CanSino Biologics : SUPPLEMENTAL NOTICE OF 2020 ANNUAL GENERAL MEETING

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CanSino Biologics Inc.

康希諾生 物股份公司

(A joint stock company incorporated in the People's Republic of China with limited liability)

(Stock code: 6185)

SUPPLEMENTAL NOTICE OF 2020 ANNUAL GENERAL MEETING

Reference is made to the notice (the "2020 AGM Notice") of the 2020 annual general meeting (the "AGM") of CanSino Biologics Inc. (the "Company") dated April 20, 2021, which states the time and venue of holding the AGM and the resolutions to be proposed at the AGM for the Company's shareholders' approval. This supplemental notice shall be read together with the 2020 AGM Notice.

SUPPLEMENTAL NOTICE IS HEREBY GIVEN THAT the AGM of the Company will be held at Conference Room, Level 11, CITIC Securities Tower, No. 48 Liangmaqiao Road, Chaoyang District, Beijing, the People's Republic of China on Friday, May 28, 2021 at 1:30 p.m. as originally scheduled, to consider and approve the following resolution in addition to the resolutions set out in the 2020 AGM Notice:

ORDINARY RESOLUTION

11. To consider and approve the proposed change in use of the net proceeds received from the Company's A share offering in August 2020.

For and on behalf of the Board

CanSino Biologics Inc.

Xuefeng YU

Chairman of the Board

Hong Kong, May 12, 2021

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Notes:

1. A supplemental form of proxy (the "Supplemental Proxy Form") containing the ordinary resolution numbered 11 is enclosed with the supplemental circular of the Company dated May 12, 2021 (the "Supplemental Circular").
2. The Supplemental Proxy Form in respect of the above resolution has been enclosed with the Supplemental Circular. The Supplemental Proxy Form is to be used for the supplemental resolution set out in this supplemental notice and will not affect the validity of duly completed form of proxy in respect of the resolutions set out in the 2020 AGM Notice. If you have already appointed a proxy to attend and act on your behalf at the AGM but do not return the Supplemental Proxy Form, your proxy will have the right to vote on the supplemental resolution at his/her discretion. Please refer to the section headed "Proxy Arrangement" on page 5 of the Supplemental Circular for other arrangements on the completion and submission of the Supplemental Proxy Form.
3. Please refer to the Company's circular dated April 20, 2021 and the 2020 AGM Notice for details of ordinary resolutions numbered 1 to 10 and a special resolution to be considered at the AGM, eligibility for attending the AGM, appointment of proxy, registration procedures, closure of register of members and other relevant matters.
4. References to dates and time in this supplemental notice are to Hong Kong dates and time.

As at the date of this supplemental notice, the Board of Directors comprises Dr. Xuefeng YU, Dr. Shou Bai CHAO, Dr. Tao ZHU and Dr. Dongxu QIU as executive Directors, Mr. Qiang XU, Mr. Liang LIN, Ms. Nisa Bernice Wing-Yu LEUNG and Mr. Zhi XIAO as non-executive Directors, and Mr. Shiu Kwan Danny WAI, Ms. Zhu XIN, Mr. Shuifa GUI and Mr. Jianzhong LIU as independent non-executive Directors.

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