Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The woodchuck hepatitis virus (WHV) and its natural host, the Eastern woodchuck (Marmota monax), have been established as a model of hepatitis B virus (HBV)-induced disease. Several published studies have used this experimental animal model system to demonstrate potential antiviral therapies for chronic HBV infections. However, there has been little comparative information available on compounds used in clinical anti-HBV studies in WHV-infected woodchucks, thereby making interpretations of the potential relative effectiveness of new antiviral agents in humans more difficult. In this report, using a series of placebo-controlled studies, we compared the relative effectiveness of several nucleoside analogues that have been used in clinical trials for the treatment of chronic HBV infection against WHV replication in chronically infected woodchucks. Adenine-5'-arabinoside monophosphate (Ara-AMP [vidarabine]), ribavirin, (-)beta-L-2',3'-dideoxy-3'-thiacytidine (3TC [lamivudine]), and famciclovir (oral prodrug of penciclovir) induced depressions in viremia and intrahepatic WHV-DNA replication that were consistent with their relative effectiveness in anti-HBV human clinical trials. As observed in HBV-infected patients, 3' azido-3'-deoxythymidine (AZT [zidovudine]) had no effect on WHV replication in these studies. These experimental results more firmly establish chronic WHV infection in woodchucks as an accurate and predictive model for antiviral therapies against chronic HBV infection in humans and provide a baseline for comparative antiviral effects of other experimental antiviral agents in the WHV/woodchuck model system.
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PMID:Treatment of chronic woodchuck hepatitis virus infection in the Eastern woodchuck (Marmota monax) with nucleoside analogues is predictive of therapy for chronic hepatitis B virus infection in humans. 1079 94

The prevention of recurrent hepatitis B virus (HBV) infection after orthotopic liver transplantation (OLT) with hepatitis B immunoglobulin (HBIG) is expensive and requires indefinite parenteral administration. Lamivudine is a nucleoside analogue capable of inhibiting HBV replication. The aim of this study is to determine the efficacy of lamivudine in the prevention of recurrent HBV infection after a course of HBIG in patients who were hepatitis B surface antigen (HBsAg) positive and hepatitis Be antigen (HBeAg) negative before OLT. Patients at high risk for recurrent HBV infection (HBeAg positive and HBV DNA positive) were excluded. Thirty HBsAg-positive, HBeAg-negative patients underwent OLT from January 1993 to June 1997. All 30 patients were administered HBIG after OLT and, after 2 years, were given the option of continuing with HBIG or switching to lamivudine. Five patients were excluded: 3 patients were lost to follow-up and 2 patients died of technical complications. Three patients terminated HBIG therapy at 8, 24, and 29 months after OLT, and reinfection with HBV occurred in 1 patient. Six patients elected to continue HBIG therapy for life; 1 patient died of melanoma and the remaining 5 patients are HBsAg negative, with an average follow-up of 73 months. Sixteen patients were converted to lamivudine after a course of HBIG, and all 16 patients are HBsAg negative, with an average follow-up of 51 months after OLT. Five patients have been on lamivudine monotherapy for more than 24 months. These results suggest that lamivudine administered after a posttransplantation course of HBIG can effectively prevent the recurrence of HBV infection in patients who are HBsAg positive and HBeAg negative before OLT.
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PMID:Lamivudine after hepatitis B immune globulin is effective in preventing hepatitis B recurrence after liver transplantation. 1091 64

We evaluated the safety and efficacy of long-term lamivudine monotherapy in a group of 25 patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B. Lamivudine was administered in a daily dose of 150 mg for a mean of 26 +/- 7 months and was well tolerated. No patient lost hepatitis B surface antigen (HBsAg). The rate of initial biochemical response increased from 88% at 6 months to 96% at 12 months of therapy, but it progressively decreased thereafter; the biochemical remission rate was 68% at 18 months, 59. 5% at 24 months, and 42.5% at >/=30 months. Alanine transaminase (ALT) increased to higher than the baseline levels in 8 of the 11 patients with a biochemical breakthrough reaching acute hepatitis levels in 6 of them. Acute icteric hepatitis developed in one patient. The virologic remission rate assessed by a sensitive quantitative polymerase chain reaction (PCR) assay was 68% at both 6 and 12 months, decreasing thereafter to 52% at 18 months and to 41. 6% at both 24 and >/=30 months. Virologic breakthroughs were always persistent and preceded ALT elevations by a median of 4 (3-24) months. YMDD mutants were detected in all patients with a virologic breakthrough. In conclusion, in patients with HBeAg-negative chronic hepatitis B, long-term lamivudine therapy is safe and is associated with high biochemical and virologic response rates at the end of the first year. However, response rates tend to decrease with time and breakthroughs due to YMDD mutants accumulate. ALT activity during breakthroughs often exceeds the baseline and may reach even acute hepatitis levels.
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PMID:Efficacy of long-term lamivudine monotherapy in patients with hepatitis B e antigen-negative chronic hepatitis B. 1100 33

