Browsing by Subject "Antiviral agents"

Now showing 1 - 6 of 6
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    Changing Trends of Cirrhotic and Noncirrhotic Hepatocellular Carcinoma in the Era of Directly-Acting Antiviral Agents
    (Wolters Kluwer, 2021-11-03) Mathur, Karan; Mazhar, Areej; Patel, Milin; Dakhoul, Lara; Burney, Heather; Liu, Hao; Nephew, Lauren; Chalasani, Naga; deLemos, Andrew; Gawrieh, Samer; Medicine, School of Medicine
    Introduction: The impact of direct-acting antivirals (DAAs) for hepatitis C virus (HCV) on burden of cirrhotic and noncirrhotic hepatocellular carcinoma (HCC) has not been examined. We assessed recent trends in liver disease etiologies of HCC and proportion of noncirrhotic HCC since DAAs introduction. Methods: Clinical characteristics including presence or absence of underlying cirrhosis were collected from 2,623 patients diagnosed with HCC between 2009 and 2019 at 2 large US centers. Logistic regression was performed to investigate the annual trends of HCC due to different liver diseases and proportions of noncirrhotic cases. Results: In the DAA era (2014-2019), annual decline in HCV-HCC (odds ratio [OR] = 0.93, 95% confidence interval [CI] 0.88-0.99, P = 0.019), without change in trends of other liver diseases-related HCC, was observed. Annual increase in noncirrhotic HCC (OR 1.13, 95% CI 1.03-1.23, P = 0.009) and decline in cirrhotic HCC (OR 0.89, 95% CI 0.81-0.97, P = 0.009) along with similar trends for HCV-HCC-increase in noncirrhotic cases (OR 1.35, 95% CI 1.08-1.69, P = 0.009) and decrease in cirrhotic cases (OR 0.92, 95% CI 0.86-0.98, P = 0.012)-were observed during the DAA era. Compared with the pre-DAA era, HCC resection rate increased (10.7% vs 14.0%, P = 0.013) whereas liver transplantation rate decreased (15.1% vs 12.0%, P = 0.023) in the DAA era. Discussion: Since introduction of DAAs, proportions of cirrhotic HCC have decreased, whereas proportions of noncirrhotic HCC have increased. These new trends were associated with change in utilization of liver resection and transplantation for HCC. The impact of changing patterns of DAA use on these trends will require further study.
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    Evaluation of US Food and Drug Administration Drug Label Recommendations for Coadministration of Antivirals and Acid-Reducing Agents
    (Wiley, 2022) Shugg, Tyler; Powell, Nicholas R.; Marroum, Patrick J.; Skaar, Todd C.; Younis, Islam R.; Medicine, School of Medicine
    Coadministration with acid-reducing agents (ARAs), including proton pump inhibitors (PPIs), histamine H2 -receptor antagonists (H2 blockers), and antacids has been demonstrated to reduce antiviral exposure and efficacy. Therefore, it is essential that US Food and Drug Administration (FDA) drug labels include recommendations to manage these drug-drug interactions (DDIs). This investigation analyzed information in FDA drug labels to manage DDIs between ARAs and antivirals approved from 1998 to 2019. To ascertain clinical adoption, we assessed whether FDA label recommendations were incorporated into current antiviral clinical practice guidelines. We identified 82 label recommendations for 43 antiviral approvals. Overall, 56.1% of recommendations were deemed clinically actionable, with the most common actionable management strategies being dose adjustment during coadministration (40.2%) and coadministration not recommended (9.8%). The sources informing DDI recommendations were clinical DDI studies (59.8%) and predictions of altered exposure (40.2%). Antivirals with low aqueous solubility were more likely to have label recommendations and were more commonly investigated using clinical DDI studies (P < 0.01). For recommendations informed by clinical DDI studies, changes in drug exposure were associated with actionable label recommendations (P < 0.01). The frequency of exposure changes in clinical DDI studies was similar across antiviral indications, but exposure changes were numerically higher for antacids (71.4%) relative to PPIs (42.9%) and H2 blockers (28.6%). Of DDI pairs identified within drug labels, 76.8% were included in guidelines, and recommended management strategies were concordant in 90.5% of cases. Our findings demonstrate that current regulatory oversight mostly (but not completely) results in actionable label recommendations to manage DDIs for high-risk antivirals.
