Therapy of a xenografted human colonic carcinoma using cisplatin or doxorubicin encapsulated in long-circulating pegylated stealth liposomes

We compared the therapeutic effects of low doses of cisplatin and doxorubicin hydrochloride encapsulated in long-circulating liposomes composed of cholesterol/hydrogenated soy phosphatidylcholine-polyethylene glycol-distearoyl-phosphatidyl-ethanolamine. The encapsulation of cisplatin and doxorubicin in these liposomes made ineffectively low doses of the free drugs able to inhibit the growth of and affect cures of a human colonic carcinoma growing in nude mice. Liposome-encapsulated cisplatin had minor systemic toxic side effects indicated by an average 9% weight loss which was recovered 3–4 weeks after the last treatment. Toxicity was not observed in mice treated with liposome-encapsulated doxorubicin. Int. J. Cancer 80:134–137, 1999. © 1999 Wiley-Liss, Inc.