Doxorubicin A Less Know Off Label Prostate Cancer Chemotherapy Option

There are different chemotherapy options used to treat castrate resistant prostate cancer (CRPC) which include Taxotere (Doceaxel) and Cabazitaxel (Jevtana) being the most used in today’s clinics. However, there are other chemotherapy drugs that are active and should be considered by you and your doctors.

One possible option not well known in prostate cancer treatment is a drug named Doxorubicin, a chemotherapy drug that is used in other cancers.  For prostate cancer treatment it is best when delivered by injection in combination with other chemotherapy drugs, like Taxotere.

The Doxorubicin compound is made from a bacterium called Streptomyces Peuceticus.   It works by binding to the DNA of cells and inhibiting the cell’s ability to produce a needed protein. Since its delivery method is systemic, it is expected to target and attack cancer tumors even in organs that are distant from the prostate.

Doxorubicin does have a very significant side effect profile that does have a limiting effect on its use.  “Doxorubicin is a widely used cancer chemotherapeutic with significant side effects that include myelosuppression and cardiotoxicity.

Lipid encapsulation of the drug was expected to decrease these toxic side effects, since liposomes can penetrate endothelial lesions found in the neovasculature of tumors but not in normal blood vessels,” stated the study “The Use of Doxil® (Caelyx®) for the Treatment of Prostate Cancer—Past, Present, and Future,” which also added that the compound has leaky vasculature that offers it a capacity to selectively target the tumor.

Doxorubicin to Treat Prostate Cancer

Doxorubicin was approved in the United States since 1991 as a treatment for advanced ovarian cancer and multiple myeloma. It is also often used for breast cancer. 

A very limited number of prostate cancer clinicians have been using it as a less conventional treatment for men with prostate cancer. “There is a pressing need for new agents to treat hormone-refractory prostate cancer (HRPC). Doxorubicin has shown modest activity in this setting, but its use is limited by its toxicities.

Liposomal encapsulation of doxorubicin appears to promote enhanced tumor accumulation in some tumor types, and toxicity appears to be reduced,” explained the authors of the study “Liposomal doxorubicin for the treatment of hormone-refractory prostate cancer.”

During the phase II trial of the study, the investigators concluded that treatment was well tolerated. Monotherapy with doxorubicin had only modest activity in the treatment of castrate resistant prostate cancer, but it is considered an interesting treatment in combination with other types chemotherapy drugs, being the most common Docetaxel.

The same results were demonstrated in the study “Combination Effects of Docetaxel and Doxorubicin in Hormone-Refractory Prostate Cancer Cells,” which showed that the combined chemotherapy drugs lead to high synergy and effective cell death. 

The drugs that have been approved by the FDA, however not for prostate cancer, with doxorubicin hydrochloride as a main active ingredient are commercialized under the brand names Adriamycin PFS, Doxil (liposomal) and Rubex.

Joel T. Nowak, MA, MSW wrote this Post.  Joel is the CEO/Executive Director of Cancer ABCs.  He is a Cancer Thriver diagnosed with five primary cancers - Thyroid, Metastatic Prostate, Renal, Melanoma, and Appendiceal Cancer a rare cancer.

I would like to thank Mike, aka gourd_dancer for a heads up about Doxorubicin.