An escalating dose regime of recombinant interferon-alpha 2A in the treatment of chronic hepatitis C

Comparison among Different Types, Dosages and Duration of Interferon Therapy in Chronic Hepatitis C

In an attempt to determine the best therapeutic protocol for the treatment of chronic hepatitis C with interferon (IFN), we reported our experience comparing the efficacy of IFN at the usual dose and duration, i.e. 3 million units (MU) three times weekly for 6 months, with the immediate and long-term effects of different types, dosages and duration of IFN therapy. 300 patients with chronic hepatitis C were randomly assigned to five groups of 60 subjects each and treated as follows: group A - recombinant IFN alpha (rIFNalpha) 3MU three times weekly for 6 months; group B - rIFNalpha 6MU three times weekly for 6 months; group C - rIFNalpha 3MU 3 times weekly for 12 months; group D - lymphoblastoid IFN (L-IFN) 6MU three times weekly for 6 months; group E - L-IFN 3MU three times weekly for 12 months. The diagnosis of hepatitis was based on clinical, serological and histological data in all patients. A 'biochemical response' was defined as the normalisation of alanine aminotransferase (ALT) values, and a 'complete response' as the normalisation of ALT with disappearance of serum hepatitis C virus (HCV)-RNA. A 'sustained response' was defined as the persistence of ALT normalisation and undetectable viraemia 2 years after the end of treatment. The five groups were homogeneous. The incidence of dropouts was 8%, and IFN treatment was interrupted for adverse effects in 11% of the patients. In group A, 55% of the patients showed a 'biochemical response' and 31% of the subjects demonstrated a 'complete response'. In group B, a 'biochemical response' was observed in 61% and a 'complete response' in 36% of the cases. In group C, 77% of the subjects showed a 'biochemical response', with a 'complete response' seen in 40%. In group D, we observed a 'biochemical response' in 55% of the patients and a 'complete response' in 33%. In group E, 79% of the subjects had a 'biochemical response', and a 'complete response' was seen in 38%. At the end of the treatment-free follow-up the percentage of patients with a sustained response was 24% in group A, 28% in group B, 35% in group C, 27% in group D and 33% in group E. Therefore, a longer period of IFN treatment seems to provide higher percentages of sustained response than the usual 6-month duration, independently of the type of IFN. Moreover, the patients treated with a higher dosage (6MU 3 times weekly) for 6 months showed a slightly better sustained response rate compared with the usual dose. In conclusion, even if the differences among the response rates in the five groups were not statistically significant, we recommend a 12-month regimen, possibly using higher dosages at least in the first 4 to 6 months of treatment.

Monitoring response during a randomised controlled trial of escalating interferon dose for chronic hepatitis C infection: predictive value of quantitative and qualitative HCV RNA assays

BACKGROUND

In chronic hepatitis C infection, raising the interferon dose in initial non-responders may increase the generally poor sustained response rates. Monitoring virological response is essential in this kind of individual patient based approach. Quantitative HCV RNA assays are increasingly used for this purpose. However, their additional value as compared to strictly qualitative HCV RNA assays should be evaluated before they are implemented as a routine measurement, since these assays are more expensive and time consuming than qualitative assays.

OBJECTIVES

Goals of this study were (1) to test the hypothesis that increasing interferon dose in initial non-responders results in permanent viral clearance in more patients and (2) evaluation of the predictive value of quantitative versus qualitative HCV RNA assays before and during treatment.

STUDY DESIGN

63 patients were treated in a randomised controlled trial of escalating interferon dose. In the standard treatment group patients received 6 MU alpha-2a thrice weekly for 3 months followed by 3 MU thrice weekly for 3 months. In the experimental group interferon dose was escalated at 6 weeks to 9 MU if HCV RNA was still detectable at 4 weeks. Predictors of response were analyzed at various time points before and during treatment and the predictive value of quantitative HCV RNA measurements was compared to that of qualitative HCV RNA assays.

RESULTS

No significant difference in sustained response rate was found between the treatment groups at the end of follow-up. At baseline, the strongest independent predictor for a sustained response was a viral load level below 10(6) copies/ml and age younger than 40 years. During treatment a negative HCV RNA status at week 4 was the strongest predictor of a sustained response. Viral load levels during treatment did not independently predict a sustained response.

CONCLUSIONS

While on treatment, qualitative HCV RNA assays should be used to monitor response.