Currently seven viruses, A, B, C, D, E, G and transfusion transmitted virus (TTV), are recognised in the hepatitis virus alphabet. Hepatitis G virus and TTV probably do not cause liver disease in humans. Hepatitis A and E usually cause a self-limiting hepatitis followed by complete recovery but occasionally cause fulminant hepatic failure. Hepatitis B and C are major public health problems worldwide due to their sequelae of chronic hepatitis, cirrhosis and primary liver cancer. Chronic hepatitis C is a particular health issue for Western Europe already, accounting for 40% of end-stage cirrhosis and 30% of liver transplants. The contribution of hepatitis C to chronic liver disease is predicted to rise in the future. Vaccines can prevent hepatitis A and B. Interferon alpha is effective treatment in 25-30% of patients with chronic hepatitis B or C. The prospects for treating chronic hepatitis B have been improved by the introduction of reverse transcriptase inhibitors. Lamivudine is the first drug of this class to be licensed. The optimal use of these new drugs is currently being studied. The success rate for treating chronic hepatitis C can be raised to about 40% with combination therapy of interferon alpha and ribavirin. A large research effort to discover new antiviral agents against hepatitis C is already giving the prospect of more effective therapies in the next few years.
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PMID:Virus hepatitis update. 1119 85

Treatment of chronic hepatitis B is directed at interrupting the natural history and clinical outcomes of the disease. It needs to take into account the virology and replication cycle of the hepatitis B virus (HBV), and the host immune response to HBV. Long term follow-up of patients treated with interferon supports the paradigm that a sustained, major suppression of HBV replication, particularly that associated with hepatitis B e antigen (HBeAg) seroconversion, interrupts the natural history of hepatitis B. The availability of potent but well tolerated and orally available HBV antivirals, of which lamivudine is the prototype, has allowed clearer treatment objectives to be formulated. These are: temporary or permanent reduction of hepatitis (necroinflammatory) activity, arrest of fibrotic progression, prevention of cirrhosis and liver failure, and prevention of recurrent HBV infection after liver transplantation. Lamivudine has good medium term efficacy in achieving each of these objectives. The only significant problem for the longer term is emergence of antiviral resistance conferred by mutations in the YMDD (tyrosine-methionine-aspartic acid-aspartic acid) motif of the HBV reverse transcriptase. As a result, contentious issues remain about defining when antiviral therapy is indicated, whether to treat for a defined interval or indefinitely, and when to stop treatment if HBeAg seroconversion is not achieved. Some personal views are expressed in this review. Among newer HBV antivirals in clinical studies, adefovir dipivoxil, entecavir and emtricitabine appear to be at least as potent as lamivudine in suppressing HBV replication. Famciclovir appears less potent. In vitro studies show that YMDD mutations confer cross-resistance between lamivudine, emtricitabine and beta-L-Fd4C (L-2',3'-didehydro-dideoxy-5-fluorocytidine). However, adefovir dipivoxil, lobucavir, entecavir, DAPD (beta-D-2,6-diaminopurine dioxolane) and possibly clevudine (L-FMAU) suppress replication of YMDD mutant HBV, as well as wildtype. Preliminary studies indicate clinical efficacy of adefovir dipivoxil once resistance to lamivudine has developed. Immunomodulatory approaches to treatment of chronic hepatitis B are conceptually attractive, but newer agents used to date (thymalfasin, interleukin-12, therapeutic vaccines) have not demonstrated sufficient efficacy for widespread use. The next challenge for HBV treatment is to use antivirals in combination and/or in cyclical therapy to reduce the emergence of drug resistance and increase efficacy, particularly to achieve sustainable post-treatment suppression of hepatitis B.
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PMID:Clinical potential of emerging new agents in hepatitis B. 1108 96

Subacute hepatitis is a common and distinct clinicopathological entity due to Hepatitis B and E viruses in India. Lamivudine has been established as a safe and effective antiviral agent for the treatment of chronic HBV hepatitis. This drug was administered orally along with intravenous (I/V) Glycyrrhizin, an immunomodulator drug, in an open pilot trial to assess its efficacy in the treatment of subacute hepatitis. The results establish the safety and efficacy of Lamivudine in combination with I.V. Glycyrrhizin in subacute Hepatitis.
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PMID:Treatment of subacute hepatitis with Lamivudine and intravenous Glycyrrhizin: a pilot study. 1128 81

