Effect of Rest Interval Duration on the Volume Completed During a High-Intensity Bench Press Exercise.

ABSTRACT: Hernandez, DJ, Healy, S, Giacomini, ML, and Kwon, YS. Effect of rest interval duration on the volume completed during a high-intensity bench press exercise. J Strength Cond Res 35(11): 2981-2987, 2021-Between-set rest intervals (RIs) are one of the most important variables in resistance training; however, no known research has investigated the effects of RIs greater than 5 minutes during high-intensity strength training. The purpose of this research was to examine the effects of 3 different RIs on repetition sustainability and training volume (sets × reps × resistance) during a high-intensity bench press exercise. Fifteen resistance-trained male subjects (mean ± SD, age = 25.5 ± 4.5 years, and bench press 1 repetition maximum [1RM] ratio [1RM/body mass] = 1.39 ± 0.1) completed 3 experimental sessions, during which 4 sets of the bench press were performed with 85% of 1RM load. Subjects performed the bench press using 3 different RIs in a random counterbalanced design. Data were analyzed using both a one- and two-way analysis of variance with repeated measures. As sets progressed, repetitions were significantly different (p < 0.05) between all RIs, and only the 8-minute RI (p < 0.05) allowed for the complete sustainability of repetitions over 4 consecutive sets. Subjects attained the greatest training volume (p < 0.05) using an 8-minute RI between sets compared with a 2- or 5-minute RI. Similarly, a significantly greater training volume was achieved using the 5-minute RI compared with the 2-minute RI. Resistance-trained men, with the goal of greater volume during strength training, would benefit from longer RIs, specifically using an 8-minute RI between 4 consecutive sets of a bench press exercise.

Gérmenes aislados en pacientes ingresados en la terapia intensiva del Hospital Clínico Quirúrgico Provincial Dr. Joaquín Albarrán / Germs isolated from intensive care patients at Dr. Joaquín Albarrán Provincial Clinical Surgical Hospital

Introducción: Las infecciones asociadas a los cuidados sanitarios en los servicios de atención al paciente crítico se asocian a un alto riesgo de muerte y costos significativos. Objetivo: Identificar los gérmenes más frecuentes en los cultivos y su resistencia a los antimicrobianos en la terapia intensiva del Hospital Clínico Quirúrgico Provincial Dr. Joaquín Albarrán. Métodos: Se realizó un estudio descriptivo, retrospectivo, en la terapia intensiva del Hospital Clínico Quirúrgico Provincial Dr. Joaquín Albarrán, de enero del 2015 a diciembre del 2018, el universo estuvo constituido por 1847 cultivos realizados seleccionándose 654 en los que se obtuvo crecimiento; para el análisis estadístico se utilizó el SPSS 22.0. Resultados: De los gérmenes aislados, la Klebsiella spp fue la más frecuente (31 por ciento), seguida del Staphylococcus spp (24,5 por ciento) y de la E. coli (9,8 por ciento). En los esputos se mantuvo la Klebsiella spp (45,1 por ciento), en los hemocultivos el Staphylococcus spp (53,6 por ciento) y en los urocultivos la Candida (41,1 por ciento), seguida de la E. coli (27 por ciento). De los antimicrobianos usados en terapia para tratar la Klebsiella spp, la E. coli, el Acinetobacter y la pseudomona spp, el más recomendado es la colistina (0-25 por ciento de resistencia) y para el Staphylococcus spp, la vancomicina (1,8 por ciento). Conclusiones: Los gérmenes Gram negativos siguen siendo los más frecuentemente aislados en los cultivos de los pacientes hospitalizados en terapia, con un alto nivel de resistencia para la mayoría de los antibióticos(AU)

