Cost-effectiveness of Ombitasvir/Paritaprevir/Ritonavir, Dasabuvir+Ribavirin for US Post-Liver Transplant Recurrent Genotype 1 HCV

Viral proteases as therapeutic targets

Some medically important viruses-including retroviruses, flaviviruses, coronaviruses, and herpesviruses-code for a protease, which is indispensable for viral maturation and pathogenesis. Viral protease inhibitors have become an important class of antiviral drugs. Development of the first-in-class viral protease inhibitor saquinavir, which targets HIV protease, started a new era in the treatment of chronic viral diseases. Combining several drugs that target different steps of the viral life cycle enables use of lower doses of individual drugs (and thereby reduction of potential side effects, which frequently occur during long term therapy) and reduces drug-resistance development. Currently, several HIV and HCV protease inhibitors are routinely used in clinical practice. In addition, a drug including an inhibitor of SARS-CoV-2 main protease, nirmatrelvir (co-administered with a pharmacokinetic booster ritonavir as Paxlovid®), was recently authorized for emergency use. This review summarizes the basic features of the proteases of human immunodeficiency virus (HIV), hepatitis C virus (HCV), and SARS-CoV-2 and discusses the properties of their inhibitors in clinical use, as well as development of compounds in the pipeline.

Cost-effectiveness of second-generation direct-acting antiviral agents in chronic HCV infection: a systematic literature review

BACKGROUND

Our objectives were to review the economic modelling methods and cost-effectiveness of second-generation direct-acting antiviral agents for the treatment of chronic HCV infection.

METHODS

A systematic literature search was performed in February 2017 using Scopus and OVID to review relevant publications between 2011 to present. Two independent reviewers screened potential papers.

RESULTS

The database search resulted in a total of 1,536 articles; after deduplication, title/abstract and full text screening, 67 studies were included for qualitative analysis. The vast majority of studies were conducted in high-income countries (n=59) and used Markov-based modelling techniques (n=60). Most of the analyses utilized long-term time horizons; 58 studies calculated lifetime costs and outcomes. The examined treatments were heterogenic among the studies; seven analyses did not directly evaluate treatments (just with screening or genotype testing). The examined treatments (n=60) were either dominant (23%), or cost-effective at base case (57%) or in given subgroups (18%). Only one (2%) study reported that the assessed treatment was not cost-effective with the given setting and price.

CONCLUSIONS

Despite their high initial therapeutic costs, second-generation direct-acting antiviral agents were found to be cost-effective to treat chronic HCV infection. Studies were predominantly conducted in higher income countries, although we have limited information on cost-effectiveness in low- and middle-income countries, where assessment of cost-effectiveness is even more essential due to more limited health-care resources and potentially higher public health burden due to unsafe medical interventions.

Elimination of Hepatitis C in Liver Transplant Recipients

Background and Aims: Recurrent hepatitis C (HCV) disease in liver transplant (LT) recipients is associated with significant morbidity and mortality. With the availability of noninterferon-based therapy, eliminating HCV may be achievable in LT recipients. Methods: We studied all consecutive recipients who underwent LT at the University of California Los Angeles between January 2005 and June 2017. We collected data on date of transplant and last follow-up, as well as laboratory values. We also recorded type and timing of antiviral therapy relative to LT. Analyses were performed to assess the proportion of LT recipients who are viremic after transplant. Results: Six hundred thirty-four patients underwent LT with a diagnosis of HCV. There was a statistically significant trend for patients to be cured before (p < 0.001) and after liver transplantation (p < 0.001) for the study period of 2014 to 2016 relative to 2005 and 2013, respectively. Of the 634 recipients eligible for therapy, 8% and 74% were treated within 12 months of transplant for the study periods 2005 to 2013 and 2014 to 2016, respectively. There was a significant decrease between the two study periods in the proportion of patients undergoing re-LT 1 year after the original LT: 5.5% (n = 28/510) and 1.5% (n = 2/124) respectively for study periods 2005 to 2013 and 2014 to 2016 respectively (p = 0.011). Conclusions: The proportion of LT recipients who are viremic has decreased over time. Eliminating HCV in LT recipients is feasible after the introduction of direct-acting agents. Curing HCV should translate to improved clinical outcomes in LT recipients who were transplanted for HCV infection with longer follow-up. Preliminary results suggest the decreased need for transplant in the direct-acting agents era.

