LA) injectable regimens are a potential therapeutic option in people living with HIV-1. SETTING: ATLAS (NCT02951052) and FLAIR (NCT02938520) were 2 randomized, open-label, multicenter, multinational phase 3 studies. METHODS: Adult participants with virologic suppression (plasma HIV-1 RNA <50 copies/mL) were randomized (1:1) to continue with their current antiretroviral regimen (CAR) or switch to the long-acting (LA) regimen of cabotegravir (CAB) and rilpivirine (RPV). In the LA arm, participants initially received oral CAB + RPV once-daily for 4 weeks to assess individual safety and tolerability, before starting monthly injectable therapy. The primary endpoint of this combined analysis was antiviral efficacy at week 48 (FDA Snapshot algorithm: noninferiority margin of 4% for HIV-1 RNA ≥50 copies/mL). Safety, tolerability, and confirmed virologic failure (2 consecutive plasma HIV-1 RNA ≥200 copies/mL) were secondary endpoints. RESULTS: The pooled intention-to-treat exposed population included 591 participants in each arm [28% women (sex at birth), 19% aged ≥50 years]. Noninferiority criteria at week 48 were met for the primary (HIV-1 RNA ≥50 copies/mL) and key secondary (HIV-1 RNA <50 copies/mL) efficacy endpoints. Seven individuals in each arm (1.2%) developed confirmed virologic failure; 6/7 (LA) and 3/7 (CAR) had resistance-associated mutations. Most LA recipients (83%) experienced injection site reactions, which decreased in incidence over time. Injection site reactions led to the withdrawal of 6 (1%) participants. The serious adverse event rate was 4% in each arm. CONCLUSION: This combined analysis demonstrates monthly injections of CAB + RPV LA were noninferior to daily oral CAR for maintaining HIV-1 suppression

Electrochemical Education

The purpose of this site is to collect in one location resources useful to educators attempting to incorporate modern electrochemical techniques into the undergraduate chemistry curriculum. Contains links to material on experiments, equipment, proposal writing, etc

Effects of cattle manure and soil parent material on shallow groundwater quality

Abstract Livestock are a critical agricultural commodity in the Midwestern United States and are directly linked to row crop production. Chemical and manure nutrient application for row crop production has resulted in significant losses of nitrogen (N) and phosphorus (P) to downstream ecosystems causing environmental crises like seasonal hypoxia in the Gulf of Mexico. However, the use of cattle manure has multiple benefits over commercial fertilizer including increased soil carbon levels and improved nutrient cycling and should be considered a critical component for future agricultural production in Iowa. In this study, we evaluated influences of bedded cattle manure and commercial fertilizer on groundwater quality in a field with varying soil parent material of glacial till and colluvium in eastern Iowa. We found that soil parent material predominately influenced groundwater quality. Multiple water quality parameters including nitrate varied significantly (p < 0.0001). Nitrate concentrations were nearly double in colluvium compared to glacial till (13.2 ± 6.7 compared to 7.0 ± 3.6 mg/L, respectively). Further, nitrate concentrations averaged 12.2 ± 8.1 mg/L in areas receiving bedded cattle manure and were significantly higher (p < 0.0001) compared to areas receiving commercial fertilizer only, which averaged 8.6 ± 4.7 mg/L. Dissolved P was significantly lower (p < 0.05) in areas receiving bedded cattle manure averaging 0.13 ± 0.12 mg/L compared to 0.07 ± 0.04 mg/L in commercial fertilizer‐only areas. However, higher nitrate concentrations were likely linked to 70 kg/ha of additional N applied to manure areas by farm managers above corn removal rates. Overall, our results stress the importance of appropriate nutrient application rates and placement over nutrient source

Aquifer lithology affects shallow groundwater quality more than nitrogen fertilizer form and placement method in an Iowa agricultural field

Abstract Excessive nutrient loss threatens local and regional water resources, and many midwestern U.S. states are adopting nutrient reduction strategies to reduce export of N and P. A common practice to reduce N loss is improved fertilizer management. In this study, we used a strip trial design to assess the effects of split N application form (urea and urea ammonium nitrate [UAN]) and placement method (broadcast, coulter, Y‐drop) on corn (Zea mays L.) yields and shallow groundwater quality at an agricultural field at Kirkwood Community College in Cedar Rapids, IA. Twelve shallow monitoring wells were installed within the production field and sampled 14 times across a corn–soybean [Glycine max (L.) Merr.] rotation. Results showed that split application of UAN applied with either coulter injection or Y‐drop method produced approximately 8–11% higher corn yields than broadcast urea, but no statistically significant relation was found between groundwater quality and N form and placement method. Instead, we report that groundwater quality and levels were significantly influenced by variations in aquifer lithology. Groundwater within fine‐textured glacial till had significantly higher dissolved reactive P, SO4, and specific conductivity, whereas groundwater within the sand aquifer had a deeper water table and had higher NO3–N and dissolved oxygen. Study results suggest aquifer lithology can play a much larger role than varying the N form and application method on shallow groundwater quality in agricultural fields

