Efficacy and safety of telaprevir and boceprevir in patients with hepatitis C genotype 1: a meta-analysis

Viral hepatitis in 2021: The challenges remaining and how we should tackle them

Viral hepatitis results in 1.4 million deaths annually. The World Health Organization (WHO) set an ambitious target to eliminate viral hepatitis by 2030, but significant challenges remain. These include inequalities in access to healthcare, reaching at risk populations and providing access to screening and effective treatment. Stigma around viral hepatitis persists and must be addressed. The WHO goal of global elimination by 2030 is a worthy aim, but remains ambitious and the coronavirus 2019 pandemic undoubtedly has set back progress. This review article will focus on hepatitis A to E, highlighting problems that have been resolved in the field over the past decade, those that remain to be resolved and suggest directions for future problem solving and research.

Access to New Medications for Hepatitis C for Medicaid Members: A Retrospective Cohort Study

BACKGROUND

Sofosbuvir (SOF)- or simeprevir (SIM)-containing regimens are highly effective for treating chronic hepatitis C virus (HCV) infection. These regimens, however, are expensive. Most payers have implemented prior authorization (PA) requirements to ensure that patients who can benefit most have priority for these medications. While many Medicaid programs limit access to those with advanced disease or to members who do not have active substance use disorder (SUD), the Massachusetts Medicaid (MassHealth) Primary Care Clinician (PCC) plan does not limit access based on disease severity or presence of SUD. Evaluating PA requests for SOF and/or SIM among MassHealth members will offer a useful example of early uptake among Medicaid members and will identify patient groups who might face barriers to treatment at the provider or patient level.

OBJECTIVES

To (a) evaluate the percentage of MassHealth PCC members with HCV who had a PA request, along with the percentage of requests approved, and (b) identify characteristics associated with PA requests for SOF or SIM among Massachusetts Medicaid (MassHealth) members with HCV.

METHODS

This retrospective cohort study used enrollment, medical claims, and PA request data from MassHealth PCC members from December 6, 2012, to July 31, 2014. The sample included members with 1 or more claims with an ICD-9-CM code for HCV during this time who were continuously enrolled from December 6, 2013, to July 31, 2014. Enrollment and medical claims data for the cohort with HCV were linked to a database containing information collected from PA requests. The overall percentage of members with HCV and a PA request for SOF and/or SIM between December 6, 2013, and July 31, 2014, and the percentage of requests approved were calculated. Chi-square statistics were used to compare demographic and clinical characteristics among members with HCV who did and did not have a request. Logistic regression was used to estimate the strength of associations between patient characteristics and a PA treatment request, adjusting for clinical and demographic variables.

RESULTS

Of 6,849 members identified with HCV, 346 (5.1%) had a PA request for SOF and/or SIM submitted to MassHealth. Compared with members with HCV who did not have a PA request for SOF or SIM, those with a PA request for these new treatments were more likely to be male (P = 0.01), older (P < 0.001), white race (P = 0.04), have standard MassHealth insurance (P = 0.01), and less likely to be homeless (P < 0.001). Members with a PA request were also more likely to have been treated for HCV in the past year and have advanced disease (hepatic decompensation, cirrhosis, or liver transplant) but less likely to have SUD (P < 0.001 for each). Ninety percent of requests for SOF or SIM were approved; few demographic or clinical characteristics were associated with approval. In adjusted analyses, predictors of PA request were aged 50-64 years (odds ratio (OR) = 2.0, 95% CI = 1.1-3.7 vs. aged < 30 years); hepatic decompensation (OR = 1.6, 95% CI = 1.2-2.3); cirrhosis (OR = 3.0, 95% CI = 2.2-4.1); liver transplant (OR = 3.0, 95% CI = 1.4-6.5); substance use (OR = 0.6, 95% CI = 0.5-0.8); recent HCV treatment (OR = 1.6, 95% CI = 1.0-2.6); comorbidity (OR = 0.95, 95% CI = 0.91-0.98) for 1-unit increase in Diagnostic Cost Group score; and care at a hospital outpatient department (OR = 2.0, 95% CI = 1.2-3.2 vs. group practice).

