Millennium Pharmaceuticals Inc. on Monday said studies show that its drug Velcade is effective for patients at all stages of the bone marrow cancer multiple myeloma.

Velcade, the first of a new class of medicines called proteasome inhibitors, is currently approved for myeloma patients who have tried, and failed, at least two previous therapies.

Multiple myeloma is a cancer in which blood cells grow uncontrollably in the bone marrow, suppressing the development of normal white blood cells, red blood cells and platelets.

In five mid-stage studies unveiled at a meeting of the American Society of Hematology in San Diego, 80 percent to 95 percent of newly diagnosed patients who were given Velcade, either alone or in combination with other commonly used drugs, saw their cancer at least partly regress.

Side effects included neuropathy, fatigue, diarrhea and nerve pain.

“What’s really remarkable is the high degree of complete response rates that we are seeing in these trials - from 10 percent to 30 percent,” said Dr. David Schenkein, the company’s vice president, clinical oncology development.

The company, based in Cambridge, Massachusetts, also unveiled full results from a pivotal-stage trial of Velcade in relapsed myeloma patients showing that the drug alone improved survival, compared with conventional therapy.

The 669-patient trial showed that during the first year, there was an estimated 41 percent reduction in risk of death in patients receiving Velcade compared to those receiving the oral drug dexamethasone, the current standard of care.

“Hopefully we can move this disease into an area where patients can move into remission, either with (bone marrow) transplantation or without,” Schenkein said.

He said Millennium plans to launch pivotal-stage trials of Velcade in previously untreated multiple myeloma patients by the end of this year or early in the first quarter of next year.