APOBEC mutagenesis, kataegis, chromothripsis in EGFR-mutant osimertinib-resistant lung adenocarcinomas.

BACKGROUND: Studies of targeted therapy resistance in lung cancer have primarily focused on single-gene alterations. Based on prior work implicating apolipoprotein b mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) mutagenesis in histological transformation of epidermal growth factor receptor (EGFR)-mutant lung cancers, we hypothesized that mutational signature analysis may help elucidate acquired resistance to targeted therapies. PATIENTS AND METHODS: APOBEC mutational signatures derived from an Food and Drug Administration-cleared multigene panel [Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT)] using the Signature Multivariate Analysis (SigMA) algorithm were validated against the gold standard of mutational signatures derived from whole-exome sequencing. Mutational signatures were decomposed in 3276 unique lung adenocarcinomas (LUADs), including 93 paired osimertinib-naïve and -resistant EGFR-mutant tumors. Associations between APOBEC and mechanisms of resistance to osimertinib were investigated. Whole-genome sequencing was carried out on available EGFR-mutant lung cancer samples (10 paired, 17 unpaired) to investigate large-scale genomic alterations potentially contributing to osimertinib resistance. RESULTS: APOBEC mutational signatures were more frequent in receptor tyrosine kinase (RTK)-driven lung cancers (EGFR, ALK, RET, and ROS1; 25%) compared to LUADs at large (20%, P < 0.001); across all subtypes, APOBEC mutational signatures were enriched in subclonal mutations (P < 0.001). In EGFR-mutant lung cancers, osimertinib-resistant samples more frequently displayed an APOBEC-dominant mutational signature compared to osimertinib-naïve samples (28% versus 14%, P = 0.03). Specifically, mutations detected in osimertinib-resistant tumors but not in pre-treatment samples significantly more frequently displayed an APOBEC-dominant mutational signature (44% versus 23%, P < 0.001). EGFR-mutant samples with APOBEC-dominant signatures had enrichment of large-scale genomic rearrangements (P = 0.01) and kataegis (P = 0.03) in areas of APOBEC mutagenesis. CONCLUSIONS: APOBEC mutational signatures are frequent in RTK-driven LUADs and increase under the selective pressure of osimertinib in EGFR-mutant lung cancer. APOBEC mutational signature enrichment in subclonal mutations, private mutations acquired after osimertinib treatment, and areas of large-scale genomic rearrangements highlights a potentially fundamental role for APOBEC mutagenesis in the development of resistance to targeted therapies, which may be potentially exploited to overcome such resistance.

The association between oil spill cleanup-related total hydrocarbon exposure and diabetes.

BACKGROUND: Although evidence suggests relationships between some crude oil components and glycemic dysregulation, no studies have examined oil spill-related chemical exposures in relation to type 2 diabetes mellitus (DM) risk. This study examined the relationship between total hydrocarbon (THC) exposure among workers involved in the 2010 Deepwater Horizon (DWH) oil spill and risk of DM up to 6 years afterward. METHODS: Participants comprised 2660 oil-spill cleanup or response workers in the prospective GuLF Study who completed a clinical exam and had no self-reported DM diagnosis prior to the spill. Maximum THC exposure was estimated with a job-exposure matrix based on interview data and personal measurements taken during cleanup operations. We defined incident DM by self-reported physician diagnosis of DM, antidiabetic medication use, or a measured hemoglobin A1c value ≥ 6.5%. We used log binomial regression to estimate risk ratios (RRs) for DM across ordinal categories of THC exposure. The fully adjusted model controlled for age, sex, race/ethnicity, education, employment status, and health insurance status. We also stratified on clinical body mass index categories. RESULTS: We observed an exposure-response relationship between maximum daily ordinal THC exposure level and incident DM, especially among overweight participants. RRs among overweight participants were 0.99 (95% CI: 0.37, 2.69), 1.46 (95% CI: 0.54, 3.92), and 2.11 (95% CI: 0.78, 5.74) for exposure categories 0.30-0.99 ppm, 1.00-2.99 ppm, and ≥3.00 ppm, respectively (ptrend = 0.03). CONCLUSION: We observed suggestively increasing DM risk with increasing THC exposure level among overweight participants, but not among normal weight or obese participants.

OPTN/SRTR 2016 Annual Data Report: Pancreas.

