Combination therapy with interferon and ribavirin in the treatment of chronic hepatitis C infection

OBJECTIVE: To review and critique the medical literature regarding the combination of interferon and ribavirin in the initial treatment of chronic hepatitis C virus (HCV) infection. DATA SOURCES: A MEDLINE search (January 1966-June 1999) was conducted to identify human clinical trials regarding the combination of interferon and ribavirin therapy for the initial treatment of chronic HCV. Bibliographies were reviewed for relevant literature. STUDY SELECTION: Clinical trials of combination interferon and ribavirin for the treatment of chronic HCV in interferon-na?ve adults were reviewed. DATA SYNTHESIS: The combination of ribavirin and interferon in the treatment of chronic HCV has been beneficial in patients who are interferon-na?ve. Patients with predictors of poor response, such as baseline cirrhosis, male gender, age >40 years, high baseline viral loads (>2 x 10(6) copies/mL), and genotype 1 respond better to combination treatment when compared with those who receive interferon monotherapy. Patients with genotype 1 and/or high viral loads may benefit most from 48 weeks of combination therapy; however, adverse effects are of greater concern in these patients. Monitoring can limit these complications. CONCLUSIONS: Combination therapy is effective in the treatment of interferon-naive patients with chronic HCV infection. Patients should be evaluated for duration of treatment with combination therapy by determination of predictors of response. Further trials are needed to more closely evaluate the duration of treatment and to determine the best patient population to receive combination therapy.     

Combined interferon and ribavirin therapy for chronic hepatitis C in Taiwan

Chronic hepatitis C virus (HCV) infection, including its sequelae, is an important healthcare problem in Taiwan. The seroprevalence of HCV infection in first-time blood donors in Taiwan is 1.2% and an estimated 2-5% in the general population, with a great geographic variation. Genotype 1b is the most prevalent HCV genotype in Taiwan, with a prevalence rate of 50-70%. An increasing incidence of hepatocellular carcinoma (HCC) is mainly attributed to HCV infection, while the declining role of HBV is observed in Taiwan. The seroprevalence of hepatitis B surface antigen among patients with HCC was 90% three decades ago, while recently, chronic HCV infection accounts for more than 30% of HCC patients in the National Taiwan University Hospital. With the advent of a combined conventional interferon (IFN)-alpha and ribavirin therapy, to which Taiwan has contributed in the early study phase, the sustained virological response rate has been greatly improved compared with IFN monotherapy. The sustained virological response rate in Taiwanese patients treated with the combination therapy for 6 months has reached up to 50-60%, which is higher than that reported in patients from the Western countries receiving a 12-month regimen. It is necessary to search for the underlying mechanisms for the better treatment outcome with IFN plus ribavirin combination therapy in Taiwanese patients. Whether long-term effects of IFN plus ribavirin therapy can reduce the incidence of HCC needs to be established.     

Long-term outcome after interferon therapy in elderly patients with chronic hepatitis C

OBJECTIVE: The purpose of this study was to elucidate the long-term outcome after interferon (IFN) therapy in chronic hepatitis C elderly patients. METHODS: We studied the incidence of hepatocellular carcinoma (HCC) and survival probability after the initiation of IFN therapy in 500 Japanese chronic hepatitis C patients >60 years. The mean age of initiation of IFN was 63 years and the mean follow-up period was 7.4 years. Cox proportional hazard regression analysis was used to evaluate the long-term outcome after initiation of IFN therapy. Sustained virological response (SVR) was defined as negative HCV-RNA by RT-nested PCR 6 months after the completion of long-term IFN therapy. Non-response (NR) was applied to patients who did not show SVR. Hepatic fibrosis was defined as the fibrosis score (score 0-4) according to Knodell et al. RESULTS: 140 patients (28%) had an SVR and 360 patients (72%) had an NR. 71 of 500 patients developed HCC during follow-up. The cumulative incidence of HCC was 9.6% at the 5th year, 17.4% at the 10th year, and 31.3% at the 15th year. HCC developed with significance when: (1) HCV was not cleared after IFN therapy (p < 0.0001), (2) sex was male (p < 0.0001), and (3) staging of liver fibrosis was >2 (p = 0.008). 53 of the patients died. The cumulative survival probability was 95.7% at the 5th year, 86.4% at the 10th year, and 78% at the 15th year. Patients achieved a long survival with significance when: (1) staging of liver fibrosis was 1 (p < 0.0001), (2) HCV was cleared after IFN therapy (p = 0.034), and (3) sex was female (p = 0.015). CONCLUSION: Chronic hepatitis C patients with clearance of HCV after IFN therapy had a significantly reduced risk of HCC appearance and achieved prolonged survival even if they are > or =60 years.     