The Effect Of Long Term and High Dose Interferon Treatment In Chronic Hepatitis C

The results of 43 interferon treatments of 35 patients (23 male, 12 female) are reported. The duration of the treatment was 6-18 months, the dose of interferon was 3x3-5 MU weekly. Complete response (HCV RNA became negative) was found in 11, relapse was observed in 3 patients. Partial response (transaminase levels became normal, or less than twice normal value, but patients remained HCV RNA positive) occurred in 23 cases, relapse was obeserved in 16. The therapy had no effect in 9 cases. The higher dose and longer term interferon therapy resulted in a higher rate of response to the treatment and a reduction in the number of relapses.

A multicenter, randomized trial of daily high-dose interferon-alfa 2b for the treatment of chronic hepatitis c: pretreatment stratification by viral burden and genotype

OBJECTIVES

The aim of this study was to determine prospectively whether an intensive regimen of daily, high-dose interferon would improve the response rate for the treatment of chronic hepatitis C in patients with unfavorable virological characteristics.

METHODS

A total of 104 patients with chronic hepatitis C were randomized at eight centers to receive interferon alfa-2b at a dose of 5 million units (MU) daily or 3 MU t.i.w. for a period of 24 wk. Patients were prospectively randomized by low or high viral burden and stratified by genotype. HCV RNA was measured by quantitative polymerase chain reaction, and response rates were compared between the dosage regimens.

RESULTS

HCV RNA levels dropped more rapidly to lower levels in the group treated with 5 MU daily. In this group, the initial virological response (IR) at wk 12 and the end-of-treatment response (ETR) at wk 24 were double that of patients treated with standard interferon (66% vs 33% and 48% vs 24%, p < 0.01). Sustained response rates were low for both dose groups (14% vs 4%, p = 0.08). Genotype-related differences in initial response rates were present in the standard dose group (63% non-1 genotype vs 24% genotype 1; p = 0.005) but not in those treated with 5 MU daily (66% vs 67%, p = NS). Using multivariate analysis, only the interferon dose was associated with IR and ETR (p = 0.002).

CONCLUSIONS

Daily, high dose interferon rapidly dropped HCV RNA and increased initial and end-of-treatment response rates when compared to t.i.w. regimens. This effect, independent of viral burden and genotype, suggests that patients with unfavorable viral characteristics might benefit from an intensive regimen that promotes rapid viral clearance. These data support further study of the use of high-dose induction regimens. However, improvements in sustained response rates will require additional therapeutic maneuvers such as prolonged therapy or the adjunctive use of ribavirin.

Treatment of chronic hepatitis C virus infection

OBJECTIVE

To review the literature on the treatment of chronic hepatitis C virus (HCV) infection.

DATA SOURCES

MEDLINE search (1986-December 1999) using key words such as HCV, hepatitis, non-A and non-B hepatitis, as well as terms regarding treatment during that time period.

DATA SYNTHESIS

HCV infection was initially treated with interferon monotherapy, but only a minority of patients responded to long-term therapy. A higher rate of response in both interferon-naïve patients and interferon-relapsers has been achieved by using the combination of interferon and ribavarin. Other treatment regimens including high-dose interferon protocols, ursodeoxycholic acid, amantadine, and nonsteroidal antiinflammatory drugs have been less promising. Many alternative therapies are being investigated.

CONCLUSIONS

HCV infection is a major public health problem. It is now possible to achieve a cure in nearly 50% of the patients with this infection. Many additional therapies are being evaluated in order to achieve a higher cure rate.

Early addition of ribavirin to interferon in chronic hepatitis C not responsive to interferon monotherapy

BACKGROUND/AIM

Persistence of HCV-RNA in serum early in treatment is a strong predictor of failure of alpha-interferon therapy for chronic hepatitis C. Therefore, we compared the efficacy of ribavirin addition to alpha-interferon with a doubling of the dosage of alpha-interferon in case of lack of early virological response to alpha-interferon therapy.

METHODS

Sixty patients were administered interferon alpha2b at the dosage of 3 million units 3 times a week. After the first 4 weeks of therapy, serum HCV-RNA was evaluated. The patients with negative HCV-RNA test received the same treatment for a further 11 months, while those with detectable HCV-RNA were randomized to receive either the same dosage of alpha-interferon plus ribavirin (1000 mg/day) or double dosage of alpha-interferon (6 million units tiw) for 11 months. We considered sustained response to be the maintenance of normal alanine aminotransferase and negativity at HCV-RNA testing until the end of a 6-month post-treatment follow-up.

