***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: To evaluate the efficacy of recombinant interferon alpha-2b in the treatment of patients with acute post-transfusion hepatitis C , a r and omized controlled trial was conducted in 33 acute post-transfusion hepatitis C patients ; 16 patients received 3 million units of subcutaneously injected recombinant interferon alpha-2b  3 times a week for 3 months and 17 patients without specific treatment were used as controls . At the end of the interferon treatment , 13 ( 81 % ) patients in the interferon-treated group normalized serum alanine aminotransferase compared with only six ( 35 % ) patients in the control group ( p < 0.01 ) . One year after completion of the interferon treatment , nine ( 56 % ) patients in the interferon-treated group and six ( 38 % ) patients in the control group normalized serum alanine aminotransferase ( p = 0.35 ) . Serum HCV-RNA measured by reverse transcription-polymerase chain reaction was positive in all patients at the time of enrollment and then became undetectable in 13 ( 81 % ) patients in the interferon-treated group and two ( 12 % ) patients in the control group at the end of interferon treatment ( p < 0.001 ) . One year after completion of the interferon treatment , seven ( 44 % ) patients in the interferon-treated group and two ( 13 % ) patients in the control group had persistent undetectable serum HCV-RNA ( p = 0.08 ) . Using a logistic regression model , the lower pretreatment level of serum HCV-RNA measured by quantitative branched DNA signal amplification assay was the only predictor for a favorable response to the interferon treatment in acute hepatitis C patients . ( ABSTRACT TRUNCATED AT 250 WORDS OBJECTIVES To analyze sources search ed in Cochrane review s , to determine the proportion of trials included in review s that are indexed in major data bases , and to compare the quality of these trials with those from other sources . METHODS All new systematic review s in the Cochrane Library , Issue1 2001 , that were restricted to r and omized controlled trials ( RCTs ) or quasi- RCTs were selected . The sources search ed in the review s were recorded , and the trials included were checked to see whether they were indexed in four major data bases . Trials not indexed were checked to determine how they could be identified . The quality of trials found in major data bases was compared with those found from other sources . RESULTS The range in the number of data bases search ed per review ranged between one and twenty-seven . The proportion of the trials in the four data bases were Cochrane Controlled Trials Register = 78.5 % , MEDLINE = 68.8 % , Embase = 65.0 % , and Science/Social Sciences Citation Index = 60.7 % . Search ing another twenty-six data bases after Cochrane Controlled Trials Register ( CCTR ) , MEDLINE , and Embase only found 2.4 % additional trials . There was no significant difference between trials found in the CCTR , MEDLINE , and Embase compared with other trials , with respect to adequate allocation concealment or sample size . CONCLUSIONS There was a large variation between review s in the exhaustiveness of the literature search es . CCTR was the single best source of RCTs . Additional data base search ing retrieved only a small percentage of extra trials . Contacting authors and manufacturers to find unpublished trials appeared to be a more effective method of obtaining the additional better quality trials BACKGROUND There is an international epidemic of hepatitis C virus ( HCV ) infection among human immunodeficiency virus (HIV)-infected men who have sex with men .  Sustained virologic response ( SVR ) rates with pegylated interferon and ribavirin treatment are higher in these men during acute HCV than during chronic HCV , but treatment is still lengthy and SVR rates are suboptimal . METHODS We performed a pilot study of combination therapy with telaprevir , pegylated interferon , and ribavirin in acute genotype 1 HCV infection in HIV-infected men . Men who were treated prior to the availability of , or ineligible for , telaprevir were the comparator group . The primary endpoint was SVR12 , defined as an HCV viral load < 5 IU/mL at least 12 weeks after completing treatment . RESULTS In the telaprevir group , 84 % ( 16/19 ) of men achieved SVR12 vs 63 % ( 30/48 ) in the comparator group . Among men with SVR , median time to undetectable viral