Efficacy and safety of lamivudine on replication of recurrent hepatitis B after cadaveric renal transplantation

Lamivudine is effective for the treatment of reactivation of hepatitis B virus and fulminant hepatic failure in renal transplant recipients

Lamivudine is a potent inhibitor of hepatitis B virus (HBV) replication. The aim of this study is to elucidate the effectiveness of lamivudine for the treatment of HBV reactivation with or without fulminant hepatic failure in renal transplant recipients. Forty-two renal transplant recipients (30 men, 12 women) were enrolled onto this study. Eight patients presented with HBV reactivation without fulminant hepatic failure and were administered lamivudine (group I), 5 patients presented with HBV and hepatic failure and were administered lamivudine (group II), 5 patients presented with HBV and hepatic failure but were not administered lamivudine (group III), and 24 patients were asymptomatic HBV carriers who were not administered lamivudine (group IV). Lamivudine was administered at a dose of 100 or 150 mg once daily. A greater prevalence of recent use of a combination of antilymphocyte immunoglobulin (ALG) and methylprednisolone (MP) occurred in patients with hepatic failure (groups II and III) than those without hepatic failure (30% versus 6.3%; P = 0.043). However, there was no significant difference in the incidence of MP use alone (20% versus 25%; P = 0.746). Mortality rates for groups I, II, and III were significantly different (12.5%, 40%, 100%; P = 0.008). One patient in group I died of sepsis without evidence of HBV DNA, even in the terminal event. In group II, 3 of 5 patients (60%) were rescued by lamivudine therapy. In group III, without lamivudine treatment, there was a 100% mortality rate despite intensive plasmapheresis. HBV DNA was not detectable after lamivudine treatment in 7 of 8 patients in group I and 3 of 5 patients in group II. Creatinine levels did not change significantly during lamivudine treatment. Hepatitis B surface antigen and hepatitis B e antigen seroconversion rates after lamivudine treatment were 7.7% and 37.5%, respectively. We conclude that ALG is a potent trigger of HBV-related fulminant hepatic failure in renal transplant recipients, whereas lamivudine is an effective and lifesaving treatment. Prompt use of lamivudine is recommended in renal transplant recipients with evidence of HBV reactivation to prevent catastrophic fulminant hepatic failure.

Outcome of renal transplantation in hepatitis B surface antigen-positive patients after introduction of lamivudine

BACKGROUND

In end-stage renal disease patients with hepatitis B surface antigen (HBsAg), the risk of hepatic dysfunction after immunosuppression represents a large barrier in renal transplantation. Lamivudine is a potent inhibitor of hepatitis B virus (HBV) replication. We retrospectively investigated the outcome of HBsAg-positive renal transplantation recipients after lamivudine had become available.

METHODS

From July 1994 to August 2000, seventeen HBsAg-positive patients (M:F=15:2) received renal allografts (13:4=living:cadaveric donors). Liver function tests at the time of transplantation were normal in all patients. Pre-transplant liver biopsies performed in 15 patients demonstrated minimal inflammatory histology, except in three patients showing pathological and clinical signs of active hepatitis. Lamivudine was started pre-operatively in these three subjects. Another seven patients were treated with lamivudine for post-operative hepatic dysfunction. The remaining seven patients did not develop hepatic dysfunction after transplantation.

RESULTS

Lamivudine was initially effective in decreasing serum HBV DNA titres, and in normalizing hepatic enzymes. Lamivudine was well tolerated without significant side effects for 35.5+/-8.9 months after initiation of treatment. HBV DNA became negative in nine patients but remained positive in one patient. Among the nine patients with initial negative conversion of HBV DNA, two developed transient positive conversion of HBV DNA and two demonstrated persistent positive conversion. Among the patients with normal liver histology in the pre-transplant period, 41.6% (5/12) developed liver pathology progression after immunosuppression. All 17 patients had functioning grafts, except for one patient who developed relapsed IgA nephropathy.

CONCLUSIONS

Our data showed relatively favourable outcomes in hepatitis B-positive renal transplant recipients receiving lamivudine treatment, even though two patients developed lamivudine resistance.

Infections in recipients of kidney transplants

A review of infections in kidney transplant recipients is presented in this article, beginning with a discussion of the pretransplant infectious diseases evaluation and an overview of the timing of infectious posttransplant, and then focusing on individual types of infection.