RESULTS

After the first 4 weeks of treatment, 12 (20%) patients showed virological response and 48 patients (80%) remained positive on HCV-RNA testing. Sustained response was observed in 5/12 (42%) patients with early virological response, in 10/24 (42%) patients without early virological response who were administered ribavirin and alpha-interferon, and in only 1/24 (4%) patients who were administered the double dosage of alpha-interferon (p=0.006).

CONCLUSIONS

This study shows the efficacy of the addition of ribavirin to alpha-interferon and the lack of efficacy of doubling the dosage of alpha-interferon in patients without clearance of hepatitis C virus early on in treatment.

Hepatitis C

In the latter half of the 20th century, HCV emerged as the most common cause of chronic liver disease, and will likely remain so. Since its initial discovery in 1989, rapid progress has been made in our understanding of the virology, epidemiology, natural history, diagnosis, and treatment of HCV. Over the next few decades, as further advancements are made, superior treatment options will become available.

New drugs for hepatitis C virus (HCV)

Lack of efficacy and significant side effects have severely limited the use of interferon-alpha (IFN-alpha) as the standard therapy for non-A non-B hepatitis (NANBH) caused by hepatitis C virus (HCV) and alternative, improved therapies are urgently sought. Attempts have been made to improve the potency and tolerability of IFN-alpha by adjusting dosing regimens, methods of delivery and length of treatment. Furthermore, a number of different agents have been used in combination wit IFN-alpha and, from these studies, therapeutic options have been galvanized by the synergistic effects of IFN-alpha and ribavirin. Nevertheless, the majority of patients with HCV still do not sustain lasting therapeutic benefit from this combination and continuing research is required to identify new therapeutic candidates that will have more potent antiviral activity and less severe side effects. This review focuses on the progress that has been made in this area and the prospects for new effective therapies in the near future.

Long-term administration of interferon-alpha in non-responder patients with chronic hepatitis C: follow-up of liver fibrosis over 5 years

In chronic hepatitis C, previous data have shown that short-term treatment with interferon-alpha (IFN-alpha) can reduce collagen deposition in the liver independently of the viral response. The aim of this work was to determine, in non-responder patients, the long-term effect of IFN-alpha on liver fibrosis according to the total administered dose and the fibrotic stage. Fibrosis was investigated on liver biopsies from 24 non-responder patients with chronic hepatitis C retreated with successive courses of IFN-alpha. The degree of liver fibrosis was assessed on three successive biopsies, performed before IFN-alpha treatment and 1 and 5 years later, in 13 and 11 patients, respectively, treated for less (mean: 7.5 months, 313 MU) and more (mean: 21.8 months, 791 MU) than 1 year. For each biopsy, fibrosis was assessed using a histological semiquantitative fibrosis scoring system and by morphometry after picrosirius red staining. Regardless of the dose and duration of IFN-alpha therapy, a slight decrease of fibrosis was observed in patients 5 years after starting treatment. In cirrhotic patients, a short treatment induced an improvement followed by a relapse of fibrosis in 57%, and only 43% of patients showed constant collagen regression over the 5 years of follow-up. On the contrary, after prolonged therapy, a progressive and significant decrease occurred throughout the follow-up period in all patients (P = 0.045). Long-term treatment with IFN-alpha is therefore associated with regression of liver fibrosis, particularly in cirrhotic patients. These promising results need to be confirmed in a larger series of patients.

Liver biopsy is a useful predictor of response to interferon therapy in chronic hepatitis C

AIM

To evaluate the usefulness of easily assessable morphological parameters in liver biopsies in order to predict efficacy of interferon-alpha (IFN) treatment in patients with chronic hepatitis C.

METHODS AND RESULTS

Inflammatory activity and fibrosis (according to Scheuer), and the hepatic iron content (according to Rowe and DiBisceglie) were assessed in pre-treatment liver biopsies of 73 de novo patients with chronic hepatitis C. Furthermore the presence of fat, lymphoid aggregates, and bile duct lesions was evaluated. With respect to IFN therapy patients were classified as responders alanine aminotransferase (ALT) normal and negative hepatitis C virus (HCV) RNA in serum at the end of treatment, n = 33) or non-responders (n = 40). Non-responders had more advanced fibrosis (P = 0.0001) and more extensive iron storage (P = 0.0008) than responders. In contrast absence of stainable iron was frequently (46%) associated with sustained response. Absence of fat droplets in hepatocytes was associated with response (P = 0.0001). Stepwise logistic regression analysis indicated that the stage of fibrosis, the hepatic iron grade, and the presence or absence of fat were independent predictors of response.

