***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To determine whether lamivudine or interferon-alpha ( IFN-alpha ) is the more successful treatment for chronic hepatitis B given a fixed drug budget . STUDY DESIGN A decision-tree model of 1 year . PATIENTS AND METHODS Average wholesale prices were used to estimate drug costs . A fixed drug budget of $ 558,910 , sufficient to treat 100 patients with IFN-alpha  , was assumed . Clinical data were taken from r and omized controlled trials . The outcome measures used were hepatitis B " e " antigen ( HBeAg ) seroconversion rates and rates of progression to cirrhosis . RESULTS The analysis showed that given the fixed drug budget , 353 patients could be treated with lamivudine  , result ing in an expected 62 HBeAg seroconversions  , with 6 patients progressing to cirrhosis . Given the same drug budget , 100 patients could be treated with IFN-alpha , leaving 253 patients untreated . This treatment scenario would result in an expected 32 HBeAg seroconversions , with 28 patients progressing to cirrhosis . Compared with no treatment , the costs per additional HBeAg seroconversion obtained were $ 12,703 for lamivudine and $ 39,922 for IFN-alpha . In addition , each case of cirrhosis avoided through lamivudine treatment result ed in significant annual cost savings .  Lamivudine therapy also provided additional clinical benefits ( e.g. , normalization of alanine transaminase levels , reduction in hepatitis B virus DNA levels , improvement in liver histology ) to patients who do not seroconvert . CONCLUSION From the perspective of a third-party payer with a fixed drug budget , lamivudine is more cost-effective therapy than IFN-alpha for the treatment of chronic hepatitis BACKGROUND As new treatment options for chronic hepatitis B virus ( HBV ) become available , evaluations of cost-effectiveness become important . Entecavir is a deoxyguanine nucleoside analogue approved by the U.S. Food and Drug Administration in March 2005 for HBV infection in adults with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases ( alanine aminotransferase or aspartate aminotransferase ) or histologically active disease .  Entecavir has demonstrated greater suppression of viral replication compared with lamivudine , but also has a relatively higher drug acquisition cost in the United States . OBJECTIVE To estimate the long-term health and economic impact of treating HBV with entecavir versus lamivudine in patients who are positive for hepatitis B e antigen ( HBeAg ) based on the efficacy and safety results of the Phase 3 , double-blind , r and omized controlled trial , Benefits of Entecavir for Hepatitis B Liver Disease ( BEHoLD ) . METHODS A decision tree model was developed to evaluate the cost-effectiveness of entecavir compared with lamuvidine in suppressing HBV DNA to an undetectable level . Risks for compensated cirrhosis ( CC ) , decompensated cirrhosis ( DC ) , and hepatocellular carcinoma ( HCC ) were derived from the published Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer-Hepatitis B Virus ( REVEAL-HBV , 2006 ) study , a longitudinal ( mean follow-up : 11.4 years ) cohort study of community residents who were seropositive for the hepatitis B surface antigen ; 85 % of REVEAL-HBV participants were HBeAg-negative . To estimate future risks of CC , DC , and HCC , the REVEAL-HBV study 's multivariate-adjusted relative risks of CC , DC , and HCC for 5 HBV DNA ( viral load level ) categories were applied to posttreatment HBV DNA levels obtained from the BEHoLD trial of 709 HBeAg-positive HBV patients treated with entecavir ( n = 354 ) or lamivudine ( n = 355 ) .  Entecavir and lamivudine were assigned annual costs of $ 7,365 and $ 2,604 , respectively , based on the wholesale acquisition cost . Life expectancy for DC and HCC was estimated by the declining exponential approximation of life expectancy method . Other model parameter values , such as utilities and event medical costs , were derived from published sources . The joint uncertainty of projected event time distribution and treatment failure rates beyond the trial period were considered using probabilistic sensitivity analyses ( PSA ) with 1,000 replicates . The analytic perspective was that of a U.S. third-party payer responsible for all direct health care expenditures . RESULTS In the BEHoLD clinical trial ( AI463022 ) , subjects were predominantly male ( 75 % ) , Asian ( 57 % ) , or white ( 40 % ) with a mean age of 35 years .  