Doxil (doxorubicin HCl liposome injection)
The following drug information is obtained from various newswires, published
medical journal articles, and medical conference presentations.
Doxil has been approved for the treatment of refractory ovarian
cancer. Doxil is indicated for women with ovarian cancer who have
disease that is refractory to paclitaxel- and platinum-based
chemotherapy regimens, which are current first-line therapies.
Refractory ovarian cancer is defined as disease that progresses
during treatment or within six months after completing treatment.
This indication is based on objective tumor response rates.
With the new indication, Doxil is the first and only liposomal
cytotoxic agent approved to treat a solid tumor. Doxil was
originally approved in 1995 for the treatment of AIDS-related
Kaposi's sarcoma in patients with disease that has progressed
on prior combination therapy or in patients who are intolerant to
Studies evaluating Doxil included three Phase II trials
conducted among women with relapsed or refractory ovarian cancer,
as well as preliminary results of a Phase III randomized trial.
Patients in the Phase II studies with refractory ovarian cancer
demonstrated a 13.8 percent response rate, defined as a reduction
in tumor size of at least 50%. This response rate was supported by
interim analysis of Phase III data.
In clinical trials, the most common side effects reported with
Doxil therapy included reduced white blood cell count
(neutropenia), reduced red blood cell count (anemia), nausea,
soreness of the mouth, vomiting, diarrhea, and constipation.
Mechanism of Action
Doxil is a liposomal formulation of doxorubicin, an intravenous
chemotherapy agent. Doxil uses a novel, targeted delivery system
called STEALTH technology to help evade recognition and uptake by
the immune system. Unlike conventional liposomes, STEALTH liposomes
evade detection and destruction by the immune system so they can
circulate in the body longer. A long circulation time increases the
likelihood that the liposomes and their pharmaceutical contents
will reach their targeted tumor site.