Hepatitis B virus (HBV) reactivation, a well-known complication in immunosuppressed patients, can give rise to acute hepatitis and even fatal fulminant hepatitis. Three Japanese males with non-Hodgkin's lymphoma (NHL) who were carriers of HBV received high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT). To prevent HBV reactivation, all received oral lamivudine (150 mg/day), a nucleoside analogue, at the start of chemotherapy. All were treated at full-dose intensity, including corticosteroids, without modification of treatment regimens. All three patients completed the total course of chemotherapy and PBSCT, with no signs of HBV reactivation. Peripheral blood stem cell (PBSC) harvests and hematological recoveries after transplantation were not affected by lamivudine, which was continued for at least 16 weeks after transplantation. HBV-DNA and DNA polymerase levels remained negative/normal after discontinuation of lamivudine. Lamivudine effectively inhibits HBV replication and has few serious adverse effects, particularly those related to hematopoiesis. Thus, prophylactic use of lamivudine from initiation of chemotherapy deserves consideration in the treatment of HBV carriers who require immunosuppressive chemotherapy, and may prevent HBV reactivation.
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PMID:A possible role for lamivudine as prophylaxis against hepatitis B reactivation in carriers of hepatitis B who undergo chemotherapy and autologous peripheral blood stem cell transplantation for non-Hodgkin's lymphoma. 1131 73

A case study is presented of a 28-year-old, HIV-infected male with hepatic dysfunction of unknown etiology. After failure on AZT and 3TC, the patient was prescribed d4T, 3TC, and nevirapine. After three weeks of treatment, the patient had poor appetite, bloating, and fever. Blood chemistries, diagnostic imaging, and hepatitis and CMV serologies were all performed, with no clear findings. Since there had been reports of liver dysfunction from nevirapine, all medications were ceased, and the patient's condition improved. The role of antiretroviral agents, particularly nevirapine, in liver dysfunction is explored. Contraindications in prescribing this drug, particularly for patients with impaired liver function or current alcohol or drug abuse, are also discussed.
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PMID:Hepatitis in an HIV-infected man. 1136 58

It is critical to take HIV medications, particularly protease inhibitors, exactly as prescribed to reduce the risks of developing resistance. The Food and Drug Administration (FDA) recently approved a new drug, Combivir, a combination of 3TC (lamivudine) and AZT in one tablet. Combivir works by interfering with the HIV life cycle to prevent it from replicating, and is taken twice a day with or without food. Patients with low body mass, hepatitis, or liver or kidney disease should not take Combivir. Blood counts need to be monitored regularly when taking this drug. Potential side effects include headache, nausea, fatigue, diarrhea, nasal congestion, or flu-like symptoms. A phone number is provided for more information on Combivir.
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PMID:What you need to know about Combivir. 1136 67

While it appears that protease inhibitors in combination therapies are saving lives, questions continue: (1) which combinations of protease inhibitors and other antiretroviral agents are most effective in restoring immune function, (2) how these combinations can be used most effectively, and (3) what is the best time to start using them? An evaluation is presented on the immunological value of specific drug cocktail combinations and a comparison of the best and worst drug combinations and the reasons for this assessment. It indicates that Norvir is the most effective of all four protease inhibitors in preventing opportunistic infections, lymphomas, and cancers. D4T and 3TC are the safest and most effective of the nucleosides for preventing or remitting opportunistic infections when used with protease inhibitors. Rescriptor is the most therapeutic of the two non-nucleoside reverse transcriptase inhibitors in increasing absorption of protease inhibitors. The best drug combination therapies are listed as follows: Norvir plus Rescriptor; Norvir plus D4T; Norvir plus 3TC; Norvir, Rescriptor, and D4T; Norvir, Rescriptor, and 3TC; Norvir, D4T, and 3TC; and Crixivan or Viracept plus Rescriptor plus either D4T or 3TC. The worst drug combination therapies are listed as follows: AZT plus ddI (used in combination with a protease inhibitor); AZT or ddI or Combivir (used in combinations with a protease inhibitor); and any two protease inhibitors used together in any person with active hepatitis or elevated liver enzymes or impaired kidney function.
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PMID:An evaluation of drug cocktail combinations for their immunological value in preventing/remitting opportunistic infections. 1136 16


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