Significance of serum ribavirin concentration in combination therapy of interferon and ribavirin for chronic hepatitis C

OBJECTIVE: The purpose of this clinical retrospective cohort study was to determine the most suitable ribavirin concentration on combination therapy of interferon (IFN)-ribavirin. METHODS: Entry criteria were serum HCV-RNA level >/=100 KIU/ml, HCV-genotype 1b, chronic hepatitis, and initial combination treatment of IFN-alpha-2b (6 million units daily for 2 weeks and then 3 times weekly for 6 weeks) and ribavirin (600-800 mg/day) for 8 weeks without stopping or decreasing the dosage of IFN and/or ribavirin. Sixty-eight consecutive patients who satisfied the above criteria were given maintenance therapy for another 16 weeks. RESULTS: A sustained virological response (SVR) rate of 25.0% (17/68) was seen in all subjects. The SVR rate was 44.0% (11/25) in the high ribavirin group with a serum ribavirin concentration of >/=3,000 ng/ml at 8 weeks after initiation of combination therapy. SVR was significantly dependent at a serum ribavirin level of >/=3,000 ng/ml (p = 0.005). The incidence of discontinuations and dose modifications for combination therapy in patients having a serum ribavirin concentration of >/=3,500 ng/ml 8 weeks after initiation of therapy was 57.1% (4/7). This value was statistically higher than that in patents with <3,500 ng/ml (p = 0.033). CONCLUSION: Our results showed that the most suitable serum ribavirin concentrations are from 3,000 to 3,500 ng/ml 8 weeks after initiation of combination therapy.     

Very early viral kinetics on interferon treatment in chronic hepatitis C virus genotype 4 infection

BACKGROUND: Interferon (IFN)-resistant hepatitis C virus strains limit efficacy of antiviral combination therapy in patients infected with genotypes 1 and 4. A single test dose of IFN was useful to identify non-responders to IFN-alpha2b/ribavirin (RBV) or likely non-responders to pegylated (PEG)-IFN-alpha2a/RBV therapy in genotype 1 patients. Our aim was to investigate this approach in genotype 4 patients. METHODS: Viral load was measured in 46 patients before and 24 h after 10 megaunits (MU) IFN-alpha2b, and before and during 2 weeks of daily 5 MU IFN-alpha2b administration. Thereafter, patients received 48 weeks combination therapy with either 180 microg PEG-IFN-alpha2a/week (n=33), 1.5 microg/kg PEG-IFN-alpha2b/week (n=7) or 5 MU IFN-alpha2b/2 days (n=6), along with 1-1.2g RBV/day. For prediction analysis the largest group (PEG-IFN-alpha2a) was evaluated only. RESULTS: Median 24 h log10 change after 10 MU IFN-alpha2b was 1.15 (range 0.08-2.48) and after 5 MU IFN-alpha2b was 0.81 (-0.12-2.22; P<0.0001). Log10 changes after 2 weeks on 5 MU IFN-alpha2b daily and 24 h after 10 MU were the best predictors of early virological response (defined by negativity of a standard qualitative PCR) to PEG-IFN-alpha2a/RBV combination therapy (area under curve [AUC]=0.97; P<0.001, receiver operating characteristics), 24 h log10 change after 10 MU was the best predictor of sustained virological response (SVR; AUC=0.91, P=0.001). CONCLUSION: As in genotype 1 patients, there is large variation in IFN responsiveness, including the presence of resistant strains, in genotype 4 patients. A 24 h log10 change after 10 MU IFN-alpha2b is an excellent predictor of SVR on PEG-IFNalpha2a/RBV combination therapy. This test may be useful to obtain homogeneous groups for clinical studies and could help in clinical decision making.     

