Zidovudine - Viral Resistance

Viral Resistance

Even at the highest doses that can be tolerated in patients, AZT is not potent enough to prevent all HIV replication, and may only slow the replication of the virus and the progression of the disease. During prolonged AZT treatment, HIV has the potential to develop resistance to AZT by mutation of its reverse transcriptase. To slow the development of resistance, physicians generally recommend that AZT be given in combination with another reverse transcriptase inhibitor and an antiretroviral from another group, such as a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor; this type of therapy is known as HAART (Highly Active Anti Retroviral Therapy). AZT has been shown to work additively or synergistically with many antiviral agents such as acyclovir and interferon; however, ribavirin decreases the antiviral effect of AZT.