Introduction: Infections related to critical care settings are associated to high death risk and significant costs. Objective: Identify the germs most commonly found in cultures and their resistance to antimicrobials in the intensive care service of Dr. Joaquín Albarrán Provincial Clinical Surgical Hospital. Methods: A retrospective descriptive study was conducted at the intensive care service of Dr. Joaquín Albarrán Provincial Clinical Surgical Hospital from January 2015 to December 2018. The study universe was 1 847 cultures, from which 654 were selected in which growth was obtained. Data were processed with the statistical software SPPS 22.0. Results: Of the germs isolated, Klebsiella spp. were the most common (31 percent, followed by Staphylococcus spp. (24.5 percent) and E. coli (9.8 percent). Klebsiella spp. were frequent in sputum cultures (45.1 percent), Staphylococcus spp. in blood cultures (53.6 percent) and Candida in urine cultures (41.1 percent), followed by E. coli (27 percent). Among the antimicrobials used to treat Klebsiella spp., E. coli, Acinetobacter and Pseudomonas spp., the most recommended is colistin (0-25 percent resistance) and vancomycin for Staphylococcus spp. (1.8 percent). Conclusions: Gram-negative germs continue to be the most commonly isolated in cultures from intensive care patients, with a high level of resistance to most antibiotics(AU)

Discovery of the Novel Entecavir-Resistant Hepatitis B Virus Reverse Transcriptase A181C Substitution From an Integrated Genotypic Analysis.

Entecavir (ETV) is a first-line therapy for chronic hepatitis B virus (HBV), demonstrating potent suppression of HBV DNA and a high barrier to viral resistance. Previous studies revealed that ETV-resistant (ETVr) HBV DNA resulted from substitutions in the HBV reverse transcriptase (RT) at positions rtT184, rtS202, or rtM250 in combination with lamivudine resistance (LVDr) substitutions rtM204I/V±rtL180M. In vitro, viral variants exhibit varying degrees of ETV susceptibility and replication capacity depending on specific resistance substitutions. To explore the potential for additional pathways to ETVr, HBV RT sequences from 982 evaluable patients enrolled in 17 ETV clinical studies were analyzed. Thirty novel emergent substitutions at amino acid positions not previously associated with HBV nucleos(t)ide drug resistance were observed in at least 2 patients and were identified in patient-derived HBV with a wild-type, LVDr, or ETVr RT sequence. Phenotypic analysis of these substitutions indicated that they had no effect on ETV susceptibility. Phenotypic analysis was also performed on patient-derived HBV RT sequences from 10 LVD-naive and 13 LVD-experienced patients with virologic breakthrough and emergent novel substitutions while on ETV treatment. One LVD-experienced patient-derived HBV RT harboring LVDr substitutions rtL180M+rtM204V with rtA181C displayed reduced ETV susceptibility (122-fold greater than wild-type HBV) and remained susceptible to adefovir and tenofovir. HBV harboring the rtA181C substitution without LVDr substitutions rtL180M+rtM204V remained susceptible to inhibition by ETV, adefovir, and tenofovir, although cross-resistance to LVD and telbivudine was observed. Conclusion: An integrated genotypic analysis of HBV RT sequences from patients with chronic HBV treated with ETV led to the discovery of the novel ETVr substitution rtA181C. This substitution was always detected in combination with LVDr substitutions rtL180M+rtM204V in ETV-treated patients.

P3-P4 ureas and reverse carbamates as potent HCV NS3 protease inhibitors: Effective transposition of the P4 hydrogen bond donor.

A series of tripeptidic acylsulfonamide inhibitors of HCV NS3 protease were prepared that explored structure-activity relationships (SARs) at the P4 position, and their in vitro and in vivo properties were evaluated. Enhanced potency was observed in a series of P4 ureas; however, the PK profiles of these analogues were less than optimal. In an effort to overcome the PK shortcomings, modifications to the P3-P4 junction were made. This included a strategy in which one of the two urea N-H groups was either N-methylated or replaced with an oxygen atom. The former approach provided a series of regioisomeric N-methylated ureas while the latter gave rise to P4 reverse carbamates, both of which retained potent NS3 inhibitory properties while relying upon an alternative H-bond donor topology. Details of the SARs and PK profiles of these analogues are provided.

Potent Inhibitors of Hepatitis C Virus NS3 Protease: Employment of a Difluoromethyl Group as a Hydrogen-Bond Donor.

