Mesa, Mays Cancer Center play role in getting new medications for blood cancers approved

Contact: Will Sansom, (210) 567-2579,

SAN ANTONIO (Nov. 29, 2021) — With U.S. Food and Drug Administration (FDA) approval in November of a new medication for polycythemia vera (PV), the outlook brightened a bit for patients with that controllable, but chronic, form of blood cancer.

Ruben A. Mesa, MD, FACP, executive director of the Mays Cancer Center, home to UT Health San Antonio MD Anderson Cancer Center, has played a key role as both an investigator and aiding the drug development for the past eight years to get RoPEG INFa2b (besremi) approved in PV.

Photo of Ruben Mesa, MD.
Dr. Ruben Mesa

“Besremi is the first therapy approved for the initial treatment of polycythemia vera where medical treatment is indicated,” said Dr. Mesa, one of the world’s leading investigators in PV and other myeloproliferative neoplasms. “Namely, it is for those PV patients in whom phlebotomy and aspirin are insufficient due to the risk of blood clots or significant symptoms of PV. Besremi helps safely control blood counts in a durable fashion, decrease risk of blood clots and improve disease-associated symptoms.”

PV patients make too many red blood cells in the bone marrow, which can increase the risk of clotting. White blood cells and platelets may also be elevated in some individuals. One treatment is phlebotomy, which, similar to a blood donation, removes some of the blood cells and thins the blood. Another treatment is low-dose aspirin.

Medication treatments to reduce the number of blood cells include hydroxyurea; interferon alfa drugs (including besremi); ruxolitinib; busulfan; and chlorambucil.

Dr. Mesa has investigated PV for 20 years and interferons for much of that time, he said. He was involved with getting ruxolitinib approved, as well.

“The approval of RoPEG INFa2b (besremi) is a big step forward for the treatment of polycythemia vera,” Dr. Mesa said. “As the first FDA-approved interferon for the therapy of polycythemia vera, this class of agents joins jak inhibition as major tools in the arsenal against these diseases. I expect RoPEG INFa2b to help patients with PV live with better controlled disease, decreased risk of progression and improved quality of life.”

The Mays Cancer Center currently co-leads the Global Surpass ET Trial for use of besremi in essential thrombocythemia, another myeloproliferative neoplasm.

The Mays Cancer Center, home to UT Health San Antonio MD Anderson, is one of only four National Cancer Institute-designated Cancer Centers in Texas. The Mays Cancer Center provides leading-edge cancer care, propels innovative cancer research and educates the next generation of leaders to end cancer in South Texas. Visit

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