Federal health regulators said Monday that the drugmaker Pfizer has agreed to pull a leukemia drug off the market after a follow-up study showed it failed to slow the disease.

The Food and Drug Administration cleared the drug Mylotarg in 2000 under its accelerated approval program, which grants speedy access to drugs that show early promise. The drug was cleared for patients older than 60 with relapsed acute myeloid leukemia, a bone marrow cancer.

But the FDA said a follow-up study was halted last August after researchers reported more deaths among patients taking Mylotarg plus chemotherapy, compared with chemotherapy alone.

The study was intended to show that adding Mylotarg to chemotherapy increased lifespan, which it failed to do.

Mylotarg carries a warning label about a sometimes fatal liver condition called veno-occlusive disease. The FDA said the rate of reports of the disease associated with the drug increased during its time on the market.

The drug will not be available to new patients, according to the FDA statement.

• The Associated Press