Longitudinal Circulating Tumor DNA Analysis in Blood and Saliva for Prediction of Response to Osimertinib and Disease Progression in EGFR-Mutant Lung Adenocarcinoma.

Background: We assessed whether serial ctDNA monitoring of plasma and saliva predicts response and resistance to osimertinib in EGFR-mutant lung adenocarcinoma. Three ctDNA technologies-blood-based droplet-digital PCR (ddPCR), next-generation sequencing (NGS), and saliva-based EFIRM liquid biopsy (eLB)-were employed to investigate their complementary roles. Methods: Plasma and saliva samples were collected from patients enrolled in a prospective clinical trial of osimertinib and local ablative therapy upon progression (NCT02759835). Plasma was analyzed by ddPCR and NGS. Saliva was analyzed by eLB. Results: A total of 25 patients were included. We analyzed 534 samples by ddPCR (n = 25), 256 samples by NGS (n = 24) and 371 samples by eLB (n = 22). Among 20 patients who progressed, ctDNA progression predated RECIST 1.1 progression by a median of 118 days (range: 61-272 days) in 11 (55%) patients. Of nine patients without ctDNA progression by ddPCR, two patients had an increase in mutant EGFR by eLB and two patients were found to have ctDNA progression by NGS. Levels of ctDNA measured by ddPCR and NGS at early time points, but not volumetric tumor burden, were associated with PFS. EGFR/ERBB2/MET/KRAS amplifications, EGFR C797S, PIK3CA E545K, PTEN V9del, and CTNNB1 S45P were key resistance mechanisms identified by NGS. Conclusion: Serial assessment of ctDNA in plasma and saliva predicts response and resistance to osimertinib, with each assay having supplementary roles.

Clonal Evolution and Heterogeneity of Osimertinib Acquired Resistance Mechanisms in EGFR Mutant Lung Cancer.

Clonal evolution of osimertinib-resistance mechanisms in EGFR mutant lung adenocarcinoma is poorly understood. Using multi-region whole-exome and RNA sequencing of prospectively collected pre- and post-osimertinib-resistant tumors, including at rapid autopsies, we identify a likely mechanism driving osimertinib resistance in all patients analyzed. The majority of patients acquire two or more resistance mechanisms either concurrently or in temporal sequence. Focal copy-number amplifications occur subclonally and are spatially and temporally separated from common resistance mutations such as EGFR C797S. MET amplification occurs in 66% (n = 6/9) of first-line osimertinib-treated patients, albeit spatially heterogeneous, often co-occurs with additional acquired focal copy-number amplifications and is associated with early progression. Noteworthy osimertinib-resistance mechanisms discovered include neuroendocrine differentiation without histologic transformation, PD-L1, KRAS amplification, and ESR1-AKAP12, MKRN1-BRAF fusions. The subclonal co-occurrence of acquired genomic alterations upon osimertinib resistance will likely require targeting multiple resistance mechanisms by combination therapies.

No Improvement in Hemoglobin A1c Following Hepatitis C Viral Clearance in Patients With and Without HIV.

Hepatitis C clearance with directly acting antivirals (DAAs) may be associated with acute decreases in hemoglobin A1c (HbA1c). We prospectively evaluated 251 chronic hepatitis C virus (HCV)-infected subjects (31% human immunodeficiency virus [HIV] positive) pre- and post-DAA therapy (median follow-up 28 months). Changes in HbA1c and glucose were minimal and did not differ by sustained virologic response (SVR), HIV, diabetes, or fibrosis. Following SVR, mean change in HbA1c was -0.022 ± 0.53%; however, total and low-density lipoprotein cholesterol increased significantly. Subjects with HIV had smaller transaminase reductions after SVR. Sustained benefits in glycemia were not identified following HCV clearance irrespective of HIV, diabetes, or fibrosis stage, whereas lipid alterations may warrant further investigation.

Expansion of Treatment for Hepatitis C Virus Infection by Task Shifting to Community-Based Nonspecialist Providers: A Nonrandomized Clinical Trial.

