ANTITUMOR-ACTIVITY OF MITOXANTRONE-LOADED CHITOSAN MICROSPHERES AGAINST EHRLICH ASCITES-CARCINOMA

Glutaraldehyde cross-linked chitosan microspheres containing the antin eoplastic agent mitoxantrone were prepared and the antitumour activity was evaluated against Ehrlich ascites carcinoma in mice by intraperit oneal injections. The tumour inhibitory effect was followed by monitor ing animal survival time and change in body weight for a period of 60 days. While the mean survival time of animals which received 2 mg and 1 mg of free mitoxantrone intraperitoneally was 2.1 and 4.6 days, resp ectively, animals which received 2 mg mitoxantrone via microspheres sh owed a mean survival time of 50 days. Five out of 8 animals treated us ing microspheres lived beyond 60 days. The percentage ratio mean survi val time of the treated group divided by the mean survival time of the untreated group for animals treated using mitoxantrone-loaded chitosa n microspheres containing 2 mg of the drug was 290 compared with 12.2 for those which received 2 mg of the free drug. The antitumour effect of mitoxantrone-loaded microspheres against Ehrlich ascites carcinoma was much higher than that of doxorubicin-loaded microspheres reported by previous workers. Our data demonstrate the potential of mitoxantron e-loaded chitosan microspheres for sustained drug delivery to minimize drug toxicity and maximize therapeutic efficacy.