Taiho Pharmaceuticals, together with U.S.-based subsidiary Taiho Oncology, has inched closer to approval of another oral combination treatment for patients with blood cancers.
In new phase 3 topline results, Taiho reported that its investigational, all-oral drug combination of azacitidine and cedazuridine successfully treated patients with myelodysplastic syndromes (MDS) or chronic myelomonocytic leukemia (CMML), two blood disorders that can lead to acute myeloid leukemia (AML).
Azacitidine is an established chemotherapy already used to treat MDS and AML. But Taiho’s formulation uniquely pairs the chemo with the cytidine deaminase inhibitor cedazuridine, which blocks the chemo-disintegrating enzyme cytidine deaminase in the digestive tract, allowing the cancer treatment to survive oral delivery.
In practice, azacitidine is today given as an injectable therapy or infusion.
Together, the two treatments in oral form delivered the same exposure to azacitidine as when the chemo was given subcutaneously—meeting Taiho’s primary endpoint for its phase 3 Aztound trial. And the safety profile of the combination therapy was consistent with parenteral azacitidine, too, Taiho and its oncology unit said in a Sept. 30 release.
“The positive topline results … support the potential of an all-oral regimen of azacitidine and cedazuridine to meet the treatment needs of patients with MDS and CMML without the time and treatment burden associated with parenteral therapies,” said Harold Keer, M.D., Ph.D., chief medical officer at Taiho Oncology, in a statement.
The Aztound results build on Taiho’s growing franchise of oral hypomethylating agents—a specific category of low-dose chemotherapy that includes azacitidine and is used to treat blood cancers.
The star player, chemo-defending cedazuridine, was discovered and developed by Taiho’s sister pharma and fellow Otsuka subsidiary, Astex Pharmaceuticals.
In 2020, Inqovi scored its inaugural approval as the first oral chemotherapy option for CMML and MD patients, combining cedazuridine with the chemotherapy and hypomethylating agent decitabine.
In May 2026, Taiho secured another FDA approval for Inqovi, this time in combination with AbbVie and Roche's AML treatment Venclexa (venetoclax), to become the first all-oral regimen for patients with AML.
A similar approval for the azacitidine and cedazuridine combination would mean oral options for both of the CDDL and MDS cornerstone therapies. That could prove an attractive treatment route because patients with CDDL and MDS are, on average, in their 70s. These oral alternatives can have big benefits for treatment adherence compared to taxing visits to the infusion center for IV versions of the therapy.
Based on the topline readout, Taiho said it would submit the Aztound trial results for presentation at an international medical conference, plus the pharma intends to submit a new drug application with the FDA.
“We look forward to pursuing regulatory approval of oral azacitidine and cedazuridine to potentially bring this treatment option to patients,” Keer said.