The design and synthesis of potent, tripeptidic acylsulfonamide inhibitors of HCV NS3 protease that contain a difluoromethyl cyclopropyl amino acid at P1 are described. A cocrystal structure of 18 with a NS3/4A protease complex suggests the presence of a H-bond between the polarized C-H of the CHF2 moiety and the backbone carbonyl of Leu135 of the enzyme. Structure-activity relationship studies indicate that this H-bond enhances enzyme inhibitory potency by 13- and 17-fold compared to the CH3 and CF3 analogues, respectively, providing insight into the deployment of this unique amino acid.

The discovery and optimization of naphthalene-linked P2-P4 Macrocycles as inhibitors of HCV NS3 protease.

Naphthalene-linked P2-P4 macrocycles within a tri-peptide-based acyl sulfonamide chemotype have been synthesized and found to inhibit HCV NS3 proteases representing genotypes 1a and 1b with single digit nanomolar potency. The pharmacokinetic profile of compounds in this series was optimized through structural modifications along the macrocycle tether as well as the P1 subsite. Ultimately a compound with oral bioavailability of 100% in rat, and a long half-life in plasma was obtained. However, compounds in this macrocyclic series exhibited cardiac effects in an isolated rabbit heart model and for this reason further optimization efforts were discontinued.

Pooled analysis of HCV genotype 1 resistance-associated substitutions in NS5A, NS3 and NS5B pre-and post-treatment with 12 weeks of daclatasvir, asunaprevir and beclabuvir.

BACKGROUND: Daclatasvir (DCV; non-structural [NS]5A inhibitor) plus asunaprevir (ASV; NS3 inhibitor) plus beclabuvir (BCV; non-nucleoside NS5B inhibitor) is an approved regimen for hepatitis C virus (HCV) genotype (GT)-1 treatment in Japan. A comprehensive analysis of pre-treatment and treatment-emergent HCV resistance to this regimen ± ribavirin (RBV) was performed. METHODS: Data were pooled from five Phase 2/3 studies of DCV+ASV+BCV±RBV given for 12 weeks to GT-1a- or GT-1b-infected patients. The prevalence and impact of pre-treatment resistance-associated substitutions (RAS) in NS5A, NS3, and NS5B on sustained virological response (SVR) was assessed, as were emergent RAS and their post-treatment persistence. RESULTS: Baseline NS5A RAS (GT-1a: M28T, Q30H/L/R/S, L31M, Y93C/H; GT-1b: L31I/M, Y93C/H) were present in 5% (26/561) of GT-1a and 16% (85/537) of GT-1b sequences. SVR12 for GT-1b without RBV was 100% (82/82) with RAS and >99% (427/428) without RAS. For GT-1a, SVR12 without RAS was 97% (85/88) with RBV and 92% (410/447) without RBV; SVR12 with RAS was 100% (2/2) with RBV and 54% (13/24) without RBV. Baseline NS3 (at R155 or D168) and NS5B (at P495) RAS were rare (≤1%). Treatment-emergent NS5A RAS (mostly Q30E/H/K/R±Y93H/N) in GT-1a persisted 60 weeks post-treatment, while NS3 RAS (mostly R155K) and NS5B-P495L/S were no longer detected after 48 or 24 weeks, respectively. CONCLUSIONS: DCV+ASV+BCV±RBV was highly efficacious in HCV GT-1 infection, including HCV GT-1b with NS5A RAS. The fitness of treatment-emergent RAS post-treatment was NS5A > NS3 > NS5B; NS3 and NS5B RAS were generally replaced by wild-type sequence within 48 weeks.

Efficacy and safety of daclatasvir plus pegylated-interferon alfa 2a and ribavirin in previously untreated HCV subjects coinfected with HIV and HCV genotype-1: a Phase III, open-label study.