Pilot Study of Once-Daily Simplification Therapy with Abacavir/Lamivudine/Zidovudine and Efavirenz for Treatment of HIV-1 Infection

Objective: The purpose of this pilot study was to explore the efficacy and safety of the abacavir/lamivudine/zidovudine fixed-dose combination tablet administered as two tablets once daily (qd) versus one tablet twice daily (bid) in combination with efavirenz (EFV). Method: This was a prospective, randomized, open-label, multicenter study with a 24-week treatment period in 7 outpatient HIV clinics in the United States. Patients currently receiving an initial regimen of abacavir/lamivudine/zidovudine bid plus EFV qd for at least 6 months with HIV-1 RNA <50 copies/mL for at least 3 months and a screening CD4+ cell count ≥200 cells/mm 3 were eligible. Thirty-six patients enrolled, and 35 (97%) completed the study. Participants were randomized to switch to 2 tablets of abacavir/lamivudine/zidovudine qd plus EFV qd (QD arm) or continue current treatment (BID arm) for 24 weeks. Results: Efficacy, safety, and adherence were evaluated. Median baseline CD4+ cell count was 521 cells/mm 3 . At week 24, HIV-1 RNA <50 copies/mL was achieved for 94% of participants in the QD arm and 89% in the BID arm by intent-to-treat, missing = failure analysis (95% confidence interval for difference: ≥0.29 to +0.18, p = 1.000). At week 24, median CD4+ cell count change from baseline was +26 cells/mm 3 for the QD arm and -39 cells/mm 3 for BID arm. One patient randomized to the QD arm met virologic failure criteria (confirmed HIV-1 RNA >120 copies/mL) at week 20 and viral genotype showed M184V. After failure, this patient revealed he never took EFV throughout the entire study after randomization, effectively receiving only abacavir/lamivudine/zidovudine qd alone. Median adherence was slightly higher in the QD arm, although both arms had broad variability and overlapping interquartile ranges. Adverse events were infrequent and occurred with similar frequency between arms; treatment-related adverse events were abdominal pain, flatulence, nausea, headache, and abnormal dreams (1 patient [3%] for each adverse event). No patients withdrew due to adverse events, and no abacavir hypersensitivity reactions were reported. Conclusion: In this pilot study of patients suppressed on abacavir/lamivudine/zidovudine bid plus EFV, 94% of participants switching to abacavir/lamivudine/zidovudine qd plus EFV maintained virologic suppression, compared to 89% of participants continuing abacavir/lamivudine/zidovudine bid plus EFV

Anti-Human Immunodeficiency Virus Type 1 Activity of the Nonnucleoside Reverse Transcriptase Inhibitor GW678248 in Combination with Other Antiretrovirals against Clinical Isolate Viruses and In Vitro Selection for Resistance

GW678248, a novel nonnucleoside reverse transcriptase inhibitor, has been evaluated for anti-human immunodeficiency virus activity in a variety of in vitro assays against laboratory strains and clinical isolates. When GW678248 was tested in combination with approved drugs in the nucleoside and nucleotide reverse transcriptase inhibitor classes or the protease inhibitor class, the antiviral activities were either synergistic or additive. When GW678248 was tested in combination with approved drugs in the nonnucleoside reverse transcriptase inhibitor class, the antiviral activities were either additive or slightly antagonistic. Clinical isolates from antiretroviral drug-experienced patients were selected for evaluation of sensitivity to GW678248 in a recombinant virus assay. Efavirenz (EFV) and nevirapine (NVP) had ≥10-fold increases in their 50% inhibitory concentrations (IC(50)s) for 85% and 98% of the 55 selected isolates, respectively, whereas GW678248 had a ≥10-fold increase in the IC(50) for only 17% of these isolates. Thus, 81 to 83% of the EFV- and/or NVP-resistant viruses from this data set were susceptible to GW678248. Virus populations resistant to GW678248 were selected by in vitro dose-escalating serial passage. Resistant progeny viruses recovered after eight passages had amino acid substitutions V106I, E138K, and P236L in the reverse transcriptase-coding region in one passage series and amino acid substitutions K102E, V106A, and P236L in a second passage series

In Vitro Antiviral Activity of the Novel, Tyrosyl-Based Human Immunodeficiency Virus (HIV) Type 1 Protease Inhibitor Brecanavir (GW640385) in Combination with Other Antiretrovirals and against a Panel of Protease Inhibitor-Resistant HIV▿

