Clinical and Pathological Features of Clevudine Induced Myopathy

BACKGROUND: Clevudine (Revovir(R)) is a recently introduced antiviral drug, and clinical trials have demonstrated its potent, sustained antiviral activity without specific adverse events. However, several studies have found severe myopathy during clevudine therapy. Our study aimed to summarize the clinical and pathological features of clevudine-induced myopathy. METHODS: We analyzed the demographic data, clinical features, and pathologic findings of 18 consecutive hepatitis-B patients who developed skeletal myopathy during clevudine therapy. RESULTS: The 18 patients comprised 11 women and 7 men aged 48.2+/-14.0 years (mean+/-standard deviation; range 28-74 years). Each of the 18 patients was treated with clevudine for at least 5 months (range 5-20 months) before the development of symptoms. In all patients the main symptom was proximal muscular weakness that progressed slowly over several months. Elevated creatine kinase and myopathic patterns on electromyography were found. Muscle biopsies revealed severe myonecrosis associated with numerous ragged red fibers and cytochrome-c-oxidase-negative fibers, mitochondrial proliferation, and predominant type-II fiber atrophy. The muscle weakness gradually improved within 20 weeks after discontinuation of clevudine. CONCLUSIONS: Clevudine therapy can induce myopathy associated with mitochondrial toxicity. Careful clinical and laboratory monitoring of the skeletal muscle dysfunction is required in patients receiving clevudine therapy.

Antiviral Effect of Entecavir Switching Therapy in Chronic Hepatitis B Patients with Clevudine-associated Myopathy / 대한소화기학회지

No abstract available.

Efficacy of Entecavir Switching Therapy in Chronic Hepatitis B Patients with Clevudine-induced Myopathy / 대한소화기학회지

BACKGROUND/AIMS: Clevudine is a potent antiviral agent against HBV. However, long-term clevudine therapy may cause myopathy. This study was carried out to identify the efficacy of entecavir switching therapy in chronic hepatitis B patients experiencing clevudine-induced myopathy. METHODS: One hundred forty six patients with chronic hepatitis B treated with 30 mg of clevudine per day for 73 weeks (range, 36-132 weeks) were enrolled. Among them, clevudine-induced myopathy occurred in 21 patients (14.4%) which was diagnosed if the patients had symptoms related to myopathy with concurrent CK and AST elevation. All the patients who were diagnosed as clevudine-induced myopathy stopped the therapy, and 17 patients (81%) were switched to entecavir 0.5 mg. RESULTS: The patients with clevudine-induced myopathy were switched to entecavir 0.5 mg for median 68 weeks, and all of them showed disappearance of clinical myopathic symptoms and normalization of CK and AST level within median 2.2 months. Eight patients (47%) were HBeAg positive before entecavir treatment, and HBeAg seroconversion was achieved in 2 patients (25%). HBV DNA level was elevated in 3 patients (17.6%) at the time when the patients were diagnosed as myopathy, all of them achieved virological response with entecavir switching therapy. ALT level was elevated in 3 patients (17.6%) before entecavir treatment, all of them showed normalization of ALT level. During entecavir therapy, genotypic resistance to entecavir or virological breakthrough was not noted. CONCLUSIONS: In chronic hepatitis B patients experiencing clevudine-induced myopathy, switching to entecavir 0.5 mg per day showed a resolution of myopathy and adequate viral suppression.

Experience of Anti-Viral Therapy in Hepatitis B-Associated Membranous Nephropathy, Including Lamivudine-Resistant Strains