CONCLUSIONS

Liver biopsy provides useful information for selection of patients with hepatitis C for IFN therapy.

Incidence and severity of acute allograft rejection in liver transplant recipients treated with alfa interferon

Interferon alfa-2b (IFN-alpha) therapy has been shown to be effective in the treatment of viral hepatitis B (HBV) or viral hepatitis C (HCV) in patients who did not undergo transplantation. However, in allograft recipients, treatment with IFN-alpha often leads to allograft rejection. The aim of the present study was to determine if IFN-alpha therapy increases the incidence or severity of acute rejection in human liver allograft recipients. One hundred five orthotopic liver transplant (OLT) recipients with HBV (n = 32), HCV (n = 58), or Non A Non B Non C (n = 15) viral infections were treated with a 6-month course of IFN-alpha, 5 million U subcutaneously three times a week, which began 2 to 97 months after transplantation. The mean hepatitis activity index (HAI) at the beginning of the therapy was 10.1 +/- 3.0. The baseline immunosuppression was achieved by tacrolimus in 77 patients and by cyclosporine A (CyA) in 28 patients. Contemporaneous controls consisted of 132 OLT patients (100 who received tacrolimus and 32 who received CyA) who did not receive IFN-alpha. A retrospective analysis was performed on this group of patients. The incidence of rejection and the baseline immunosuppression were compared. All biopsies were reviewed without knowledge of clinical data and scored for HAI and for rejection activity index (RAI). The biochemical response to IFN-alpha was also examined. The mean baseline maintenance dose of prednisone was greater by 2 mg daily in patients who received IFN-alpha with tacrolimus compared with control patients who did not receive IFN-alpha with tacrolimus (IFN-alpha 5. 3 +/- 5.2 mg daily v controls 3.3 +/- 4.9 mg daily; P </= .05). Similarly, the mean maintenance dose of prednisone was greater by 2.5 mg daily in patients who received IFN-alpha compared with controls who received CyA-based immunosuppression (IFN-alpha 9.8 +/- 3.1 mg daily v controls 7.3 +/- 3.3 mg daily; P = .01). Acute rejection episodes were detected in 10.5% (n = 11) of IFN-alpha-treated patients compared with 8.8% of controls for the similar time period from OLT and period of exposure to risk of rejection. Mean RAI was 2.0 +/- 2.4 for the IFN-alpha-treated group and 2.1 +/- 1.7 for controls. Rejection episodes with IFN-alpha treatment were mild and responded to steroid therapy. In OLT recipients, the risk of acute rejection was not increased by the introduction of IFN-alpha. However, in this study, patients were exposed to greater levels of immunosuppression.

Quantification of the initial decline of serum hepatitis C virus RNA and response to interferon alfa

Although several virus- and host-related predictive factors for the response to interferon alfa (IFN-alpha) have been defined in patients with chronic hepatitis C, no pretreatment parameter can definitely predict the response to antiviral treatment. Assessment of the initial response by quantification of serum hepatitis C virus RNA before and 4 weeks after initiation of therapy may be a clinically applicable and reliable parameter to predict long-term response. Therefore, the aims of the present study were to test the predictive value of a decline in HCV RNA of at least 3 log in the first 4 weeks of treatment (deltaHCV RNA) in patients treated with 3 x 10(6) units of recombinant IFN-alpha2a (rIFN-alpha2a) three times per week subcutaneously and to compare deltaHCV RNA with other established predictive factors, such as HCV genotype and pretreatment viremia. Serum HCV RNA was measured by a validated quantitative reverse transcription-polymerase chain reaction (RT-PCR). Geno/subtyping of HCV was performed by direct sequencing of the nonstructural (NS) 5B region of PCR-amplified isolates and subsequent phylogenetic analysis. Stable HCV RNA levels (deltaHCV RNA < or = 1 log) within the first 4 weeks of IFN-alpha treatment were present in 42 of 70 patients. A decline in HCV RNA levels between 1 to 3 log and more than 3 log was observed in 9 (13%) and 19 patients (27%), respectively. In 21 of 70 patients (30%), HCV RNA was not detectable at the end of 12 months' treatment. Three of 26 patients (11%) with a pretreatment viremia of < or = 10(6) copies/mL (all HCV subtype 3a) and 6 of 44 patients (14%) with a pretreatment viremia of > 10(6) copies/mL (HCV subtypes 1b, 2a, 2c, 3a [two patients], and 4) achieved a virological sustained response to interferon-alpha2a treatment. All patients with a virological sustained response had an initial deltaHCV RNA of more than 3 log. In a stepwise discriminant-function analysis, the initial deltaHCV RNA was confirmed as the strongest predictor of virological sustained response (P < .0001). In conclusion, the data of the present study suggest that IFN-alpha treatment can be terminated after 4 weeks in patients with a decrease in HCV RNA levels of less than 3 log, when apparent HCV eradication is considered the therapeutic target. The predictive value of deltaHCV RNA clearly exceeds the significance of HCV genotype and pretreatment viremia as predictors of successful IFN-alpha treatment.