Background: Direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) infection has resulted in high rates of disease cure; however, not enough specialists currently are available to provide care. Objective: To determine the efficacy of HCV treatment independently provided by nurse practitioners (NPs), primary care physicians (PCPs), or specialist physicians using DAA therapy. Design: Nonrandomized, open-label clinical trial initiated in 2015. (ClinicalTrials.gov: NCT02339038). Setting: 13 urban, federally qualified health centers (FQHCs) in the District of Columbia. Patients: A referred sample of 600 patients, of whom 96% were black, 69% were male, 82% were treatment naive, and 20% had cirrhosis. Seventy-two percent of the patients had HCV genotype 1a infection. The baseline characteristics of patients seen by each provider type were similar. Intervention: Patients were assigned in a nonrandomized but specified manner to receive treatment from 1 of 5 NPs, 5 PCPs, or 6 specialists. All providers underwent an identical 3-hour training session based on guidelines. Patients received treatment with ledipasvir-sofosbuvir, which was provided on site, according to U.S. Food and Drug Administration labeling requirements. Measurements: Sustained virologic response (SVR). Results: 516 patients achieved SVR, a response rate of 86% (95% CI, 83.0% to 88.7%), with no major safety signals. Response rates were consistent across the 3 provider types: NPs, 89.3% (CI, 83.3% to 93.8%); PCPs, 86.9% (CI, 80.6% to 91.7%); and specialists, 83.8% (CI, 79.0% to 87.8%). Patient loss to follow-up was the major cause of non-SVR. Limitation: Nonrandomized patient distribution; possible referral bias. Conclusion: In a real-world cohort of patients at urban FQHCs, HCV treatment administered by nonspecialist providers was as safe and effective as that provided by specialists. Nurse practitioners and PCPs with compact didactic training could substantially expand the availability of community-based providers to escalate HCV therapy, bridging existing gaps in the continuum of care for patients with HCV infection. Primary Funding Source: National Institutes of Health and Gilead Sciences.

HIV/HCV Co-infection: Overcoming Barriers to Treatment.

A critical step in the eradication of hepatitis C virus (HCV) infection is access to effective therapy. With the advent of interferon-free regimens, HCV providers and patients gained hope that the success seen in clinical trials could be translated to the real world. However, the exorbitant cost of the new direct-acting antivirals limits access to these medications to the general HCV population, especially underserved patients with public insurance. We used a descriptive qualitative approach to detail the measures necessary and challenges faced by an inner-city nursing team in Washington, DC to obtain the new direct-acting antivirals. Significant time and dedication on the part of providers and staff was required to assist patients with the process of obtaining direct-acting antivirals.

Moderate Sustained Virologic Response Rates With 6-Week Combination Directly Acting Anti-Hepatitis C Virus Therapy in Patients With Advanced Liver Disease.

BACKGROUND: Treatment of genotype 1 hepatitis C virus (HCV) infection with combination directly acting antivirals (DAA) for 8-24 weeks is associated with high rates of sustained virologic response (SVR). We previously demonstrated that adding a third DAA to ledipasvir and sofosbuvir (LDV/SOF) can result in high SVR rates in patients without cirrhosis. In this study, we investigated whether a similar regimen would yield equivalent rates of cure in patients with advanced liver fibrosis. METHODS: Fifty patients were enrolled at the Clinical Research Center of the National Institutes of Health and associated healthcare centers. Enrollment and follow-up data from April 2014 to June 2015 are reported here. Eligible participants were aged ≥18 years, had chronic HCV genotype 1 infection (serum HCV RNA ≥2000 IU/mL), and stage 3-4 liver fibrosis. HCV RNA was measured using a reverse-transcription polymerase chain reaction assay. RESULTS: Of patients treated with LDV, SOF, and the NS3/4A protease inhibitor GS-9451 for 6 weeks, 76% (38 of 50; 95% confidence interval, 60%-85%) had SVR achieved 12 weeks after the end of treatment. There was no statistically significant difference in treatment efficacy between treatment-naive patients (72%, 18 of 25) and those with treatment experience (80%; 20 of 25) (P = .51). Overall, 11 patients (22%) experienced virologic relapse, and 1 (2%) was lost to follow-up at 4 weeks after treatment. No serious adverse events, discontinuations, or deaths were associated with this regimen. CONCLUSIONS: Adding a third DAA to LDV/SOF may result in a moderate SVR rate, lower than that observed in patients without cirrhosis. Significant liver fibrosis remains an impediment to achieving SVR with short-duration DAA therapy. CHINESE CLINICAL TRIALS REGISTRATION: CT01805882.