CONCLUSIONS

Antiviral treatment with SOF and/or SIM was requested for a relatively small proportion of MassHealth members with HCV, with nearly all approved. Prescriber prioritization or patient barriers to care, rather than the PA process, determined access to treatment in this Medicaid population. Support may be needed to ensure patients with SUD benefit from advances in HCV treatment.

DISCLOSURES

No outside funding supported this research. Internal funding was provided by the Commonwealth of Massachusetts. Lavitas has received compensation from University of Tennessee Advanced Studies in Medicine for development of CPE activity. Graham has consulted for the National Viral Hepatitis Roundtable and the Department of Health and Human Services, has received payment from Medscape for CME development, and is employed by Trek Therapeutics. Jeffrey has received payment for guest lectures at Boston University and Harvard University. Study concept and design were primarily contributed by Clark and Clements, along with Graham, Lenz, and Jeffrey. Kunte collected the data, which were interpreted by Graham, Lenz, and Jeffrey, with assistance from Lavitas, Clark, and Clements. The manuscript was written primarily by Clements, along with O'Connell and assisted by Graham, and revised by all the authors.

Cost-effectiveness of direct-acting antiviral regimen ombitasvir/paritaprevir/ritonavir in treatment-naïve and treatment-experienced patients infected with chronic hepatitis C virus genotype 1b in Japan

OBJECTIVE

This study compared the cost-effectiveness of chronic hepatitis C virus (HCV) genotype 1b (GT1b) therapy ombitasvir/paritaprevir/ritonavir (OBV/PTV/r) vs daclatasvir + asunaprevir (DCV/ASV) and no treatment in patients without cirrhosis. Cost-effectiveness analyses (CEAs) that compared OBV/PTV/r against DCV/ASV and sofosbuvir/ledipasvir (SOF/LDV) in Y93H mutation-negative, GT1b patients with and without cirrhosis were also included.

METHODS

A health state transition model was developed to capture the natural history of HCV. A CEA over a lifetime horizon was performed from the perspective of the public healthcare payer in Japan. Costs, health utilities, and rates of disease progression were derived from published studies. Sustained virologic response (SVR) rates of OBV/PTV/r and DCV/ASV were extracted from Japanese clinical trials. Analyses were performed for treatment-naïve and -experienced patients. Alternative scenarios and input parameter uncertainty on the results were tested.

RESULTS

OBV/PTV/r exhibited superior clinical outcomes vs comparators. For OBV/PTV/r, DCV/ASV, and no treatment, the lifetime risk of decompensated cirrhosis in treatment-naïve patients without cirrhosis was 0.4%, 1.4%, and 9.2%, and hepatocellular carcinoma was 6.5%, 11.4%, and 49.9%, respectively. Quality-adjusted life years (QALYs) were higher in treatment-naïve and -experienced patients without cirrhosis treated with OBV/PTV/r (16.41 and 16.22) vs DCV/ASV (15.83 and 15.66) or no treatment (11.34 and 11.23). In treatment-naïve and -experienced patients without cirrhosis, the incremental cost-effectiveness ratios (ICERs) of OBV/PTV/r vs DCV/ASV were JPY 1,684,751/QALY and JPY 1,836,596/QALY, respectively; OBV/PTV/r was dominant compared with no treatment. In scenario analysis, including GT1b patients with and without cirrhosis who were Y93H mutation-negative, the ICER of OBV/PTV/r vs DCV/ASV was below the Japanese willingness-to-pay threshold of JPY 5 million/QALY, while the ICER of SOF/LDV vs OBV/PTV/r was above this threshold; thus, OBV/PTV/r was cost-effective.

CONCLUSION

OBV/PTV/r appears to be a cost-effective treatment for chronic HCV GT1b infection against DCV/ASV. OBV/PTV/r dominates no treatment in patients without cirrhosis.