Entecavir was superior to lamivudine in the proportion of subjects who achieved undetectable HBV DNA ( < 300 copies per mL ) by polymerase- chain reaction assay at week 48 ( 69.1 % vs. 39.8 % , respectively ) ( P < 0.001 ) . In the REVEAL-HBV study after statistical adjustment for age , gender , cigarette smoking , and alcohol consumption , rates of CC , DC , and HCC were associated with higher HBV DNA levels ( e.g. , compared with the reference category [ < 300 copies per mL ] , adjusted hazard ratios for HCC were 1.2 , 2.9 , 9.5 , and 15.2 for serum HBV DNA levels of 300 - 9,999 , 10,000 - 99,999 , 100,000 - 999,999 , and e > or = 1 million copies per mL , respectively ) . In the reference case , for a hypothetical cohort of 1,000 HBV patients aged 35 years , 52 weeks of entecavir treatment compared with lamivudine treatment avoided 71 cases of CC , 8 DC cases , and 42 HCC cases within 10 years , result ing in a 0.728 quality -adjusted life-year ( QALY ) gain at an incremental cost of $ 2,350 , with a 3 % annual discount . The incremental cost of using entecavir was $ 3,230 per QALY gained ( 95 % confidence interval [ CI ] , $ 2,312-$4,528 ) , with 99.3 % of PSA-derived estimates below $ 5,000 per QALY . Results were robust and most sensitive to efficacy , drug cost , and treatment duration . CONCLUSIONS Assuming that ( 1 ) the efficacy of entecavir after 1 year is sustainable and ( 2 ) liver disease risk levels from the REVEAL-HBV study population ( a primarily HBeAg-negative group ) adequately represent risk for a treated HBeAg-positive patient group , entecavir given for up to 10 years would be highly cost-effective in HBeAg-positive patients Background Peginterferon & agr;-2a ( 40 kDa ) , a new treatment for chronic hepatitis B , produces seroconversion within 48 weeks in approximately 32 % of HBeAg-positive patients . Over a defined treatment duration it offers improved efficacy over lamivudine , but at higher cost . We assessed the clinical outcomes and costs , from the perspective of the UK National Health Service , of 48 weeks of peginterferon & agr;-2a ( 40 kDa ) vs. 4 years of lamivudine . Methods Cost-effectiveness was analysed using a state-transition Markov model simulating HBeAg-positive chronic hepatitis B natural history . Efficacy data were obtained from a large r and omized trial comparing peginterferon & agr;-2a ( 40 kDa ) with lamivudine over 48 weeks . Use of adefovir salvage treatment for lamivudine-resistant patients was also evaluated . Long-term lamivudine efficacy , treatment durability , disease progression , cost , and quality -of-life estimates were derived from the literature . One-way and probabilistic sensitivity analyses evaluated uncertainty . Results Treatment with peginterferon & agr;-2a ( 40 kDa ) for 48 weeks result ed in higher discounted total healthcare costs ( £ 3100 ) , but an increase of 0.3 discounted quality -adjusted life years compared with long-term lamivudine , giving an incremental cost-effectiveness ratio of £ 10 400 per quality -adjusted life year gained ( £ 8300–£15 400 in one-way sensitivity analyses ) . The cost-effectiveness acceptability curve showed intervention was below the £ 30 000/QALY threshold in over 95 % of the simulations . When adefovir was included for patients with lamivudine resistance , peginterferon & agr;-2a ( 40 kDa ) had an incremental cost of £ 6100/QALY gained . Conclusions Treatment with peginterferon & agr;-2a ( 40 kDa ) for a defined duration of 48 weeks , although more expensive than lamivudine therapy , provides improvement in health outcomes , with a cost-effectiveness ratio well below the current UK cost-effectiveness threshold Hepatitis B virus infection is an important public-health issue . Chronic patients have a higher risk of death due to complications , which increases health-care expenses in . Cost-effectiveness analysis of