Lamivudine treatment for hepatitis B reactivation in HBsAg carriers after organ transplantation: a 4-year experience

BACKGROUND

Reactivation of hepatitis B after organ transplantation in hepatitis B surface antigen (HBsAg) carriers may be fatal. In this study, we reported our experience of lamivudine treatment in HBsAg carriers who had post-transplant reactivation of hepatitis B.

METHODS

The patients were 15 men and one woman. Nine received kidney transplants, six received heart transplants, and one received a lung transplant. They developed a reactivation of hepatitis B 1-101 months (median, 14 months) after transplantation. They received lamivudine 100 mg daily on a compassionate-use basis, and had regular follow ups. The median pretreatment total serum bilirubin level was 3.0 mg/dL, and the alanine aminotransferase level was 357 U/L. Four of the 16 patients were positive for HBeAg. The serum hepatitis B virus (HBV) DNA levels were > 3000 pg/mL in 13 (81%) patients. Three were coinfected with hepatitis C virus.

RESULTS

The overall survival rate was 75%. All four fatal cases had a pretreatment total serum bilirubin level of > or = 3 mg/dL. Serum HBV-DNA soon became undetectable in 12 survivors. Of the 12 survivors, after a median treatment period of 101 weeks, a lamivudine-resistant strain with variation in the YMDD motif of the HBV polymerase gene developed in three (25%). None had significant adverse reactions to lamivudine treatment.

CONCLUSIONS

These results indicated that lamivudine is effective in the treatment of post-transplant hepatitis B reactivation, including patients with dual chronic hepatitis B and C. Early recognition of HBV reactivation and prompt lamivudine treatment are important to prevent mortality.

Current treatment strategies for chronic hepatitis B and C

For chronic hepatitis B, treatment with a 4-month course of interferon alfa-2b can achieve hepatitis B e antigen seroconversion, normalization of aminotransferase levels, reduced hepatic inflammation, and possibly reduced progression to cirrhosis and improvement in survival in 20%-30% of patients. Similar results can be achieved with a 12-month course of lamivudine, with response rates increasing to 40%-65% after 3 years of therapy. Interferon can also be used in early cirrhotic patients, and lamivudine can be used in advanced cirrhotics and immunosuppressed patients. Combination interferon and lamivudine therapy does not confer additional benefits. For chronic hepatitis C, the combination of interferon alfa-2b and ribavirin is the treatment of choice, offering superior sustained response rates (40%) compared with interferon alone (15%). Therapy should be administered for 12 months to patients with genotype 1 virus but for only 6 months to patients with genotypes 2 and 3. Patients experiencing relapse after 6 months of interferon monotherapy can be re-treated with interferon and ribavirin or high-dose interferon, with 45%-56% sustained response rates. However, relatively few patients who are prior nonresponders to interferon monotherapy will have sustained response to further interferon-based treatments, including combination therapy with ribavirin. Successful therapy not only leads to the eradication of viral RNA but also may delay progression to cirrhosis and hepatocellular carcinoma. Interferon combined with polyethylene glycol (PEG), shows promise as an improved formulation of interferon with yet higher sustained response rates.

Lamivudine and glycyrrhizin for treatment of chemotherapy-induced hepatitis B virus (HBV) hepatitis in a chronic HBV carrier with non-Hodgkin lymphoma

We report a chronic hepatitis B virus (HBV) carrier with non-Hodgkin lymphoma (NHL) who developed HBV hepatitis following conventional dose chemotherapy and was successfully treated with lamivudine and glycyrrhizin. A 55 year-old male patient with primary testicular NHL (diffuse large B-cell type) relapsed. During the salvage chemotherapy, the patient showed elevated serum levels of transaminase and HBV-DNA due to HBV reactivation. Treatment with lamivudine, an antiviral nucleoside analog, was started at a dose of 100mg/day. Shortly after the treatment the HBV-DNA level was suppressed, and sustained elevation of transaminase levels were normalized after additional treatment with glycyrrhizin. This experience suggests that lamivudine combined with glycyrrhizin may be effective for controlling HBV replication and treating chemotherapy-induced HBV hepatitis in chronic HBV carriers with NHL.