Brecanavir, a novel tyrosyl-based arylsulfonamide, high-affinity, human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI), has been evaluated for anti-HIV activity in several in vitro assays. Preclinical assessment of brecanavir indicated that this compound potently inhibited HIV-1 in cell culture assays with 50% effective concentrations (EC50s) of 0.2 to 0.53 nM and was equally active against HIV strains utilizing either the CXCR4 or CCR5 coreceptor, as was found with other PIs. The presence of up to 40% human serum decreased the anti-HIV-1 activity of brecanavir by 5.2-fold, but under these conditions the compound retained single-digit nanomolar EC50s. When brecanavir was tested in combination with nucleoside reverse transcriptase inhibitors, the antiviral activity of brecanavir was synergistic with the effects of stavudine and additive to the effects of zidovudine, tenofovir, dideoxycytidine, didanosine, adefovir, abacavir, lamivudine, and emtricitabine. Brecanavir was synergistic with the nonnucleoside reverse transcriptase inhibitor nevirapine or delavirdine and was additive to the effects of efavirenz. In combination with other PIs, brecanavir was additive to the activities of indinavir, lopinavir, nelfinavir, ritonavir, amprenavir, saquinavir, and atazanavir. Clinical HIV isolates from PI-experienced patients were evaluated for sensitivity to brecanavir and other PIs in a recombinant virus assay. Brecanavir had a <5-fold increase in EC50s against 80% of patient isolates tested and had a greater mean in vitro potency than amprenavir, indinavir, lopinavir, atazanavir, tipranavir, and darunavir. Brecanavir is by a substantial margin the most potent and broadly active antiviral agent among the PIs tested in vitro

Antiviral Activity of GW678248, a Novel Benzophenone Nonnucleoside Reverse Transcriptase Inhibitor

The compound GW678248 is a novel benzophenone nonnucleoside reverse transcriptase inhibitor (NNRTI). Preclinical assessment of GW678248 indicates that this compound potently inhibits wild-type (WT) and mutant human immunodeficiency virus type 1 (HIV-1) reverse transcriptase in biochemical assays, with 50% inhibitory concentrations (IC(50)s) between 0.8 and 6.8 nM. In HeLa CD4 MAGI cell culture virus replication assays, GW678248 has an IC(50) of ≤21 nM against HIV-1 isogenic strains with single or double mutations known to be associated with NNRTI resistance, including L100I, K101E, K103N, V106A/I/M, V108I, E138K, Y181C, Y188C, Y188L, G190A/E, P225H, and P236L and various combinations. An IC(50) of 86 nM was obtained with a mutant virus having V106I, E138K, and P236L mutations that resulted from serial passage of WT virus in the presence of GW678248. The presence of 45 mg/ml human serum albumin plus 1 mg/ml α-1 acid glycoprotein increased the IC(50) approximately sevenfold. Cytotoxicity studies with GW678248 indicate that the 50% cytotoxicity concentration is greater than the level of compound solubility and provides a selectivity index of >2,500-fold for WT, Y181C, or K103N HIV-1. This compound exhibits excellent preclinical antiviral properties and, as a prodrug designated GW695634, is being developed as a new generation of NNRTI for the treatment of HIV-1 in combination with other antiretroviral agents

HIV RNA Screening Reduces Integrase Strand Transfer Inhibitor Resistance Risk in Persons Receiving Long-Acting Cabotegravir for HIV Prevention.

BackgroundThe HPTN 083 trial demonstrated that long-acting cabotegravir (CAB-LA) was superior to tenofovir-disoproxil fumarate/emtricitabine for human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP). Integrase strand transfer inhibitor (INSTI) resistance-associated mutations (RAMs) were detected in some participants with HIV infection. We used a low viral load INSTI genotyping assay to evaluate the timing of emergence of INSTI RAMs and assessed whether HIV screening with a sensitive RNA assay would have detected HIV infection before INSTI resistance emerged.MethodsSingle-genome sequencing to detect INSTI RAMs was performed for samples with viral loads &lt;500 copies/mL from 5 participants with previously identified INSTI RAMs and 2 with no prior genotyping results.ResultsMajor INSTI RAMs were detected in all 7 cases. HIV RNA testing identified infection before major INSTI RAMs emerged in 4 cases and before additional major INSTI RAMs accumulated in 1 case. Most INSTI RAMs were detected early when the viral load was low and CAB concentration was high.ConclusionsWhen using CAB-LA PrEP, earlier detection of HIV infection with a sensitive RNA assay may allow for earlier treatment initiation with the potential to reduce INSTI resistance risk. Further studies are needed to evaluate the value and feasibility of HIV RNA testing with CAB-LA PrEP