WuXi Biologics Cayman : VOLUNTARY ANNOUNCEMENT ESTABLISHMENT OF JOINT VENTURE

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WUXI BIOLOGICS (CAYMAN) INC.

藥明生物技術有限公司*

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 2269)

VOLUNTARY ANNOUNCEMENT

ESTABLISHMENT OF JOINT VENTURE

This is a voluntary announcement made by WuXi Biologics (Cayman) Inc. (the "Company", together with its subsidiaries, the "Group") to provide its shareholders and potential investors with information in relation to the latest developments regarding the Company.

The Board is pleased to announce that the Company plans to establish a joint venture company, namely, WuXi XDC (Cayman) Inc. ("WuXi XDC"), with Shanghai SynTheAll Pharmaceutical Co., Ltd. ("WuXi STA"), a subsidiary of WuXi AppTec Co., Ltd. ("WuXi AppTec", the shares of which are listed on Shanghai Stock Exchange (stock code: 603259) and The Stock Exchange of Hong Kong Limited (stock code: 2359)), subject to, among others, the approval by the shareholders of WuXi AppTec. WuXi XDC will engage in the contract development and manufacturing of antibody-drug conjugate ("ADC") and other bioconjugates, and it is intended that the Company and WuXi STA will make capital contributions of USD120 million and USD80 million, respectively, to WuXi XDC. Upon establishment, WuXi XDC will be owned by the Company and WuXi STA as to 60% and 40%, respectively. Accordingly, WuXi XDC will become a non-wholly owned subsidiary of the Company.

The Company and WuXi STA intends for WuXi XDC to be an integrated and end-to-end Contract Development and Manufacturing Organization (CDMO) company specializing in the research, development and manufacturing of ADC and other bioconjugates. Leveraging on the strengths of the Company and WuXi STA in the areas of drug research and development and GMP production of small-molecules, biologics and bioconjugates, the Company believes that WuXi XDC will provide "one-stop" service to better satisfy the growing demand of global customers for research, development and manufacturing services related to such new drug molecules and also simplify the CMC (Chemistry, Manufacturing

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and Control) process and supply chain management of ADC and other bioconjugates and thus, shorten the drug launching process of the Group's business partners to help patients earlier.

The Board would like to emphasize that as at the date of this announcement, the Company has not entered into any legally binding agreement in respect of the establishment of the joint venture company, which is subject to, among others, approval by the shareholders of WuXi AppTec. As such, there is no assurance that the establishment of the joint venture company will proceed and further announcement(s) will be made by the Company as and when required. Therefore, shareholders and potential investors of the Company should exercise caution when dealing in the securities of the Company.

By order of the Board

WuXi Biologics (Cayman) Inc.

Dr. Ge Li

Chairman

Hong Kong, March 30, 2021

As of the date of this announcement, the Board comprises Dr. Zhisheng Chen and Dr. Weichang Zhou as executive Directors; Dr. Ge Li, Mr. Edward Hu, Mr. Yibing Wu and Mr. Yanling Cao as non-executive Directors; and Mr. William Robert Keller, Mr. Teh-Ming Walter Kwauk and Mr. Kenneth Walton Hitchner III as independent non-executive Directors.

*  For identification purpose only

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