The number of pancreas transplants performed in the United States increased by 7.0% in 2016 over the previous year, the first such increase in more than a decade, largely attributable to an increase in simultaneous kidney pancreas transplants. Transplant rates increased in 2016, and mortality on the waiting list decreased. The declining enthusiasm for pancreas after kidney (PAK) transplants persisted. The uniform definition of graft failure was approved by the OPTN Board of Directors in 2015 and will be implemented in early 2018. Meanwhile, SRTR continues to refrain from reporting pancreas graft failure data. The OPTN/UNOS Pancreas Transplantation Committee is seeking to broaden allocation of pancreata across compatible ABO blood types in a proposal out for public comment July 31 to October 2, 2017. A new initiative to provide guidance on the benefits of PAK transplants is also out for public comment.

OPTN/SRTR 2015 Annual Data Report: Pancreas.

The number of pancreas transplants performed in the United States stabilized over the last 3 years after nearly a decade of steady decline. Numbers of new additions to the list also stabilized during the same period. Notably, the persistent decline in pancreas after kidney transplants also seems to have abated, at least for now. The first full year of data after implementation of the new pancreas allocation system revealed no change in the distribution of organs between simultaneous pancreas-kidney (SPK) transplant and pancreas transplant alone. The percentage of kidneys used in SPK transplants was also unchanged. While a uniform definition of pancreas graft failure was approved in June 2015, it is awaiting implementation. Meanwhile, SRTR will refrain from publishing pancreas graft failure data in the program-specific reports. Therefore, it is difficult to track trends in outcomes after pancreas transplant over the past 2 years. New initiatives by the OPTN/UNOS Pancreas Transplantation Committee include facilitated pancreas allocation and broadened allocation of pancreata across compatible ABO blood types to increase organ utilization.

The American Society of Transplantation Consensus Conference on the Use of Hepatitis C Viremic Donors in Solid Organ Transplantation.

The availability of direct-acting antiviral agents for the treatment of hepatitis C virus (HCV) infection has resulted in a profound shift in the approach to the management of this infection. These changes have affected the practice of solid organ transplantation by altering the framework by which patients with end-stage organ disease are managed and receive organ transplants. The high level of safety and efficacy of these medications in patients with chronic HCV infection provides the opportunity to explore their use in the setting of transplanting organs from HCV-viremic patients into non-HCV-viremic recipients. Because these organs are frequently discarded and typically come from younger donors, this approach has the potential to save lives on the solid organ transplant waitlist. Therefore, an urgent need exists for prospective research protocols that study the risk versus benefit of using organs for hepatitis C-infected donors. In response to this rapidly changing practice and the need for scientific study and consensus, the American Society of Transplantation convened a meeting of experts to review current data and develop the framework for the study of using HCV viremic organs in solid organ transplantation.

No one size fits all-Shortening duration of therapy with direct-acting antivirals for hepatitis C genotype 1 infection.

The advent of shorter duration, highly effective and well-tolerated interferon-free therapy now provides an opportunity for virtually all HCV-infected individuals to be cured. However, there continues to be a need to simplify and shorten treatment duration. Shortening therapy to 8 weeks with sofosbuvir and ledipasvir can be considered in treatment patients with HCV genotype 1 infection and low baseline viral load. A number of other 8-week dual and triple therapy direct-acting antiviral (DAA) regimens are in advanced clinical development. Several small studies have further demonstrated the feasibility of 6 weeks of sofosbuvir therapy in combination with an NS5A inhibitor and a protease inhibitor for HCV genotype 1. Four weeks of therapy with various combinations of the currently available DAAs appears to be suboptimal with poor response rates observed in phase 2 trials. Response-guided therapy is another promising tool that may allow for shorter therapy but require further research. Shortening therapy and retreating relapsers may be a viable cost-saving measure, but requires further cost-benefit analysis and more data on the impact of resistance on retreatment options.

Prevention of allograft HCV recurrence with peri-transplant human monoclonal antibody MBL-HCV1 combined with a single oral direct-acting antiviral: A proof-of-concept study.

