CanSino Biologics : SUPPLEMENTAL CIRCULAR PROPOSED CHANGE IN USE OF PROCEEDS FROM A SHARE OFFERING AND SUPPLEMENTAL NOTICE OF 2020 ANNUAL GENERAL MEETING

THIS SUPPLEMENTAL CIRCULAR IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION

If you are in doubt about this supplemental circular, you should consult your stockbroker, other registered dealer in securities, bank manager, solicitor, professional accountant or other professional adviser.

If you have sold or transferred all your shares in CanSino Biologics Inc., you should at once hand this supplemental circular together with the enclosed supplemental form of proxy to the purchaser or transferee or to the bank, stockbroker or other agent through whom the sale or transfer was effected for transmission to the purchaser or transferee.

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this supplemental circular, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this supplemental circular.

This supplemental circular appears for information purpose only and does not constitute an invitation or offer to acquire, purchase or subscribe for any securities of the Company.

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 CIRCULAR

PROPOSED CHANGE IN USE OF PROCEEDS

FROM A SHARE OFFERING

AND

SUPPLEMENTAL NOTICE OF 2020 ANNUAL GENERAL MEETING

This supplemental circular should be read together with the 2020 AGM Circular.

A supplemental notice of the AGM of CanSino Biologics Inc. to be held as originally scheduled at Conference Room, Level 11, CITIC Securities Tower, No. 48 Liangmaqiao Road, Chaoyang District, Beijing, PRC at 1:30 p.m on Friday, May 28, 2021 is being despatched to the Shareholders together with this supplemental circular.

The Supplemental Proxy Form for use at the AGM is enclosed with this supplemental circular. The Supplemental Proxy Form is to be used for the supplemental resolution set out in the supplemental notice and will not affect the validity of duly completed Original Proxy Form in respect of the resolutions set out in the notice of the AGM included in the circular of the Company dated April 20, 2021. Shareholders who intend to appoint a proxy to attend the AGM and vote on the resolution set out in the supplemental notice of AGM shall complete and return the Supplemental Proxy Form in accordance with the instructions printed thereon. For holders of H Shares, please return the Supplemental Proxy Form together with any documents of authority to the Company's H share registrar, Computershare Hong Kong Investor Services Limited at Shops 1712-1716, 17th Floor, Hopewell Centre, 183 Queen's Road East, Wanchai, Hong Kong as soon as possible and in any event not later than 24 hours before the time appointed for holding the AGM. 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. Completion and return of the Original Proxy Form and/or the Supplemental Proxy Form will not preclude you from attending and voting at the AGM, or any adjournment thereof should you so wish.

References to dates and time in this supplemental circular are to Hong Kong dates and time.

May 12, 2021

CONTENTS
	Page
DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	1
LETTER FROM THE BOARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	3
SUPPLEMENTAL NOTICE OF 2020 ANNUAL GENERAL MEETING . . . . . . . .	N-1

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DEFINITIONS

In this supplemental circular, the following expressions have the following meanings unless the context requires otherwise:

"2020 AGM Circular"	the circular of the Company in respect of the AGM dated
	April 20, 2021
"2020 AGM Notice"	the notice of the 2020 AGM of the Company dated April
	20, 2021
"AGM" or "Annual General	the 2020 annual general meeting of the Company to be
Meeting"	held on Friday, May 28, 2021 at 1:30 p.m.
"A Share(s)"	ordinary shares in the share capital of the Company with
	a nominal value of RMB1.00 each and listed on the
	Sci-Tech Innovation Board of the Shanghai Stock
	Exchange and traded in RMB
"A-Share IPO Proceeds"	the net proceeds (after deduction of underwriting
	commissions and related costs and expenses) of
	approximately RMB4,979.5 million received by the
	Company from its A Share Offering
"A Share Offering"	the initial public offering of 24,800,000 A Shares and
	listing of the A Shares of Company on the Sci-Tech
	Innovation Board of Shanghai Stock Exchange on August
	13, 2020
"Board"	the board of Directors
"CanSino Innovative Vaccine	an upgrade and replacement of the construction plan of
Industrial Campus Project"	phase II production facilities originally planned by the
	Company in its A Share Offering prospectus
"Company"	CanSino Biologics Inc. (康希諾生物股份公司), a joint
	stock company incorporated in the PRC with limited
	liability on February 13, 2017, the H Shares of which are
	listed on the Main Board of the Stock Exchange (stock
	code: 6185) and the A Shares of which are listed on
	Sci-Tech Innovation Board of the Shanghai Stock
	Exchange (stock code: 688185)
"Director(s)"	the director(s) of the Company
"Group"	the Company and its subsidiaries

