By: Hannah Clark for Medtech1
A new drug that could help leukemia patients has successfully completed a Phase 1 clinical trial.
The drug, BMS-354825, helps patients with chronic myelogenous leukemia (CML) who have developed resistance to Gleevec, a highly successful medication that was approved by the U.S. Food and Drug Administration in 2001.
Unlike chemotherapy, Gleevec targets the cancer-causing enzyme without affecting healthy cells. Previously, a CML patient’s only options were a bone transplant or Interferon, a drug that prolonged life but caused unpleasant side effects.
Every year, however, approximately 4 percent of patients develop resistance to Gleevec because of mutations in the enzyme that causes CML. The new drug helps patients with 30 out of 31 of the known mutations. The remaining mutation, unfortunately, causes 20 percent of the resistant cases.
According to researchers, 86 percent of the patients treated with the new drug, developed by Bristol-Myers Squibb, achieved complete hematologic remission, which means their blood counts returned to normal. The disease cannot actually be cured, but it can be managed if patients continue to take medication.
Chronic myelogenous leukemia (CML), which starts in the bone marrow and spreads to the blood, was the cause of death for 1,570 Americans in 2004, according to the American Cancer Society.
Another drug that shows promise for Gleevec-resistant CML, AMN107, is in earlier stages of development. Novartis, which manufactures Gleevec, is also the company behind AMN107.
“The good news for people is there are now two really good looking prospects that are coming out at the same time,” said Dr. Charles Sawyers, one of the leaders of the BMS-354825 research team, who works out of the University of California Los Angeles, and is employed by the Howard Hughes Medical Institute.
Dr. Sawyers and Dr. Moshe Talpaz of the University of Texas recently presented their findings at the annual conference of the American Society of Hematology.
While Phase 1 clinical trial results are often very preliminary, researchers say the BMS-354825 results are significant enough to merit close attention.
“It’s very unusual, but it’s very much the way Gleevec was,” said Dr. Alan Kinniburgh, senior vice president for research at the Leukemia and Lymphoma Society.
“The science behind it is spectacular, plus it is following in the footsteps of a really successful drug,” said Dr. Brian Druker of the Oregon Health & Science University Cancer Institute, whose work led to the development of Gleevec.
Patients with Gleevec-resistant CML will be the first to benefit from the new drug. Ultimately, however, doctors say BMS-354825 may be used in combination with Gleevec before the cancer-causing cells have been given any chance to mutate.
Both of the new drugs are more potent than Gleevec, so they could cause the cancer to go into deeper remission.
While some drugs require Phase 3 trials before FDA approval, Dr. Kinniburgh expects a successful Phase 2 trial will be sufficient for BMS-354825, which means the drug could be on the market within two years. He noted that Gleevec was approved based on a 53-patient Phase 2 trial.
“I would be shocked if a Phase 2 trial weren’t the basis for approval of the drug,” he said.