Do disparities between populations in randomized controlled trials and the real world lead to differences in outcomes?

AIM

To conduct a systematic review investigating reasons for the disparity between the efficacy and effectiveness rates reported in randomized controlled trials (RCTs) and observational studies of direct-acting antiviral treatment regimens licensed for use in genotype1 hepatitis C virus-infected individuals.

METHODS

This systematic review was conducted in accordance with the criteria of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses group.

RESULTS

Statistically significant (p < 0.05) differences in the baseline demographics and sustained virological response rates were observed between RCT and observational studies.

CONCLUSION

In order for outcomes from RCTs to be generalizable to the real world, greater consideration needs to be taken to include patient populations that are more representative of those awaiting treatment in the clinical setting.

Network meta-analysis of first- and second-generation protease inhibitors for chronic hepatitis C genotype 1: efficacy based on RVR and SVR 24

PURPOSE

This study aimed to compare the efficacy among direct-acting antiviral agents (first and second-generation direct-acting antiviral agents (DAAs)) with placebo and with standard dual therapy (pegylated interferon + ribavirin (Peg-IFN + RBV)) in terms of rapid virologic response (RVR) and sustained virologic response (SVR) in chronic hepatitis C genotype 1 treatment.

METHODS

We performed a systematic review of randomized controlled trials (RCTs) in MEDLINE, International Pharmaceutical Abstracts, Cochrane Library, SCIELO, and Scopus and conducted a network meta-analysis to compare the efficacy of boceprevir (BOC), daclatasvir (DCV), grazoprevir, simeprevir (SMV) and telaprevir (TVR), in treatment-naive and treatment-experienced patients.

RESULTS

Sixteen studies encompassing 7171 patients were analysed. Associations between DAAs therapies (IFN-free regimens) could not be addressed since no common comparator was found in the RCTs among these associations and the other agents included in the present analysis. All agents were more efficacious than placebo or Peg-IFN + RBV in terms of RVR, while only BOC and SMV showed statistically significant superiority for the SVR outcome when compared to placebo or standard dual therapy. No significant differences between the DAAs were observed. The analysis prioritized treatment with DCV for both efficacy outcomes. Node-splitting analysis showed that our networks are robust (p > 0.05).

CONCLUSIONS

The superiority of DAAs over placebo or standard dual therapy with Peg-IFN + RBV was confirmed, indicating the greater efficacy of DCV. This study is the first network meta-analysis that included RVR as an outcome in the evaluation of these agents via indirect comparison. Further investigation should be carried out addressing safety and tolerability outcomes.

2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph

The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph".

Safety of interferon-free therapies for chronic hepatitis C: a network meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Interferon-free (IFN-free) therapies for hepatitis C virus (HCV) have been developed to provide more effective, tolerable and safer therapeutic strategies. To date, no network meta-analysis (NMA) evaluating the safety profile of these regimens has been performed. This systematic review and NMA aimed to evaluate safety outcomes of IFN-free treatment options for chronic hepatitis C.

METHODS

A systematic review was performed according to PRISMA and Cochrane recommendations. A literature search was conducted in PubMed/Medline, Scopus, Cochrane Library, International Pharmaceutical Abstracts and Web of Science electronic databases and included only randomized clinical trials that provided safety outcomes of interest of evaluated second-generation direct-acting antivirals: incidence of any adverse events (AEs) and serious AE. NMA allowed estimating probability for the relative safety of the interventions. A consistency model was used to draw conclusions about relative safety of treatments, presented as odds ratio (OR) and corresponding 95% credible interval (CrI).