BACKGROUND/AIMS: Chronic hepatitis B infection is a common cause of secondary membranous nephropathy (MN) in endemic areas. Lamivudine treatment improves renal outcome in patients with hepatitis B virus-associated MN (HBV-MN), but prolonged use leads to the emergence of lamivudine-resistant variants. We describe our experience treating lamivudine-resistant and other strains of HBV-MN with new antiviral drugs. METHODS: Of the 89 patients biopsied and diagnosed with MN from 1996 to 2011, 10 positive for hepatitis B surface antigen were recruited for this study. We investigated the clinical courses, therapeutic responses, and prognoses of patients with HBV-MN. RESULTS: The incidence of HBV-MN among the original 89 patients was 11.2%. Of these patients, four were treated with supportive care and six with antiviral drugs. One of the four patients treated with supportive care had a spontaneous remission. Four of the six patients treated with antiviral drugs were given lamivudine, and the other two were given entecavir. Two of the four patients treated with lamivudine achieved complete remission with seroconversion (i.e., development of anti-hepatitis B e antigen antibodies), whereas the other two had lamivudine-resistant strains, which were detected at 22 and 23 months after lamivudine treatment, respectively. We added adefovir to the treatment regimen for one of these patients, and for the other patient we substituted clevudine for lamivudine. Both of these patients experienced complete remission, as did the two patients initially treated with entecavir, neither of whom showed resistance to the drug. CONCLUSIONS: New nucleoside analogues, such as entecavir, adefovir, and clevudine, can be effective for treatment of HBV-MN, including lamivudine-resistant strains.

Long-Term Treatment Efficacy and Safety of Clevudine Therapy in Naive Patients with Chronic Hepatitis B

BACKGROUND/AIMS: Clevudine (CLV) has potent antiviral activity against chronic hepatitis B (CHB) virus infection. The long-term efficacy and safety of CLV therapy in naive patients with CHB were investigated. METHODS: In this retrospective study, 152 naive Korean patients with CHB who received 30 mg of CLV once daily for at least 12 months were investigated. RESULTS: The cumulative rates at months 12, 24, and 36, respectively, were 65.8%, 74.7%, and 74.7% for undetectable serum hepatitis B virus (HBV) DNA ( or =6 log10 IU/mL (p=0.032) and detectable serum HBV DNA (> or =12 IU/mL) at week 24 (p=0.023) were independently associated with the development of viral breakthrough. During follow-up, CLV-induced myopathy developed in 5.9% of patients. CONCLUSIONS: The results of long-term CLV therapy for the treatment of naive patients with CHB showed a high frequency of antiviral resistance and substantial associated myopathy. Therefore, we advise that CLV should not be used as a first-line treatment for naive patients given the availability of other more potent, safer antiviral agents.

Clinical and Virological Responses to Clevudine Therapy of Hepatocelluar Carcinoma Patients with Chronic Hepatitis B

BACKGROUND/AIMS: The clinical effects of clevudine have been reported in patients with chronic hepatitis B virus infections (CHIs). In this investigation, we assessed whether clevudine induced biochemical and virological improvements in hepatocellular carcinoma (HCC) patients with CHI. METHODS: Fifty-four patients who received 30 mg clevudine for more than 24 weeks between 2007 and 2009 at the National Cancer Center Hospital, Korea, were enrolled. Among these cases, 39 had HCC (CHI/HCC group) and 15 did not (CHI group). RESULTS: In relation to the CHI group, the CHI/HCC group was older (55.5 years.) and had a higher liver cirrhosis rate (79.5%) (p0.05). Liver function was preserved with clevudine treatment in patients displaying response or stable disease under anti-cancer therapy. Four patients (7.4%) developed viral resistance during clevudine therapy. Among these, one was naive, and three had previously received antiviral therapy. One CHI/HCC patient (1.9%) discontinued clevudine treatment due to symptomatic myopathy. CONCLUSIONS: Our findings clearly indicate that clevudine has comparable antiviral and biochemical effects in patients with CHI and with CHI/HCC and preserves the underlying liver function in HBV-related HCC patients.

