Improvement in the antifilarial efficacy of doxycycline and rifampicin by combination therapy and drug delivery approach.

The present investigation deals with the evaluation of antifilarial efficacy of liposome entrapped antiwolbachial antibiotics doxycycline and rifampicin (5 doses at 10 mg/kg, subcutaneously for 15 days) alone and/or in combination with standard filaricide diethylcarbamazine (DEC) against human lymphatic filariid Brugia malayi in rodent host Mastomys coucha. The delivery system maintained the sustained release of antibiotics up to 48 h and significantly (P < 0.05) augmented the antifilarial potential of these antibiotics over their free administration. A combination of DEC with each entrapped antibiotics significantly (P<0.05) improved microfilaricidal efficacy, while marginal enhancement was noticed in adulticidal activity. Combination of both antibiotics formulation with DEC demonstrated marginal increase in macrofilaricidal efficacy; however, it was highest ( approximately 75%).