Before or After Transplantation? A Review of the Cost Effectiveness of Treating Waitlisted Patients With Hepatitis C

All patients with chronic hepatitis C virus (HCV) infections can and should be treated. Though highly effective direct-acting antiviral therapies are costly, the price of a cure is a 1-time investment that is outweighed by future benefits. For clinicians caring for patients requiring liver transplant, the key question relates to the timing of treatment: before or after liver transplantation? On 1 hand, treating HCV often improves our patients' model for end-stage liver disease (MELD) score, decreasing costs, and potentially improving longevity by reducing our patients' risk of death and transplantation. On the other hand, there is a concern that the cured patient with decompensated cirrhosis will find themselves in "MELD purgatory" with nonprogressive liver disease but a poor quality of life. At the same time, some patients, such as those with hepatocellular carcinoma, will require liver transplant irrespective of their MELD meaning that pretransplant therapy cannot reduce costs in such settings. These important tradeoffs are often difficult reconcile for clinicians who care for patients awaiting liver transplant. Fortunately, guidance for navigating these competing concerns can be obtained from cost-effectiveness analyses. Herein, we review the available data on this approach to HCV therapy before or after liver transplant.

The Optimal Timing of Hepatitis C Therapy in Transplant Eligible Patients With Child B and C Cirrhosis: A Cost-Effectiveness Analysis

BACKGROUND

Ledipasvir (LDV)/sofosbuvir (SOF) has demonstrated high efficacy, safety, and tolerability in hepatitis C virus (HCV)-infected patients. There is limited data, however, regarding the optimal timing of therapy in the context of possible liver transplantation (LT).

METHODS

We compared the cost-effectiveness of 12 weeks of HCV therapy before or after LT or nontreatment using a decision analytical microsimulation state-transition model for a simulated cohort of 10 000 patients with HCV Genotype 1 or 4 with Child B or C cirrhosis. All model parameters regarding the efficacy of therapy, adverse events and the effect of therapy on changes in model for end-stage liver disease (MELD) scores were derived from the SOLAR-1 and 2 trials. The simulations were repeated with 10 000 samples from the parameter distributions. The primary outcome was cost (2014 US dollars) per quality adjusted life year.

RESULTS

Treatment before LT yielded more quality-adjusted life year for less money than treatment after LT or nontreatment. Treatment before LT was cost-effective in 100% of samples at a willingness-to-pay threshold of US $100 000 in the base-case and when the analysis was restricted to Child B alone, Child C, or MELD > 15. Treatment before transplant was not cost-effective when MELD was 6-10. In sensitivity analyses, the MELD after which treatment before transplant was cost-effective was 13 and the maximum cost of LDV/SOF therapy at which treatment before LT is cost-effective is US $177 381.

CONCLUSIONS

From a societal perspective, HCV therapy using LDV/SOF with ribavirin before LT is the most cost-effective strategy for patients with decompensated cirrhosis and MELD score greater than 13.

Effectiveness of Ledipasvir/Sofosbuvir with/without Ribavarin in Liver Transplant Recipients with Hepatitis C

Background and Aims: Recurrent infection of hepatitis C virus (HCV) in liver transplant (LT) recipients is universal and associated with significant morbidity and mortality. Methods: We retrospectively evaluated the safety and efficacy of ledipasvir/sofosbuvir with and without ribavirin in LT recipients with recurrent genotype 1 hepatitis C. Results: Eighty-five LT recipients were treated for recurrent HCV with ledipasvir/sofosbuvirwith and without ribavirin for 12 or 24 weeks. The mean (± standard deviation [SD]) time from LT to treatment initiation was 68 (±71) months. The mean (± SD) age of the cohort was 63 (±8.6) years old. Most recipients were male (70%). Baseline alanine transaminase, total bilirubin, and HCV ribonucleic acid (RNA) values (± SD) were 76.8 (±126) mg/dL, 0.8 (±1.3) U/L, and 8,010,421.9 (±12,420,985) IU/mL, respectively. Five of 43 recipients who were treated with ribavirin required drug cessation due to side effects, with 4 of those being anemia complications. No recipient discontinued the ledipasvir/sofosbuvir. Eighty-one percent of recipients had undetectable viral levels at 4 weeks after starting therapy, and all recipients had complete viral suppression at the end of therapy. The sustained viral response at 12 weeks after completion of therapy was 94%. Conclusion : Ledipasvir and sofosbuvir with and without ribavirin therapy is an effective and well-tolerated interferon-free treatment for recurrent HCV infection after LT. Anemia is not uncommon in LT recipients receiving ribavirin.