Comparison of entecavir and clevudine for treatment of chronic hepatitis B / 대한내과학회지

BACKGROUND/AIMS: Entecavir (ETV) and clevudine (CLV) are potent inhibitors of hepatitis B virus (HBV) DNA polymerase and have demonstrated clinical efficacy. No comparative study has reported on these two medications among patients with naive chronic hepatitis B (CHB). We assessed the clinical outcome of CHB patients treated with either ETV or CLV. METHODS: A nonrandomized comparative study was conducted retrospectively. The clinical results from treatments of either 0.5 mg ETV (n=56) or 30 mg CLV (n=45) were analyzed during a 1 year period. The median reduction in serum HBV DNA, undetectable HBV DNA, HBeAg seroconversion, and normalization of alanine transaminase (ALT) were compared between the two groups. RESULTS: After 1 year on antiviral therapy, the median reduction in serum HBV DNA from baseline to the endpoint was greater in patients in the ETV group than in those in the CLV (5.73 vs. 4.5 log copies/mL, p=0.009) group. ALT normalization occurred in 85.5% (47/55) of the ETV cases and 77.3% (34/40) of the CLV cases (p=0.215). HBV DNA was undetectable in 80.0% (44/55) of the ETV group and 78.0% (32/41) of the CLV group (p=0.505). HBeAg seroconversion occurred in 15.4% (6/39) of those administered ETV and in 14.3% (4/28) administered CLV (p=0.593). Within 12 months, a virological breakthrough was documented in three patients undergoing CLV treatment, and CLV-related myopathy developed in three other patients. CONCLUSIONS: ETV and CLV showed excellent antiviral effects in patients with CHB. ETV was superior for viral suppression and showed fewer side effects than CLV.

A YIDD Mutation in a Case of Recurrent Hepatitis B after Liver Transplantation Induced by an S-escape Mutant

A 47-year-old woman underwent orthotopic liver transplantation (OLT) for hepatitis B virus (HBV)-related end-stage liver cirrhosis. The patient received hepatitis B immunoglobulin prophylaxis after OLT. Despite the protective level of the serum anti-hepatitis-B surface antibody, HBV recurred at 22 months post-OLT and induced subacute hepatic failure. The pre-OLT HBV genome contained a complex mutation pattern in overlapping frame regions of the surface (S) and polymerase (P) genes, which is the same mutation pattern as seen in post-OLT HBV DNA. G145R and K141R mutations in the "a" determinant were detected only in the post-OLT sample. Clevudine (30 mg once daily) was administered for recurrent hepatitis B. Hepatitis B was reactivated with a flare-up, and a M204I mutation (YIDD mutant type) appeared with a higher viral load at 9 months after clevudine treatment. We report here a case of a YIDD mutation that developed in recurrent hepatitis B after OLT induced by an S-escape mutant.

Forty-eight weeks treatment with clevudine 30 mg qd versus lamivudine 100 mg qd for chronic hepatitis B infection: a double-blind randomized study / 대한간학회지

BACKGROUND/AIMS: Clevudine is a pyrimidine analogue with potent activity against hepatitis B virus (HBV) replication in vitro. In a previous pivotal phase III clinical study, 24 weeks treatment with clevudine 30 mg has been shown to profoundly suppress HBV replication and normalize serum alanine aminotransferase level. METHODS: In this study, we compare the efficacy and safety of clevudine (30 mg daily) versus lamivudine (100 mg daily) for 48 weeks in treatment-naive chronic hepatitis B e antigen (HBeAg) positive patients. RESULTS: Ninety-two chronic HBeAg positive patients were randomized to receive clevudine 30 mg daily or lamivudine 100 mg daily in a 1:1 ratio. The clevudine group demonstrated greater viral suppression at week 48 when compared with the lamivudine group (median reduction: 4.27 vs. 3.17 log(10) copies/ml at week 48, p<0.0001). At week 48, serum HBV DNA level was below 300 copies/mL in 73% and 40% in the clevudine and lamivudine groups, respectively (p=0.001). HBeAg seroconversion occurred in 18% of patients in the clevudine group versus 12% in the lamivudine group at week 48. Lamivudine-resistant mutations were detected in 11 (24%) patients in the lamivudine group, who showed viral rebound during lamivudine therapy but no resistance was found in the clevudine group during 48-week treatment period. CONCLUSIONS: A 48-week dosing with clevudine 30 mg daily was superior to lamivudine 100 mg daily in suppressing HBV replication, with no emergence of viral breakthrough in patients with HBeAg positive chronic hepatits B.

