Liposomes and PLG microparticles as sustained release antitubercular drug carriers--an in vitro-in vivo study

Area of Science:

• Biomedical Engineering
• Drug Delivery Systems
• Pharmaceutical Sciences

Background:

• Tuberculosis (TB) treatment requires effective drug delivery systems.
• Sustained release formulations can improve patient compliance and treatment efficacy.
• Isoniazid (INH) and Rifampicin (RIF) are key antitubercular drugs.

Purpose of the Study:

• To evaluate liposomes and poly(lactic-co-glycolic acid) (PLG) microparticles as carriers for sustained release of isoniazid and rifampicin.
• To compare the in vitro and in vivo performance of these drug delivery systems.
• To assess the hepatotoxicity of the drug-loaded carriers.

Main Methods:

• Liposomes and PLG microparticles were formulated with isoniazid and rifampicin.
• In vitro drug release studies were conducted over several weeks.
• In vivo drug disposition studies in plasma and tissues were performed.
• Hepatotoxicity was evaluated using biochemical tests.

Main Results:

• Liposomes provided sustained release of INH and RIF up to 4 weeks.
• PLG microparticles showed sustained release of INH for up to 6 days and RIF for up to 49 days.
• In vivo studies demonstrated prolonged INH release from liposomes (up to 5 days in tissues) and RIF release (up to 72 hours in tissues).
• PEG-PLG microparticles extended INH release up to 27 days in tissues and RIF release up to 27 days in lungs.
• No significant hepatotoxicity was observed with either carrier system.
• PLG microparticles demonstrated superior sustained drug release compared to liposomes.

Conclusions:

• PLG microparticles are a promising carrier system for sustained delivery of antitubercular drugs.
• Sustained release formulations can potentially enhance tuberculosis treatment outcomes.
• Further investigation into PEG-PLG microparticles for TB therapy is warranted.