Recommendations for the outpatient surveillance of renal transplant recipients. American Society of Transplantation

Many complications after renal transplantation can be prevented if they are detected early. Guidelines have been developed for the prevention of diseases in the general population, but there are no comprehensive guidelines for the prevention of diseases and complications after renal transplantation. Therefore, the Clinical Practice Guidelines Committee of the American Society of Transplantation developed these guidelines to help physicians and other health care workers provide optimal care for renal transplant recipients. The guidelines are also intended to indirectly help patients receive the access to care that they need to ensure long-term allograft survival, by attempting to systematically define what that care encompasses. The guidelines are applicable to all adult and pediatric renal transplant recipients, and they cover the outpatient screening for and prevention of diseases and complications that commonly occur after renal transplantation. They do not cover the diagnosis and treatment of diseases and complications after they become manifest, and they do not cover the pretransplant evaluation of renal transplant candidates. The guidelines are comprehensive, but they do not pretend to cover every aspect of care. As much as possible, the guidelines are evidence-based, and each recommendation has been given a subjective grade to indicate the strength of evidence that supports the recommendation. It is hoped that these guidelines will provide a framework for additional discussion and research that will improve the care of renal transplant recipients.

Results on preemptive or prophylactic treatment of lamivudine in HBsAg (+) renal allograft recipients: comparison with salvage treatment after hepatic dysfunction with HBV recurrence

BACKGROUND

Lamivudine has been reported to be able to stabilize liver enzyme and hepatitis B virus (HBV) replication with recurrent hepatitis that has been regarded as a frequent and major risk factor for hepatic dysfunction and chronic liver disease in renal transplant recipients. Because large number of hepatitis antigenemia patients among renal transplant patients experience recurrent hepatic dysfunction with HBV recurrence and permanent histological deterioration, preemptive or primary prophylactic use of lamivudine before transplantation may be more beneficial than a trial for the treatment of advanced hepatic dysfunction.

METHODS

We conducted a double arm study to compare the efficacy of lamivudine between the preemptive (HBV DNA positive) or prophylactic (HBV DNA negative) trial for the maintenance of stable liver function (n=10) and the trial for the salvage of advanced hepatic dysfunction developed after renal transplantation (n=6) in hepatitis B viremia carrier renal transplant recipients.

RESULTS

Hepatic dysfunction with recurrent HBV antigenemia developed in 11 of 36 (30.6%) hepatitis antigenemia patients with a mean duration of 8.4 months (range 5-19.4 months). In six patients treated with lamivudine after hepatic dysfunction from recurrent hepatitis B viremia, serum AST and ALT level normalized within 1 month and HBV-DNA disappeared in all cases. HBV-DNA, however, reappeared in three (50%) without any discontinuation of lamivudine. Liver biopsy revealed recurrent chronic active hepatitis with severe activity of fibrosis in four cases, cholestatic fibrosing hepatitis in one, and permanent cirrhotic change in one. In seven patients who had preemptive lamivudine treatment at 9, 6, 2, 2, 1, 0, 0 month before the transplantation, HBV-DNA had converted to negative with a mean follow up of 1.2 months (range 1-2 month) in all case. Three patients who had prophylactic trials with lamivudine have all remained HBV-DNA negative. The recurrence rate of HBV viremia in the preemptive or prophylactic lamivudine treated group is 10.0% (1/10), which is significantly lower than that (42.3%, 11/25) in the nonlamivudine-treated group. The re-recurrence rate of HBV viremia was significantly higher (3/6, 50.0%) in the reactive lamivudine treated group than in prophylactic or preemptive group (1/10, 10%).

CONCLUSION

Although lamivudine treatment after hepatic dysfunction can be a sound conventional treatment modality, this preliminary study may suggest that preemptive or prophylactic trial of lamivudine before hepatic dysfunction might be a more effective strategy for prevention of permanent histological deterioration and recurrence of hepatitis B viremia.

Hepatitis B in transplantation

Hepatitis B has been a major challenge within the field of transplantation over the past few decades. Due to aggressive recurrence post-transplant, patients with hepatitis B have been excluded from the benefits of both solid organ and bone marrow transplants. Progress has been made, however, through an improved understanding of the biology of hepatitis B and the development of new antiviral strategies that can reliably suppress the virus. Patients with hepatitis B are now candidates for transplantation in an increasing number of circumstances. Careful pre-transplant evaluation is mandatory, together with a tailored antiviral regimen depending on the replicative status of the virus and the organ being transplanted. Minimizing steroid dose following transplantation is an important part of the strategy to reduce the risk of viral reactivation. Lamivudine has been an important development and it has assumed an increasing role in the management of these patients. As additional antivirals are developed, increasingly effective drug combinations will prevent viral recurrence as well as the emergence of drug-resistant mutants, which plagues the use of single agents. It is a rapidly evolving field and there is every reason for continued optimism.

