Aerosolised liposomal hamycin for treatment of systemic Candida infections in mice

Solid lipid particle-based inhalable sustained drug delivery system against experimental tuberculosis

The present study was planned to evaluate the chemotherapeutic potential of nebulized solid lipid particles (SLPs) incorporating rifampicin, isoniazid and pyrazinamide against experimental tuberculosis. The SLPs prepared by the "emulsion solvent diffusion" technique possessed a favourable mass median aerodynamic diameter suitable for bronchoalveolar drug delivery. Following a single nebulization to guinea pigs, therapeutic drug concentrations were maintained in the plasma for 5 days and in the organs (lungs, liver and spleen) for 7 days whereas free drugs were cleared by 1-2 days. The mean residence time and drug bioavailability were improved several-fold in the case of drug-loaded SLPs. A similar pharmacokinetic profile was observed in Mycobacterium tuberculosis-infected guinea pigs. On nebulization of drug-loaded SLPs to infected guinea pigs at every 7th day, no tubercle bacilli could be detected in the lungs/spleen after 7 doses of treatment whereas 46 daily doses of orally administered drugs were required to obtain an equivalent therapeutic benefit. Further, there was no evidence of any biochemical hepatotoxicity. Thus, nebulization of SLP-based antitubercular drugs forms a sound basis for improving drug bioavailability and reducing the dosing frequency for better management of pulmonary tuberculosis.

Hamycin treatment of candidiasis in normal and diabetic rats

Hamycin, a heptaene antifungal antibiotic was compared with amphotericin B in the treatment of established systemic infection with Candida albicans in normal and diabetic rats. In normal rats, orally administered hamycin at 10 mg kg(-1) per day for 7 days reduced Candida colony counts in the kidneys and livers as well as amphotericin B did and was nearly as effective as amphotericin B in a 21-day treatment trial. There was no further reduction in Candida colony counts when normal rats were treated with hamycin at 25 mg kg(-1) twice a day for 7 days. In streptozotocin induced diabetic rats, hamycin at 20 mg kg(-1) per day for either 7 or 21 days compared favourably with amphotericin B in efficacy. Results of the present study suggest that oral hamycin may be useful in the treatment of established disseminated candidiasis in normal as well as diabetic hosts.