Drug from Chinese herb kills tumours in mice, researchers find
A drug made from a plant known as “thunder god vine,” or lei gong teng, that has been used in traditional Chinese medicine has wiped out pancreatic tumours in mice, researchers said, and may soon be tested in humans.
Mice treated with the compound showed no signs of tumours after 40 days or after discontinuing the treatment, according to researchers at the University of Minnesota’s Masonic Cancer Center. The research, funded by the university and the National Institutes of Health, was published Wednesday in the journal Science Translational Medicine.
“This drug is just unbelievably potent in killing tumour cells,” said Ashok Saluja, vice-chairman of research at the centre and the study’s leader, said in a telephone interview. “You could see that every day you looked at those mice, the tumour was decreasing and decreasing, and then just gone.”
The plant, also known as Tripterygium wilfordii, contains triptolide, which earlier studies have shown can cause cancer cells to die. In traditional Chinese medicine, the plant is used as a treatment for rheumatoid arthritis. While the researchers hope to start human trials in six months, Saluja said it is still a long leap from mice to people.
“Does that mean it will definitely work in humans?” he said. “We can definitely not say that.”
The results pave the way for clinical trials in patients with pancreatic cancer, one of the most lethal malignancies, the researchers said in the study. About 44,000 new cases of the disease are diagnosed each year in the United States, according to the U.S. Centers for Disease Control and Prevention in Atlanta. Only about 20 per cent of patients survive a year after diagnosis, Saluja said.
Even for patients diagnosed at the earliest stages of their cancer when the odds are better, only about 14 per cent survive five years or longer, according to the American Cancer Society. The current treatment is Eli Lilly & Co.’s Gemzar, which sold $452 million last year. A generic version of the drug became available in 2011, according to data compiled by Bloomberg.
“It adds six weeks; it’s nothing,” Saluja said. “There’s definitely a need to discover and develop more strategies for pancreatic cancer.”
The researchers dubbed the drug Minnelide, a combination of Minnesota and triptolide. They developed a water-soluble version that could be injected into mice, and in the future administered to patients intravenously.
Saluja and his group have formed a company, Minneamrita Therapeutics, which will attempt to take the drug into the first of three stages of human clinical trials that are generally required before U.S. regulatory approval. Saluja said the company has discussed the trials with the Food and Drug Administration.