An open-label study of lamivudine for chronic hepatitis B in six patients with chronic renal failure before and after kidney transplantation

OBJECTIVE

The course of hepatitis B virus (HBV) infection after kidney transplantation is aggressive, with a high mortality rate from liver disease mainly in patients who were serum hepatitis B e antigen (HBeAg) or HBV DNA-positive before transplantation. Lamivudine has been shown to be a potent inhibitor of HBV replication. The aim of the study was to examine the efficacy and safety of lamivudine therapy in patients with chronic renal failure and chronic HBV infection.

METHODS

The study population consisted of six potential candidates for kidney or combined kidney and liver transplantation aged 25-49 yr (four patients had already undergone a kidney transplantation and developed chronic rejection). All were serum HBeAg and/or HBV DNA-positive and had been maintained on hemodialysis for 3 months to 3 yr. The duration of HBV infection was 7 months to 14 yr. Serum alanine aminotransferase (ALT) levels ranged from 72 to 610 U/L (median, 158 U/L). Liver histological evaluation showed mild to moderate chronic hepatitis (n = 4) or liver cirrhosis (n = 2). None of the patients was infected with hepatitis C or D viruses. In four patients, treatment consisted of 10 mg of oral lamivudine per day. In the other two patients, a virological and biochemical response could be achieved only when the dose was increased to 40 mg/day.

RESULTS

Lamivudine treatment was associated with 1) normalization of serum ALT levels and rapid disappearance of serum HBV DNA (by hybridization) (five patients, one of whom died from sepsis); 2) seroconversion: disappearance of HBeAg (three patients) and HBsAg (two patients); 3) minor side effects: abdominal pain and nausea (one patient); 4) clinically asymptomatic lamivudine resistance 8 months after treatment (one patient); and 5) successful combined kidney and liver transplantation with no evidence of recurrent HBV infection at 6-8 months postoperatively (two patients with cirrhosis).

CONCLUSIONS

Lamivudine therapy is effective as an HBV replication inhibitor in patients with chronic renal failure and HBV infection. Prospective studies of lamivudine pharmacokinetics and dosing in renal failure are needed to be able to treat patients appropriately. Although our study is small and further follow-up is needed, our data suggest that lamivudine therapy may enable selected patients with chronic hepatitis B to undergo kidney or combined kidney and liver transplantation in patients with established cirrhosis.

Twelve months of lamivudine treatment for chronic hepatitis B virus infection in renal transplant recipients

BACKGROUND

Chronic hepatitis B virus (HBV) infection increases morbidity and mortality in renal transplant recipients (RTR). Lamivudine has shown promising results in patients with chronic hepatitis B, but experience with its use in RTR is limited.

METHODS

In a prospective, open labeled, uncontrolled trial, 19 HBsAg(+) RTR were treated with lamivudine for 12 months. HBV-serologic analysis, HBV-DNA quantitation, and HBV genome sequence analysis were performed every 3 months.

RESULTS

At baseline 16 patients were HBV DNA(+), 12 patients were HBeAg(+)/Ab (-). After 3 months HBV DNA was negative in 80% of patients. In the 3 patients with elevated liver enzymes, normal values were achieved within 12 weeks. At 12 months 4 of 8 HBeAg(+)/Ab(-) patients on treatment showed HBeAb, two of them with loss of HBeAg. Three patients developed mutations of the HBV polymerase gene associated with lamivudine resistance.

CONCLUSIONS

Lamivudine is safe and effective in HB-sAg(+) RTR, the rate of HBe-seroconversion and of lamivudine-resistance is comparable to that of nonimmunosuppressed patients.

Lamivudine for hepatitis B in liver transplantation: a single-center experience

BACKGROUND

Liver transplantation for hepatitis B virus (HBV) has been associated with a high rate of reinfection and graft failure. Lamivudine, a potent inhibitor of HBV replication, has been shown to prevent viral recurrence after transplantation.

