Takeda Completes Acquisition of IDM Pharma, Inc.

Takeda Pharmaceutical Company Limited ("Takeda", TSE: 4502) today announced the completion of its acquisition of IDM Pharma, Inc. (“IDM”, NASDAQ: IDMI) for US$2.64 per share in cash, through a short-form merger of Jade Subsidiary Corporation (“Jade”), a wholly owned subsidiary of Takeda America Holdings, Inc., which is a wholly owned subsidiary of Takeda, into IDM. With the consummation of the merger, IDM has become a wholly owned subsidiary of Takeda America Holdings, Inc. This acquisition adds MEPACT® (mifamurtide), a novel therapy indicated for the treatment of osteosarcoma, to the Takeda oncology portfolio in Europe.

"With the closing of this acquisition, we look forward to launching MEPACT in Europe. This novel therapy, the first treatment approved for osteosarcoma in more than 20 years, has the potential to benefit patients in an area where new treatments are urgently needed,” said Erich Brunn, CEO of Takeda Pharmaceuticals Europe Limited.

IDM’s common stock will no longer trade on the NASDAQ Global Market. Detailed instructions will be mailed to former IDM stockholders who did not tender their shares in the tender offer that preceded the merger. These instructions will outline the steps to be taken by such former IDM stockholders to obtain the same US$2.64 per share as was paid in the tender offer. The price paid per share is subject to any required tax withholding and no interest will be paid thereon.

About IDM Pharma, Inc.

IDM is focused on the development of innovative cancer products that either destroy cancer cells by activating the immune system or prevent tumor recurrence by triggering a specific adaptive immune response. IDM is dedicated to maximizing the full therapeutic and commercial potential of its innovative products to address the needs of patients and the physicians who treat these patients. For more information about the company and its products, visit www.idm-pharma.com.

About Takeda Pharmaceutical Company Limited

Located in Osaka, Japan, Takeda is a research-based global company with its main focus on pharmaceuticals. As the largest pharmaceutical company in Japan and one of the global leaders of the industry, Takeda is committed to striving toward better health for individuals and progress in medicine by developing superior pharmaceutical products. Additional information about Takeda is available through its corporate website, www.takeda.com.