Chugai News Releases are issued to provide stakeholders with the most up-to-date information related to our company. In some instances, information on products or drug candidates under development may be included, but this is intended for members of the media, shareholders, and investors. The information is not intended for promotional or advertising purposes, or as medical advice, etc.

Dec 16, 2021

Update on the Development of Oral COVID-19 Drug Candidate AT-527 in Japan

TOKYO, December 16, 2021 -- Chugai Pharmaceutical Co., Ltd. (TOKYO: 4519) announced that the company will discontinue its development of AT-527, an investigational RNA polymerase inhibitor for COVID-19, in Japan.

On November 16, 2021, it was announced that Roche, a strategic partner of Chugai, and Atea in the U.S., the originator of AT-527, would terminate their partnership for the global joint development of AT-527. Chugai had obtained exclusive development and marketing rights in Japan for AT-527 from Roche in February 2021 and participated in the global phase III study (MORNINGSKY study) from Japan.

In consideration of the decision made by the two companies, Chugai decided to discontinue its efforts to develop AT-527 in Japan. Atea will determine the next steps for the clinical development of AT-527.

“We have decided to no longer pursue the development of AT-527 in Japan, which we started to expand treatment options for COVID-19. The development will be continued by Atea. I’d like to thank everyone who supported us in developing this investigational drug, especially patients and healthcare professionals,” said Chugai’s President and CEO, Dr. Osamu Okuda.

Atea Pharmaceuticals Introduces New Strategic Clinical Development Program for AT-527 in COVID-19 (Press release by Atea issued on December 14, 2021)


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