METHODS

The effectiveness of lamivudine monotherapy for the management of HBV recurrence after liver transplantation was assessed. Lamivudine was used in three patient groups: (1) patients started before transplantation and continued after transplantation (n = 13); (2) patients treated after transplantation (n = 15); and (3) patients with de novo hepatitis B after transplantation (n = 4).

RESULTS

Median follow-up on lamivudine was 24 months. Active viral replication (HBV-DNA+) was seen in 17 (53%) of 32 at treatment initiation. All lost HBV-DNA at a mean of 2.4+/-1.6 months after lamivudine initiation. Twenty-six (81%) patients remain free of viral recurrence. Six (19%) patients have evidence of breakthrough infection with the YMDD mutant of HBV, two of whom progressed to graft failure. All four patients in group 1 who developed breakthrough had evidence of hepatitis B surface antigen expression in the explanted liver by immunohistochemistry despite being serum HBV-DNA negative before transplantation. No difference was observed among the three groups in DNA clearance or breakthrough rates.

CONCLUSIONS

Lamivudine achieves viral DNA clearance in almost all patients. Expression of viral antigens in the liver seems to identify patients at risk of developing HBV-DNA recurrence. Disease-free survival of 81% at 22 months is similar to data with hepatitis B immunoglobulin therapy. Given the safe clinical profile and high efficacy in the prevention of disease recurrence, lamivudine will favorably change the outlook of liver transplantation for HBV.

Hepatitis B

The management of acute HBV infection is supportive. Specific treatment is not indicated for HBV carriers because they often have no evidence of liver injury, and, further, do not respond to currently available therapies. Interferon monotherapy is best indicated for patients with chronic replicating HBV infection and evidence of chronic hepatitis. There is an increased likelihood of clearing HBsAg with interferon monotherapy as compared to lamivudine. Lamivudine is an oral nucleoside analog that is better tolerated than interferon. The clinical situations for its use are far more than interferon monotherapy. Lamivudine should be used in patients with decompensated cirrhosis and also in transplantation, both before and after transplantation. The post-transplant use of hepatitis B immune globulin (HBIG) and lamivudine combination therapy may be better for recipients who are identified in a replicative phase prior to transplantation. Hepatitis B coinfection with one or more viruses, HCV, HDV, or HIV, may occur. Both interferon and lamivudine have been useful in these patients. However, the data are sparse and heterogeneous. Therapy with one or both drugs will have to be tailored to the clinical situation. Combination therapy with immunomodulatory and/or antiviral drugs are what we will be looking toward in the future.

Lamivudine therapy for hepatitis B infection

BACKGROUND

Several new antiviral agents have recently been developed which can inhibit hepatitis B replication by at least two logs. Lamivudine is the most widely studied of these new agents. Extensive phase II and III studies in patients with chronic hepatitis B are in progress, or have been completed. The sustained HBeAg seroconversion rate in patients who have received 100 mg lamivudine rate increase from 17% at year one to 27% after 2 years. Early treatment results have suggested that lamivudine improves hepatic histology in patients with chronic hepatitis B, and can prevent recurrence of hepatitis B after liver transplantation. It is likely that in the absence of immune clearance to accelerate elimination of infected hepatocytes, inhibitors of virus replication such as lamivudine will need to be administered for a long period to substantially reduce the burden of infected hepatocytes in the liver, and prevent relapse. Histological improvement has been noted in between 38% and 52% of lamivudine-treated patients, exceeding the improvement seen in placebo recipients. Lamivudine has also been assessed in anti-HBe positive, HBV DNA positive patients. Preliminary results show that 65% of lamivudine recipients become HBV DNA negative and have normal serum aminotransferases after a year of treatment. The drug is generally well tolerated with few direct adverse events. Genotypic mutations have been observed in 11% after 1 year of treatment, but this percentage doubles after 2 years of therapy. Loss of susceptibility lamivudine has been found to be due to reverse transcriptase amino acid substitutions. Lamivudine is likely to be reserved for patients with replicative hepatitis B infection with active chronic hepatitis, and/or active cirrhosis. Both HBeAg and anti-HBe positive patients are benefited, as may be patients with cirrhosis.

