On the morning of June 5th, LONGBIO-B (01779.HK) officially commenced trading on the Main Board of the Hong Kong Stock Exchange.

On its first day of trading, the stock opened 50.22% higher, reaching an intraday peak of HK$158, which represented a gain of 64.48%. At the time of reporting, the share price stands at HK$138.4, marking an increase of 44.08% and giving the company a total market capitalization of approximately HK$10.268 billion.

The global offering consisted of 14,193,150 H shares, with the Hong Kong public offering portion comprising 1,419,350 shares, representing 10% of the total. The application rate for one board lot of 50 shares was 2%. The international placing portion involved 12,773,800 shares, accounting for 90% of the offering.

The final subscription results showed the Hong Kong public offering was oversubscribed by approximately 4,762.58 times, while the international placing was oversubscribed by about 10.94 times.

The final offer price was set at HK$96.06 per share, raising gross proceeds of HK$1.363 billion from the IPO. After deducting listing expenses, the net proceeds are estimated to be around HK$1.255 billion.

Nine cornerstone investors participated in the IPO, including OrbiMed, Zhenmai Investment, Huatai Capital, Ruifeng Fund, Wells Fargo Fund, Value Partners, Greater Bay Area Homeland Development Fund, FR M, Yuanfeng Vision Growth Fund, and China Galaxy International. Together, they subscribed for 7,090,400 shares, involving approximately HK$681 million.

LONGBIO-B was established in 2020 and is a clinical-stage biopharmaceutical company primarily focused on the independent discovery and development of biologic drugs targeting allergic and autoimmune diseases.

The company currently has two main product candidates: (i) its core product, LP-003, an anti-IgE antibody designed to block free IgE in blood and tissues, thereby inhibiting IgE-mediated allergic reactions. It is intended for treating allergic diseases, including seasonal allergic rhinitis (AR), chronic spontaneous urticaria (CSU), allergic asthma, and other allergic conditions. (ii) Its other key product, LP-005, is a bispecific antibody fusion protein targeting complement components C5 and C3b, intended for treating related renal and hematological indications.

Currently, LONGBIO-B is conducting a Phase III clinical trial in China for LP-003 for the seasonal AR indication and plans to submit a Biologics License Application (BLA) to the National Medical Products Administration by or before the third quarter of 2026.

From 2024 to 2025, the company did not generate any revenue or incur any operating costs. However, due to significant research and development expenditures, it recorded net losses of approximately RMB137 million and RMB176 million, respectively, during the same periods.

Following the listing, the board of directors of LONGBIO-B consists of 11 members. This includes three executive directors: Dr. Heng Liu (43, Co-founder, Chairman, CEO, and General Manager), Dr. Naichao Sun (89, Co-founder and Chairman of Xuhua), and Ming Xie (37, Deputy General Manager).

There are four non-executive directors, whose appointments became effective from the company's listing date: Jian Lin (38, Investment Director at Oriental Fortune Capital), Qin Gu (54, Chief Accountant at Shanghai Tongrui Investment), Dr. Di Xue (36, Deputy Director at Honghui Capital), and Dr. Kan Chen (44, Partner at Qiming Venture Partners).

The board also includes four independent non-executive directors: Yaoxi Xiao (65, Independent Director at Jiaoda Angli), Tianshi Ruan (39, CFO at OcuMension Therapeutics), Chun Yang (62, Chairman of Sichuan Luzhou Buchang), and Guofang Zhou (48, General Manager of Shanghai Shishiruyi Medical Devices).

According to the prospectus, the controlling shareholders of LONGBIO-B are Heng Liu, Naichao Sun, Ruoyun Zhou (spouse of Naichao Sun), Suzhou Taiwu, Shanghai Jiuri, and Xuhua. As of the latest practicable date, these shareholders collectively held approximately 44.16% of the company's total issued share capital.

Immediately following the completion of the global offering (assuming the over-allotment option is not exercised), the controlling shareholders will collectively control approximately 35.71% of the total issued share capital of LONGBIO-B.

The intermediary team for this IPO primarily included: Sole Sponsor: Guojin Securities. Overall Coordinator, Joint Global Coordinators, Joint Bookrunners, Joint Lead Managers, and Capital Market Intermediaries: Guojin Securities, GF Securities, ABC International, CCB International, Shanxi Securities International, and Jolly InfoTech. Auditor and Reporting Accountant: Ernst & Young. Industry Consultant: Frost & Sullivan.