A Phase II randomized controlled study to evaluate low-dose Interferon-alpha lozenge as maintenance therapy to prevent hepatitis C relapse
Chuan-Mo Lee1, Chi-Yi Chen2, Rong-Nan Chien3, Kuo-Chih Tseng4, Cheng-Yuan Peng5, Shui-Yi Tung6, Yi-Jen Fang7, Yi-Hsiang Huang8, Sheng-Nan Lu1, Chao-Hung Hung1, Tsung-Jang Tsai2, Jian-Zhong Fang2, Chao-Wei Hsu9, , Chau-Ting Yeh9 1 Department of Hepato-Gastroenterology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
2. Department of Hepato-Gastroenterology, Chiayi Christian Hospital, Chiayi , Taiwan.
3. Department of Hepato-Gastroenterology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.
4. Department of Hepato-Gastroenterology, Buddhist Dalin Tzu Chi General Hospital, Chiayi , Taiwan.
5. Department of Hepato-Gastroenterology, China Medical University Hospital, Taichung, Taiwan.
6. Department of Hepato-Gastroenterology, Chiayi Chang Gung Memorial Hospital, Chiayi , Taiwan.
7. Department of Hepato-Gastroenterology, Show-Chwan Memorial Hospital, Changhua, Taiwan.
8. Department of Hepato-Gastreoenterology, Taipei Veterans General Hospital, Taipei, Taiwan.
Abstract
Background and Aim
Previous studies demonstrated that low-dose oral interferon-alpha exerted an immune-modulating effect in animal and human diseases. This randomized, double blinded,
randomized, placebo-controlled study aimed to investigate the clinical efficacy of low-dose oral interferon-alpha in chronic hepatitis C patients having achieved virological clearance with pegylated interferon plus ribavirin therapy to prevent
hepatitis C virological relapse. Methods
169 One hundred and sixty-nine genotype 1b chronic hepatitis C patients receiving pegylated interferon plus ribavirin treatment and achieving end-of-therapy virological clearance were randomly assigned into one of the three study groups to receive 500 IU interferon-alpha lozenge once a day (Lowlow-dose group; n = 59), 500 IU
interferon-alpha lozenge three times a day (Highhigh-dose group; n = 53), or placebo (n = 57). The patients were treated for 24 weeks and followed for another 24 weeks. The side effect, overall relapse rate, the relapse rate in patients stratified by
fibroindex, and alterations of laboratory data were assessed. Results
Overall, no significant difference was found for the relapse rates in the three groups (30.5, 37.7, and 35.1%; P > 0.05). In subgroup analysis, it was found that patients with fibroindex 1.4 to 1.7, relapse occurred in 1/12 (8.3%) versus 9/21 (42.9%) patients (Lowlow-Dose dose versus non-Lowlow-dose subgroups; P = 0.05). Unexpectedly, in 158 patients who completed at least 4 weeks of treatment,
significantly higher platelet count was found in the Lowlow-dose group at the end of trial (Lowlow-Dose dose versus placebo, P < 0.005). In patients with
thrombocytopenia (platelet count < 150 ×103/microliter), a significantly expedited recovery of low platelet count after the end of peginterferon treatment was found in the Lowlow-dose group (P = 0.002). No drug-related severe adverse event was reported.
Summary
Low dose oral interferon is a safe and well-tolerated drug for hepatitis C patients. A Bborderline suppressive effect of virological relapse was observed in patients with mild liver fibrosis. A significantly expedited recovery of platelet count was found in thrombocytopenic patients.
Introduction
There are approximately 170 million people in the world currently infected with hepatitis C virus (HCV) in the world. Chronic hepatitis C virus infection leads to severe diseases such as decompensated cirrhosis and hepatocellular carcinoma. Previously, the standard treatment for chronic HCV infection was a combination of pegylated interferon and an oral administration of ribavirin. This combination is quite effective against genotype 2 and 3 HCV infection, but in patients infected with genotype 1, the sustained virological response rate (SVR) is not less satisfactory. Recently, several direct acting antiviral (DAA) agents (DAA) were developed. The first US food and drug administration approved DAAs are boceprevir and telaprevir. These are NS3/4A protease inhibitors. Combination of these agents with standard peginterferon plus ribaivirin therapy increases about 20% of in the SVR rate in genotype 1 chronic hepatitis C. Other DAAs targeted against other nonstructural proteins were are also under development. For example, the polymerase inhibitor, sofosbuvir, has achieved excellent end- of- therapy response when combined with peginterferon and ribavirin. However, relapses still occur after cessation of treatment. Other new strategies are now under clinical trials including pangenotypic DAAs and interferon-free oral combination regiments. Preliminary data showed promising results, but large scale phase III data are still pending.