Clevudine induced diabetes mellitus in a patient with chronic hepatitis B / 대한내과학회지

Several studies have documented that various agents can induce diabetes mellitus, such as steroids, thiazides, anti-psychotic agents, and anti-viral agents. Many antiviral agents are also reported to impair insulin resistance and induce diabetes mellitus in patients infected with human immunodeficiency virus (HIV). However, there are no reports of diabetes mellitus induced by clevudine, one of the antiviral agents used to treat chronic hepatitis B virus (HBV) infection. We report a case of diabetes mellitus induced by clevudine in a patient with chronic hepatitis B.

Treatment Outcomes of Clevudine versus Lamivudine at Week 48 in Naive Patients with HBeAg Positive Chronic Hepatitis B

The authors assessed the efficacy and antiviral resistance of 48-week clevudine therapy versus lamivudine in treatment of naive patients with HBeAg positive chronic hepatitis B. In this retrospective study, a total of 116 HBeAg positive patients, who received 30 mg of clevudine once daily (n=53) or 100 mg of lamivudine once daily (n=63) for 48 weeks, were included. At week 48, clevudine therapy produced a significantly greater mean reductions in serum HBV DNA levels from baseline than lamivudine therapy (-5.2 vs. -4.2 log(10)IU/mL; P=0.005). Furthermore, a significantly higher proportion of patients on clevudine achieved negative serum HBV DNA by PCR (<13 IU/mL) at week 48 (60.4% vs. 38.1%; P=0.025). The incidence of virologic breakthrough in the clevudine group was significantly lower than in the lamivudine group (9.4% vs. 25.4%; P=0.031). However, rates of alanine aminotransferase normalization and HBeAg loss or seroconversion were similar in the two groups (83.0% vs. 81.0%, 11.3% vs. 11.1%; P=0.813, 1.000, respectively). In conclusion, clevudine is more potent for viral suppression and lower for antiviral resistance at week 48 than lamivudine in treatment of naive patients with HBeAg positive chronic hepatitis B.

Efficacy of Initial Treatment with Clevudine in Naive Patients with Chronic Hepatitis B

BACKGROUND/AIMS: Clevudine, a pyrimidine nucleoside analogue, has potent antiviral effects in patients with chronic viral hepatitis B (CHB). We report the efficacy of initial treatment with clevudine in naive patients with CHB living in Daejeon and Chungcheong Province, South Korea. METHODS: One hundred five adults with CHB were administered 30 mg of clevudine per day for an average of 51 weeks. We evaluated viral markers and liver biochemistry retrospectively every 3 months. RESULTS: Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and hepatitis B virus (HBV) DNA before the treatment were 184 +/- 188 IU/L, 150 +/- 138 IU/L, and 7.1 +/- 1.2 log copies/mL, respectively. Undetectable rates (< 60 IU/mL) of DNA were 36.2%, 68.9%, 83.6%, 76.2%, and 75.8% at 12, 24, 36, 48, and 60 weeks, respectively. Seroconversion rates were 9.1%, 13.6%, 24.6%, 26.5%, and 26.1% and ALT normalization rates were 64.5%, 78.1%, 87.9%, 90.0% at 12, 24, 36, and 48 weeks, respectively. Six patients (5.7%) had a viral breakthrough. CONCLUSIONS: Clevudine is a useful drug in the initial treatment of patients with CHB, with a potent antiviral effect and low incidence of viral breakthrough.