RESULTS

Fifty-one clinical trials were included (13 089 participants). Most participants had hepatitis C genotype 1 virus (76%) and were treated for 12 weeks. Two NMAs were built to investigate the incidence of AEs and serious AEs, comparing 13 and 10 IFN-free treatment options, respectively. For the outcome incidence of AEs, few significant differences were observed, which were explained by the presence of RBV. Elbasvir with grazoprevir and placebo were both safer than ombitasvir in combination with paritaprevir, ritonavir, daclatasvir plus RBV [ORs with 95% Crl of 4·09 (1·17-14·09) and 2·40 (1·19-4·77), respectively] and sofosbuvir with RBV [ORs with 95% Crl of 0·22 (0·07-0·72) and 2·69 (1·53-4·80), respectively]. Furthermore, elbasvir with grazoprevir was safer than sofosbuvir used with velpatasvir and RBV [OR 0·19 (95% CrI 0·03-0·98)]; ombitasvir in combination with paritaprevir, ritonavir, daclatasvir was safer than the same therapy but combined with RBV [OR 2·14 (95% CrI 1·09-4·44)]; and sofosbuvir used with velpatasvir was safer than sofosbuvir with RBV [OR 2·07 (95% CrI 1·13-3·79)]. Elbasvir with grazoprevir (50%) followed by placebo (28%) had the highest probabilities of less AEs. No significant differences were observed for serious AE outcomes.

WHAT IS NEW AND CONCLUSION

This meta-analysis included a large number of therapies. Small differences were observed in any AEs, but not in serious AEs.

A new paradigm evaluating cost per cure of HCV infection in the UK

Background

New interferon (IFN)-free treatments for hepatitis C are more effective, safer but more expensive than current IFN-based therapies. Comparative data of these, versus current first generation protease inhibitors (PI) with regard to costs and treatment outcomes are needed. We investigated the real-world effectiveness, safety and cost per cure of 1st generation PI-based therapies in the UK.

Methods

Medical records review of patients within the HCV Research UK database. Patients had received treatment with telaprevir or boceprevir and pegylated interferon and ribavirin (PR). Data on treatment outcome, healthcare utilisation and adverse events (AEs) requiring intervention were collected and analysed overall and by subgroups. Costs of visits, tests, therapies, adverse events and hospitalisations were estimated at the patient level. Total cost per cure was calculated as total median cost divided by SVR rate.

Results

154 patients from 35 centres were analysed. Overall median total cost per cure was £44,852 (subgroup range,: £35,492 to £107,288). Total treatment costs were accounted for by PI: 68.3 %, PR: 26.3 %, AE management: 5.4 %. Overall SVR was 62.3 % (range 25 % to 86.2 %). 36 % of patients experienced treatment-related AEs requiring intervention, 10 % required treatment-related hospitalisation.

Conclusions

This is the first UK multicentre study of outcomes and costs of PI-based HCV treatments in clinical practice. There was substantial variation in total cost per cure among patient subgroups and high rates of treatment-related discontinuations, AEs and hospitalisations. Real world safety, effectiveness and total cost per cure for the new IFN free combinations should be compared against this baseline.

Electronic supplementary material

The online version of this article (doi:10.1186/s41124-016-0002-z) contains supplementary material, which is available to authorized users.

Triple Therapy with First Generation Protease Inhibitors for Hepatitis C Markedly Impairs Function of Neutrophil Granulocytes

First-generation HCV protease inhibitors represent a milestone in antiviral therapy for chronic hepatitis C infection (CHC), but substantially increased rates of viral clearance are offset by increased rates of infection and infection-associated deaths, especially of patients with advanced liver disease. We aimed to assess whether first generation protease inhibitors interfere with neutrophil function. We included 108 consecutive, retrospective CHC patients and 44 consecutive, prospective CHC patients who were treated with peginterferon and ribavirin with or without protease inhibitors according to the guidelines in the period of November 2012 to June 2015. 33 healthy volunteers served as controls. Infection data were evaluated in all patients. Neutrophil phagocytosis, oxidative burst, elastase and diamine oxidase levels during 12 weeks of triple (n = 23) or dual therapy (n = 21) were studied in the prospective part. In the retro- and prospective cohorts patients experiencing clinically relevant infections were significantly more frequent during protease inhibitor therapy (31% and 26%) than during therapy with peginterferon and ribavirin (13% and 0%). Neutrophil phagocytosis decreased to 40% of baseline with addition of protease inhibitors to P/R but recovered 6 months after end of treatment. Protease inhibitors also seemed to reduce serum elastase levels but did not impact on gut permeability. Impaired neutrophil function during triple therapy with first generation HCV protease inhibitors may explain the high infection rate associated to these treatments and be of relevance for treatment success and patient survival.