BACKGROUND: Daclatasvir (DCV) is a potent, pangenotypic, hepatitis C virus (HCV) non-structural protein 5A inhibitor with low potential for drug interactions with antiretroviral therapy (ART). We evaluated the safety and efficacy of DCV plus peginterferon alfa-2a/ribavirin (PegIFN/RBV) in HIV-1/HCV genotype-1-coinfected patients. METHODS: AI444043 (NCT01471574), an open-label, Phase III, single-arm, response-guided treatment (RGT) study included 301 patients. They received DCV doses of 30, 60 or 90 mg once daily (depending on concomitant ART), plus weight-based RBV (<75 kg, 1000 mg/day; or ≥75 kg, 1200 mg/day), and once-weekly PegIFN 180 µg, for 24 weeks. If required by RGT, PegIFN/RBV without DCV was extended for an additional 24 weeks of therapy. The primary endpoint was the proportion of patients with sustained virologic response at post-treatment Week 12 (SVR12). RESULTS: Overall, 224 (74%) patients achieved SVR12 and the lower bound of the 95% confidence interval was higher than the historic SVR rate with PegIFN/RBV alone (70 vs. 29%). Most common adverse events (AEs) were fatigue, neutropenia, anemia, asthenia and headache. On-treatment serious AEs occurred in 24/301 (8%) patients; 18/301 (6%) discontinued treatment due to AE. CONCLUSIONS: DCV + PegIFN/RBV led to sustained HCV virologic response in the majority of HIV-1-HCV-coinfected patients, regardless of concomitant ART. HIV control was not compromised and no new safety signals were identified. This study supports DCV use in HIV-1-HCV-coinfected patients, while allowing the vast majority of patients to remain on their existing ART regimen.

Structure-activity relationships of 4-hydroxy-4-biaryl-proline acylsulfonamide tripeptides: A series of potent NS3 protease inhibitors for the treatment of hepatitis C virus.

The design and synthesis of a series of tripeptide acylsulfonamides as potent inhibitors of the HCV NS3/4A serine protease is described. These analogues house a C4 aryl, C4 hydroxy-proline at the S2 position of the tripeptide scaffold. Information relating to structure-activity relationships as well as the pharmacokinetic and cardiovascular profiles of these analogues is provided.

Effect of minor populations of NS5A and NS5B resistance-associated variants on HCV genotype-3 response to daclatasvir plus sofosbuvir, with or without ribavirin.

BACKGROUND: Treatment of hepatitis C virus (HCV) genotype 3 (GT3) is a medical priority. All-oral treatment of HCV GT3 with daclatasvir (DCV) and sofosbuvir (SOF), with or without ribavirin (RBV), is recommended by several treatment guidelines. The impact of HCV minority populations at amino acid positions in NS5A and NS5B associated with drug resistance on response to DCV+SOF±RBV was assessed in SOF-naive and SOF-experienced HCV patients. METHODS: The presence of baseline NS5A or NS5B polymorphisms was assessed in 227 and 167 HCV-GT3-infected patients, respectively, from four clinical studies of DCV+SOF±RBV. Polymorphisms were identified at a sequencing detection threshold of ≥10%, and at ≥1% by next-generation sequencing (NGS) for a subset. RESULTS: No SOF resistance-associated polymorphisms were detected at baseline. Among 58 patients with prospective baseline sequencing data at ≥10% and ≥1%, detectable NS5A substitutions at A30 (A30K/R/S/T/V), S62 (S62A/F/K/L/T) or Y93H were 38% more prevalent at ≥1% compared with ≥10% (55% [32/58] versus 41% [24/58] of patients), although sustained virological response (SVR) in patients with these substitutions remained the same at both sequencing thresholds (88%). Only one additional Y93H was detected at ≥1%; the patient achieved SVR. In two virological failures with baseline Y93H, a minority S62L substitution at baseline was enriched from <20% to ≥95% at failure. Treatment-emergent minority populations (at A30, L31, P32, P58 and E92) observed by NGS in four virological failures became undetectable by week 24 post-treatment. CONCLUSIONS: Sequencing at a depth of ≥10% appears to be sufficient to predict HCV GT3 response to DCV+SOF±RBV.

Characterization of NS5A polymorphisms and their impact on response rates in patients with HCV genotype 2 treated with daclatasvir-based regimens.