A natural human interferon-alpha administered through oral mucosal route has been manufactured by Hayashibara Biochemical Laboratories (HBL) in Okayama, Japan. The same HBL interferon-alpha, formulated for parenteral use by other pharmaceutical companies, has been approved by the Japanese government for the treatment of renal cell carcinoma, chronic active hepatitis B, chronic hepatitis C and chronic myelogenous leukemia. HBL interferon-alpha has a molecular weight ranging from 16,000 to 25,000 daltons. It comprises a mixture of 2 subspecies of interferon-alpha derived from human lymphoblastoid cells (BALL-1 cells) induced by
Hemagglutinating Virus of Japan. HBL interferon-alpha lozenge is generated by mixing the bulk powder with anhydrous crystalline maltose and 0.5% of magnesium stearate. The product is stable at 4 to 30oC for an extended period of time.
Accumulated data suggest that administration of low doses interferon-alpha by oral mucosal route can exert protective systemic effects in animals. Various degrees of beneficial effects have also been reported in patients with acquired immune deficiency, chronic aphthous stomatitis, chronic hepatitis B, chronic hepatitis C, respiratory syncytial viral infection, Sjogren’s syndrome, and measles. The
mechanisms of these effects were are not clear. It has been postulated that low dose interferon-alpha may exert biological effects on the oral mucosa cells, which
subsequently induce systemic host defense mechanisms without interferon-alpha actually entering the circulation. In this view, the oral mucosa mediated interferon effect is totally different from the anti-HCV effect of the high dose pegylated interferon.
Regardless of the advance of anti-HCV treatments, relapses after the end of treatment remain a problem. With the upcoming strategy of interferon-free oral DAAs regiments, it can be expected that post treatment relapse maybe a continuous
challenge. In this phase II randomized controlled study, we examined the safety profile as well as the efficacy of low dose HBL interferon-alpha lozenge therapy to prevent the relapse during a 6-month treatment following peginterferon plus ribavirin treatment for genotype 1b HCV infected patients. A high dose treatment group and a placebo group were included for comparison.
Patients and Methods Study design
The objectives of this study were to evaluate the efficacy and safety of low-dose human IFN-alpha by the oral mucosal route in reducing the relapse rate in HCV patients who had achieved a complete virologic response to the combination therapy with pegylated IFN-alpha and oral ribavirin. This was a randomized, double blinded,
randomized, placebo-controlled, parallel study. Eligible subjects were randomized to placebo or one of the two treatment groups. The low-dose group received oral HBL alpha lozenge 500 IU once per day. The high-dose group received oral HBL IFN-alpha lozenge 500 IU three times per day. The treatment was given until relapse of HCV infection or continued for 24 weeks if no relapse occurred.
Inclusion and exclusion criteria
A subject was included in the study if he/she met all of the following criteria: (1) was at least 21 years of age, (2) was scheduled to complete hepatitis C treatment, consisting of pegylated interferon-alpha plus oral ribavirin, within 4 weeks, (3) had a negative serum HCV RNA within 4 weeks before the end of antiviralhepatitis C
treatment, (4) had HCV genotype Ib1b, and (5) was willing and able to comply with study procedures and sign informed consent. A subject was excluded from the study for any of the following reasons: (1) Child-Pugh stage B or C, (2) previous (< 5 years) or current history of malignancy, (3) participating in any other clinical trial or using any other investigational drug within 30 days of entry to this protocol, (4) had any other cause of the liver diseases, (5) had any history of decompensated liver function, (6) had uncontrolled diabetes or hypertension, (7) had significant renal function impairment (creatinine>1.5mg/dl), severe cardiac disease, or suspicion of a disease
or condition that might render the subject at high risk from this treatment, (8) had known hypersensitivity to any component of the study medication, (9) had a known substance abuse problem, (10) using any of the listed prohibited medications in protocol, (11) had a medical condition requiring anticoagulant or anti-platelet drugs, (12) a female of childbearing potential, and (13) had human immunodeficiency virus infection.
Efficacy analysis
Relapse was defined as undetectable serum HCV RNA at the end of
combination drug treatment followed by a positive HCV RNA test during follow-ups. SVR in this study was defined as undetectable serum HCV RNA 24 weeks after the end of oral HBL IFN-alpha lozenge (or placebo) treatment. The overall relapse rate as well as the relapse rate in patients stratified by fibroindex was evaluated.