Effectiveness of Simeprevir Plus Sofosbuvir, With or Without Ribavirin, in Real-World Patients With HCV Genotype 1 Infection

BACKGROUND & AIMS

The interferon-free regimen of simeprevir plus sofosbuvir was recommended by professional guidelines for certain patients with hepatitis C virus (HCV) genotype 1 infection based on the findings of a phase 2 trial. We aimed to evaluate the safety and efficacy of this regimen in clinical practice settings in North America.

METHODS

We collected demographic, clinical, and virologic data, as well as reports of adverse outcomes, from sequential participants in HCV-TARGET--a prospective observational cohort study of patients undergoing HCV treatment in routine clinical care settings. From January through October 2014, there were 836 patients with HCV genotype 1 infection who began 12 weeks of treatment with simeprevir plus sofosbuvir (treatment duration of up to 16 weeks); 169 of these patients received ribavirin. Most patients were male (61%), Caucasian (76%), or black (13%); 59% had cirrhosis. Most patients had failed prior treatment with peginterferon and ribavirin without (46%) or with telaprevir or boceprevir (12%). The primary outcome was sustained virologic response (SVR), defined as the level of HCV RNA below quantification at least 64 days after the end of treatment (beginning of week 12 after treatment--a 2-week window). Logistic regression models with inverse probability weights were constructed to adjust for baseline covariates and potential selection bias.

RESULTS

The overall SVR rate was 84% (675 of 802 patients, 95% confidence interval, 81%-87%). Model-adjusted estimates indicate patients with cirrhosis, prior decompensation, and previous protease inhibitor treatments were less likely to achieve an SVR. The addition of ribavirin had no detectable effects on SVR. The most common adverse events were fatigue, headache, nausea, rash, and insomnia. Serious adverse events and treatment discontinuation occurred in only 5% and 3% of participants, respectively.

CONCLUSIONS

In a large prospective observational cohort study, a 12-week regimen of simeprevir plus sofosbuvir was associated with high rates of SVR and infrequent treatment discontinuation. ClinicalTrials.gov: NCT01474811.

Boceprevir-Based Triple Antiviral Therapy for Chronic Hepatitis C Virus Infection in Kidney-Transplant Candidates

Background. There are few data on the combination of (pegylated-) interferon- (Peg-IFN-) α, ribavirin, and first-generation direct-acting antiviral agents (DAAs). Our aim was to describe the efficacy and safety of Peg-IFN-α, ribavirin, and boceprevir in hemodialysis patients. Patients. Six hemodialysis patients, chronically infected by genotype-1 HCV, were given Peg-IFN-α (135 µg/week), ribavirin (200 mg/d), and boceprevir (2400 mg/d) for 48 weeks. Results. At initiation of antiviral therapy, median viral concentration was 5.68 (3.78–6.55) log IU/mL. HCV RNA was undetectable in four of the six patients at week 4 and in all patients at week 24. A breakthrough was observed in two patients between weeks 24 and 48, and a third patient stopped antiviral therapy between weeks 24 and 48 because of severe peripheral neuropathy. At week 48, HCV RNA was undetectable in three patients. Of these, two patients relapsed within a month after antiviral therapy was stopped. Hence, only one patient had a sustained virological response; he was a previous partial responder. Overall, anemia was the main side effect. Conclusion. A triple antiviral therapy based on Peg-IFN-α, ribavirin, and boceprevir is not optimal at treating hemodialysis patients with chronic HCV infection. Studies using new-generation drugs are required in this setting.