Impact of ribavirin exposure on early virological response to hepatitis C therapy in HIV-infected patients with chronic hepatitis C

BACKGROUND: The use of pegylated interferon (PEG-IFN) plus ribavirin (RBV) is currently the recommended treatment for chronic hepatitis C virus (HCV) infection. Coinfection with HIV is a negative predictor of response, for reasons not well understood. METHODS: We examined the virological response at weeks 4 and 12 in 198 HCV/HIV-coinfected patients enrolled in a prospective trial in which PEG-IFN alpha 2a (180 microg per week) and RBV (1000-1200 mg daily) were provided. RESULTS: In an on-treatment analysis, 52.8% of patients achieved undetectable HCV-RNA (<600 IU/ml) at week 4, while 63% and 77.2% of patients had a decline of at least 2 and 1 log10, respectively. At week 12, 73.1% of patients reached undetectable HCV-RNA, and 83.5% and 89% achieved at least a 2- and 1-log10 drop, respectively. More than 85% of HCV genotypes 2/3 cleared HCV-RNA at week 4, a proportion significantly higher when compared with genotypes 1 (33.8%) and 4 (28.6%). Multivariate logistic regression analysis identified genotype 3 and RBV exposure (mg/kg of body weight) as independent predictors of virological response at week 12 of therapy. CONCLUSION: Early virological response rates to PEG-IFN plus RBV in HCV/HIV-coinfected patients seem to be similar to those reported for HCV-monoinfected subjects. The use of suboptimal doses of RBV in most earlier trials might account for the low response rates seen in coinfected patients. To our knowledge, this is the first report demonstrating that RBV exerts a significant independent effect on early virological response. Therefore, strategies aimed at optimizing doses and adherence to RBV might help to improve responses to HCV therapy in coinfected patients.     

Retreatment of patients with chronic hepatitis C not responding to interferon/ribavirin combination therapy with daily interferon plus ribavirin plus amantadine

There is currently no accepted therapeutic regimen for patients with chronic hepatitis C who failed to respond to standard combination treatment with interferon-alpha plus ribavirin. We investigated triple combination treatment with induction dosing of interferon-alpha plus ribavirin plus amantadine in these difficult-to-treat patients. Nonresponders (n = 67), breakthroughs (n = 16) and relapsers (n = 19) to previous interferon/ribavirin combination treatment of at least 6 months were included. For the first 16 weeks, patients received interferon-alpha2a 6 MU daily, ribavirin 800-1200 mg/d, and amantadine 200 mg/d. In cases of undetectable HCV RNA at week 12, treatment was continued with interferon-alpha2a 6 MU every other day and the same doses of ribavirin and amantadine until week 48. In cases of HCV RNA positivity at week 12, treatment was stopped. A total of 102 patients were enrolled (80%: genotype 1, 19%: cirrhosis). HCV RNA was negative in 35/102 patients (34%) at week 12 and in 27/ 102 patients (26%) at the end of treatment. Virological response was sustained in 15/102 patients (15%). On-treatment virological response was higher in previous relapsers/breakthroughs than in previous nonresponders (week 12: 49% vs. 27%, p < 0.05; week 48: 46% vs. 16%, p < 0.01) but no such difference was found for sustained virological response (20% vs. 12%, NS). In conclusion, triple combination treatment with daily interferon-alpha plus ribavirin plus amantadine for 3 months can induce virological response in a considerable number of nonresponders/relapsers to previous dual combination treatment, but the sustained virological response rate remains low.     