OBJECTIVE: Daclatasvir (DCV) is a pan-genotypic non-structural protein 5A (NS5A) inhibitor that is approved for treatment of hepatitis C virus (HCV) genotype (GT)1 and GT3 in the USA and GT1, GT3 and GT4 in Europe. We set out to examine the impact of daclatasvir-based regimens on the sustained virologic response (SVR) in patients with GT2 infection with respect to GT2 subtype and NS5A polymorphisms at amino acid positions associated with daclatasvir resistance. METHODS: Analyses were performed on 283 GT2 NS5A sequences from five daclatasvir regimen-based clinical trials (ClinicalTrials.gov: NCT-01257204, NCT-01359644, NCT-02032875, NCT-02032888 and NCT-01616524) and 143 NS5A sequences from the Los Alamos HCV database. Susceptibility analyses of substitutions at amino acid positions associated with daclatasvir resistance and patient-derived NS5A sequences were performed using an in vitro HCV replication assay. RESULTS: Of 13 GT2 subtypes identified from 426 NS5A sequences, the most prevalent were GT2a (32%), GT2b (48%) and GT2c (10%). The most prevalent NS5A polymorphism was L31M (GT2a = 88%; GT2b = 59%; GT2c = 10%). Substitutions identified in 96% of GT2 NS5A sequences exhibited daclatasvir EC50 values ranging from 0.005 to 20 nM when tested in vitro. A similar range in daclatasvir EC50 values was observed for 16 diverse GT2 patient-derived NS5A sequences (EC50 = 0.005-60 nM). Depending on the daclatasvir-based regimen studied (daclatasvir/interferon-based or daclatasvir/sofosbuvir-based), SVR rates ranged from 90% to 100% in GT2 patients with the most prevalent baseline NS5A-L31M polymorphism, compared with from 96% to 100% without this polymorphism. CONCLUSIONS: High SVR rates were achieved in patients infected with GT2 treated with daclatasvir-based regimens irrespective of GT2 subtype or baseline NS5A polymorphisms.

Discovery of a Potent Acyclic, Tripeptidic, Acyl Sulfonamide Inhibitor of Hepatitis C Virus NS3 Protease as a Back-up to Asunaprevir with the Potential for Once-Daily Dosing.

The discovery of a back-up to the hepatitis C virus NS3 protease inhibitor asunaprevir (2) is described. The objective of this work was the identification of a drug with antiviral properties and toxicology parameters similar to 2, but with a preclinical pharmacokinetic (PK) profile that was predictive of once-daily dosing. Critical to this discovery process was the employment of an ex vivo cardiovascular (CV) model which served to identify compounds that, like 2, were free of the CV liabilities that resulted in the discontinuation of BMS-605339 (1) from clinical trials. Structure-activity relationships (SARs) at each of the structural subsites in 2 were explored with substantial improvement in PK through modifications at the P1 site, while potency gains were found with small, but rationally designed structural changes to P4. Additional modifications at P3 were required to optimize the CV profile, and these combined SARs led to the discovery of BMS-890068 (29).

Impact of Pre-existing NS5A-L31 or -Y93H Minor Variants on Response Rates in Patients Infected with HCV Genotype-1b Treated with Daclatasvir/Asunaprevir.

INTRODUCTION: The combination of daclatasvir (DCV, pan-genotypic NS5A inhibitor) plus asunaprevir (ASV; NS3 protease inhibitor) is approved in Japan, Korea and other countries for the treatment of chronic hepatitis C virus (HCV) genotype (GT)-1. A high (~90 to 100%) sustained virologic response (SVR) with DCV/ASV therapy has been achieved by excluding patients infected with HCV GT-1b with baseline NS5A resistance-associated variants (RAVs) at L31 or Y93H detected by direct sequencing (DS). We set out to determine whether patients with minor variants at NS5A-L31 or -Y93H, detected by next-generation sequencing (NGS), impacted SVR rates with DCV/ASV therapy. METHODS: Baseline samples from 222 interferon (IFN)-ineligible/intolerant (N = 135) and prior non-responder (N = 87) patients infected with GT-1b who were treated with DCV/ASV for 24 weeks in the Phase 3 clinical study AI447026 were prepared for NGS (Ion-Torrent platform). The prevalence of baseline NS5A RAVs and their impact on SVR when observed at ≥1% by NGS in a patient's virus population were examined. NGS and DS (sensitivity ≥20%) data were compared. RESULTS: The prevalence of baseline NS5A RAVs at L31 or Y93H was 29% (63/219) and 18% (39/214) by NGS and DS, respectively. SVR24 rates were comparable in patients without observed baseline L31 or Y93H polymorphisms whether assessed by NGS (96%; 148/154) or by the less sensitive DS platform (95%; 164/173). CONCLUSION: Optimal SVR rates (≥95%) to DCV/ASV treatment were achieved using DS to exclude patients infected with GT-1b with NS5A RAVs at L31 or Y93H representing ≥20% of their virus population. Exclusion by NGS of patients with minor variants in NS5A (<20%) did not enhance SVR rates. These results suggest that the presence of minor variants in NS5A does not appear to impact the overall SVR rate in patients with GT-1b treated with DCV/ASV. FUNDING: This study was sponsored by Bristol-Myers Squibb. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01497834.

