Clinical Effects of a Plant Extract Mixture Containing <i>Rhus verniciflua</i> and Other Herbs in Tumor Bearing Dogs

Abstract

Dog owners are increasingly seeking treatment when their pets develop cancers. As in human cancer patients, dogs with cancer are commonly treated with complementary and alternative therapies, including herbal medicines and nutritional supplements. A novel antitumor agent was developed from six different herbs including Rhus verniciflua (Rv-PEM01). The components were established from traditional herbal medicine and designed to affect antitumor activity and maintain host immune function. Previous studies identified anti-proliferative activity in human, murine and canine cancer cell lines. In this clinical study the safety and tolerability of Rv-PEM01 were evaluated in pet dogs with spontaneously occurring cancers. Twelve dogs were treated orally daily for 30 days in escalating dose (4 - 10 mg/kg orally once daily) cohorts. Rv-PEM01 was well tolerated; only transient mild elevations in BUN were observed in 2 dogs. Although tumor response was not a primary endpoint for this study, stable disease was maintained for 30 days in 5 (42%) of the dogs. In conclusion, Rv-PEM01 was found to be safe and well tolerated in the dosage range tested. Future studies should evaluate higher dosages of Rv-PEM01 in dogs with cancer, and specifically address other potential benefits of Rv-PEM01 in canine cancer patients, including correlative assessments of immune function, quality of life and owner satisfaction.