Statistical Methods
Continuous variables were analyzed by analysis of variance (ANOVA) for comparing the difference among three groups and two sample T-test or Wilcoxon Rank Sum test for comparing the difference between two groups. Chi-square test or Fisher’s exact test was used to compare the difference for categorical variables. All statistical assessments would be evaluated at the significance level of alpha = 0.05. Results
Basic clinical data of patients included
Totally 169 patients were included. Of them, 59, 53, and 57 patients were randomly assigned to the Lowlow-dose (500 IU), Highhigh-dose (1500 IU), and placebo groups. The basic clinical data were are listed in Table 1. No statistical difference was found in terms of age, gender, biochemistry data, and hemogram data. However, a small slightly but significantly higher body mass index (BMI) was observed in the placebo group (P = 0.038). Previous peginterferon plus ribavirin treatment period was 7.2 ± 2.6, 7.7 ± 2.9, and 7.7 ± 3.0 months, respectively, for the three groups of patients (P = 0.805). In this study, liver biopsy was not performed for all patients. Thus, fibroindex was evaluated at the end of peginterferon treatment (before the start of oral HBL interferon-alpha treatment).
Fibroindex = 1.738 – 0.064 × platelet (×104/mm3) + 0.005 × AST (IU/L) + 0.463 ×gamma-globulin (g/dL)
The fibroindex was 1.82 ± 0.45, 1.79 ± 0.56, and 1.87 ± 0.59, respectively, for the three groups of patients (P = 0.986).
Efficacy of oral HBL interferon-alpha in reducing preventing HCV relapse Overall, relapse of HCV infection occurred in 18 (30.5%), 20 (37.7%), and 20 (35.1%) of low-dose, high-dose and placebo groups, respectively (P = 0.716). The patients were then stratified by fibroindex into four subgroups (fibroindex <1.40, 1.4 to 1.7, 1.7 to 2.0 and 2.0) (Table 2). It was found that in patients with fibroindex ≧ between 1.4 and 1.7, relapse of HCV infection occurred in 1/12 (8.3%), 4/9 (44.4%), and 5/12 (41.7%) patients for the Lowlow-dose, Highhigh-dose, and placebo groups
respectively. The Lowlow-dose group had a borderline significantly lower relapse rate
when compared with the other two groups combined (P = 0.05).
Effect of oral HBL interferon-alpha on biochemistry and hemogram data changes
Biochemistry data and hemogram data were reviewed at 24 (end-of-oral interferon treatment) and 48 weeks (end-of-follow up) after the start of oral HBL interferon-alpha. A small but significant decrease of bilirubin levels between the Highhigh-dose and placebo groups was found at week-24 and week-28 (0.09 ± 0.30 and 0.08 ± 0.24 mg/dL,of decrease respectively; P = 0.027 and 0.004). No other significant changes were observed for other biochemistry data. Interestingly, a significant difference of the absolute platelet count was found between the Lowlow-dose and placebo groups, when reviewing the hemogram data. While the initial platelet counts were not
significantly different between the three groups (Table 1, P = 0.283), the subsequent platelet counts were 186.9 ± 50.4 vs. 164.6 ± 58.4 ×103/microL (Lowlow-dose vs. placebo; P = 0.030) and 190.7 ± 54.9 vs. 169.6 ± 58.7 ×103/microL (Lowlow-dose vs. placebo; P = 0.047) at week-24 and week-48, respectively.
Effect of oral HBL interferon-alpha on platelet count recovery
Because in some of our patients, relapse of HCV occurred shortly after the start of oral interferon, a very short duration of oral interferon treatment was given to them. To understand better the effect of oral interferon on platelet count recovery, we thus reviewed the data in only the patients receiving at least 4 weeks of oral interferon. The data were are summarized in Table 3. Totally, 55, 48, and 55 patients in the three groups received oral interferon for more than 4 weeks. The results were similar to those of total patient analysis and the difference was even more significant. In week
-48, the platelet counts were 203.4 ± 52.7 vs. 167.6 ± 59.0 ×103/microL in Lowlow -dose vs. placebo groups (P = 0.003). Interestingly, no difference was found between the Highhigh-dose and placebo groups (P = 0.96).
Despite that there was no statistical difference of in the initial platelet counts
×103/microL; P = 0.10), the numerically higher mean platelet count might cast some doubt as to whether the expedited platelet count recovery was due to a higher initial platelet count. To resolve this issue, only patients with initial platelet counts < 150 ×103/microL were included for calculation. Totally, 28, 32, and 35 patients met the criteria. The initial platelet counts were 110.9 ± 26.0, 101.8 ± 26.7, and 103.0 ± 31.8, ×103/microL, respectively. It was found that the expedited platelet count recovery was still observed, Low in the low-dose versus placebo group (P = 0.002 at week-48; Figure 2). Notably, in the Lowlow-dose group, the mean platelet count recovered to 183.2, whereas in the other two groups, the mean platelet counts only recovered to 140.2 and 146.0, respectively, still < 150 ×103/microL (Figure 2).