Cutaneous Adverse Events in Chronic Hepatitis C Patients Treated With New Direct-Acting Antivirals

Background:

Direct-acting antivirals (DAAs) are known to present with additional dermatological events over pegylated-interferon/ribavirin (Peg-IFN/RBV).

Objective:

A systematic review and meta-analysis was conducted to assess the incidence/risk of cutaneous adverse events (AEs) for simeprevir, sofosbuvir, ABT450/r-ombitasvir, dasabuvir, ledipasvir, daclatasvir, and asunaprevir.

Methods:

The databases searched included PubMed, Clinicaltrials.gov, and Clinicaloptions.com. Data on telaprevir and boceprevir were obtained from a previous study.

Results:

The incidences of cutaneous AEs were 34.3% (95% CI 18.4%-54.8%) for the old DAAs + Peg-IFN/RBV, 22.0% (95% CI 17.9%-26.8%) for the new DAAs + Peg-IFN/RBV, 9.8% (95% CI 8.6%-11.2%) for the DAAs + RBV, and 3.8% (95% CI 2.4%-6.1%) for DAAs only. Simeprevir + Peg-IFN/RBV was associated with an increased relative risk over Peg-IFN/RBV; RR = 1.319 (95% CI 1.026-1.697).

Conclusion:

Dermatological events are still an important issue for many of the new DAAs. Appropriate monitoring, management, and patient education are needed to minimize AEs and achieve HCV cure.

Treatment optimization of naïve HCV-1 patients using IL28B, RVR and fibrosis stage

The treatment of patients with HCV genotype 1 is quickly changing. The clinician could optimize the selection of patients who may benefit from standard therapy with pegylated-interferon and ribavirin instead of more expensive new combinations with the directly acting antivirals. We retrospectively examined in our cohort of 232 patients with genotype 1 infection the role of interleukin 28B (both rs8099917 and rs12979860), fibrosis stage and rapid virological response. Global SVR in TT/CC patients was 88.3% (98% in F0-F1, 80% in F2-F3); in TT/TC was 68.2 (85% in F0-F1, 71.4% in F2-F3). Rapid virological response was related to rs12979860 CC genotype but is not useful to predict the virological response in TG/GG patients at rs8099917. The standard dual therapy may be successfully administered in all TT/CC and TT/TC patients without F4 fibrosis score. Conversely, patients with TG/CC or GG/CC genotypes should be treated with other therapeutic options.

Telaprevir experience from Turkey

BACKGROUND

In patients with chronic hepatitis C, triple drug regimens containing a protease inhibitor, peginterferon and ribavirin were found to significantly increase sustained virologic response rates compared to dual drug regimen containing pegylated interferon and ribavirin, especially in genotype 1.

OBJECTIVES

In Turkey, telaprevir has been used since March 2013. We aimed to evaluate results of patients with chronic hepatitis C treated with telaprevir, peginterferon and ribavirin.

PATIENTS AND METHODS

We evaluated 28 patients with genotype 1 chronic hepatitis C infection treated with triple drug regimen containing telaprevir, in three medical centers in Turkey, retrospectively. Demographic data of patients, treatment indications, adverse events and outcomes were recorded.

RESULTS

Of 28 patients intended to treat, 25 (89.2%) patients completed the treatment. Overall, 21 (82.1%) patients had relapse and five patients were non-responder. Regarding the treatment outcomes of Telaprevir based regimen, 20/26 patients achieved sustained virological response. Pruritus, rash, dysgeusia, anorectal discomfort and anemia were main adverse effects. Blood transfusion and ribavirin dose reduction required for 7 and 11 patients, respectively. Due to several adverse effects, 10 patients were hospitalized.

CONCLUSIONS

Although more frequent and severe adverse effects, telaprevir has been promising for patients with treatment-experienced hepatitis C.

