Pharmion Corp. shares rose to their highest in more than two years after the company’s treatment for deadly bone-marrow diseases helped patients in a study live longer.

The Boulder-based company’s stock climbed $14.39, or 58.4 percent, to $39.03 in Nasdaq Stock Market composite trading.

Earlier in the day the shares touched $39.88, their highest since Jan. 11, 2005.

The injectable treatment, Vidaza, extended survival by 74 percent in a study of patients with higher-risk myelodysplastic syndromes, diseases in which blood cells in bone marrow don’t function normally, Pharmion said in a statement today. The company plans to seek U.S. regulatory clearance to include the survival data in its packaging for Vidaza, which in 2004 became the first drug approved for this condition.

Each year in the U.S., an estimated 10,000 to 15,000 people, most over the age of 60, are diagnosed with the syndromes, according to the American Cancer Society, a nonprofit group based in Atlanta. Many doctors consider the disease to be a form of cancer because mutated cells form from a single abnormal blood cell and can lead to leukemia, according to the group.