Alpha interferon therapy in Danish haemophiliac patients with chronic hepatitis C: results of a randomized controlled open label study comparing two different maintenance regimens following standard interferon-alpha-2b treatment

Following a survey among all Danish haemophiliac patients 49 HIV-negative patients with chronic hepatitis C were offered enrollment in a randomized controlled open label study comparing two different maintenance regimens following standard interferon-alpha-2b treatment. Dose modifications and treatment discontinuation were based upon changes in transaminase levels. Forty-seven patients enrolled received 3 MU of alpha interferon thrice weekly (TIW) for 3 months. Twenty-six nonresponders had their dose increased to 6 MU TIW for an additional 3 months, while 21 responding patients continued on 3 MU TIW. At 6 months, 25 patients with a complete or a partial biochemical response were randomly allocated to either a fixed dose regimen (13 patients) (3 or 6 MU thrice weekly) or an individualized dose regimen (12 patients) tapering interferon dose from 3 or 6 MU by one-third every 2 months if transaminases were persistently normal. The remaining 22 biochemical nonresponders were followed for an additional 6 months without further treatment. After 12 months of treatment, 18 patients (38%) had a virological response, irrespective of regimen, and seven patients (16%) had a sustained virological and biochemical response after 6 months of follow up. Overall, the individualized treatment regimen did not seem to offer any advantage over the fixed dose regimen. The response to alpha interferon treatment in Danish haemophiliac patients with chronic hepatitis C immediately after treatment is comparable to that obtained in previous studies among nonhaemophiliacs. However, a sustained virological and biochemical response was seen in only 16% of treatment patients.

A pilot study on the efficacy of escalating dosage of alpha-interferon for chronic hepatitis C in HIV-infected patients. The Hepatitis/HIV Spanish Study Group

Chronic liver disease caused by hepatitis C virus (HCV) seems to present a more accelerated course in HIV-infected patients, leading to cirrhosis and liver failure in a shorter period of time than in HIV-negative individuals. As efforts to increase life expectancy in HIV-infected people progress, substantial morbidity and mortality from HCV infection is likely to arise amongst subjects infected parenterally, such as injecting drug users, haemophiliacs and transfusion recipients. Preliminary results have suggested that alpha-interferon (IFN) treatment allows higher rates of response in HIV-infected patients with higher CD4+ lymphocyte counts, suggesting a primary dependence of IFN on a preserved immune system in order to act appropriately. In an open, multicentre, prospective trial we analysed whether the use of larger doses of IFN, through an escalating schedule, might overcome the limits imposed by immune dysfunction. An interim analysis performed in 29 patients concluded that escalating the dosage did not improve the rate of response to IFN. In fact, only one (8.3%) out of 12 patients without response after 3 months of being on IFN therapy achieved response after the dosage was increased from 5 MU to 8 MU s.c. three times a week. Moreover, he relapsed 3 months after completion of treatment for 1 year.

Fixed versus titrated interferon-alpha 2B in chronic hepatitis C. A randomized controlled multicenter trial. The Swiss Association for the Study of the Liver

BACKGROUND/AIM

Interferon has become the mainstay of treatment of chronic hepatitis C; however, duration of treatment and dose remain unresolved questions. The present study aimed to compare standard dose interferon with a titrated dose regimen carried out for 1 year.

METHODS

This was a randomized, controlled multicenter trial. Patients with chronic hepatitis C were randomly allocated to a control group (n = 30), to a fixed dose group (n = 31) where interferon-alpha 2b 3 MU thrice weekly was given for 1 year or a titrated group (n = 34) where interferon was titrated starting at 5 MU thrice weekly to the lowest dose keeping the patient in remission as assessed by a normal ALT value. Liver biopsies were obtained before and at the end of treatment; in addition, galactose elimination capacity was measured as a measure of cytosolic function.