Patients with active hepatitis C virus (HCV) infection at transplantation experience rapid allograft infection, increased risk of graft failure and accelerated fibrosis. MBL-HCV1, a neutralizing human monoclonal antibody (mAb) targeting the HCV envelope, was combined with a licensed oral direct-acting antiviral (DAA) to prevent HCV recurrence post-transplant in an open-label exploratory efficacy trial. Eight subjects received MBL-HCV1 beginning on the day of transplant with telaprevir initiated between days 3 and 7 post-transplantation. Following FDA approval of sofosbuvir, two subjects received MBL-HCV1 starting on the day of transplant with sofosbuvir initiated on day 3. Combination treatment was administered for 8-12 weeks or until the stopping rule for viral rebound was met. The primary endpoint was undetectable HCV RNA at day 56 with exploratory endpoints of sustained virologic response (SVR) at 12 and 24 weeks post-treatment. Both subjects receiving mAb and sofosbuvir achieved SVR24. Four of eight subjects in the mAb and telaprevir group met the primary endpoint; one subject achieved SVR24 and three subjects relapsed 2-12 weeks post-treatment. The other four subjects experienced viral breakthrough. There were no serious adverse events related to study treatment. This proof-of-concept study demonstrates that peri-transplant immunoprophylaxis combined with a single oral direct-acting antiviral in the immediate post-transplant period can prevent HCV recurrence.

Real-world effectiveness for 12 weeks of ledipasvir-sofosbuvir for genotype 1 hepatitis C: the Trio Health study.

Early data regarding the "real-world" experience with novel therapies for hepatitis C (HCV) are encouraging. Data are still limited, however, regarding real-world rates of sustained virologic response (SVR) for ledipasvir-sofosbuvir (LDV-SOF), particularly for patients with prior treatment failure. We performed a retrospective cohort study of 1597 patients with chronic genotype 1 HCV who were treated using 12 weeks of the following regimens LDV-SOF±ribavirin (RBV) (n=1521 without RBV, n=76 with RBV). The primary outcome was SVR-determined at 12 weeks in an intention-to-treat design. Prescription according to Food and Drug Administration (FDA) approved labelling (adding RBV for patients with cirrhosis and treatment failure) was assessed in multivariate models. The study population was aged 60 years on average (range 19-89), 60% male, 50% Caucasian, 43% cared for at an academic centre and 30% cirrhotic. Overall, LDV-SOF resulted in a 94% SVR rate. Only 44 (2.9%) patients relapsed. LDV-SOF+RBV yielded SVR in 97% with 0 viral relapses. While cirrhosis and thrombocytopenia were associated with lower odds of SVR, in a multivariable regression model, only treatment at an academic centre and prescriptions contrary to FDA labelling were significantly associated with lower SVR-odds ratios, 0.56 95% CI (0.35-0.87) and 0.29 95% CI(0.12-0.68), respectively. The real-world experience with LDV-SOF mirrors the SVR rates observed in clinical trials. Efforts to promote prescription within FDA recommendations are warranted.

Effect of viral suppression on hepatic venous pressure gradient in hepatitis C with cirrhosis and portal hypertension.

Portal hypertension is a predictor of liver-related clinical events and mortality in patients with hepatitis C and cirrhosis. The effect of interferon-free hepatitis C treatment on portal pressure is unknown. Fifty patients with Child-Pugh-Turcotte (CPT) A and B cirrhosis and portal hypertension (hepatic venous pressure gradient [HVPG] >6 mm Hg) were randomized to receive 48 weeks of open-label sofosbuvir plus ribavirin at Day 1 or after a 24-week observation period. The primary endpoint was sustained virologic response 12 weeks after therapy (SVR12) in patients who received ≥1 dose of treatment. Secondary endpoints included changes in HVPG, laboratory parameters, and MELD and CPT scores. A subset of patients was followed 48 weeks posttreatment to determine late changes in HVPG. SVR12 occurred in 72% of patients (33/46). In the 37 patients with paired HVPG measurements at baseline and the end of treatment, mean HVPG decreased by -1.0 (SD 3.97) mm Hg. Nine patients (24%) had ≥20% decreases in HVPG during treatment. Among 39 patients with pretreatment HVPG ≥12 mm Hg, 27 (69%) achieved SVR12. Four of the 33 (12%) patients with baseline HVPG ≥12 mm Hg had HVPG <12 mm Hg at the end of treatment. Of nine patients with pretreatment HVPG ≥12 mm Hg who achieved SVR12 and completed 48 weeks of follow-up, eight (89%) had a ≥20% reduction in HVPG, and three reduced their pressure to <12 mm Hg. Patients with chronic HCV and compensated or decompensated cirrhosis who achieve SVR can have clinically meaningful reductions in HVPG at long-term follow-up. (EudraCT 2012-002457-29).

Multiple endosymbiont infections and reproductive manipulations in a linyphiid spider population.