Using pegylated interferon and ribavirin to treat patients with chronic hepatitis C

Hepatitis C virus is the most common chronic blood-borne infection in the United States. The advent of new treatment regimens using pegylated interferons in combination with ribavirin has led to improved sustained viral response rates for some genotypes in large multicenter trials. Advances in the management of side effects and toxicities have expanded the pool of treatable patients. A recent National Institutes of Health consensus conference recommended that all patients who have bridging hepatic fibrosis and moderate inflammation together with detectable viremia should receive treatment with pegylated interferon and ribavirin. Unfortunately, these medications are very expensive and have significant side effects. Hematologic toxicities include anemia and leukopenia. These can be managed with close monitoring, use of growth factors, or dose reductions. Depression also can be caused or exacerbated by these medicines and may require treatment with a selective serotonin reuptake inhibitor, comanagement with psychiatry, or cessation of pegylated interferon and ribavirin treatment. Contraception is imperative because ribavirin is highly teratogenic. Influenza-like symptoms of fatigue, nausea, and mild fevers can be helped by quality patient education and support including frequent office visits. Data from randomized controlled trials demonstrating improvements in long-term survival as a result of treatment are not yet available, but it appears that patients who have no detectable virus six months after treatment have a good chance of remaining virus free for at least five years.     

The effect of zinc supplementation on the treatment of chronic hepatitis C patients with interferon and ribavirin

OBJECTIVES: To evaluate the effects of zinc supplementation on serum zinc and copper levels, and the severity of adverse reactions and virologic responses in chronic hepatitis C patients undergoing interferon (IFN)/ribavirin therapy. DESIGN AND METHODS: Forty subjects were randomly assigned to receive IFN-alpha-2a/ribavirin with or without zinc gluconate for 24 weeks, then a period of 6 months for follow-up. Twenty healthy controls were also enrolled in the study. Blood samples were collected at different time points during therapy and at 6 months after the completion of therapy and were analyzed for zinc and copper levels. The adverse reactions and the virologic responses were also examined accordingly. RESULTS: Serum zinc levels were significantly lower in chronic hepatitis C patients than in healthy controls and further depressed by IFN/ribavirin treatment. However, serum zinc levels in patients were remediable by zinc supplements. No apparent difference was seen in virologic responses between subjects with or without zinc supplements, but certain adverse side effects associated with the zinc therapy were significantly decreased. CONCLUSIONS: Zinc supplementation may be a complementary therapy in chronic hepatitis C patients to increase the tolerance to IFN-alpha-2a and ribavirin.     

Clinical efficiency of high-dose interferon therapy in patients with chronic NCV hepatitis

11 patients with confirmed chronic HCV-hepatitis were treated with high-dose interferon. 12 matched controls were treated conventionally. Higher response was registered in patients on the interferon treatment. Side effects were not related to the variant of interferon therapy in the studied population.     

Alpha interferon and ribavirin combination therapy of chronic hepatitis D

The success of alpha interferon (IFN-alpha) monotherapy for the treatment of chronic hepatitis D is very limited. In this study, the efficacy of IFN-alpha and ribavirin combination therapy for chronic hepatitis D was investigated. Nineteen patients (15 males; mean age +/- standard deviation, 36.8 +/- 12.8 years) with chronic hepatitis D who were treated with IFN-alpha2b (10 million U, three times/week, subcutaneously) and ribavirin (1,000 to 1,200 mg/day, orally) for 24 months were studied. All patients had compensated liver disease (15 were precirrhotic), elevated transaminase levels, and hepatitis D virus RNA positivity at baseline. Genotypic analyses revealed hepatitis D virus genotype I and hepatitis B virus genotype D. All patients completed the 24 months of treatment and at least 6 months (7 to 19 months) of a follow-up period. Biochemical responses were observed in eight patients (42.1%) at the end of treatment and in seven patients (36.8%) at the end of follow-up. Eight patients (42.1%) at the end of treatment and four patients (21%) at the end of follow-up had virological responses. In conclusion, combination treatment of IFN-alpha and ribavirin for chronic hepatitis D is not able to induce virological responses at a sufficient rate, despite its partial effectiveness in improving biochemical responses, and is not superior to IFN-alpha monotherapy.     

