General Information

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 such therapy.

Clinical Results

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.

Side Effects

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.