Human / Clinical Studies
A prospective clinical series assessed the ability of PC-SPES to lower serum PSA levels in 33 prostate cancer patients. The patients had either refused conventional therapy or had failed previous cryosurgery, radiation therapy, and/or hormonal therapy. No overt signs of disease progression were found in any of the patients. At 2 months, PSA levels had decreased by a mean of 52% in 27 of the 31 patients and had increased in two patients. Of the five patients who had hormone -refractory disease, all had decreased serum PSA levels. Reviewed in [3,6]
In a continuation of the previous study, a total of 69 patients with either AI or AD disease were separated into three study groups. Group one (n = 43) had undergone previous therapy, including hormonal; group two (n = 22) developed AI after treatment; and group three (n = 4) had not undergone previous therapy. The study assessed PC-SPES activity in suppressing PSA levels. Patients were given three capsules of PC-SPES 3 times per day. PSA levels and side effects were observed for 24 months.
In group one, 82% of patients (32 of 39) had a decrease in PSA levels, with 20 patients having a decrease of greater than 50% at 2 months' follow-up; the decrease lasted for 24 months in two patients. In group two (AI patients), 90% (19 of 21) had a decrease in PSA at their 2-month follow-up, with 66% (14 of 21) having a decrease of greater than 50% in PSA levels. At 24 months, two patients had a decrease of 20% to 50% in pretreatment PSA levels. In group three, 50% (2 of 4) had a decrease of greater than 50% in PSA levels at 2 months, and the remaining two patients had an increase at 2 and 6 months. Eighty-two percent of study patients had a decreased PSA level after 2 months of therapy. Side effects included nipple tenderness (42%), gynecomastia (8%), hot flashes, and deep venous thrombosis. In both Germany and the United Kingdom, PC-SPES–like formulations have been studied. A phase I trial of PC-Spes2 in the United Kingdom encountered tolerability problems due to diarrhea.
- Oh WK, Kantoff PW, Weinberg V, et al.: Prospective, multicenter, randomized phase II trial of the herbal supplement, PC-SPES, and diethylstilbestrol in patients with androgen-independent prostate cancer. J Clin Oncol 22 (18): 3705-12, 2004.
- Oh WK, George DJ, Hackmann K, et al.: Activity of the herbal combination, PC-SPES, in the treatment of patients with androgen-independent prostate cancer. Urology 57 (1): 122-6, 2001.
- Pirani JF: The effects of phytotherapeutic agents on prostate cancer: an overview of recent clinical trials of PC SPES. Urology 58 (2 Suppl 1): 36-8, 2001.
- Pfeifer BL, Pirani JF, Hamann SR, et al.: PC-SPES, a dietary supplement for the treatment of hormone-refractory prostate cancer. BJU Int 85 (4): 481-5, 2000.
- Small EJ, Frohlich MW, Bok R, et al.: Prospective trial of the herbal supplement PC-SPES in patients with progressive prostate cancer. J Clin Oncol 18 (21): 3595-603, 2000.
- de la Taille A, Hayek OR, Buttyan R, et al.: Effects of a phytotherapeutic agent, PC-SPES, on prostate cancer: a preliminary investigation on human cell lines and patients. BJU Int 84 (7): 845-50, 1999.
- de la Taille A, Buttyan R, Hayek O, et al.: Herbal therapy PC-SPES: in vitro effects and evaluation of its efficacy in 69 patients with prostate cancer. J Urol 164 (4): 1229-34, 2000.
- Shabbir M, Love J, Montgomery B: Phase I trial of PC-Spes2 in advanced hormone refractory prostate cancer. Oncol Rep 19 (3): 831-5, 2008.