RESULTS

In the control, fixed and titrated groups a complete response was achieved in 2/29, 10/28 and 15/31, respectively (p < 0.001 in favor of treatment, p = n.s. for the two treatments). The corresponding figure for sustained response was 1/29, 5/28 and 6/ 31 (p = n.s). In the titrated group, a complete (sustained) response was achieved with 5 MU in 2 (2), with 4 MU in 1 (0), with 3 MU in 4 (0), with 2 MU in 3 (0) and with 1 MU in 5 (4). Liver biopsy score and galactose elimination capacity improved significantly in responders but not in treatment failures.

CONCLUSIONS

Both fixed and titrated dosing of interferon given for 1 year induced virus clearance in only a minority of treated patients. However, in a small number of patients, a complete and sustained response can be achieved with low doses of interferon. Dose titration could be an interesting approach to decreasing the cost and side effects in the treatment of chronic hepatitis C.

Transfusion-associated chronic hepatitis C: alpha-n1 interferon for 6 vs. 12 months

AIMS

To compare the long-term effects of brief and prolonged therapy with alpha-n1 interferon for transfusion-associated chronic hepatitis C.

METHODS

One hundred and sixteen subjects (male/female 48/68, mean age 46.9 years) were studied. Sixty patients were randomised to brief treatment (group 1: interferon 5 Mu/msq. t.i.w. for 2 months, then 3 Mu/msq. t.i.w. for 4 months), and 56 to prolonged treatment (group 2: interferon 5 Mu/msq. t.i.w. for 2 months, then 3 Mu/msq. t.i.w. for 10 months). All were followed for 12 months after stopping interferon.

RESULTS

The early response rate was 47.4% (Group 1 [45%], Group 2[50%]. No "breakthrough" reactivations were observed. The early response rate was 19% in patients with and 63% in patients without cirrhosis. Twenty-three (19.8%) subjects stopped therapy. Among 54 evaluable early responders, 21 had a sustained response. The rate of sustained response was comparable in group 1 (18.3%) and group 2 (18.2%). All sustained response subjects and some non-responders were HCV-RNA negative at the end of follow-up. Histological improvement was seen only after sustained response. Cirrhosis developed in 20% of non-responders. Overall, interferon induced a long-lasting remission of chronic hepatitis C in about one of every five patients.

CONCLUSIONS

In a population predominantly infected by hepatitis C virus type 1, 12 months of therapy with high doses of interferon does not confer any additional benefit on the early response or sustained response rates as compared to a 6-month course.

Low dose alpha interferon therapy can be effective in chronic active hepatitis C. Results of a multicentre, randomised trial

BACKGROUND

There is some controversy concerning the efficacy of low dose alpha interferon therapy in chronic hepatitis C.

AIMS

To evaluate the effectiveness of treatment with low doses of alpha interferon in chronic hepatitis C.

PATIENTS

One hundred and forty one patients with anti-HCV positive chronic active hepatitis C from six hospitals were enrolled in the study.

METHODS

Patients were randomised to treatment with 5 MU (group A) or 1.5 MU (group B) injections. The dose was reduced in responders from group A or increased in non-responders from group B to maintain treatment with the minimal effective dose. Patients were treated for 48 weeks and followed up for 24 additional weeks with no treatment. Normalisation of alanine aminotransferase (ALT) was used to evaluate response.

RESULTS

A sustained response was seen in eight patients from group A (12%) and in 15 (21%) from group B. This difference was not statistically significant. Increasing the dose of interferon led to sustained response in only five of 58 patients (9%) from group B who did not respond to 1.5 MU injections. In contrast, 15 of 21 patients (71%) in whom ALT remained normal with 1.5 MU injections developed a sustained response. By multivariate analysis sustained response seemed associated with young age and was more frequent in patients with genotype 3 HCV infection. Sustained response was preceded by a rapid normalisation of ALT and was inversely related to the amount of alpha interferon necessary to maintain ALT at low values during treatment.

CONCLUSIONS

Some patients with chronic hepatitis C are very sensitive to alpha interferon and can be successfully treated with low doses. Treatment with higher doses may be effective in a minority of patients who do not respond to low doses.

