CONTROLLED AND SUSTAINED RELEASE APPROACHES IN DEVELOPING SUITABLE DOSAGE FORMS FOR THE ANTIRETROVIRAL DRUG LAMIVUDINE

Lamivudine is a Nucleoside Reverse Transcriptase Inhibitor (NRTI), licensed for the treatment of HIV, and chronic Hepatitis B. The pharmacokinetic data of Lamivudine shows that, frequent administration for a prolonged period of time (lifelong in AIDS and for one year in hepatitis patients) is necessary to maintain constant therapeutic drug levels in the body, in case of AIDS-the dose is 150 mg twice daily (i.e. multiple times a day) in the form of conventional oral tablets. But the long-term AIDS therapy with the conventional tablets of Lamivudine found to have some drawbacks, such as adverse side effects (sometimes severe) resulting from accumulation of drug in multi-dose long-term therapy; poor patient compliance; and high cost. Designing of controlled and sustained release once-daily formulations of Lamivudine can overcome these problems, and maintaining of systemic drug levels consistently above its target antiretroviral concentration throughout the course of the treatment (which is crucial for the success of AIDS therapy) is also possible with these approaches. This review briefly discusses about the novel dosage forms like controlled release matrix tablets, floating tablets, nanoparticles, microparticles, liposomes, and niosomes; which may possibly suitable for the controlled and/or sustained release of Lamivudine and thus, useful in developing the more effective AIDS therapy with very less or no adverse side effects.