Treatment Efficacy of Clevudine, Entecavir and Lamivudine in Treatment-naive Patients with HBeAg-Positive Chronic Hepatitis B / 대한소화기학회지

BACKGROUND/AIMS: Clevudine is a potent antiviral agent that has demonstrated efficacy in patients with chronic hepatitis B. This study compared the efficacy of clevudine (C), entecavir (E) and lamivudine (L) in treatment-naive patient with HBeAg-positive chronic hepatitis B. METHODS: A total of 146 treatment-naive patients with HBeAg-positive chronic hepatitis B received clevudine, entecavir or lamivudine. C group (n=39) received 30 mg of clevudine, E group (n=39) received 0.5 mg of entecavir and L group (n=68) received 100 mg of lamivudine once a day for more than 48 weeks. The efficacy analysis estimated the mean changes of the HBV DNA levels as a virologic response, the normalization of the ALT levels (less than 35 IU/L) as a biochemical response and loss of HBeAg or seroconversion as a serologic response. The serum HBV DNA level was quantified by hybrid capture and real-time PCR assay. RESULTS: Before the administration of clevudine, entecavir and lamivudine, the mean HBV DNA and ALT levels and the gender and age were well balanced among the three groups (p>0.05). For the virologic response at 48 weeks, the mean changes of the HBV DNA levels from baseline of the C, E and L groups were -3.8+/-2.2, -4.5+/-1.9 and -2.5+/-2.1 log copies/mL. C and E group showed superior antiviral activity compared to that of L group (p0.05). Viral breakthrough in C group was noted at 24 weeks (5%) and 48 weeks (21%), but no biochemical breakthrough was noted. The elevation of the serum CK level was noted in only 1 patient of group C at 48 weeks (2.56%) after therapy. For the patients without or with liver cirrhosis (LC), C and E group showed superior antiviral activity compared to that of the L group, but the antiviral activity was more effective in non- LC group than LC group (p<0.0001 vs p=0.036). CONCLUSIONS: Clevudine therapy compared with lamivudine for 48 weeks showed significantly potent antiviral efficacy in treatment-naive patients with HBeAg-positive chronic hepatitis B, and especially in the non-LC patients. However, the antiviral efficacy of clevudine was similar to that of entecavir even though taking into account relatively short follow up period and retrospective study.

Clevudine therapy in patients with chronic hepatitis B / 대한간학회지

No abstract available.

Long-term clevudine therapy in nucleos(t)ide-naive and lamivudine-experienced patients with hepatitis B virus-related chronic liver diseases / 대한간학회지

BACKGROUNDS/AIMS: Clevudine is an effective antiviral nucleoside analogue, but there are few data regarding its long-term effects, resistance, and safety. The aim of this study was to evaluate the long-term clinical efficacy of clevudine over a 1-year treatment period in nucleos(t)ide-naive and lamivudine-experienced chronic hepatitis B patients. METHODS: Nucleos(t)ide-naive (group A, n=196) and lamivudine-experienced (serum hepatitis B virus, HBV DNA >2,000 copies/mL without resistant mutants at the start of clevudine therapy, group B, n=75) patients were included in this study. Basic clinical characteristics including age, sex, the presence of cirrhosis, laboratory data, and hepatitis B surface antigen (HBeAg) positivity were similar between the two groups. Pretreatment serum levels of HBV DNA were 7.4 and 6.6 log10 copies/mL (P<0.001). The mean treatment duration was 8 months for both groups (range for group A: 3-21 months; range for group B: 3-20 months). Genotypic analysis for resistant mutations in the reverse transcriptase of HBV was performed after viral breakthrough. RESULTS: After 1 year of therapy, 75.0% and 51.9% of groups A and B, respectively, had HBV DNA levels of <2,000 copies/mL (P=0.032), and HBeAg seroconversion rates were 16.9% and 16.7%, respectively. The rates of viral breakthrough at 1 year were 10.0% (8/80) and 44.4% (12/27), respectively (P<0.001). Proven sites of mutation of HBV DNA polymerase in naive patients were, for example, L80I, L180M, A181V/T, M204I and V207I. Ten patients complained of prominent fatigue and revealed elevated serum levels of aspartate aminotransferase (AST) and creatine phosphokinase (CPK). Two of these patients presented with severe myopathy from which they recovered completely after quitting clevudine. CONCLUSIONS: Clevudine is one of the recommended first-line medicines for the treatment of chronic hepatitis B, but it is not free from resistance, particularly in patients with a history of previous lamivudine treatment, but also in naive patients. Clevudine should be avoided in previously lamivudine-exposed patients. In addition, reelevation of serum AST and CPK levels is not a rare occurrence, and close observation and follow-up tests are essential.

