Liposomal Doxorubicin and PSC 833 in Treating Patients With AIDS-Related Kaposi's Sarcoma or Other Advanced Cancers
Status:
Completed
Trial end date:
2002-07-01
Target enrollment:
Participant gender:
Summary
The rationale for conducting this study lies in the premise that if indeed the reason for a
limited response of Kaposi's sarcoma lesions and other advanced malignancies to chemotherapy
is attributable to a high expression of P-glycoprotein, then, by inhibiting this pump, tumor
kill would be enhanced and response rates as well as duration of responses would also
increase. Doxil is chosen since recent studies have shown that it is superior to combination
chemotherapy with ABV or BV. Doxil is also known to be active in other malignancies such as
breast and ovarian cancer (34,35). PSC 833 is chosen since it has been found to reverse P-gp
in vitro and in vivo, is non-immunosuppressive, and has been shown in recent Phase 1 studies
to be well tolerated.
There are yet no human studies reported on Doxil pharmacokinetics when combined with MDR
modulators. Preclinical data shows that pharmacokinetics of Doxil, unlike free doxorubicin,
is minimally affected by the addition of PSC 833 (36). Enhanced tumor toxicity was observed
when PSC 833 was combined with Doxil. Since doxorubicin, the active agent in Doxil, is
metabolized by the same cytochrome P450, interactions between these 2 agents may have very
significant clinical implications. The purpose of this study is to assess the toxicity and
determine the maximum tolerated dose of Doxil when combined with PSC 833 in the treatment of
AIDS-KS and other advanced malignancies.