Interferon-alpha-2a. A review of its pharmacological properties and therapeutic use in the management of viral hepatitis

Interferon-alpha-2a is a recombinant interferon with antiviral, antitumour and immunomodulatory properties. Clinical studies have demonstrated that the drug offers therapeutic benefit in patients with some forms of chronic viral hepatitis. Remission, as measured by clearance of viral DNA and hepatitis B 'e' antigen (HBeAg), and normalisation of serum alanine aminotransferase levels, is observed in approximately 30 to 45% of patients with chronic hepatitis B receiving interferon-alpha-2a (2.5 to 18MU administered 3 times/week); about 5 to 15% of untreated controls remit spontaneously every year. Complete recovery [with loss of hepatitis B surface antigen (HBsAg)] is usually noted in < 20% of treated individuals. Similar response rates have been reported in the relatively small number of children evaluated to date. Although numerous studies have shown that interferon-alpha-2a (at various dosages) induces biochemical amelioration of chronic hepatitis C in approximately 50 to 75% of patients, relapse is common. Thus, long term remission may only be observed in about 15 to 30% of treated patients. On the other hand, this disorder remits spontaneously in only a few patients. The role of interferon-alpha-2a in the treatment of chronic hepatitis D remains unclear. Although preliminary data suggest it may be beneficial, cessation of therapy is generally followed by relapse. As with other types of interferons, most patients receiving interferon-alpha-2a experience an 'influenza-like' syndrome, which tends to diminish with continuing therapy. Other effects such as fatigue, lethargy, anorexia and weight loss are usually dose-limiting. Serum neutralising antibodies develop in approximately 10 to 20% of treated patients. Thus, although response rates are less than optimal, interferon-alpha-2a is a drug of first choice amongst the limited therapeutic options available for the management of well-compensated chronic viral hepatitis B or C.

Lack of benefit of escalating dosage of interferon alfa in patients with chronic hepatitis C

BACKGROUND & AIMS

In patients with chronic hepatitis C treated with interferon alfa, sustained normalization of alanine aminotransferase was observed in about 20%, and no predictive factor of response could be clearly identified. The aims of this study were to assess the efficacy of an escalating dose of interferon and to determine the predictive factors of response.

METHODS

Seventy-five patients were randomly assigned to two groups. Twenty-five patients received a dosage of 3 million units of recombinant interferon alfa-2b three times weekly for 24 weeks, and 50 patients received a dose that was increased to 5 million units at 8 weeks in nonresponders and to 10 million units 8 weeks later in persistent nonresponders. Multivariate analysis was performed to determine the features associated with response.

RESULTS

A sustained response was observed in 17% of the patients with constant dosage and in 19% of patients with an escalating dosage. Low pretreatment serum hepatitis C virus RNA levels and hepatitis C virus genotype were found to be independent predictive factors of sustained response.

CONCLUSIONS

In patients with chronic hepatitis C, an escalating dosage of interferon did not improve the overall rate of response. Low pretreatment serum hepatitis C virus RNA levels and genotype other than 1b were the only predictive factors of sustained response.

Predictive factors for beneficial response to interferon-alfa therapy in chronic hepatitis C

OBJECTIVES

Interferon is the only established treatment for chronic hepatitis C but the host-dependent or virus-related factors affecting the response rate to interferon therapy are not yet clear. The purpose of this study was to investigate the factors predictive of response to interferon-alfa therapy in chronic hepatitis C.

METHODS

Twenty-five consecutive patients with chronic hepatitis C were randomized to three regimens of interferon-alfa: group A (n = 7, 3 MU every day for 3 months), group B (n = 8, 3 MU every other day for 3 months) and group C (n = 10, 3 MU every other day for 6 months). We quantified serum HC RNA levels by competitive reverse transcription-polymerase chain reaction (RT-PCR) and performed HCV genotyping using type-specific primers deduced form the NS5 region of the HCV genome. We also attempted to identify which demographic, biochemical and histologic factors in addition to virus-related factors would significantly predict beneficial response to interferon by multivariate analysis.

RESULTS

Sustained responders were 8 (36.4%), nonsustained responders were 2 (9.1%) and nonresponders were 12 (54.5%) of 22 patients who had received complete therapy. The initial HCV RNA level (logarithmic transformed copy numbers per ml of serum) in sustained responders (5.75 +/- 0.39) was significantly lower than that of nonsustained responders (6.80 +/- 0.71) and nonresponders (6.70 +/- 0.52) (p < 0.05). In multivariate multiple logistic regression analysis, the serum HCV RNA level before therapy was only the independent predictor of a sustained response to interferon-alfa therapy (p = 0.001).

CONCLUSIONS

Serum HCV RNA level before therapy was the most useful predictor of a sustained response to interferon-alfa therapy for chronic hepatitis C.