Natural and iatrogenic variation in hepatitis B virus

The existence of HBV as quasispecies is thought to be favoured by the infidelity of HBV RT, which would account for the emergence of the many natural mutants with point substitutions. RT infidelity may also underlie the hypermutation phenomenon. Indeed, the oft-reported point mutation in the preC gene that leads to failure of HBeAg synthesis may be driven by a hypermutation-related mechanism. The presence of mutants with deletions and insertions involving single nucleotides and oligonucleotides at specific positions in the genome, and of mutants with deletions of even longer stretches particularly in the C gene, suggests that other mutagenic mechanisms operate. Candidates include slippage during mispairing between template and progeny DNA strand, the action of cellular topoisomerase I, and gene splicing using alternative donor and acceptor sites. Natural substitutions, deletions or insertions involving the Cp/ENII locus in the X gene can significantly alter the extent of viral replicative activity. Similar mutations occurring at other locations of Cp/ENII, and at B-cell epitope sites of the S gene are associated with failure to detect serological markers of HBV infection. HBV variation can also arise from recombination between coinfecting strains. S gene mutations that become evident following HBIG administration and HBV vaccination are all point substitutions, as are mutations in functional RT domains of the P gene after treatment with viral RT-inhibitory drugs. Widespread and long-term use of prophylactic and therapeutic agents may potentially generate serologically occult HBV variants that might become difficult to eradicate.

Lamivudine. A review of its therapeutic potential in chronic hepatitis B

Lamivudine is a deoxycytidine analogue that is active against hepatitis B virus (HBV). In patients with chronic hepatitis B, lamivudine profoundly suppresses HBV replication. Clinically significant improvements in liver histology and biochemical parameters were obtained with lamivudine in double-blind, randomised, trials in hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B and compensated liver disease. After 52 weeks of treatment, relative to placebo (< or = 25%), significantly more Chinese (56%) or Western patients (52%) treated with lamivudine 100 mg/day had reductions of > or = 2 or more points in Knodell necro-inflammatory scores. Moreover, significantly fewer lamivudine 100 mg/day than placebo recipients had progressive fibrosis in liver biopsies (< or = 5 vs > or = 15%) and fewer lamivudine- than placebo-treated patients progressed to cirrhosis (1.8 vs 7.1%). More lamivudine 100 mg/day than placebo recipients acquired antibodies to HBeAg after 52 weeks (16 vs 4% in Chinese patients and 17 vs 6% in Western patients). ALT levels normalised in significantly more lamivudine than placebo recipients enrolled in these trials. In HBeAg-negative, HBV DNA positive patients with compensated liver disease enrolled in a double-blind, randomised study, HBV DNA levels were suppressed to below the limit of detection (< 2.5 pg/ml) and ALT levels normalised in 63% and 6% of patients treated with lamivudine 100 mg/day or placebo for 24 weeks. Clinically significant improvements in liver histology were obtained in 60% of patients treated with lamivudine for 52 weeks in this study. Lamivudine 100 mg/day for 52 weeks produced similar or significantly greater improvements in liver histology and ALT levels than 24 weeks' treatment with lamivudine plus interferon-alpha. In liver transplant candidates with chronic hepatitis B and end-stage liver disease, lamivudine 100 mg/day alone, or in combination with hepatitis B immune globulin, generally suppressed HBV replication and appeared to protect the grafted liver from reinfection. Lamivudine 100 mg/day suppressed viral replication and improved liver histology in liver transplant recipients with recurrent or de novo chronic hepatitis B. Lamivudine 300 or 600 mg/day reduced HBV replication in HIV-positive patients. The incidence of adverse events in patients with chronic hepatitis B and compensated liver disease treated with lamivudine 100 mg/day or placebo for 52 to 68 weeks was similar. 3.1- to 10-fold increases in ALT over baseline occurred in 13% of patients during treatment with lamivudine 100 mg/day or placebo for 52 weeks. Post-treatment ALT elevations were more common in lamivudine than placebo recipients; however, these generally resolved spontaneously; < or = 1.5% of lamivudine- or placebo-treated patients experienced hepatic decompensation.

CONCLUSION

Lamivudine inhibits HBV replication, reduces hepatic necro-inflammatory activity and the progression of fibrosis in patients with chronic hepatitis B, ongoing viral replication and compensated liver disease including HBeAg-negative patients. The drug also suppresses viral replication in liver transplant recipients and HIV-positive patients. Thus, lamivudine is potentially useful in a wide range of patients with chronic hepatitis B and ongoing viral replication.

