APG-2575, an investigational Bcl-2 inhibitor being developed by Ascentage Pharma, has received orphan drug designation from the U.S. Food and Drug Administration (FDA) for the treatment of acute myeloid leukemia (AML).

This designation is granted to medications with the potential to substantially improve care for rare diseases, defined as those that affect fewer than 200,000 people in the U.S. The designation comes with certain incentives, including a tax credit for clinical trial expenses, fee waivers and possible research grants from the FDA, and seven years of market exclusivity in the U.S., if the medication ultimately is approved.

APG-2575 works by inhibiting the protein Bcl-2, which helps to regulate a process called apoptosis.

Apoptosis is a form of programmed cell death that is involved in many important biological processes. Cancers like AML are characterized by out-of-control cell growth. In many cancers, a contributing factor in this abnormal growth is that the cells do not undergo apoptosis when they normally would, so the cells continue to grow when they normally would die.

In cells, the Bcl-2 protein acts as an inhibitor of apoptosis. So, by blocking the activity of Bcl-2, APG-2575 is designed to promote cancer cells to undergo apoptosis, thus killing the cells.

AML is the fourth condition for which the FDA has designated APG-2575 as an orphan drug. The medication also received FDA orphan drug designation for the treatment of Waldenström macroglobulinemia (WM), chronic lymphocytic leukemia (CLL), and multiple myeloma (MM). Similar to AML, all of those conditions are blood cell cancers, though the exact biological processes and cells involved differ.

With the new designation, four of Ascentage Pharma’s investigational drug candidates have been granted a total of nine orphan drug designations by the FDA in 2020. According to Ascentage, this is a record number for any Chinese biopharmaceutical company.

“Receiving nine ODDs [orphan drug designations] from the FDA in just a year is record-setting, by speed and number, among Chinese biopharmaceutical companies; it is also an impressive achievement even by global standard,” Dajun Yang, PhD, Ascentage’s chairman and CEO, said in a press release.

“This accomplishment is a result of our unwavering commitment to our founding mission of ‘addressing unmet medical needs in China and around the world’. I hope that with the various policy supports for ODD designated therapies, we will be able to accelerate the clinical development of our drug candidates, which hopefully can soon benefit patients in need.”