Efficacy of 48-week clevudine therapy for chronic hepatitis B / 대한간학회지

BACKGROUND/AIMS: Clevudine is a nucleoside analogue that exhibits potent and sustained antiviral effects as a 24-week therapy for chronic hepatitis B (CHB). This study evaluated the efficacy and viral resistance of a 48-week course of clevudine treatment for CHB. METHODS: Data on patients with CHB and detectable serum hepatitis B virus (HBV) DNA who were treated with clevudine for 48 weeks or longer were collected retrospectively for this study. Patients who had taken lamivudine within the 3 years prior to this study were excluded. Serum HBV DNA was measured by polymerase chain reaction hybridization (lower detection limit=316 copies/mL). Serum HBV DNA and biochemical data were analyzed at weeks 24 and 48. Developments of viral breakthrough and resistance to the antiviral drug were also monitored. RESULTS: Data from 74 patients (mean age 44 years; M:F=54:20; HBeAg-positive, 47; HBeAg-negative, 27) were included in this study. Ten patients had experienced previous lamivudine treatment. Median HBV DNA at baseline was 6.49 log10 copies/mL. Median serum HBV DNA reductions from baseline at week 48 were -4.34 log10 copies/mL (HBeAg-positive, -4.84 log10 copies/mL; HBeAg-negative, -3.74 log10 copies/mL). At week 48, serum HBV DNA was not detected in 83.8% of the patients (HBeAg-positive, 76.6%; HBeAg-negative, 96.3%). Normalization of serum alanine aminotransferase levels was achieved in 84.7% of the patients. Viral breakthrough and antiviral resistance developed in two patients at week 48. The development of antiviral resistance was associated with the presence of previous lamivudine treatment and cirrhosis. CONCLUSION: A 48-week course of clevudine therapy was highly effective in patients with CHB. The risk of development of resistance to clevudine was increased in patients with previous exposure to lamivudine and cirrhosis.

Antiviral Therapy for Chronic Hepatitis B

Chronic hepatitis B infection is the most common cause of chronic liver diseases in Korea and can induce chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. If patients have significant viral replication and persistent abnormal liver function and/or significant liver pathology, antiviral agents can be administered to prevent progression of the disease. Each antiviral agent shows different antiviral efficacy, resistance rate, and adverse events. Interferon alpha and pegylated interferon alpha have the advantage of relative short duration of treatment, however show high incidence of adverse events. Lamivudine has significant long-term data indicating the prevention of disease progression, but shows high resistance rate. Clevudine, entecavir, telbivudine, and tenofovir show high antiviral efficacy, however clevudine shows only short-term data, entecavir shows carcinogenesis in mouse, telbivudine shows relatively high resistance rate. In addition, clevudine and telbivudine show myopathy, and adefovir and tenofovir show renal toxicity as adverse events. AASLD and EASL guideline advise pegylated interferon alpha, entecavir, and tenofovir as first line treatment, which show high antiviral efficacy and low resistance rate. KASL and APASL guideline permits the use of all antiviral agents because of their respective advantage and problems as mentioned above. If resistance occurs during first line therapy, add-on therapy should be performed to prevent resistance of to second line antiviral agents. Ideal antiviral agents have to show high antiviral efficacy, low resistance rate, no significant adverse events and their effect on prevention of disease progression must be supported with a long-term data.