Hepatitis C virus RNA and long-term response to recombinant interferon-alpha 2b in patients with chronic hepatitis C

The effectiveness of recombinant interferon-alpha 2b (rIFN-alpha 2b) in eradicating hepatitis C virus (HCV) RNA from serum has not been completely assessed. We studied 39 patients with compensated chronic hepatitis C diagnosed by liver biopsy and positive HCV RNA measured by polymerase chain reaction (PCR). Group I consisted of 26 patients treated with 3 MU of rIFN-alpha 2b for 6 months; group II, 13 control patients observed for six months; and group III, 12 out of 13 patients from group II who subsequently received 5 MU of rIFN-alpha 2b for 6 months. In group I, 11 out of 23 (47.8%) patients who completed treatment had an immediate response and five (21.7%) had a sustained response to therapy six months after treatment. No response was observed in patients from group II. In group III, 7 out of 12 (58.3%) patients who completed treatment had an immediate response and none had a sustained response. Considering all patients who completed rIFN-alpha 2b treatment, HCV RNA remained positive at the end of therapy in three of five sustained responders (60%), six of 13 patients who relapsed (46.1%), and in all nonresponders (100%). HCV RNA was positive 6 months after therapy in four (80%), 13 (100%), and 17 (100%) patients respectively. All patients with a sustained response had normal aminotransferase levels 18 months after therapy. We conclude that in chronic hepatitis C rIFN-alpha 2b causes a significant immediate response but this is not sustained, only 2.8% of treated patients had a sustained loss of HCV RNA. Normal aminotransferase persist in the long term, despite persistence of HCV RNA.

Serum levels of soluble immune factors and pathogenesis of chronic hepatitis C, and their relation to therapeutic response to interferon-alpha

To test the role of immune reactivity in the pathogenesis of hepatitis C, serum soluble immune factors were measured in a cohort of 57 patients with chronic hepatitis C, and in 20 healthy subjects. Levels of interleukin-1 beta, granulocyte-macrophage colony-stimulating factor, tumor necrosis factor-alpha, and interleukin-6 were detected in some, but not all, HCV patients and were in general undetectable in healthy subjects. Patients had significantly higher concentrations of neopterin (P = 0.0026), beta 2-microglobulin (P = 0.046), soluble interleukin-2 receptor (P = 0.021), and soluble CD8 (P < 0.039), than healthy controls; conversely, interferon-gamma levels were significantly lower (P = 0.023). Significant correlations were observed between beta 2-microglobulin concentration and Knodell's index (r = 0.638, P = 0.00045), the score of piecemeal necrosis (r = 0.572, P = 0.0023), and the degree of fibrosis (r = 0.527, P = 0.0056). Interleukin-2 levels correlated significantly with Knodell's index (r = 0.412, P = 0.037), and the degree of lobular cytolysis (r = 0.389, P = 0.048). According to therapeutic outcome, pretreatment levels of soluble CD8 were only significantly elevated (P = 0.042) in patients with a sustained biochemical response. On interferon-alpha treatment, the levels of beta 2-microglobulin, neopterin, and soluble interleukin-2 receptor increased significantly (P < 0.05), irrespective of therapy outcome. In summary, HCV patients have an altered immune reactivity that might play a role in the pathogenesis of chronic hepatitis C, and might influence the therapeutic outcome to interferon-gamma.

Interferon therapy in chronic hepatitis C virus infection

Antiviral treatment of chronic hepatitis C with interferon is reviewed. Alpha-interferon, both recombinant alpha-2a, -2b and human lymphoblastoid interferon given at a dose of > or = 3MU t.i.w. for 6-12 months will result in normalisation of ALT levels (complete response) in some 50-60% of treated patients with chronic hepatitis C virus (HCV) infection. Approximately half of the complete responders to interferon will relapse within 6 months once treatment is withdrawn (non-sustained response). Longer treatment schedules (6 vs. 12 months) seem to diminish the relapse rate and increase the percentage of sustained response. In patients with sustained response to interferon treatment with continuously normal ALT levels > or = 6 months after treatment stop a concomitant eradication of the viraemia is usually seen, whereas a non-sustained or non-response to interferon usually will indicate a continuous viraemia. Factors predictive of a favourable response are low pretreatment HCV RNA levels in serum, genotypes other than type II according to Okamoto, short disease duration, female gender and less pronounced liver damage, whereas high serum HCV RNA levels, having genotype II and cirrhosis, are predictive of a less favourable response. Patients with a sustained response and eradication of the viraemia will also improve their liver inflammation with diminishing scores for portal inflammation, piecemeal necrosis, lobular inflammation and also fibrosis after treatment. For non-responders and non-sustained responders to interferon, ribavirin especially in combination with interferon will offer some hope for the future.