Safety
Comparing Compared with the placebo group, no significant increase of in the
adverse events was found. In fact, 11 (18.6%), 7 (13.2%), and 13 (22.8%) of adverse events were reported for Lowthe low-dose, Highhigh-dose, and placebo groups, respectively (Table 4). The adverse events appeared appearing only in the treatment groups but not in the placebo group were: tonsillitis (1), upper respiratory tract infection (1), arthralgia (1), peripheral neuropathy (1), anxiety (1), altered mood (1), alopecia (1), and rash (1). All were self-limited and mild. The adverse events could also be residual side effects derived from prior peginterferon treatment. No drug related severe adverse event was reported.
Discussion
It has always been questioned whether low dose oral interferon can exert any pharmacological effect in human. One major reason for such doubt comes from the demonstration of potent antiviral effect using regular or pegylated interferon. A subcutaneous administration of millions of IU is required to achieve antiviral effect in human. In comparison, 250-500 IU of interferon through mucosa route seems unlikely to have any pharmacological effect. However, accumulated evidence indicated that low dose interferon by oral route could exhibit some immune modulating function in animal and human diseases. In this study, we tested whether the low dose interferon-alpha lozenge exerted any effect in the inhibition of HCV relapse after peginterferon-based therapy. Our data indicated a possible suppressive effect for HCV relapse in patients with fibroindex between 1.4 and 1.7. Such effect was not seen in patients with fibroindex > 1.7, suggesting that in patients with more established liver fibrosis or cirrhosis, this effect disappeared. Because of the stratification according to
fibroindex, only a small number of patients were included for each subgroup. A larger scale of study focusing on patients with mild fibrosis is needed to further clarify this
issue.
When analyzing the biochemistry and hemogram data, we were surprised to findfound that the platelet count recovered more rapidly in the Lowlow-dose group. One of the major side effects for pegylated interferon treatment was the occurrence of thrombocytopenia. The platelet count decreased progressively until the end of
treatment, followed by a slow recovery. This adverse effect was even more severe in patients with advanced fibrosis or cirrhosis. In this study, we discovered that low-dose interferon could expedite the recovery of platelet count and thus potentially reduced the risk of gastrointestinal hemorrhage. Such effect remained prominent in patients with post treatment thrombocytopenia (platelet count < 150 ×103/microL) suggesting a possible clinical role.
An interesting observation for both the HCV-relapse-suppression suppressing
effect and platelet-count-recovery-expediting effect was that they only appeared in the
Lowlow-dose group. Both effects were not seen in the Highhigh-dose and placebo groups. These results strongly argued for the view that there was is an immune modulating pathway mediated by low dose oral interferon through mucosa route and this pathway was is independent of the antiviral effect of the high dose pegylated interferon antiviral effect. Previous studies have suggested elicitation of systemic immune responses through mucosa-mediated route. In immune responses mediated by intestinal mucosa, it was found that humoral immune responses to antigens in contact with intestinal mucosa are mostly of immunoglobulin A class in secretory form with different degrees of immunoglobulin G class responses. Interestingly, the mucosal immune response could induce systemic T cell hyporesponsiveness to certain immunological reactions. It is believed that the lymphoid cells in the mucosal sites release lymphokines through antigen recognition, thereby regulating regional as well as systemic T cells function. Furthermore, the liver is the major site for removal of IgA immune complexes and thus plays a role in regulating mucosa mediated immune process. Other studies on gut mucosal vaccines also showed that induction of
immunity in the gastrointestinal mucosa through oral immunization resulted in
complex cross-talkcrosstalk between mucosal and systemic immunity. Despite our extensive knowledge of mucosa mediated immune responses in pathogen or vaccine induced immunity, the immunological changes following oral interferon
administration are largely unknown. Judging from our present results, there is surely a prominent systemic effect. Further studies should be conducted to illustrate the molecular and cellular mechanisms.
In summary, oral HBL interferon-alpha is a safe drug for chronic hepatitis C patients having received peginterferon and ribavirin therapy. Patients received low dose (500 IU) oral HBL interferon-alpha significantly expedited the platelet count
recovery, compared with the high does and placebo groups. In patients with mild fibrosis subgroup (fibroindex 1.4 to 1.7), low dose HBL oral interferon-alpha might be able to reduce the HCV relapse rate. A large scale trial is needed to illustrate confirm this pointobservation.