In many arthropods, maternally inherited endosymbiotic bacteria can increase infection frequency by manipulating host reproduction. Multiple infections of different bacteria in a single host population are common, yet few studies have documented concurrent endosymbiont phenotypes or explored their potential interactions. We hypothesized that spiders might be a particularly useful taxon for investigating endosymbiont interactions, because they are host to a plethora of endosymbiotic bacteria and frequently exhibit multiple infections. We established two matrilines from the same population of the linyphiid spider Mermessus fradeorum and then used antibiotic curing and controlled mating assays to demonstrate that each matriline was subject to a distinct endosymbiotic reproductive manipulation. One matriline was co-infected with Rickettsia and Wolbachia and produced offspring with a radical female bias. Antibiotic treatment eliminated both endosymbionts and restored an even sex ratio to subsequent generations. Chromosomal and fecundity observations suggest a feminization mechanism. In the other matriline, a separate factorial mating assay of cured and infected spiders demonstrated strong cytoplasmic incompatibility (CI) induced by a different strain of Wolbachia. However, males with this Wolbachia induced only mild CI when mated with the Rickettsia-Wolbachia females. In a subsequent survey of a field population of M. fradeorum, we detected these same three endosymbionts infecting 55% of the spiders in almost all possible combinations, with nearly half of the infected spiders exhibiting multiple infection. Our results suggest that a dynamic network of endosymbionts may interact both within multiply infected hosts and within a population subject to multiple strong reproductive manipulations.

Peginterferon and ribavirin for treatment of recurrent hepatitis C disease in HCV-HIV coinfected liver transplant recipients.

Achievement of a sustained virologic response (SVR) with antiviral therapy significantly improves graft survival in hepatitis C virus (HCV) monoinfected liver transplant (LT) patients. Risks and benefits of HCV therapy in HCV-human immunodeficiency virus (HIV) coinfected LT recipients are not well established. Among 89 HCV-HIV LT recipients in the HIVTR cohort, 39 (23% Black, 79% genotype 1, 83% fibrosis stage ≤ 1) were treated with peginterferon-a2a or a2b plus ribavirin for a median 363 days (14-1373). On intent-to-treat basis, 22% (95% CI: 10-39) and 14% (95% CI: 5-30) achieved an end-of-treatment response (EOTR) and SVR, respectively. By per-protocol analysis (completed 48 weeks of therapy ± dose reductions), 42% and 26% had EOTR and SVR, respectively. Severe adverse events occurred in 85%, with 26% hospitalized with infections and 13% developing acute rejection. Early discontinuations and dose reductions occurred in 38% and 82%, respectively, despite use of growth factors in 85%. Eighteen of 39 treated patients (46%) subsequently died/had graft loss, with 10 (26%) attributed to recurrent HCV. In conclusion, SVR rates are low and tolerability is poor in HCV-HIV coinfected transplant recipients treated with peginterferon and ribavirin. These results highlight the critical need for better tolerated and more efficacious HCV therapies for HCV-HIV coinfected transplant recipients.

Human monoclonal antibody MBL-HCV1 delays HCV viral rebound following liver transplantation: a randomized controlled study.

Rapid allograft infection complicates liver transplantation (LT) in patients with hepatitis C virus (HCV). Pegylated interferon-α and ribavirin therapy after LT has significant toxicity and limited efficacy. The effect of a human monoclonal antibody targeting the HCV E2 glycoprotein (MBL-HCV1) on viral clearance was examined in a randomized, double-blind, placebo-controlled pilot study in patients infected with HCV genotype 1a undergoing LT. Subjects received 11 infusions of 50 mg/kg MBL-HCV1 (n=6) or placebo (n=5) intravenously with three infusions on day of transplant, a single infusion on days 1 through 7 and one infusion on day 14 after LT. MBL-HCV1 was well-tolerated and reduced viral load for a period ranging from 7 to 28 days. Median change in viral load (log10 IU/mL) from baseline was significantly greater (p=0.02) for the antibody-treated group (range -3.07 to -3.34) compared to placebo group (range -0.331 to -1.01) on days 3 through 6 posttransplant. MBL-HCV1 treatment significantly delayed median time to viral rebound compared to placebo treatment (18.7 days vs. 2.4 days, p<0.001). As with other HCV monotherapies, antibody-treated subjects had resistance-associated variants at the time of viral rebound. A combination study of MBL-HCV1 with a direct-acting antiviral is underway.

Transient elastography for predicting clinical outcomes in patients with chronic liver disease.