NS5A Sequence Heterogeneity and Mechanisms of Daclatasvir Resistance in Hepatitis C Virus Genotype 4 Infection.

BACKGROUND: Daclatasvir is an NS5A inhibitor approved for treatment of infection due to hepatitis C virus (HCV) genotypes (GTs) 1-4. To support daclatasvir use in HCV genotype 4 infection, we examined a diverse genotype 4-infected population for HCV genotype 4 subtype prevalence, NS5A polymorphisms at residues associated with daclatasvir resistance (positions 28, 30, 31, or 93), and their effects on daclatasvir activity in vitro and clinically. METHODS: We performed phylogenetic analysis of genotype 4 NS5A sequences from 186 clinical trial patients and 43 sequences from the European HCV database, and susceptibility analyses of NS5A polymorphisms and patient-derived NS5A sequences by using genotype 4 NS5A hybrid genotype 2a replicons. RESULTS: The clinical trial patients represented 14 genotype 4 subtypes; most prevalent were genotype 4a (55%) and genotype 4d (27%). Daclatasvir 50% effective concentrations for 10 patient-derived NS5A sequences representing diverse phylogenetic clusters were ≤0.080 nM. Most baseline sequences had ≥1 NS5A polymorphism at residues associated with daclatasvir resistance; however, only 3 patients (1.6%) had polymorphisms conferring ≥1000-fold daclatasvir resistance in vitro. Among 46 patients enrolled in daclatasvir trials, all 20 with baseline resistance polymorphisms achieved a sustained virologic response. CONCLUSIONS: Circulating genotype 4 subtypes are genetically diverse. Polymorphisms conferring high-level daclatasvir resistance in vitro are uncommon before therapy, and clinical data suggest that genotype 4 subtype and baseline polymorphisms have minimal impact on responses to daclatasvir-containing regimens.

High Sustained Virologic Response to Daclatasvir Plus Asunaprevir in Elderly and Cirrhotic Patients with Hepatitis C Virus Genotype 1b Without Baseline NS5A Polymorphisms.

INTRODUCTION: Oral daclatasvir (DCV; pangenotypic NS5A inhibitor) plus asunaprevir (ASV; NS3 protease inhibitor) is approved in Japan and Korea for treatment of chronic hepatitis C virus (HCV) genotype 1. Response to DCV + ASV is affected by DCV resistance-associated polymorphisms (RAPs) in HCV NS5A. The prevalence and influence of these RAPs on 12-week sustained virologic response (SVR12) to DCV + ASV was evaluated in Asian and non-Asian patients. METHODS: Data were pooled from 5 national and international studies of patients with HCV genotype 1b (GT-1b) receiving DCV + ASV at their recommended doses. Baseline NS5A RAPs and their effect on SVR12 were assessed overall, in older (≥65 years) patients, patients with cirrhosis, and in patients stratified by baseline HCV RNA or prior treatment experience with interferon-based therapy. RESULTS: Baseline NS5A sequences were available from 988 patients (374 Japanese; 125 Korean/Taiwanese; 489 from non-Asian countries), 979 of whom were assessed for SVR12. Pretreatment NS5A-L31F/I/M/V and/or NS5A-Y93H polymorphisms were present in 18% of Japanese and 12-13% of non-Japanese patients; these RAPs reduced SVR12 by 54.9% overall (93.9% [787/838] SVR12 when absent, 39.0% [55/141] SVR12 when present), with comparable reductions observed in Asians and non-Asians and across all categories of treatment experience, age, and cirrhosis. RAP-associated SVR12 rates declined with increasing baseline HCV RNA (SVR12 with RAPs: 64.7% [11/17] at 5-6 log10 IU/mL, 29.8% [14/47] at 7-8 log10). Without baseline RAPs, very high SVR12 rates (92-100%) were observed in older patients and patients with cirrhosis irrespective of national origin, with similarly high rates observed among treatment-naïve and interferon-experienced patients and those with high baseline HCV RNA. CONCLUSIONS: Following DCV + ASV treatment, the SVR12 rates in GT-1b patients without baseline NS5A-L31F/I/M/V and/or NS5A-Y93H polymorphisms were very high (approximately 90-100%), irrespective of age, cirrhosis, prior interferon treatment, or baseline HCV RNA. FUNDING: Bristol-Myers Squibb.

