PC-SPES:A Brief Overview

PC-SPES is a botanically based dietary supplement that has been used by men following prostate cancer treatment to re-duce prostate-specific antigen levels. It is a complex matrix comprising 8 herbs whose known chemistry and biology do not account for the observed clinical activity. Recent disclo-sures have forced the product to be withdrawn from the mar-ket. Aspects of previous scientific research on the product, including clinical information, are reviewed, and some sug-gestions are offered for the future scientific needs of this product. Some thoughts are also offered on what the recall of PC-SPES means for the future scientific directions of the dietary supplement industry. In recent years, a number of botanically based dietary supplements have been introduced into commerce and have become popular as alternative therapies to prescription and over-the-counter drugs. Most of these products have been introduced as palliatives and preventative agents, with the notion that the diverse, deleterious aspects of aging on the human condition can be delayed, or in some way ameliorated. Rarely has a product been introduced specifically to produce a therapeutic effect in a disease state, and it is rarer indeed for a product to be made available for the deli-cate area of cancer chemotherapy. In this context, the product known as PC-SPES stands out as unusual. This article will offer a partial review of some of the salient features relating to background, botanical aspects, chemical constituents, in vitro and in vivo biology, and clinical aspects of this product. In considering this product, it is important to realize that it was sold pri-marily through Internet commerce and to a lesser extent in selective retail markets. Before discussing this product, some background in the regulation of dietary supplement regulation and on the scientific aspects of pharmacognosy that apply to dietary supple-ments is pertinent. Botanically based dietary supplements are regu-lated by the U.S. Food and Drug Administration (FDA) through the Dietary Supplement Health an