load was week 2 in the telaprevir group vs week 4 in the comparator group , and 94 % vs 53 % had undetectable viral loads at week 4 . Most patients ( 81 % ) who achieved SVR in the telaprevir group received ≤12 weeks of treatment and there were no relapses after treatment . The overall safety profile was similar to that known for telaprevir-based regimens . CONCLUSIONS Incorporating telaprevir into treatment of acute genotype 1 HCV in HIV-infected men halved the treatment duration and increased the SVR rate . Larger studies should be done to confirm these findings . Clinicians should be alert to detect acute HCV infection of HIV-infected men to take advantage of this effective therapy and decrease further transmission in this epidemic Methods for combining data from several studies exist and appear to be quite useful . None satisfactorily addresses the question of what studies should be combined . This issue is the most serious method ological limitation . Even studies with statistically significant interaction might still be combined if the effect were in the same direction . Thus , substantial scientific input is required as to what criteria must be met by each potential study . Much can be learned from combining or pooling data but it must be done cautiously . Pooling exercises do not replace well design ed prospect i ve clinical trials . Efforts for establishing basic design criteria to allow for multicentre and multicountry trials to be more easily combined might be useful . BACKGROUND Interferon-containing regimens for the treatment of hepatitis C virus ( HCV ) infection are associated with increased toxic effects in patients who also have cirrhosis . We evaluated the interferon-free combination of the protease inhibitor ABT-450 with ritonavir ( ABT-450/r ) , the NS5A inhibitor ombitasvir ( ABT-267 ) , the nonnucleoside polymerase inhibitor dasabuvir ( ABT-333 ) , and ribavirin in an open-label phase 3 trial involving previously untreated and previously treated adults with HCV genotype 1 infection and compensated cirrhosis . METHODS We r and omly assigned 380 patients with Child-Pugh class A cirrhosis to receive either 12 or 24 weeks of treatment with ABT-450/r-ombitasvir ( at a once-daily dose of 150 mg of ABT-450 , 100 mg of ritonavir , and 25 mg of ombitasvir ) , dasabuvir ( 250 mg twice daily ) , and ribavirin administered according to body weight . The primary efficacy end point was a sustained virologic response 12 weeks after the end of treatment . The rate of sustained virologic response in each group was compared with the estimated rate with a telaprevir-based regimen ( 47 % ; 95 % confidence interval [ CI ] , 41 to 54 ) . A noninferiority margin of 10.5 percentage points established 43 % as the noninferiority threshold ; the superiority threshold was 54 % . RESULTS A total of 191 of 208 patients who received 12 weeks of treatment had a sustained virologic response at post-treatment week 12 , for a rate of 91.8 % ( 97.5 % CI , 87.6 to 96.1 ) . A total of 165 of 172 patients who received 24 weeks of treatment had a sustained virologic response at post-treatment week 12 , for a rate of 95.9 % ( 97.5 % CI , 92.6 to 99.3 ) . These rates were superior to the historical control rate . The three most common adverse events were fatigue ( in 32.7 % of patients in the 12-week group and 46.5 % of patients in the 24-week group ) , headache ( in 27.9 % and 30.8 % , respectively ) , and nausea ( in 17.8 % and 20.3 % , respectively ) . The hemoglobin level was less than 10 g per deciliter in 7.2 % and 11.0 % of patients in the respective groups . Overall , 2.1 % of patients discontinued treatment owing to adverse events . CONCLUSIONS In this phase 3 trial of an oral , interferon-free regimen evaluated exclusively in patients with HCV genotype 1 infection and cirrhosis , multitargeted therapy with the use of three new antiviral agents and ribavirin result ed in high rates of sustained virologic response . Drug discontinuations due to adverse events were infrequent . ( Funded by AbbVie ; TURQUOISE-II Clinical Trials.gov number , NCT01704755 . ) To determine the rate of mother-to-child transmission of hepatitis C virus ( HCV ) and identify risk factors associated with HCV transmission we prospect ively studied 86 infants born to anti-HCV positive mothers . HCV infection was verified in all mothers before delivery and their HCV viral load was measured at or near