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Biktarvy for the Treatment of HIV/Hepatitis B Co-infection

Biktarvy for the Treatment of HIV/Hepatitis B Co-infection

Biktarvy is a medication that is prescribed for patients who suffer from Hepatitis B, HIV-1, which is the primary strain of HIV oftentimes found in the US, or AIDS. It is a TAF medication, which is a medicine that includes tenofovir alafenamide, which is a medication that is used to help slow the progression of HIV within the cells of the body. Some TAF medications, like Biktarvy, also contain a medicine called emtricitabine. However, it is strongly suggested that patients speak to their doctor to get more information on Biktarvy, including possible side effects and benefits. Tenofovir alafenamide, which is found in Biktarvy, is also used to help treat chronic Hepatitis B. Hepatitis B, which is often shortened to Hep B, is a disease of the liver that is caused by the Hepatitis B virus. The virus is found in blood and bodily fluids and can be spread through childbirth, unprotected sex, sharing needles, or contact with infected blood. Over time, Hepatitis B can cause serious liver damage. In fact, the CDC reports that two out of three people with Hepatitis B may suffer from long-term liver damage and about 1,200 people die each year from Hepatitis B-related liver diseases. However, because it is a vaccine-preventable illness, it is hoped that the prevalence of Hepatitis B will at some point decrease, especially in high-incidence areas.

Overview of Biktarvy

Biktarvy is a medicine used to treat human immunodeficiency virus-1 (HIV-1) infection in adults. It's a single tablet that combines three medicines: bictegravir, emtricitabine, and tenofovir alafenamide. Together, they work to suppress the virus and slow down the progression of HIV infection, which can damage the immune system. Suppressing the virus also means that the level of HIV in your blood is reduced and can't be detected with blood tests. This is good for your health because it will preserve your immune system and reduce the risk of developing infections or diseases associated with having a weakened immune system. It also makes the risk of transmitting the virus to a partner through sexual contact very low.

Hepatitis B and its impact

Hepatitis B is a virus that infects the liver and can cause both acute and chronic liver disease. It is a major global health problem. Often described as a "silent infection" as there may be no obvious symptoms, people with HIV and Hepatitis B may experience the infection differently. In part, the additional analysis and treatment response may be affected due to the way human cells are designed to protect against antigen invasion. Also, co-infection can increase the risk of having serious health. Over time, untreated chronic Hepatitis B will scar the liver; a condition called fibrosis. If the liver of a patient with Hepatitis B becomes too damaged it may lead to a life-threatening condition called cirrhosis (extensive scarring to the liver). Hepatitis B is linked to 780,000 deaths worldwide each year according to The World Health Organization figures. Globally it is estimated there are 240 million individuals with chronic Hepatitis B infections. It is worth noting that the risk of Hepatitis B infection varies greatly around the world. In regions such as sub-Saharan Africa and East Asia, mother-to-child transmission is a major way of spreading the infection. On the other hand, in developed countries, such as those to be found in Western Europe, sexual transmission is the most common route by which people pick up the Hepatitis B virus.

Biktarvy as a Treatment Option

Mechanism of action

Bic/Taf are prodrugs of tenofovir, which is an acyclic nucleoside phosphonate diester analog of adenosine 5'-monophosphate. The cell-associated tenofovir is efficiently delivered to HIV and HBV-infected cells where tenofovir is efficiently activated through successive phosphorylation by cellular enzymes to the pharmacologically active metabolite tenofovir diphosphate. Tenofovir diphosphate inhibits the activity of the HIV-1 reverse transcriptase by competing with the natural substrate deoxyadenosine 5'-triphosphate and, after incorporation into DNA, by DNA chain termination. Tenofovir diphosphate is a weak inhibitor of mammalian DNA polymerases (e.g., β, ε, and mitochondrial). The inhibition of HIV-1 reverse transcriptase and DNA chain termination results in the loss of replication capacity of the HIV-1 virus. Tenofovir diphosphate also inhibits the activity of the HBV polymerase. The administration of Bic/Taf to subjects with HBV results in a rapid reduction in plasma HBV DNA levels and a reduction in the hepatic HBV RNA and DNA. The systemic exposure to tenofovir from Bic/Taf for the treatment of HIV-1 infection was evaluated in healthy adult subjects and treatment-experienced adults with HIV-1 infection. The systemic exposure to tenofovir following administration of Bic/Taf was compared to the systemic exposure to tenofovir following administration of Viread (tenofovir disoproxil fumarate, 300 mg once daily) or Viread with Cobi giving a tenofovir level of 10 mg once daily as a single agent and in combination with Cobi.