Daclatasvir plus peginterferon alfa and ribavirin for treatment-naive chronic hepatitis C genotype 1 or 4 infection: a randomised study.

OBJECTIVE: To evaluate the safety and efficacy of daclatasvir, an HCV NS5A inhibitor with pangenotypic activity, administered with peginterferon-alfa-2a/ribavirin. DESIGN: In this Phase 2b double-blind, placebo-controlled study, treatment-naive adults with HCV genotype 1 (N=365) or 4 (N=30) infection were randomly assigned (2:2:1) to daclatasvir 20 mg or 60 mg, or placebo once daily plus weekly peginterferon-alfa-2a and twice-daily ribavirin. Daclatasvir recipients achieving protocol-defined response (PDR; HCV-RNA

Daclatasvir plus peginterferon and ribavirin is noninferior to peginterferon and ribavirin alone, and reduces the duration of treatment for HCV genotype 2 or 3 infection.

BACKGROUND & AIMS: Twenty-four weeks of treatment with peginterferon and ribavirin for chronic hepatitis C virus (HCV) genotype 2 or 3 infection produces a sustained virologic response (SVR) in 70%-80% of patients. We performed a randomized, double-blind, phase 2b study to assess whether adding daclatasvir, a nonstructural protein 5A (NS5A) inhibitor that is active against these genotypes, improves efficacy and shortens therapy. METHODS: Patients with HCV genotype 2 or 3 infection (n = 151), enrolled at research centers in North America, Europe, or Australia, were assigned randomly to groups given 12 or 16 weeks of daclatasvir (60 mg once daily), or 24 weeks of placebo, each combined with peginterferon alfa-2a and ribavirin. Treatment was extended to 24 weeks for recipients of daclatasvir who did not meet the criteria for early virologic response. The primary end point was SVR at 24 weeks after treatment (SVR24). RESULTS: Baseline characteristics were similar among patients within each HCV genotype group. However, the 80 patients with HCV genotype 3, compared with the 71 patients with HCV genotype 2, were younger (mean age, 45 vs 53 y, respectively), and a larger proportion had cirrhosis (23% vs 1%, respectively). Among patients with HCV genotype 2 infection, an SVR24 was achieved by 83%, 83%, and 63% of those in the daclatasvir 12-week group, the daclatasvir 16-week group, or the placebo group, respectively; among patients with HCV genotype 3 infection, an SVR24 was achieved by 69%, 67%, and 59% of patients in these groups, respectively. Differences between genotypes largely were attributable to the higher frequency of post-treatment relapse among patients infected with HCV genotype 3. In both daclatasvir arms for both HCV genotypes, the lower bound of the 80% confidence interval of the difference in SVR24 rates between the daclatasvir and placebo arms was above -20%, establishing noninferiority. Safety findings were similar among groups, and were typical of those expected from peginterferon alfa and ribavirin therapy. CONCLUSIONS: Twelve or 16 weeks of treatment with daclatasvir, in combination with peginterferon alfa-2a and ribavirin, is a well tolerated and effective therapy for patients with HCV genotype 2 or 3 infections. Daclatasvir-containing regimens could reduce the duration of therapy for these patients. Clinicaltrials.gov number: NCT01257204.