There is increasing interest in developing noninvasive means to evaluate liver fibrosis in patients with chronic liver disease to determine disease severity, prognosis and optimal treatment. Transient elastography (TE) has previously been demonstrated to predict the presence or absence of advanced fibrosis. The current study was conducted to determine whether TE can identify patients with chronic liver disease at risk of clinical decompensation. A total of 667 patients underwent TE and were followed for a median of 861 days and 57 patients achieved the primary outcome, a composite of clinical endpoints including death, ascites, encephalopathy, increased Child Score ≥ 2, variceal bleed, hepatocellular carcinoma or listing for transplant. Overall, TE had an area under the receiver operating characteristic curve of 0.87 for predicting clinical outcome. Using a cut-off of 10.5 kPa, TE has a sensitivity, specificity, positive predictive value and negative predictive value (NPV) of 94.7%, 63.0%, 19.3% and 99.2%, respectively. A predictive model for clinical events was developed using generalized cross-validation for clinical endpoints considering TE, liver biopsy results and multiple other predictors. Individually, TE performed better than biopsy, or any other variable, for predicting clinical outcome [Harrell's C Statistic 0.86 for TE, 0.78 for stage]. Patients with a TE score of >12.5 kPa were found to have a relative hazard for clinical event of 18.99 compared with patients with TE score <10.5. A combined variable model including TE, aspartate aminotransferase/alanine aminotransferase ratio and model for end-stage liver disease (MELD) yielded the highest predictive accuracy with Harrell's C value of 0.93. In the subset of patients with cirrhosis, TE was not found to be independently associated with clinical outcomes in univariate or multivariate analysis although it retained a high sensitivity and NPV of 97.5% and 92.3%, respectively, at a kPa cut-off of 10.5. TE can successfully identify patients with chronic liver disease who are at low risk of clinical decompensation over a time period of 2 years.

Patients' willingness to accept expanded criteria donor liver transplantation.

Utilization of livers from expanded criteria donors (ECD) is one strategy to overcome the severe organ shortage. The decision to utilize an ECD liver is complex and fraught with uncertainty for both providers and patients. We assessed patients' willingness to accept ECD liver transplantation (LTx) and acceptable 1-year mortality risk. One hundred eight patients listed for LTx were asked to rate their willingness to accept ECD LTx and the associated 1-year mortality risk they were willing to accept. Also, patients completed the SF-36v2 and sociodemographic and health information was gathered from their medical records. Patients reported significantly higher willingness to accept standard criteria donor (SCD) versus ECD LTx (t = 13.8, p < 0.001), with more than one-third of patients reporting low willingness to accept ECD LTx. Relative to our center's 10% SCD LTx 1-year mortality rate, most patients (71%) were willing to accept moderately or substantially higher 1-year mortality risk for ECD LTx. In multivariable analyses, higher lab MELD score and white race were significant independent predictors of both ECD willingness and ECD increased mortality risk acceptability. Findings highlight the importance of assessing patients' willingness to pursue ECD LTx and the relative mortality risks they are willing to accept.

The optimal cut-off for predicting large oesophageal varices using transient elastography is disease specific.

The diagnosis of cirrhosis requires screening for oesophageal varices by upper gastrointestinal endoscopy. In many countries, serological tests and elastography are replacing liver biopsy for diagnosing cirrhosis. The aims of this study were to see whether there was an optimal cut-off of liver stiffness that could predict the presence of large (>F2) oesophageal varices and whether this was disease specific. A total of two hundred and twenty-two patients with all cause cirrhosis (Child class A) were screened, and 211 had successful elastography and are included in the analysis. Of the patients studied, one hundred and thirty-two patients had no or small F1 varices and 79 had large varices. Liver stiffness of 19.8 kPa had a negative predictive value of 91% and a positive predictive value of 55% with an area under the curve (AUC) on receiver operating characteristics (ROC) of 0.73 in differentiating between small and large varices. Seven patients with large varices would have been incorrectly classified. In the 157 patients with hepatitis C as the aetiology of cirrhosis, the negative predictive value was 98% and only one patient was misclassified. Liver stiffness was superior in diagnostic accuracy to platelet count in all patients. A liver stiffness of >19.8 kPa could be utilized as a cut-off for endoscopy and beta blocker utilization, particularly in patients with hepatitis C.

Virologic and clinical outcomes of hepatitis B virus infection in HIV-HBV coinfected transplant recipients.