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    Host functions used by hepatitis B virus to complete its life cycle: Implications for developing host-targeting agents to treat chronic hepatitis B
    (Elsevier, 2018-10) Mitra, Bidisha; Thapa, Roshan J.; Guo, Haitao; Block, Timothy M.; Microbiology and Immunology, School of Medicine
    Similar to other mammalian viruses, the life cycle of hepatitis B virus (HBV) is heavily dependent upon and regulated by cellular (host) functions. These cellular functions can be generally placed in to two categories: (a) intrinsic host restriction factors and innate defenses, which must be evaded or repressed by the virus; and (b) gene products that provide functions necessary for the virus to complete its life cycle. Some of these functions may apply to all viruses, but some may be specific to HBV. In certain cases, the virus may depend upon the host function much more than does the host itself. Knowing which host functions regulate the different steps of a virus' life cycle, can lead to new antiviral targets and help in developing novel treatment strategies, in addition to improving a fundamental understanding of viral pathogenesis. Therefore, in this review we will discuss known host factors which influence key steps of HBV life cycle, and further elucidate therapeutic interventions targeting host-HBV interactions.
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    Middle East Respiratory Syndrome Coronavirus
    (Thieme, 2021) Al-Tawfiq, Jaffar A.; Azhar, Esam I.; Memish, Ziad A.; Zumla, Alimuddin; Medicine, School of Medicine
    The past two decades have witnessed the emergence of three zoonotic coronaviruses which have jumped species to cause lethal disease in humans: severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1), Middle East respiratory syndrome coronavirus (MERS-CoV), and SARS-CoV-2. MERS-CoV emerged in Saudi Arabia in 2012 and the origins of MERS-CoV are not fully understood. Genomic analysis indicates it originated in bats and transmitted to camels. Human-to-human transmission occurs in varying frequency, being highest in healthcare environment and to a lesser degree in the community and among family members. Several nosocomial outbreaks of human-to-human transmission have occurred, the largest in Riyadh and Jeddah in 2014 and South Korea in 2015. MERS-CoV remains a high-threat pathogen identified by World Health Organization as a priority pathogen because it causes severe disease that has a high mortality rate, epidemic potential, and no medical countermeasures. MERS-CoV has been identified in dromedaries in several countries in the Middle East, Africa, and South Asia. MERS-CoV-2 causes a wide range of clinical presentations, although the respiratory system is predominantly affected. There are no specific antiviral treatments, although recent trials indicate that combination antivirals may be useful in severely ill patients. Diagnosing MERS-CoV early and implementation infection control measures are critical to preventing hospital-associated outbreaks. Preventing MERS relies on avoiding unpasteurized or uncooked animal products, practicing safe hygiene habits in health care settings and around dromedaries, community education and awareness training for health workers, as well as implementing effective control measures. Effective vaccines for MERS-COV are urgently needed but still under development.