entecavir ( ETV ) versus lamivudine ( LVD ) for treatment of chronic hepatitis B , in e antigen (AgHBe)-positive and negative patients , based on two phase 3 , controlled and r and omized studies . A decision analysis model was developed , using the following endpoints : cost per patient with undetectable viral load and cost per quality life year ( QALY ) gained . Risks for complications ( compensated or decompensated cirrhosis and hepatocellular carcinoma ) were based on the cohort study REVEAL , published in 2006 . The REVEAL parameters were applied to the results of the viral load levels obtained from the clinical assay data . The complication costs were based on a study of the disease cost conducted in Brazil , in 2005 . The cost data were obtained predominantly from Sistema Unico de Saúde [ SUS - Brazilian public health system ] payment tables and drug price lists . The utility data were obtained from literature and life expectancy information was based on IBGE data . The analysis perspective was that of SUS . A discount rate of 3 % per year was used . For the horizon of time of 10 years , the ETV had an incremental cost of approximately two million Brazilian Reais ( R$ ) compared to LVD . Reducing the number of complications ,  ETV treatment reduced costs by around 3 million , reducing final costs by 1 million , for AgHBe-positive patients .  ETV also reduced the incremental cost per QALY gained .  ETV was found to be the most cost-effective alternative for AgHBe-positive and negative patients Context Because current treatment options for chronic hepatitis B virus ( HBV ) infection have varying effects and costs , choosing among them is often difficult . Contribution Using a third-party payer perspective and lifetime horizon , this costutility analysis found that monotherapy with interferon but not lamivudine or adefovir was cost-effective . A salvage strategy that used adefovir only in case of lamivudine-associated viral resistance also seemed cost-effective . Caution s The findings apply only to patients with persistently elevated aminotransferase levels and no cirrhosis . The authors did not model the cost-effectiveness of nucleoside analogue salvage after interferon therapy failure . The Editors Chronic hepatitis B virus ( HBV ) infection is a prevalent and expensive condition , affecting 350 million people worldwide and 1.25 million people in the United States ( 1 ) at a cost of more than $ 700 million annually ( 2 ) . Chronic HBV infection can progress to cirrhosis , liver failure , and hepatocellular carcinoma and is a major cause of morbidity and mortality ( 1 , 3 ) . Traditional therapy for chronic HBV infection with either interferon-2b ( interferon ) or lamivudine is difficult and has limited long-term efficacy ( 4 ) . Interferon has clinical ly significant side effects and results in durable virologic response in only 15 % to 30 % of patients ( 5 - 8 ) . Lamivudine is easy to administer and is associated with minimal side effects ( 9 - 11 ) , but it has a higher rate of viral resistance ( 12 ) , lower durable response rate ( 9 - 11 ) , and greater need for prolonged therapy ( 9 , 11 ) compared with interferon . The efficacy of both interferon and lamivudine is even more limited in patients with hepatitis B e antigennegative ( HBeAg-negative ) disease ( 4 ) . This burgeoning population now accounts for more than half of patients with HBV in the United States ( 13 ) and up to 80 % of patients with HBV in Asia ( 14 , 15 ) . Data from 2 r and omized , controlled trials indicate that adefovir is efficacious in HBeAg-positive and HBeAg-negative patients ( 16 , 17 ) . Adefovir has a low risk for side effects and viral resistance ( 18 ) compared with interferon and lamivudine , but it is more expensive ( 19 ) . Therefore , the improved therapeutic benefits of adefovir in chronic HBV infection may offset its increased cost compared with 
    Output:
    
We consider that the available evidence suggests that to give antiviral treatment for chronic hepatitis B  is a cost-effective intervention for many health systems , including ours .
It has varying indexes of cost-effectiveness according to the evaluated regimens .