Randomized trial of asunaprevir plus peginterferon alfa and ribavirin for previously untreated genotype 1 or 4 chronic hepatitis C.

BACKGROUND & AIMS: Asunaprevir is a selective HCV NS3 protease inhibitor, active against genotypes 1, 4, 5, and 6 in vitro. We evaluated asunaprevir plus peginterferon alfa-2a/ribavirin (PegIFNα/RBV) for genotype 1 and 4 chronic HCV. METHODS: In this phase 2b, double-blind, placebo-controlled study, treatment-naive adults with genotype 1 (n=213) or 4 (n=25) were randomly assigned (3:1) to asunaprevir 200mg or placebo twice daily plus PegIFNα/RBV. Asunaprevir recipients, achieving protocol-defined response (HCV-RNA below quantification limit at week 4 and undetectable at week 10), were rerandomized at week 12 to continue asunaprevir-based triple therapy or receive placebo plus PegIFNα/RBV for weeks 13-24. Patients without protocol-defined response (PDR) and placebo recipients continued PegIFNα/RBV through week 48. Co-primary end points were undetectable HCV-RNA at week 4 and 12 (eRVR) and 24 weeks posttreatment (SVR24). RESULTS: Most patients were male (64.3%), white (83.6%), and had non-CC IL28B genotypes (71.3%). Among genotype 1 patients, eRVR rates (asunaprevir vs. placebo) were 67% (80% CI 62, 72) vs. 6% (80% CI 2, 10); corresponding SVR24 rates were 64% (80% CI 59, 68) vs. 44% (80% CI 36, 53). SVR24 among genotype 4 patients was 89% (asunaprevir) vs. 43% (placebo). Rates of rash and haematologic adverse events were similar between treatment groups. Five asunaprevir-treated patients had grade 4 alanine aminotransferase elevations that resolved following discontinuation (n=4) or with continued dosing (n=1). CONCLUSIONS: Addition of asunaprevir to PegIFNα/RBV in treatment-naive genotype 1- or 4-infected patients improves response rates and is well tolerated, with aminotransferase elevations that were manageable with appropriate monitoring. ClinicalTrials.gov ID: NCT01030432.

The discovery of asunaprevir (BMS-650032), an orally efficacious NS3 protease inhibitor for the treatment of hepatitis C virus infection.

The discovery of asunaprevir (BMS-650032, 24) is described. This tripeptidic acylsulfonamide inhibitor of the NS3/4A enzyme is currently in phase III clinical trials for the treatment of hepatitis C virus infection. The discovery of 24 was enabled by employing an isolated rabbit heart model to screen for the cardiovascular (CV) liabilities (changes to HR and SNRT) that were responsible for the discontinuation of an earlier lead from this chemical series, BMS-605339 (1), from clinical trials. The structure-activity relationships (SARs) developed with respect to CV effects established that small structural changes to the P2* subsite of the molecule had a significant impact on the CV profile of a given compound. The antiviral activity, preclincial PK profile, and toxicology studies in rat and dog supported clinical development of BMS-650032 (24).

Discovery and early clinical evaluation of BMS-605339, a potent and orally efficacious tripeptidic acylsulfonamide NS3 protease inhibitor for the treatment of hepatitis C virus infection.

The discovery of BMS-605339 (35), a tripeptidic inhibitor of the NS3/4A enzyme, is described. This compound incorporates a cyclopropylacylsulfonamide moiety that was designed to improve the potency of carboxylic acid prototypes through the introduction of favorable nonbonding interactions within the S1' site of the protease. The identification of 35 was enabled through the optimization and balance of critical properties including potency and pharmacokinetics (PK). This was achieved through modulation of the P2* subsite of the inhibitor which identified the isoquinoline ring system as a key template for improving PK properties with further optimization achieved through functionalization. A methoxy moiety at the C6 position of this isoquinoline ring system proved to be optimal with respect to potency and PK, thus providing the clinical compound 35 which demonstrated antiviral activity in HCV-infected patients.