PKR gene expression and response to pegylated interferon plus ribavirin therapy in chronic hepatitis C

Pegylated interferon (PEG-IFN) alpha combined with ribavirin is the current standard treatment for hepatitis C, but around 50% of patients do not respond for reasons that are not fully understood. To explore the regulation of IFN-inducible protein kinase (PKR), we have measured PKR mRNA levels in peripheral blood mononuclear cells (PBMCs) and in liver biopsies from patients with chronic hepatitis C. PBMCs were also analysed after in vitro incubation with IFN and during antiviral therapy. Non-responders to PEG-IFN plus ribavirin had pre-treatment PKR mRNA levels in PBMCs (0.1+/-0.0074) and in liver (0.102+/-0.051) that were significantly higher than those of responders (PBMCs: 0.023+/-0.014, P=0.0005; liver: 0.034+/-0.020; P=0.0002). On the other hand, PKR mRNA levels in PBMCs were similar in non-responders and in responders after in vitro exposure to IFN (0.434+/-0.301 vs 0.403+/-0.222; P=NS) and during therapy (0.31+/-0.10 vs 0.30+/-0.12; P=NS). These results indicate that in hepatitis C, non-responsiveness to IFN-alpha is associated with pre-treatment up-regulation of the PKR gene, evidence that the infecting hepatitis C virus is able to stimulate endogenous IFN production, being resistant to its antiviral effect. On the other hand, the PKR gene response to exogenous IFN was similar in responders and non-responders, at least in PBMCs, suggesting that variations in its activation are not major determinants of the outcome of antiviral treatment.     

Two-year interferon therapy with or without ribavirin in chronic delta hepatitis

The only beneficial agent for the treatment of chronic delta hepatitis (CDH) is interferon (IFN). However, there is no consensus on the best dosage or duration of IFN therapy. As ribavirin (RBV) increases the sustained response when added to IFN in chronic hepatitis C, probably because of its immunomodulatory effect, we aimed to investigate the efficacy of 2-year IFN treatment and whether RBV had any additive effect to IFN in CDH. METHODS: Patients (n = 31) with CDH were randomized with a 1:2 ratio as 10 patients (3 females/7 males, age 39 +/- 9) receiving IFN monotherapy (9 MU IFN-alpha2a three times weekly) and 21 patients (8 females/13 males, age 38 +/- 11) receiving IFN plus RBV for 2 years (IFN at the same dosage and RBV at 1000-1200 mg/day). Alanine transferase normalization and hepatitis delta virus (HDV) RNA negativity at the end of treatment and at the end of the follow-up period (at least 6 months following 2-year treatment) were primary endpoints of the study. In addition, virological response and biochemical response were determined separately. RESULTS: Eight of 31 patients (25%) had cirrhosis in liver biopsies. Six patients from the IFN monotherapy group and 12 patients from the combination group had biochemical response. Five patients from the IFN monotherapy group and 11 patients from the combination group had virological response at the end of therapy. Two patients from the IFN group and five patients from the combination group had sustained biochemical response at the end of the follow-up period. Hepatitis B virus (HBV) activations with HBV DNA positivity were observed in two patients (one from the IFN monotherapy group, one from the combination group). Two patients (20%) in the IFN group and five patients (23.5%) in IFN plus RBV group remained as virological responders at the end of the follow-up period (P > 0.05). None of the patients with liver cirrhosis were responsive at the end of the follow-up period. CONCLUSION: Almost 20% of the patients with CDH were responsive to 2-year IFN treatment at the end of the follow-up period and no additional effect of RBV was observed. Patients with advanced liver disease failed to respond to treatment.     

Vitiligo associated with pegylated interferon and ribavirin treatment of patients with chronic hepatitis C: A case report

The use of pegylated interferon (PEG-IFN) and ribavirin is considered standard therapy for patients with chronic hepatitis C. Many adverse effects of IFN appear to be of autoimmune origin. Vitiligo is a hypomelanotic disease, whose cause, despite many investigations, remains unknown, although some evidence points to an autoimmune pathogenesis. This report describes a case of vitiligo that occurred during the third month of treatment with PEG-IFN and ribavirin. The sustained virologic response was the result of a 52-week regimen; however, hypomelanotic cutaneous patches persisted. Autoimmune adverse effects of IFN therapy, which may include vitiligo, should be carefully monitored. The decision about whether to discontinue treatment should be discussed with the patient, who must be informed that the lesions may persist.