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    Rapid Turnover of Hepatitis B Virus Covalently Closed Circular DNA Indicated by Monitoring Emergence and Reversion of Signature-Mutation in Treated Chronic Hepatitis B Patients
    (Wiley, 2021) Huang, Qi; Zhou, Bin; Cai, Dawei; Zong, Yuhua; Wu, Yaobo; Liu, Shi; Mercier, Alexandre; Guo, Haitao; Hou, Jinlin; Colonno, Richard; Sun, Jian; Microbiology and Immunology, School of Medicine
    Background and aims: Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) plays a pivotal role in the establishment and persistence of HBV infection. Understanding the turnover time of preexisting cccDNA pools would be helpful in designing strategies to clear HBV by fully blocking the de novo generation of cccDNA. Approach and results: In this study, we retrospectively monitored the emergence and reversion of the rtM204I/V mutant, a signature lamivudine resistance (LAMR ) mutation serving as a biomarker of cccDNA turnover in liver biopsies and longitudinal serum samples from two clinical trials. Methodologies were optimized to differentially isolate and sequence HBV virion DNA, cccDNA, and HBV RNA from clinical samples. A strong correlation was observed between LAMR composition of cccDNA with that of serum and intrahepatic HBV RNA in paired liver and serum samples (r = 0.96 and 0.90, respectively), suggesting that serum HBV RNA can serve as a surrogate marker of cccDNA genetic composition when liver biopsies are unavailable. LAMR mutations emerged and increased from undetectable to 40%-90% within 16-28 weeks in serum HBV RNA from telbivudine-treated patients experiencing virological breakthrough. Similarly, in lamivudine-resistant patients who switched to interferon therapy, serum HBV-RNA population bearing 100% LAMR mutations fully reversed back to wild type within 24-48 weeks. Conclusions: The genetic composition dynamics of serum HBV RNA and biopsy cccDNA in treated HBV patients indicates that cccDNA turnover occurs relatively rapidly (several months), offering a possibility of HBV cure with finite therapy through completely blocking cccDNA replenishment.
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    Simeprevir plus sofosbuvir (12 and 8 weeks) in hepatitis C virus genotype 1-infected patients without cirrhosis: OPTIMIST-1, a phase 3, randomized study
    (Wiley, 2016-08) Kwo, Paul; Gitlin, Norman; Nahass, Ronald; Bernstein, David; Etzkorn, Kyle; Rojter, Sergio; Schiff, Eugene; Davis, Mitchell; Ruane, Peter; Younes, Ziad; Kalmeijer, Ronald; Sinha, Rekha; Peeters, Monika; Lenz, Oliver; Fevery, Bart; De La Rosa, Guy; Scott, Jane; Witek, James; Department of Medicine, IU School of Medicine
    Effective antiviral therapy is essential for achieving sustained virological response (SVR) in hepatitis C virus (HCV)-infected patients. The phase 2 COSMOS study reported high SVR rates in treatment-naive and prior null-responder HCV genotype (GT) 1-infected patients receiving simeprevir+sofosbuvir±ribavirin for 12 or 24 weeks. OPTIMIST-1 (NCT02114177) was a multicenter, randomized, open-label study assessing the efficacy and safety of 12 and 8 weeks of simeprevir+sofosbuvir in HCV GT1-infected treatment-naive and treatment-experienced patients without cirrhosis. Patients were randomly assigned (1:1; stratified by HCV GT/subtype and presence or absence of NS3 Q80K polymorphism [GT1b, GT1a with Q80K, GT1a without Q80K]), prior HCV treatment history, and IL28B GT [CC, non-CC]) to simeprevir 150 mg once daily+sofosbuvir 400 mg once daily for 12 or 8 weeks. The primary efficacy endpoint was SVR rate 12 weeks after end of treatment (SVR12). Superiority in SVR12 was assessed for simeprevir+sofosbuvir at 12 and 8 weeks versus a composite historical control SVR rate. Enrolled were 310 patients, who were randomized and received treatment (n = 155 in each arm). SVR12 with simeprevir+sofosbuvir for 12 weeks (97% [150/155; 95% confidence interval 94%-100%]) was superior to the historical control (87%). SVR12 with simeprevir+sofosbuvir for 8 weeks (83% [128/155; 95% confidence interval 76-89%]) was not superior to the historical control (83%). The most frequent adverse events were nausea, headache, and fatigue (12-week arm: 15% [23/155], 14% [22/155], and 12% [19/155]; 8-week arm: 9% [14/155], 17% [26/155], and 15% [23/155], respectively). No patients discontinued treatment due to an adverse event. One (1%, 12-week arm) and three (2%, 8-week arm) patients experienced a serious adverse event (all unrelated to study treatment). CONCLUSION: Simeprevir+sofosbuvir for 12 weeks is highly effective in the treatment of HCV GT1-infected patients without cirrhosis, including those with Q80K. (Hepatology 2016;64:370-380).