A team of researchers from Summa Health System, IC-MedTech and other institutions has completed the first ever clinical trial of a drug called Apatone, with promising results in end-stage prostate cancer patients.
The researchers say that Apatone exploits a news strategy to selectively lower the level of compounds within tumour cells that assist in energy production, and protect against chemotherapy.
According to them, this non-toxic approach weakens and kills cancers in a novel way.
"This strategy targets cancer cells by their inflammatory response. It's a different approach than most other anti-tumor drugs, which target dividing cells or the development of blood vessels within the tumor. Since normal cells use sugars or fats for energy and cancer cells rely on glucose, the real key here is that Apatone resembles glucose. As Apatone preferentially accumulates in cancer cells, it also supplies quinone that weakens and can destroy the cancer cell from within," says Dr. James Jamison of Summa Health System.
"The bottom line is: Apatone selectively targets and kills tumor cells using non-toxic biochemistry that protects surrounding healthy tissue," he added.
During the trial, which began in 2005, the safety and effectiveness of the drug was examined in 17 end-stage prostate cancer patients for 12 weeks. The patients took Apatone orally each day.
The researchers monitored prostate-specific antigen (PSA) levels, PSA velocity and PSA doubling times throughout the trial.
Although PSA is a protein normally produced by the prostate gland, individuals with prostate cancer have increased levels. PSA velocity is the change of PSA levels over time and PSA doubling time is the time it takes for a patient's PSA level to double.
"The results of the trial are very promising. Sixteen of the 17 patients responded positively to the Apatone and 13 showed a decrease in PSA velocity and an increase in PSA doubling time. At the end of the treatment period, 15 patients opted to continue treatment," said Dr. Jamison.
He has also revealed that additional clinical trials have been planned for intravenous administration of Apatone in patients who have failed chemotherapy.
"Ultimately, Apatone is intended to be administered intravenously prior to chemotherapy so it can break down the substances in a tumour that protect it from the chemotherapy and allow a greater cell kill. Between cycles and following completion of chemotherapy, Apatone will be taken orally to help prevent or slow tumour regrowth," Dr. Jamison said.
The researchers have not received FDA approval for chemotherapy in conjunction with Apatone as yet.