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Lamivudine 150 mg for Hepatitis B

Lamivudine 150 mg for Hepatitis B

Hepatitis B is an infection of the liver caused by the hepatitis B virus (HBV). It can trigger both acute and chronic infection. The infection can be avoided through vaccination, and some of the long-term outcomes and complications from the infection can be limited through premature treatment. Antiviral therapy is currently the most generally used treatment for chronic hepatitis B. Lamivudine is among the antiviral agents that is currently used as a first-line therapy for those with chronic hepatitis B.

Lamivudine is an antiviral medication used to handle chronic hepatitis B. It is taken orally, once a day, and has been shown to cut down the volume of hepatitis B virus in the body. In patients with constant hepatitis B, lamivudine has been shown to decrease the quantity of virus in the liver, better liver harm, and lower the degree of a substance called hepatitis B e antigen. Lamivudine is used to manage the hepatitis B e antigen positive and negative patients who have active liver disease, or who may have had liver inflammation in the past, as demonstrated by abnormal blood tests and or liver biopsy. This medication has been FDA approved for treatment of chronic hepatitis B since 1998.

Mechanism of Action

Inhibition of Reverse Transcriptase

Lamivudine is a nucleoside analog. The drug inhibits the activity of reverse transcriptase, a viral chemical that is crucial for the hepatitis B and HIV viruses to replicate in the body. Reverse transcriptase is responsible for producing new viral genetic material. When the virus is able to replicate, it becomes much more difficult to fight with the body's immune system. However, by inhibiting the activity of reverse transcriptase, lamivudine is able to prevent the hepatitis B virus from multiplying, effectively preventing the worsening of the infection.

lamivudine 150 mg for hepatitis b

Suppression of Viral Replication

Following inhibition of reverse transcriptase, the viral DNA fails to be formed. Consequent to this, both the hepatitis B viral DNA and RNA gets degraded. It ultimately results in the depletion of viral particles in the patients. The duration after which the complete viral load is reduced is yet to be ascertained. However, the weekly observation of HBV DNA, HBsAg and HBeAg is seen as the parameter for the effective of the therapy.

Effectiveness Against Hepatitis B Virus

Lamivudine has been shown to be effective in the treatment of hepatitis B. Clinical trials suggest that after one year of treatment, approximately 50% of patients show signs of improvement, as indicated by loss of HBeAg, gain of Anti-HBe, and/or liver enzyme normalization. Patients who achieve this response generally show a significant improvement in their disease state. This means that some of the liver damage which has occurred may regress, and patients become less likely to develop complications of liver disease, such as liver cirrhosis and liver cancer.

Administration and Dosage

Recommended Dosage of Lamivudine

Adult patients and adolescents weighing at least 30kg the recommended oral dose of LAMIVIR is 150 mg, taken once dailyrocket-3Adult patients with hepatic insufficiency who have been prescribed LAMIVIR for hepatic insufficiency due to reduction in dosage should be prescribed the 100 Mg. dose oral LAMIVIR accordingly .Dosage adjustments should be made for null patients with creatinine inflection. Plasma concentrations of LAMIVIR are enlarged and the half-life is prolonged in renally impairedThe recommended dose of LAMIVUDINE in paediatric patients, aged at least 2 years is 3 mg per Kg, orally, once daily, to a upper limit of 100 Mg. per day. Admissible dosage form are available.

Monitoring and Adjusting Dosage

Available clinical guidelines on monitoring and adjusting dosage of lamivudine, support and advise that patients should have their liver function tests and HBV viral load checked as frequently as required. If the viral load is undetectable at 6 months a trial withdraw should be done. If the viral load is detectable at 12 months consider adding or switching to tenofovir. Considering the clinical guidelines, it indicates that at month 12 an increased possibility of viral resistance is expected. At month 12 treatment with lamivudine should be reviewed, if treatment with lamivudine is considered and patient is male, overweight, with intermediate or high HBV viral load and with family history of HCC, consider tenofovir and also at month 12 all patients with HBV STR, HBV liver screen and upper abdominal ultrasound should be carried out. Also measure baseline eGFR and at month 12, patients taking tenofovir and monitored for eGFR at least annually. Furthermore at month 12, patients taking tenofovir should have liver screen with all on monotherapy to have HBV STR, liver screen, eGFR and upper abdominal ultrasound and those with cirrhosis should be monitored with 6 monthly ultrasound. Additionally, at year 12 patients must have an upper abdominal and liver ultrasound every six months.

Bibliography

  1. Rouviere, C. P., Dousson, C. B., & Tavis, J. E. (2020). HBV replication inhibitors. Antiviral research. (https://www.sciencedirect.com/science/article/am/pii/S0166354220302291)

  2. Chauhan, R., Li, Q., Woodson, M. E., Gasonoo, M., Meyers, M. J., & Tavis, J. E. (2021). Efficient inhibition of hepatitis B virus (HBV) replication and cccDNA formation by HBV ribonuclease H inhibitors during infection. Antimicrobial Agents and Chemotherapy, 65(12), 10-1128. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8597750/)

  3. Qu, B. & Brown, R. J. P. (2021). Strategies to inhibit Hepatitis B Virus at the transcript level. Viruses. (https://www.mdpi.com/1999-4915/13/7/1327/pdf)

  4. Kammarabutr, J., Mahalapbutr, P., Okumura, H., Wolschann, P., & Rungrotmongkol, T. (2021). Structural dynamics and susceptibility of anti-HIV drugs against HBV reverse transcriptase. Journal of Biomolecular Structure and Dynamics, 39(7), 2502-2511. (https://www.tandfonline.com/doi/abs/10.1080/07391102.2020.1751715)

  5. Nimanong, S., Savetsila, C., & Tanwandee, T. (2020). Low Rate of Long-term Virological Suppression in Chronic Hepatitis B Patients Treated with Lamivudine. Journal of the Medical Association of Thailand, 103. (https://search.ebscohost.com/login.aspx?direct=true&profile=ehost&scope=site&authtype=crawler&jrnl=01252208&AN=147612210&h=LQcRsPqT%2FMJgxVQIM%2B5%2F%2F7%2FPXWAXO1ynBfhEiy92V96Mkx2fugdlS%2BRgVk%2BpxuBkq6o%2FJdWWDvSIwS5dJUt6oQ%3D%3D&crl=c)

  6. Jia, J., Shang, J., Tang, H., Jiang, J., Ning, Q., Dou, X., ... & EVOLVE Study Group. (2020). Long-term outcomes in Chinese patients with chronic hepatitis B receiving nucleoside/nucleotide analogue therapy in real-world clinical practice: 5-year results from the EVOLVE study. Antiviral Therapy, 25(6), 293-304. (https://journals.sagepub.com/doi/pdf/10.3851/IMP3372)

  7. Woo, H. Y., Park, J. Y., Bae, S. H., Kim, C. W., Jang, J. Y., Tak, W. Y., ... & Ahn, S. H. (2020). Entecavir+ tenofovir vs. lamivudine/telbivudine+ adefovir in chronic hepatitis B patients with prior suboptimal response. Clinical and Molecular Hepatology, 26(3), 352. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7364362/)