Daiichi Sankyo, a Japanese company, has been concentrating on a series of antibody-drug conjugates, but it has achieved a world first in a field that Pfizer is also pursuing. The Japanese government has given Daiichi Sankyo permission to use Ezharmia, also known as valemetostat (DS-3201), to treat adult T-cell leukaemia or lymphoma (ATL) that has relapsed or become resistant to treatment.
According to Wataru Takasaki, Ph.D., head of Daiichi’s Japan R&D, Ezharmia is now the first EZH1/2 dual inhibitor to get authorization anywhere in the world as a result of the approval.
Epizyme’s Tazverik received authorization for epithelioid sarcoma in 2020, making it the first EZH2 inhibitor to receive FDA approval. Tazverik generated $8.9 million in commercial sales in the second quarter following an additional 2020 approval in follicular lymphoma. For about $247 million, Epizyme recently sold itself to Ipsen.
Along with Epizyme, Pfizer recently revealed preliminary results for its investigational EZH2 candidate, PF-06821497, in prostate cancer and follicular lymphoma.
The weakness of EZH2 blocking alone, according to Daiichi’s worldwide R&D leader Ken Takeshita, M.D., may be addressed by a combination of EZH1 and EZH2 inhibition, he said during an investor event in December. The fact that Ezharmia has demonstrated efficacy in both T- and B-cell lymphomas distinguishes it from other treatments that can only reach one form of lymphoma, he continued.
Based on a single-arm phase 2 experiment involving only 25 Japanese patients with three different subtypes of ATL, Japan’s health officials approved Ezharmia. In 48% of patients, including 20% of those who showed no signs of malignancy following therapy, the medication reduced tumour size. According to Daiichi, there are only approximately 3,000 new diagnoses of ATL each year, with 1,000 of those cases occurring in Japan.
In contrast, Daiichi is aiming for a larger market in both its geographic scope and its indications. The company is testing Ezharmia for clinically diagnosed peripheral T-cell lymphoma, including ATL, in the Valentine-PTCL01 global registrational phase 2 research.
According to Takeshita’s presentation in December, Daiichi is working with a French research team on a phase 2 study in individuals with six subtypes of refractory or relapsed B-cell lymphoma for the considerably bigger B-cell lymphoma area.
When Daiichi’s quizartinib, which is marketed in Japan as Vanflyta, was rejected by the FDA in 2019, the company’s blood cancer drug portfolio suffered. Daiichi is aiming for international applications for the medicine in newly diagnosed acute myeloid leukaemia with the FLT3-ITD mutation, including in the U.S. and EU, armed with new patient survival data.
And currently, a lot of Daiichi’s focus is on the antibody-drug conjugate platform, which is headed by the HER2-targeted treatment Enhertu, a collaboration with AstraZeneca. By the end of its fiscal year in 2025, Daiichi said in its new five-year plan, it hopes to generate JPY 1.6 trillion ($11.1 billion) in income, of which JPY 600 billion ($4.2 billion) will come from cancer medications.
