Feb 28 (Reuters) - Patients with relapsed multiple myeloma treated with Amgen Inc's Kyprolis lived more than seven months longer than those who received Takeda Pharmaceutical Co's Velcade, according to data from a late-stage study released by Amgen on Tuesday.

In the head-to-head trial of 929 patients whose multiple myeloma had relapsed following prior treatment, those who received Kyprolis plus low-dose dexamethasone on average lived 47.6 months. That compared with a median survival of 40 months for those who received Velcade plus low-dose dexamethasone.

Earlier published data from the trial called Endeavor demonstrated that patients with the incurable blood cancer who received Kyprolis went significantly longer before the disease worsened than those treated with Velcade, a measure known as progression-free survival (PFS). But helping patients to actually live longer is considered the gold standard.

"We now know that Kyprolis not only significantly extended progression-free survival compared to Velcade, but also overall survival, making it a clinically meaningful advance in the treatment of relapsed or refractory multiple myeloma," Dr. Meletios Dimopoulos, one of the study's lead investigators, said in a statement.

Patients in the study had seen their disease progress after receiving between one and three prior treatment regimens.

Amgen said it will seek to have the Kyprolis label updated to include the new overall survival data, after which the company would be able to promote the benefit.

Kyprolis is approved for multiple myeloma that has progressed after treatment with other medicines.

The prescribing information label already features the PFS data in which patients who received the Amgen drug went twice as long as those who got Velcade before their disease began to worsen, 18.7 months versus 9.4 months.

"Endeavor is the only (relapsed multiple myeloma) study to demonstrate a survival benefit in a head-to-head comparison with a current standard of care regimen," Amgen research chief Sean Harper said in a statement.

In the United States, there are nearly 95,000 people living with, or in remission from, multiple myeloma, according to the National Cancer Institute. About 30,330 Americans are diagnosed with multiple myeloma and more than 12,600 die from the disease each year.

(Reporting by Bill Berkrot; Editing by Jonathan Oatis)