Boceprevir and telaprevir for chronic genotype 1 hepatitis C virus infection. A systematic review and meta-analysis

BACKGROUND

Treatment of hepatitis C virus (HCV) infection with newer direct-acting antivirals is unrealistic in some countries because of the lack of availability.

AIM

Assess benefits and harms of boceprevir (BOC) and telaprevir (TLV) in treatment of genotype 1 HCV infection, and identifying subgroups with most benefit.

MATERIAL AND METHODS

Search from 2009-2013 in PubMed, EMBASE, and "gray literature" of published and unpublished randomized trials reporting sustained viral response (SVR) or adverse events (AE) with BOC or TLV + pegylated interferon and ribavirin (PR) in HCV-infected patients; cohorts or case reports for comparison protease inhibitors (PI), evaluation of predictors of SVR, and resistant variants. Cochrane guidelines were applied. Comparisons between PI + PR vs. PR were performed. Main outcomes were expressed as risk-ratios with 95% CIs. Meta-regression and trial sequential analysis were performed.

RESULTS

33 studies (10,525 patients) were analyzed. SVR was higher for PI + PR (RR, 2.05; 95% CI 1.70-2.48). In meta-regression, previously treated patients exhibited greater benefit from PI + PR (RR, 3.47; 95% CI, 2.78-4.33). AE were higher with PI + PR (RR, 1.01; 95% CI, 1-1.03; NNH 77.59), also the discontinuation rate (RR, 1.69; 95% CI, 1.36-2.10, NNH, 18). Predictors of SVR were IL-28 TT, nonblack race, low viral load, age, no cirrhosis, statin use, undetectable viral load at the first anemia episode and at week 2 of treatment, and low IL-6 levels. In conclusion SVR was higher in patients treated with PIs, patients previously exposed to PR showed superior response rates. Specific predictors will determine the best candidates for treatments that will offer real-life therapeutic alternatives.

Recent advances and future directions in the management of hepatitis C infections

Current estimates indicate that the hepatitis C virus is the leading cause of death in the United States with infection rates steadily increasing. Successful treatment is made difficult by the presence of various host, virus, and treatment-related factors, warranting the development of new approaches to combat the silent epidemic. The addition of telaprevir and boceprevir to the pharmacotherapeutic arsenal drastically improved success rates in genotype 1 infected patients, but rapid development of resistance mechanisms, increases in adverse effects, and a low spectrum activity proved to be barriers to efficacious treatment. In late 2013, two new agents were approved - sofosbuvir and simeprevir - that have higher barriers to resistance, favorable safety profiles, and profoundly improved success rates; however higher costs associated with the new medications could limit their wider utilization. Further strategies to combat the virus are under development, ranging from interferon-free regimens as well as prophylactic and therapeutic vaccines to applications of nanotechnology, helping us get closer to improved treatment of patients infected with hepatitis C.

Lipid nanoparticles as carriers for RNAi against viral infections: current status and future perspectives

The efforts made to develop RNAi-based therapies have led to productive research in the field of infections in humans, such as hepatitis C virus (HCV), hepatitis B virus (HBV), human immunodeficiency virus (HIV), human cytomegalovirus (HCMV), herpetic keratitis, human papillomavirus, or influenza virus. Naked RNAi molecules are rapidly digested by nucleases in the serum, and due to their negative surface charge, entry into the cell cytoplasm is also hampered, which makes necessary the use of delivery systems to exploit the full potential of RNAi therapeutics. Lipid nanoparticles (LNP) represent one of the most widely used delivery systems for in vivo application of RNAi due to their relative safety and simplicity of production, joint with the enhanced payload and protection of encapsulated RNAs. Moreover, LNP may be functionalized to reach target cells, and they may be used to combine RNAi molecules with conventional drug substances to reduce resistance or improve efficiency. This review features the current application of LNP in RNAi mediated therapy against viral infections and aims to explore possible future lines of action in this field.