"We found that using prednisone following a response to up-front chemotherapy was an effective and safe way to prolong the lives of patients," said James Berenson, M.D., lead author. "This is the first clear demonstration that long-term treatment following an initial response to chemotherapy improves the survival of patients with multiple myeloma."

Currently, most patients with multiple myeloma receive initial treatment with chemotherapy or with high-dose chemotherapy followed by a stem cell transplant, and many enter remission. However, all patients ultimately relapse with incurable disease, leading physicians to search for ways to prolong remission by using some type of maintenance therapy.

Although some studies have shown that interferon slightly prolongs remission in these patients, it has not been shown to improve survival. Steroids have been found to inhibit malignant cell growth. Prednisone has been evaluated in combination with interferon as maintenance therapy; some studies have shown that the combination prolongs remission. However, no studies to date had examined whether prednisone alone could prolong remission as well as improve overall survival.

"We wanted to find out whether prednisone alone, a drug that was easy to take and had fewer side effects, was effective as maintenance therapy without the toxicities and costs associated with interferon," said Dr. Berenson.

In the current study, researchers compared patients receiving prednisone following a response to treatment with one of two chemotherapy combinations: vincristine, doxorubicin, and dexamethasone with prednisone --- with or without quinine, a compound that has been found to increase the effectiveness of chemotherapy. Treatment with either of the chemotherapy combinations was repeated every 21 days for at least six months or until patients achieved at least a 25 percent reduction in tumor size. After a 53-month follow-up period, the investigators found that there was no difference in either progression-free or overall survival between the patients who received chemotherapy with quinine and those who received chemotherapy without it.

To determine whether prednisone alone was effective as maintenance therapy, patients who responded to treatment with up-front chemotherapy were randomly selected to receive either 10 mg or 50 mg of prednisone every other day until disease progressed. From the time that maintenance therapy started, the researchers found that patients receiving the higher dose of prednisone remained free of disease progression for 14 months versus 5 months for patients receiving the lower dosage. Most importantly, the investigators found that patients receiving the higher doses of prednisone lived significantly longer (37 months versus 26 months with the lower dose).

"We found that the long-term use of prednisone delayed progression of the disease and kept patients alive longer. Furthermore, 50 mg of prednisone every other day was well tolerated, which means that patients remain active and have a much better quality of life for longer," said Dr. Berenson.

Future studies will examine whether prednisone is effective to prolong remission for patients with other cancers such as leukemia or lymphoma. In addition, other drug combinations that include prednisone will be evaluated as maintenance therapy for patients with multiple myeloma.