Daiichi Sankyo bags an industry first with Japanese nod for blood cancer drug Ezharmia

While Daiichi Sankyo has been focusing on a stable of antibody-drug conjugates, the Japanese company has won a global first in an area that Pfizer is also targeting.

Daiichi Sankyo has won Japanese approval for Ezharmia, or valemetostat (DS-3201), to treat relapsed or refractory adult T-cell leukemia/lymphoma (ATL), the company said (PDF) Monday.

The go-ahead makes Ezharmia the first EZH1/2 dual inhibitor to receive regulatory approval anywhere in the world, Daiichi’s Japan R&D head, Wataru Takasaki, Ph.D., noted in a statement.

Back in 2020, Epizyme’s Tazverik became the first FDA-approved EZH2 inhibitor thanks to an accelerated approval in epithelioid sarcoma. After an additional 2020 approval in follicular lymphoma, Tazverik pulled in $8.9 million in commercial sales in the second quarter. Meanwhile, Epizyme recently sold itself to Ipsen for just $247 million.

Besides Epizyme, Pfizer a few days ago unveiled early data for its investigational EZH2 candidate, PF-06821497, in follicular lymphoma and prostate cancer.

Daiichi believes dual EZH1 and EZH2 inhibition may overcome the weakness of EZH2 blocking alone, global R&D chief Ken Takeshita, M.D., explained during an investor event in December. Ezharmia has shown activity in both T- and B-cell lymphomas, which makes it unique in the lymphoma world because the vast majority of agents can only get to one form, he added.

Japan’s health regulators handed out Ezharmia’s approval based on a single-arm phase 2 trial in just 25 Japanese patients with three different subtypes of ATL. The drug shrunk tumors in 48% of patients, including 20% of patients who had no sign of cancer after treatment. ATL is a rare disorder with about 3,000 new diagnoses each year worldwide, including 1,000 in Japan, according to Daiichi.

Meanwhile, Daiichi is targeting a broader market, both in terms of geographic reach and indications. The company is running a global registrational phase 2 study, Valentine-PTCL01, that tests Ezharmia for previously treated peripheral T-cell lymphoma, including ATL.

For the much larger B-cell lymphoma area, Daiichi is collaborating with a French research group on a phase 2 trial in patients with six subtypes of relapsed or refractory B-cell lymphoma, according to Takeshita’s presentation in December.

Daiichi’s blood cancer portfolio took a hit back in 2019 when the FDA rejected the company’s quizartinib, which is sold under the brand name Vanflyta in Japan. Armed with new patient survival data, Daiichi is targeting global applications, including in the U.S. and EU, for the drug in newly diagnosed acute myeloid leukemia with the FLT3-ITD mutation.

And these days, much of Daiichi’s attention is centered on the antibody-drug conjugate platform, which is led by AstraZeneca-partnered HER2-targeted therapy Enhertu. In its new five-year plan unveiled last year, Daiichi said it aims to reach JPY 1.6 trillion ($11.1 billion) in revenue by its fiscal year 2025, with JPY 600 billion ($4.2 billion) from cancer drugs.