Table of Contents
- 1 What feature of the reverse transcriptase enzyme is primarily responsible for the acquired resistance to drugs such as AZT?
- 2 What is the rationale for treating individuals with HIV with at least two different classes of antiretroviral therapies arts?
- 3 How does AZT prevent viral replication?
- 4 Why are antiretroviral drugs given in combination?
- 5 How does AZT affect the process of reverse transcription?
- 6 Does AZT inhibit DNA polymerase?
- 7 Do kinase-targeted antibodies have a role in cancer treatment?
- 8 Can tytyrosine kinase inhibitors help in the fight against cancer?
What feature of the reverse transcriptase enzyme is primarily responsible for the acquired resistance to drugs such as AZT?
HIV-1 reverse transcriptase (RT) contributes to the development of resistance to all anti-AIDS drugs by introducing mutations into the viral genome. At the molecular level, mutations in RT result in resistance to RT inhibitors.
Combination antiretroviral therapy drug regimen classes
- Prevent the virus from replicating and reduce viral load.
- Help restore CD4 counts and immune function.
- Reduce complications from HIV and improve survival.
- Reduce transmission of HIV to others.
What are the targets of antiretroviral therapy for HIV and how do the drugs work?
Current targets for antiretroviral therapy (ART) include the viral enzymes reverse transcriptase and protease. The use of a combination of inhibitors targeting these enzymes can reduce viral load for a prolonged period and delay disease progression.
What is combination antiretroviral therapy?
Treatment that uses a combination of three or more drugs to treat HIV infection. Combination antiretroviral therapy stops the virus from making copies of itself in the body. This may lessen the damage to the immune system caused by HIV and may slow down the development of AIDS.
AZT is an azido analog of thymidine, one of the four building blocks that make up DNA. After being activated by phosphorylation in vivo, AZT inhibits HIV replication by blocking a critical HIV enzyme called reverse transcriptase.
Combination therapy has been shown to dramatically reduce the likelihood of drug resistance (many drug-resistant mutations are mutually exclusive) and to suppress viral replication to the point that progression to AIDS is significantly slowed.
What is the best ARV combination?
Summary of Guidelines for Antiretroviral Therapy for HIV Infection. note: Recommended nucleoside analog combinations are as follows: zidovudine + lamivudine; zidovudine + didanosine; zidovudine + zalcitabine; stavudine + lamivudine; or didanosine + stavudine.
How does AZT stop reverse transcriptase?
After being activated by phosphorylation in vivo, AZT inhibits HIV replication by blocking a critical HIV enzyme called reverse transcriptase. This enzyme uses the virus’s RNA genome as a template to build a DNA version that can be inserted into the host’s genome.
How does AZT affect the process of reverse transcription?
AZT interferes with an enzyme called reverse transcriptase (RT), which is used by HIV-infected cells to make new viruses. Since AZT inhibits, or reduces the activity of this enzyme, this drug causes HIV-infected cells to produce fewer viruses.
Does AZT inhibit DNA polymerase?
At very high doses, AZT’s triphosphate form may also inhibit DNA polymerase used by human cells to undergo cell division, but regardless of dosage AZT has an approximately 100-fold greater affinity for HIV’s reverse transcriptase.
Are small-molecule kinase inhibitors the future of cancer treatment?
The recent development of small-molecule kinase inhibitors for the treatment of diverse types of cancer has proven successful in clinical therapy. Significantly, protein kinases are the second most targeted group of drug targets, after the G-protein-coupled receptors.
What is a protein kinase inhibitor?
A protein kinase inhibitor is a type of enzyme inhibitor that can block the action of protein kinases.
Do kinase-targeted antibodies have a role in cancer treatment?
In addition to the small-molecule kinase inhibitors, kinase-targeted antibodies have also demonstrated efficacy in various cancers, for example, cetuximab in colorectal and head and neck cancer, and trastuzumab in breast cancer [ 26, 27 ].
Can tytyrosine kinase inhibitors help in the fight against cancer?
Tyrosine kinase inhibitors therefore provide an important form of targeted therapy in the fight against cancer. Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor’s (MBBS).