delivery using reverse transcription polymerase reaction . For HCV genotyping the INNO-LiPA II probe assay was used . All mothers were tested for HIV infection . Possible risk factors for vertical transmission were recorded . The children were followed up for a minimum of 18 months for evidence of HCV infection , as determined by persistent HCV antibodies , or detection of HCV-RNA . Vertical transmission was restricted to infants born to viraemic mothers and the rate was 3.6 % ( 95 % CI 0.004–0.123 ) . The HIV-infected mothers and those using drugs intravenously were more likely to transmit HCV to their children . The infected children had the same genotype as their mothers . Although the HCV RNA titre was higher in mothers who transmitted the virus than in those who did not , the viral load had borderline significance ( p=0.08 ) . Viral transmission was not influenced by mother 's age , mode of delivery , genotype or type of feeding . Mother-to-child transmission of hepatitis C virus is uncommon and restricted to infants born to HCV viraemic mothers . Active drug use and HIV coinfection increase the risk for HCV vertical transmission Large data bases of consecutive patients followed for sufficiently long periods are needed to establish the rates , chronology , and hierarchy of complications of cirrhosis as well as the importance of other potential causes of liver disease . In accordance with this goal , a cohort of patients with compensated cirrhosis due to hepatitis C virus ( HCV ) was followed for 17 years . Two hundred and fourteen HCV RNA-seropositive patients with Child-Pugh class A cirrhosis who had no previous clinical decompensation were prospect ively recruited and followed up with periodic clinical and abdominal ultrasound examinations . During 114 months ( range 1 - 199 ) , hepatocellular carcinoma ( HCC ) developed in 68 ( 32 % ) , ascites in 50 ( 23 % ) , jaundice in 36 ( 17 % ) , upper gastrointestinal bleeding in 13 ( 6 % ) , and encephalopathy in 2 ( 1 % ) , with annual incidence rates of 3.9 % , 2.9 % , 2.0 % , 0.7 % , and 0.1 % , respectively . Clinical status remained unchanged in 154 ( 72 % ) and progressed to Child-Pugh class B in 45 ( 21 % ) and class C in 15 ( 7 % ) . HCC was the main cause of death ( 44 % ) and the first complication to develop in 58 ( 27 % ) patients , followed by ascites in 29 ( 14 % ) , jaundice in 20 ( 9 % ) , and upper gastrointestinal bleeding in 3 ( 1 % ) . The annual mortality rate was 4.0 % per year and was higher in patients with other potential causes of liver disease than in those without them ( 5.7 % vs. 3.6 % ; P = .04 ) . In conclusion , hepatitis C-related cirrhosis is a slowly progressive disease that may be accelerated by other potential causes of liver disease . HCC was the first complication to develop and the dominant cause for increased mortality To assess whether interferon-alpha might prevent non-A , non-B hepatitis from becoming chronic , 45 consecutive patients with transfusion-associated hepatitis were enrolled in a r and omized clinical trial . Thirty-eight patients had hepatitis C virus infection , and 7 had non-A , non-B , non-C hepatitis . Twenty-six patients ( 22 with HCV ) were given 3 MU of recombinant interferon-alpha 2b three times a week for 12 wk , whereas 19 ( 16 with HCV ) were not . Biochemical and virological parameters were monitored at regular intervals during an 18-mo follow-up . At the end of the 3-mo therapy , 16 ( 73 % ) patients with hepatitis C had normal serum ALT activity , compared with 7 ( 44 % ) who were not treated ( NS ) . Fifty-three percent of the treated patients and 
    Output:
    
Very low quality evidence suggests that interferon-alpha may decrease the incidence of  chronic HCV infection  as measured by sustained virological response .
However , the clinical impact such as improvement in health-related quality of life , reduction in cirrhosis , decompensated liver disease , and liver transplantation has not been reported .
It is also not clear whether this finding is applicable in the current clinical setting dominated by the use of pegylated interferons and direct-acting antivirals , although we found no evidence to support that pegylated interferons or ribavirin or both are effective in people with acute HCV infection .
We could find no r and omised trials comparing direct-acting antivirals with placebo or other interventions for acute HCV infection .