Successful Retreatment of Chronic HCV Genotype-1 Infection With Ledipasvir and Sofosbuvir After Initial Short Course Therapy With Direct-Acting Antiviral Regimens.

BACKGROUND: The optimal retreatment strategy for chronic hepatitis C virus (HCV) patients who fail directly-acting antiviral agent (DAA)-based treatment is unknown. In this study, we assessed the efficacy and safety of ledipasvir (LDV) and sofosbuvir (SOF) for 12 weeks in HCV genotype-1 (GT-1) patients who failed LDV/SOF-containing therapy. METHODS: In this single-center, open-label, phase 2a trial, 34 participants with HCV (GT-1) and early-stage liver fibrosis who previously failed 4-6 weeks of LDV/SOF with GS-9669 and/or GS-9451 received LDV/SOF for 12 weeks. The primary endpoint was HCV viral load below the lower limit of quantification 12 weeks after completion of therapy (sustained virological response [SVR]12). Deep sequencing of the NS3, NS5A, and NS5B regions were performed at baseline, at initial relapse, prior to retreatment, and at second relapse with Illumina next-generation sequencing technology. RESULTS: Thirty-two of 34 enrolled participants completed therapy. Two patients withdrew after day 0. Participants were predominantly male and black, with median baseline HCV viral load of 1.3 × 10(6) IU/mL and Metavir fibrosis stage 1 and genotype-1a. Median time from relapse to retreatment was 22 weeks. Prior to retreatment, 29 patients (85%) had NS5A-resistant variants. The SVR12 rate was 91% (31/34; intention to treat, ITT) after retreatment. One patient relapsed. CONCLUSIONS: In patients who previously failed short-course combination DAA therapy, we demonstrate a high SVR rate in response to 12 weeks of LDV/SOF, even for patients with NS5A resistance-associated variants. CLINICAL TRIALS REGISTRATION: NCT01805882.

Four-Week Direct-Acting Antiviral Regimens in Noncirrhotic Patients With Hepatitis C Virus Genotype 1 Infection: An Open-Label, Nonrandomized Trial.

BACKGROUND: Treatment of chronic hepatitis C virus (HCV) infection with direct-acting antivirals (DAAs) for 6 weeks achieves sustained virologic response (SVR) rates of 95% in some patients. If effective, shorter therapeutic courses could improve adherence and treatment costs. OBJECTIVE: To determine factors predictive of SVR to 4 weeks of DAA treatment in patients with stage F0 to F2 liver fibrosis. DESIGN: Open-label, nonrandomized, phase 2a trial. (Clinical Trials.gov: NCT01805882). SETTING: Single-center. PATIENTS: 50 treatment-naive and predominantly African American patients with HCV genotype 1 infection and early-stage liver fibrosis were sequentially enrolled into 2 treatment groups. INTERVENTION: 25 participants received a 3-drug regimen consisting of ledipasvir and sofosbuvir plus GS-9451 for 4 weeks, and 25 received a 4-drug regimen consisting of ledipasvir, sofosbuvir, GS-9451, and GS-9669 for 4 weeks. MEASUREMENTS: The primary efficacy end point was SVR12 (HCV RNA level below the lower limit of quantification at posttreatment week 12). RESULTS: Forty percent (10 of 25) (95% CI, 21% to 61%) of patients in the 3-drug group and 20% (5 of 25) (CI, 7% to 41%) of those in the 4-drug group achieved SVR12. Exploratory analysis suggested that lower baseline HCV viral load, younger age, and HCV genotype 1b were associated with SVR12. Ten patients had baseline HCV variants conferring greater than 20-fold resistance in vitro to at least 1 study DAA; all had viral relapse. Forty-eight percent (12 of 25) of patients receiving the 3-drug regimen and 72% (18 of 25) of those receiving the 4-drug regimen had adverse events, most of which were mild. One participant was lost to follow-up. LIMITATION: Nonrandomized study design and small sample of patients with early-stage fibrosis. CONCLUSION: Combination DAA therapy with 3 or 4 drugs for 4 weeks was well-tolerated but resulted in limited cure rates. PRIMARY FUNDING SOURCE: National Institute of Allergy and Infectious Diseases, National Cancer Institute, and Clinical Center Intramural Program; supported in part by a cooperative research and development agreement between the National Institutes of Health and Gilead Sciences.