Amgen scored another victory for its breakthrough multiple myeloma drug on Jan. 21.

The Thousand Oaks-based biotech giant hit it big when the Food and Drug Administration approved revolutionary multiple myeloma drug Kyprolis for treatments with Kyprolis in combination with another drug. The FDA also approved Kyprolis to treat patients on its own for those who have received one or more prior treatments.

When Amgen bought Onyx Pharmaceuticals for $10.4 billion in 2013, it banked on Kyprolis becoming a mainstream cancer drug to treat multiple myeloma. The latest FDA approval is a small step for Amgen, but it opens the market a little more and makes that dream closer to reality.

Multiple myeloma is a form of blood cancer that forms in plasma cells and typically grows in bone marrow, where normal blood cells are formed. Multiple myeloma typically kills patients by producing too many abnormal plasma cells, which interfere with the production of normal blood cells.

Kyprolis works by preventing the breakdown of proteins in cancer cells, which cause the cancer cells to die. There is no cure for the disease, but its effects can be managed.

According to the American Cancer Society, 27,000 Americans will be diagnosed with multiple myeloma in 2015, and 11,000 will die from the disease. The National Cancer Institute said there were 90,000 Americans living with the disease in 2012.

Kyprolis had sales of $331 million in 2014. During the first nine months of 2015, Kyprolis had $364 million in worldwide sales — $333 million of that came from the U.S. alone. By comparison, during the first nine months of 2014, Kyprolis had just $240 million in global sales.

The FDA approved Kyprolis for third-line treatments in 2012. At the time, Richard Pazdur, director of the office of hematology and oncology products at the FDA’s center for drug evaluation and research, said he was impressed by results Kyprolis had shown in early trials.

The FDA approved Kyprolis for second-line treatments on July 24, 2015. On Nov. 19, European regulators approved Kyprolis for patients who received at least one prior treatment for multiple myeloma. The FDA granted this treatment an expedited review on Sept. 18.

• Contact Philip Joens at pjoens@pacbiztimes.com