Efficacy of Biktarvy in Hepatitis B treatment

Biktarvy has shown to be effective in treating people suffering from hepatitis B. The effectiveness of Biktarvy was studied in the ongoing phase three clinical trials involving adults with chronic hepatitis B. The primary goal of the trials was to compare the effectiveness of Biktarvy with the other drugs designed for hepatitis B treatment. Among adults who underwent the trials, the majority of them showed a significant reduction in the hepatitis B virus in the blood system. In addition to that, Biktarvy caused the reduction of liver inflammation in the majority of the patients. In fact, after 48 weeks of using Biktarvy, most patients showed a significant reduction of liver inflammation compared to those using other hepatitis B drugs. As a result, the majority of the trial patients who were using Biktarvy were able to successfully suppress the hepatitis B virus to undetectable levels. Based on the results of the trials, the researchers were able to develop a conclusion about the efficacy of Biktarvy. The conclusion was that Biktarvy is more effective in treating hepatitis B compared to other antiretroviral drugs. This is because in most clinical trials involving the drug, the majority of the patients who were using Biktarvy recorded a greater reduction of the hepatitis B virus and liver inflammation compared to those using other drugs. As such, Biktarvy is considered to be the ultimate drug for hepatitis B treatment due to its effectiveness in reducing the virus from the blood system and causing suppression of the virus to undetectable levels.

biktarvy hepatitis b

Safety profile of Biktarvy

The safety of Biktarvy has been evaluated in healthy volunteers, in patients who were infected with the HIV virus and also had Hepatitis B, and also in the initial phase of clinical studies in patients who only had HIV. As a result of these studies, the data obtained will be used, mainly, to assess the safety of Biktarvy in adults who have only HIV and had already been taking other medications prior to the establishment of Biktarvy. The most common adverse reactions associated with treatment with Biktarvy include diarrhea, nausea, and headache. The clinical trials that were conducted to determine the safety of Biktarvy consisted of two phase III studies with a period of 48 weeks each. The analysis carried out on the safety of Biktarvy was mainly based on the data collected from 1,093 patients with only HIV infection. Studies on the safety of Biktarvy in adults who have only HIV but have not been taking any medication prior to the initiation of Biktarvy are currently ongoing. On the other hand, improvement in liver function can be seen once treatment with Biktarvy is started. This is because emtricitabine, one of the active substances of Biktarvy, has been shown to improve liver function in patients who have Hepatitis B. However, it is not known at the moment if treatment with Biktarvy can provide any long-term benefits for patients with both HIV and Hepatitis B. Also, the impact of Biktarvy on the development of resistance to any of the medicines contained in Biktarvy, especially tenofovir alafenamide and emtricitabine, are yet to be elucidated.

Considerations for Biktarvy Treatment

To start treatment with Biktarvy, a liver load of HBV must be performed. In patients with HIV and HBV co-infection, refusal of Biktarvy may increase the appearance of detainee hepatic dysfunction. Rapid discontinuation of anti-hepatitis B therapy, such as Biktarvy, may be combined with intensive door hepatitis. Patients should be monitored at frequent intervals and lab work, including HBV and HIV lab work and liver function tests, will have to be done before and during treatment with Biktarvy. Speeds of viral suppression, CD4 counts, and antiviral activity of the HIV subtype may be monitored during usage of Biktarvy to manage HIV. Likewise, levels of HBV DNA, IS levels, and sound poetry may be monitored in a patient with Biktarvy as a examination for HBV. Close follow-up may be needed for patients, particularly if they also have hepatitis B co-infection. For patients that are HIV-1 negative, the appropriate contraindication must be considered according to the specific recommendations for the patient. For example, if a patient has a contraindication for Biktarvy and does not have significant health or laboratory issues to suggest that the patient should receive treatment with Biktarvy, the doctor making the decision should provide the reason for questioning the determination. On the other hand, if the doctor who is going to approve the treatment feels that the patient's well-being justifies this complex should be considered authoritative, evidence and any other proof that may be requested in certain cases should be provided.

Future Developments and Conclusion

Thanks to modern technologies, a lot of active research is being conducted both in using cccDNA as a potential target for treatment of hepatitis B and exploring the oncolytic potential of the virus. Currently, some researchers are keen to explore the possibility of using gene editing technologies to eliminate the cccDNA from infected cells. These approaches involve developing viral vector systems which can be used to express CRISPR components in infected cells. These targeting sequences can be designed to specifically target sequences on the cccDNA for destruction. By using this approach, the existing cccDNA will be destroyed and will not be passed on to daughter cells when the infected cell divides. This promises to provide a long-term cure for chronic hepatitis B infections. On the other hand, data coming from clinical trials is revealing that the viral oncoprotein HBX can greatly promote cccDNA formation and stability in infected cells, making it a potential target for anti-cancer and anti-cccDNA treatments. Currently, research is focused on developing new oncolytic therapies which deliver therapeutic genes or oncolytic viruses specifically to liver cells. On top of the standard treatment with Biktarvy, this represents a very exciting prospect for managing chronic hepatitis B infections. As for HBV research in general, more and more attention is being given to the functions and effects of cccDNA in infected cells.

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