Lansen Pharmaceutical : VOLUNTARY ANNOUNCEMENT IN RELATION TO FIFTH SHARE REDUCTION PLAN OF STARRY

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LANSEN PHARMACEUTICAL HOLDINGS LIMITED

朗生醫藥控股有限公司

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 503)

VOLUNTARY ANNOUNCEMENT

IN RELATION TO FIFTH SHARE REDUCTION PLAN OF STARRY

Reference is made to the announcements of Lansen Pharmaceutical Holdings Limited (the "Company") dated 9 March 2017, 19 September 2017, 3 April 2018 and 20 February 2019 in relation to share reduction plans (the "First Share Reduction Plan", "Second Share Reduction Plan", "Third Share Reduction Plan" and "Fourth Share Reduction Plan" respectively) of Zhejiang Starry Pharmaceutical Co., Ltd. ("Starry") and announcement of the Company dated 9 May 2019 (the "Announcement") the grant of the Starry Disposal Mandate (as defined below) to the Directors for the disposal of all or part of shares of Starry (the "Starry Shares").

As at the date of this announcement:

1. Lansen HK and Full Keen disposed an aggregate of 4,175,000 Starry Shares under the First Share Reduction Plan and the details of such disposal are set out in the announcement and the circular of the Company dated 15 March 2017 and 28 April 2017 respectively;
2. Lansen HK did not dispose of any Starry Share under the Second Share Reduction Plan;
3. Lansen HK disposed an aggregate of 2,400,000 Starry Shares under the Third Share Reduction Plan and the details of such disposal are set out in the announcement dated 6 June 2018; and
4. Lansen HK and Full Keen disposed an aggregate of 5,278,000 Starry Shares under the Fourth Share Reduction Plan and the details of such disposal are set out in the announcements dated 14 May 2019, 11 June 2019 and 10 September 2019.

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The Company announces that on 11 September 2019 Lansen HK notified Starry about the fifth share reduction plan (the "Fifth Share Reduction Plan") in relation to its holding in the Starry Shares and the key points are:

• Maximum number of Starry Shares that can be disposed: not more than 10,073,900 Starry Shares for Lansen HK, representing not more than 6% of the total number of issued shares in Starry;
• Share reduction period: a period of six month commencing on the third trading day of the Shanghai Stock Exchange immediately following 12 September 2019, the date of Starry's announcement of the Fifth Share Reduction Plan (or a period of six month commencing on the 15th trading day of the Shanghai Stock Exchange immediately following 12 September 2019 for reduction of Starry Shares through centralised competitive bidding on the Shanghai Stock Exchange);
• Methods of share reduction for Lansen HK: through block trade sales or centralised competitive bidding system on the Shanghai Stock Exchange; provided that total amount of share reduction through block trade sales and the centralised competitive bidding system in any consecutive ninety days period shall not exceed 2% and 1% of the total number of issued shares in Starry respectively;
• Share reduction price: with reference to the prevailing trading price of Starry Shares on the Shanghai Stock Exchange.

The notification of the Fifth Share Reduction Plan was given by Lansen HK to Starry in accordance with the relevant rules and regulations of the China Securities Regulatory Commission, governing share reduction by a substantial shareholder holding more than 5% interest in a listed issuer.

As at the date of this announcement, no definitive or legally binding agreement relating to disposal of Starry Shares has been entered into by the Company or Lansen HK. If any disposal under the Fifth Share Reduction Plan materialises, it may constitute a notifiable transaction under Chapter 14 of the Listing Rules.

As disclosed in the Announcement, a general and conditional mandate to the Directors to dispose all or part of the Starry Shares during certain mandate period in accordance with certain terms and conditions (the "Starry Disposal Mandate") were approved by the shareholders of the Company on 9 May 2019. Any disposal under the Fifth Share Reduction Plan will be made in accordance with the terms and conditions of the Starry Disposal Mandate. The Company will comply with the applicable requirements under the Listing Rules and make further announcement(s) in this regard as and when appropriate.

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As the disposal under the Fifth Share Reduction Plan may or may not proceed, shareholders of the Company and potential investors are advised to exercise caution when dealing in the shares of the Company.

By Order of the Board

Lansen Pharmaceutical Holdings Limited

Wu Zhen Tao

Chairman

Hong Kong, 11 September 2019

As at the date of this announcement, the executive managing Director is Mr. Chen Li; the non-executive Directors are Mr. Wu Zhen Tao, Mr. Lee Jin Yi, Mr. Stephen Burnau Hunt and Ms. Liu Xuezi; the independent non-executive Directors are Mr. Chan Kee Huen, Michael, Mr. Fritz Heinrich Horlacher and Mr. Yeung Tak Bun, Allen.

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