Advances in antiviral therapy

Multiple agents for the treatment and prevention of viral illnesses have been developed during the past few years. While in many cases this has been in direct response to the human immunodeficiency virus type 1 epidemic, a number of new antiviral agents are relevant to the practice of general pediatrics. This article reviews recent advances in the therapy of some common and a few unusual viral illnesses of children. The indication and efficacy of the newly developed agents valacyclovir, famciclovir, cidofovir, oral and intraocular ganciclovir, adefovir, respiratory syncytial virus immune globulin, palivizumab, and imiquimod are discussed, as well new uses of acyclovir, lamivudine, and ribavirin. Many of the antivirals discussed, including valacyclovir and cidofovir, have not yet been studied in children, but they hold promise for improving the treatment of pediatric viral infections.

Lamivudine therapy for chemotherapy-induced reactivation of hepatitis B virus infection

A 54-yr-old man with lymphoma and serological evidence of prior hepatitis B virus (HBV) infection, with detectable anti-HBc and anti-HBs, was treated with intensive chemotherapy. He had reactivation of HBV infection with acute hepatitis B manifest by detectable HBsAg and elevated aminotransferase levels >1000 IU/L. He was treated with lamivudine 150 mg daily and had prompt resolution of acute hepatitis B with return of elevated aminotransferases to normal, and initial loss of HBeAg with later loss of HBsAg. Lamivudine was continued during the course of further chemotherapy as prophylaxis against repeat HBV reactivation. Lamivudine is a nucleoside analogue that is a potent inhibitor of HBV reverse transcriptase and HBV replication. Lamivudine therapy should be considered for the treatment of HBV reactivation and might play a future role as preemptive therapy of HBV reactivation in patients with prior hepatitis B or chronic hepatitis B with inactive viral replication.

Treatment of chronic hepatitis B with lamivudine in renal transplant recipients

BACKGROUND

Lamivudine is a potent inhibitor of hepatitis B virus replication. Little has been reported about the efficacy and safety of lamivudine in the treatment of chronic hepatitis B in the setting of renal transplantation.

METHODS

Two patients were treated for chronic hepatitis B with lamivudine and subsequently underwent renal transplantation. Four other patients were treated with lamivudine for reactivation of hepatitis B after renal transplantation. Chronic hepatitis B was proven histologically in all the patients. The doses of lamivudine ranged from 100 to 150 mg/day. Hepatic enzyme and viral markers were monitored.

RESULTS

Lamivudine was well tolerated for a median duration of 8 months (range, 4-14 months) without significant side effects. Viral replication was suppressed, as evidenced by negative conversion of serum hepatitis B virus DNA in all the patients. Hepatic enzyme was also normalized. Modification of doses of immunosuppressant regimen was not required in using lamivudine in all patients. One patient experienced acute rejection and responded to solumedrol pulse therapy with normalization of graft function. Normal graft function was maintained in other patients while they were treated with lamivudine.

CONCLUSION

Lamivudine was a safe and effective therapy for activated hepatitis B in renal transplant recipients in the short term.

Lamivudine treatment of chronic hepatitis B

Several new nucleoside analogues have been developed which can inhibit hepatitis B replication by at least two logs. Lamivudine is the most widely studied of these new agents. Extensive phase II and III studies in patients with chronic hepatitis B have been completed. The sustained HBeAg seroconversion rate in patients who have received 100 mg lamivudine increases from 17% after a year of treatment to 27% after 2 years of treatment. Histological improvement has been noted in 38%-52% of lamivudine-treated patients, exceeding the improvement seen in placebo recipients. Similar histological improvement has been noted in anti-HBe-positive, DNA- positive patients. Lamivudine can prevent recurrence of hepatitis B after liver transplantation. It is likely that in the absence of immune clearance to accelerate elimination of infected hepatocytes, inhibitors of virus replication such as lamivudine will need to be administered for a long period to reduce the burden of infected hepatocytes in the liver, and to prevent relapse. The drug is generally well tolerated with few direct adverse events. Genotypic mutations have been observed in 23% (range 13-32%). In a study in Asian patients treated for two years the incidence of these mutants increased to 38% (as detected by PCR). Loss of susceptibility to lamivudine has been found to be due to reverse transcriptase amino acid substitutions. Lamivudine is likely to be reserved for patients with replicative hepatitis B infection with active chronic hepatitis, and/or active cirrhosis. Copyright 1998 John Wiley & Sons, Ltd.