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	DEFINITIONS
"H Share(s)"	overseas listed foreign share(s) in the ordinary share
	capital of the Company with a nominal value of RMB1.00
	each, which are subscribed for and traded in Hong Kong
	dollars and listed on the Stock Exchange
"Hong Kong"	the Hong Kong Special Administrative Region of the
	PRC
"Latest Practicable Date"	May 5, 2021, being the latest practicable date prior to the
	printing of this supplemental circular for ascertaining
	certain information in this supplemental circular
"Listing Rules"	the Rules Governing the Listing of Securities on The
	Stock Exchange of Hong Kong Limited, as amended from
	time to time
"Original Proxy Form"	the form of proxy in respect of the resolutions set out in
	the 2020 AGM Circular
"PRC"	the People's Republic of China, for the purpose of this
	supplemental circular, excluding the regions of Hong
	Kong, Macao Special Administrative Region of the
	People's Republic of China and Taiwan
"Results Announcement"	the annual results announcement of the Company for the
	year ended December 31, 2020 published by the
	Company on March 26, 2021
"RMB" or "Renminbi"	Renminbi, the lawful currency of the PRC
"Share(s)"	ordinary share(s) in the share capital of the Company,
	with a nominal value of RMB1.00 each, comprising A
	Share(s) and H Share(s)
"Shareholder(s)"	holder(s) of the Shares
"Stock Exchange"	The Stock Exchange of Hong Kong Limited
"Supplemental Proxy Form"	a supplemental form of proxy for use at the AGM in
	respect of the resolution as set out in this supplemental
	circular

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LETTER FROM THE BOARD

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)
Executive Directors:	Headquarters and Registered Office in
Dr. Xuefeng YU	the PRC:
Dr. Shou Bai CHAO	401-420, 4th Floor
Dr. Tao ZHU (朱濤)	Biomedical Park
Dr. Dongxu QIU	185 South Avenue
	TEDA West District
Non-Executive Directors:	Tianjin
Mr. Qiang XU (許強)	PRC
Mr. Liang LIN (林亮)
Ms. Nisa Bernice Wing-Yu LEUNG (梁頴宇)	Principal Place of Business
Mr. Zhi XIAO (肖治)	in Hong Kong:
	Room 1901, 19/F
Independent Non-executive Directors:	Lee Garden One
Mr. Shiu Kwan Danny WAI (韋少琨)	33 Hysan Avenue
Ms. Zhu XIN (辛珠 )	Causeway Bay
Mr. Shuifa GUI (桂水發)	Hong Kong
Mr. Jianzhong LIU (劉建忠 )

May 12, 2021

To the Shareholders

Dear Sir/Madam,

SUPPLEMENTAL CIRCULAR

PROPOSED CHANGE IN USE OF PROCEEDS

FROM A SHARE OFFERING

AND

SUPPLEMENTAL NOTICE OF 2020 ANNUAL GENERAL MEETING

1. INTRODUCTION

References are made to (i) the Results Announcement which set out, inter alia, the details of utilization of the A-Share IPO Proceeds; (ii) the 2020 AGM Circular dated April 20, 2021, which sets out the time and venue of the AGM and contains the resolutions to be put forward at the AGM for Shareholders' consideration and approval; and (iii) the announcement dated April 29, 2021 in relation to the proposed change in use of the A-Share IPO Proceeds. This supplemental circular should be read together with the 2020 AGM Circular which contains, inter alia, the 2020 AGM Notice.

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