Liver transplantation (LT) is the treatment of choice for end-stage liver disease, but is controversial in patients with human immunodeficiency virus (HIV) infection. Using a prospective cohort of HIV-hepatitis B virus (HBV) coinfected patients transplanted between 2001-2007; outcomes including survival and HBV clinical recurrence were determined. Twenty-two coinfected patients underwent LT; 45% had detectable HBV DNA pre-LT and 72% were receiving anti-HBV drugs with efficacy against lamivudine-resistant HBV. Post-LT, all patients received hepatitis B immune globulin (HBIG) plus nucleos(t)ide analogues and remained HBsAg negative without clinical evidence of HBV recurrence, with a median follow-up 3.5 years. Low-level HBV viremia (median 108 IU/mL, range 9-789) was intermittently detected in 7/13 but not associated with HBsAg detection or ALT elevation. Compared with 20 HBV monoinfected patients on similar HBV prophylaxis and median follow-up of 4.0 years, patient and graft survival were similar: 100% versus 85% in HBV mono- versus coinfected patients (p = 0.08, log rank test). LT is effective for HIV-HBV coinfected patients with complications of cirrhosis, including those who are HBV DNA positive at the time of LT. Combination HBIG and antivirals is effective as prophylaxis with no clinical evidence of HBV recurrence but low-level HBV DNA is detectable in approximately 50% of recipients.

Single-Shot Readout Performance of Two Heterojunction-Bipolar-Transistor Amplification Circuits at Millikelvin Temperatures.

High-fidelity single-shot readout of spin qubits requires distinguishing states much faster than the T1 time of the spin state. One approach to improving readout fidelity and bandwidth (BW) is cryogenic amplification, where the signal from the qubit is amplified before noise sources are introduced and room-temperature amplifiers can operate at lower gain and higher BW. We compare the performance of two cryogenic amplification circuits: a current-biased heterojunction bipolar transistor circuit (CB-HBT), and an AC-coupled HBT circuit (AC-HBT). Both circuits are mounted on the mixing-chamber stage of a dilution refrigerator and are connected to silicon metal oxide semiconductor (Si-MOS) quantum dot devices on a printed circuit board (PCB). The power dissipated by the CB-HBT ranges from 0.1 to 1 µW whereas the power of the AC-HBT ranges from 1 to 20 µW. Referred to the input, the noise spectral density is low for both circuits, in the 15 to 30 fA/[Formula: see text] range. The charge sensitivity for the CB-HBT and AC-HBT is 330 µe/[Formula: see text] and 400 µe/[Formula: see text], respectively. For the single-shot readout performed, less than 10 µs is required for both circuits to achieve bit error rates below 10-3, which is a putative threshold for quantum error correction.

Real-world use of elbasvir-grazoprevir in patients with chronic hepatitis C: retrospective analyses from the TRIO network.

BACKGROUND: Elbasvir-grazoprevir is indicated for chronic hepatitis C virus (HCV) genotypes 1 and 4. AIM: To evaluate the utilization and outcomes of chronic HCV patients treated with elbasvir-grazoprevir in the United States. METHODS: We conducted a retrospective cohort study of adults treated with elbasvir-grazoprevir with or without ribavirin for chronic HCV genotypes 1 or 4 infection. Data were collected from healthcare providers and specialty pharmacies through Innervation Platform, a proprietary, cloud-based disease management program from Trio Health. The primary endpoint was per protocol sustained virological response 12 weeks post-treatment (SVR12). RESULTS: Among 470 patients treated in 2016, 95% had HCV genotype 1 infection, 80% (373/468) were HCV treatment naïve and 70% (327/468) had non-cirrhotic disease. Almost 3 quarters (73%) of patients received care in community practices. The majority (89%) of patients received elbasvir-grazoprevir for 12 weeks. Per protocol SVR12 rates were 99% (396/402) for HCV genotype 1 and 95% (21/22) for HCV genotype 4. Among patients with Stage 4 or 5 chronic kidney diseases, 99% (113/114) achieved SVR12. In univariate analyses, variables significantly associated with per protocol SVR12 for the entire sample were therapy duration (P = 0.001), treatment experience (P = 0.016), and cirrhosis status (P = 0.001). However, among HCV genotype 1 patients, no variables were significant. Intent-to-treat SVR12 rates were 89% (396/447) for HCV genotype 1 and 91% (21/23) for HCV genotype 4. CONCLUSION: Elbasvir-grazoprevir is highly effective, and in this 2016 cohort, its use was predominantly in patients with HCV genotype 1 and as a 12-week therapy without ribavirin.