Myopathy due to Chronic Clevudine Therapy: A Case Report

A 40-year-old man with chronic hepatitis B complained of progressive weakness of the proximal muscles and edema of both legs. He had been receiving long-term clevudine (nucleoside analogue reverse transcriptase inhibitor, NRTI) therapy for his hepatitis. The serum creatine kinase level was increased on the laboratory tests. His electromyography showed a generalized myopathic process. The muscle biopsy showed numerous ragged-red fibers, degenerating myofibers with variable sized cytoplasmic bodies, the prominence of type 1 fibers with type 2 fiber atrophy and an endomysial mononuclear cell infiltration. The electron microscopic examination revealed necrotic myofibers, including extremely dysmorphic mitochondria with extensive loss, blunting and focal clumping of the cristae and concentric cristae. Although clevudine is known to be a less cytotoxic agent among the various NRTIs, careful clinical attention should be paid to the patients who are receiving long-term clevudine therapy for the occurrence of myopathy.

Small Animal PET Imaging with 124IFIAU for Herpes Simplex Virus Type 1 Thymidine Kinase Gene Expression in a Hepatoma Model / 핵의학분자영상

PURPOSE: The HSV1-tk gene has been extensively studied as a type of reporter gene. In hepatocellular carcinoma (HCC), only a small proportion of patients are eligible for surgical resection and there is limitation in palliative options. Therefore, there is a need for the develoopement of new treatment modalities and gene therapy is a leading candidate. In the present study, we investigated the usefulness of substrate, 2'-fluoro-2'-deoxy-1-beta-D-arabino-furanosyl-5-[124/125I]iodo- uracil ([124/125I]FIAU) as a non-invasive imaging agent for HSV1-tk gene therapy in hepatoma model using small animal PET. MATERIAL AND METHODS: With the Morris hepatoma MCA cell line and MCA-tk cell line which was transduced with the HSV1-tk gene, in vitro uptake and correlation study between [125I]FIAU uptake according to increasing numeric count of percentage of MCA-tk cell were performed. The biodistribution data and small animal PET images with [124I]FIAU were obtained with Balb/c-nude mice bearing both MCA and MCA-tk tumors. RESULTS: Specific accumulation of [125I]FIAU was observed in MCA-tk cells but uptake was low in MCA cells. Uptake in MCA-tk cells was 15 times higher than that of MCA cells at 480 min. [125I]FIAU uptake was linearly correlated (R2=0.964, p=0.01) with increasing percentage of MCA-tk numeric cell count. Biodistribution results showed that [125I]FIAU was mainly excreted via the renal system in the early phase. Ratios of MCA-tk tumor to blood acting were 10, 41, and 641 at 1 h, 4 h, and 24 h post-injection, respectively. The maximum ratio of MCA-tk to MCA tumor was 192.7 at 24 h. Ratios of MCA-tk tumor to liver were 13.8, 66.8, and 588.3 at 1 h, 4 h, and 24 h, respectively. On small aninal PET, [124I]FIAU accumulated in substantial higher levels in MCA-tk tumor and liver than MCA tumor. CONCLUSION: FIAU shows selective accumulation to HSV1-tk expressing hepatoma cell tumors with minimal uptake in normal liver. Therefore, radiolabelled FIAU is expected to be a useful substrate for non-invasive imaging of HSV1-tk gene therapy and therapeutic response monitoring of HCC.

Management of Chronic Hepatitis B in Treatment-Naive Patients / 대한소화기학회지

Chronic hepatitis B (CHB) is a serious health problem in Korea. The natural history of chronic HBV infection has been divided into 4 phases: immune tolerance, immune clearance, inactive HBsAg carrier state and reactivation. During the phases of immune tolerance and inactive HBsAg carrier state, no treatment is required. Patients in the immune clearance or reactivation phases are candidates for therapy. In the last years, treatment effects of CHB have considerably improved. Several agents are currently approved for the treatment of CHB: interferon alpha, pegylated interferon alpha, lamivudine, adefovir, entecavir, telbivudine and clevudine in Korea. The treatment recommendations from the 2004 Korean Association for the Study of the Liver guideline on the management of CHB have been updated to incorporate new therapeutic options. What is uncertain is which agent or combination of agents is most effective, how long therapy should last, and which criteria should be used to start, continue, switch or stop therapy. Issues for consideration include efficacy, safety and incidences of resistance, and method of administration of antiviral therapy in treatment-naive patients.