Effectiveness and safety of ombitasvir, paritaprevir, ritonavir ± dasabuvir ± ribavirin: An early access programme for Spanish patients with genotype 1/4 chronic hepatitis C virus infection

Over the last 5 years, therapies for hepatitis C virus (HCV) infection have improved significantly, achieving sustained virologic response (SVR) rates of up to 100% in clinical trials in patients with HCV genotype 1. We investigated the effectiveness and safety of ombitasvir/paritaprevir/ritonavir±dasabuvir in an early access programme. This was a retrospective, multicentre, national study that included 291 treatment-naïve and treatment-experienced patients with genotype 1 or 4 HCV infection. Most patients (65.3%) were male, and the mean age was 57.5 years. The mean baseline viral load was 6.1 log, 69.8% had HCV 1b genotype, 72.9% had cirrhosis and 34.7% were treatment-naïve. SVR at 12 weeks posttreatment was 96.2%. Four patients had virological failure (1.4%), one leading to discontinuation. There were no statistical differences in virological response according to genotype or liver fibrosis. Thirty patients experienced serious adverse events (SAEs) (10.3%), leading to discontinuation in six cases. Hepatic decompensation was observed in five patients. Four patients died during treatment or follow-up, three of them directly related to liver failure. Multivariate analyses showed a decreased probability of achieving SVR associated with baseline albumin, bilirubin and Child-Pugh score B, and a greater probability of developing SAEs related to age and albumin. This combined therapy was highly effective in clinical practice with an acceptable safety profile and low rates of treatment discontinuation.

Cost-Effectiveness of Treatments for Genotype 1 Hepatitis C Virus Infection in non-VA and VA Populations

Background: Chronic hepatitis C viral (HCV) infection affects millions of Americans. Health care systems face complex choices between highly efficacious, costly treatments. This study assessed the cost-effectiveness of treatments for chronic, genotype 1 HCV monoinfected, treatment-naïve individuals in the Department of Veterans Affairs (VA) and general US health care systems. Methods: The study used a decision-analytic Markov model, employing appropriate payer perspectives and time horizons, and discounting benefits and costs at 3% annually. Interventions included the following: sofosbuvir/ledipasvir (SOF-LDV); ombitasvir/paritaprevir/ritonavir/dasabuvir (3D); sofosbuvir/simeprevir (SOF-SMV); sofosbuvir/pegylated interferon/ribavirin (SOF-RBV-PEG); boceprevir/pegylated interferon/ribavirin (BOC-RBV-PEG); and pegylated interferon/ribavirin (PEG-RBV). Outcomes were sustained virologic response (SVR), advanced liver disease, costs, quality adjusted life years (QALYs), and incremental cost-effectiveness. Results: SOF-LDV and 3D achieve high SVR rates, reducing advanced liver disease (>20% relative to no treatment), and increasing QALYs by >2 years per person. For the non-VA population, at current prices ($5040 per week for SOF-LDV; $4796 per week for 3D), SOF-LDV’s lifetime cost ($293,370) is $18,000 lower than 3D’s because of its shorter duration in subgroups. SOF-LDV costs $17,100 per QALY gained relative to no treatment. 3D costs $208,000 per QALY gained relative to SOF-LDV. Both dominate other treatments and are even more cost-effective for the VA, though VA aggregate treatment costs still exceed $4 billion at SOF-LDV prices of $3308 per week. Drug prices strongly determine relative cost-effectiveness for SOF-LDV and 3D; with price reductions of 20% to 30% depending on health system, 3D could be cost-effective relative to SOF-LDV. We currently lack head-to-head regimen effectiveness trials. Conclusions: New HCV treatments are cost-effective in multiple health care systems if trial-estimated efficacy is achieved in practice, though, at current prices, total expenditures could present substantial challenges.