Mabwell (Shanghai) Bioscience Co., Ltd.

Date of Prospectus: April 20, 2026

Mabwell (Shanghai) Bioscience IPO: A Landmark Hong Kong Biotech Listing with Strong Cornerstone Support and Growth Ambitions

Mabwell (Shanghai) Bioscience Co., Ltd. launches a high-profile IPO on the Hong Kong Stock Exchange, targeting substantial capital for clinical development and R&D. With robust cornerstone backing, a focus on innovative oncology therapies, and a transparent, digitally-driven application process, this offering is set to shape the Asia-Pacific biotech landscape. Investors should closely analyze the company’s growth prospects, financials, risk factors, and strategic investor participation to assess potential listing performance.

IPO Snapshot

IPO Symbol: Not explicitly stated; company name: Mabwell (Shanghai) Bioscience Co., Ltd.
Offer Price Range: HK\$27.64 to HK\$30.71 per H Share
Number of Offer Shares: 47,130,200 H Shares (Hong Kong Public Offering: 4,713,200; International Offering: 42,417,000, subject to reallocation)
Expected Market Capitalization (H Shares held by public): Not less than HK\$887.5 million (based on the bottom end of the price range)
Expected Net Proceeds: Approximately HK\$1,255.6 million (assuming Offer Price of HK\$29.18 per H Share, mid-point of range)
Post-IPO Outstanding Shares: Not explicitly stated; can be inferred from offering size and percentages
Listing Date: Expected April 28, 2026

Use of Proceeds: A Growth-Driven Story

Mabwell targets a growth-focused capital deployment:

• 56.8% (HK\$713.0 million): Clinical development trials for Core Product 9MW2821 (an antibody-drug conjugate in oncology, in Phase II/III trials).
• 17.7% (HK\$222.3 million): R&D for pipeline products, focused on oncology and age-related diseases.
• 15.5% (HK\$194.6 million): Expansion of manufacturing capabilities, commercialization, and supply chain.
• 10.0% (HK\$125.6 million): Working capital and general corporate purposes.

If the final offer price is at the range’s high or low end, net proceeds will adjust by approximately HK\$69.4 million, allocated pro rata. This allocation underscores an aggressive growth trajectory, with the vast majority invested in R&D and clinical advancement.

Dividend Policy

No dividends planned in the near future. Mabwell intends to retain all available funds and earnings to support business development and expansion. Future dividends are at the discretion of the Board, subject to business performance, capital needs, and PRC Company Law. No payout ratio or schedule is indicated.

Placement and Issuance Breakdown

Public and Institutional Split:

• Hong Kong Public Offering: 4,713,200 H Shares
• International Offering: 42,417,000 H Shares (subject to reallocation)

Cornerstone Investors: A total of US\$53 million (about HK\$413 million) is committed by six cornerstone investors, with allocations as follows (at mid-point price HK\$29.18):

Lock-up: Cornerstone investors are subject to a six-month lock-up from the Listing Date, with limited exceptions for internal transfers.
Employee allocation: Pre-IPO Equity Incentive Plan has been adopted, but no new grants post-IPO; details are summarized later.

Investor Participation & Book Quality

Strong cornerstone and institutional participation, with top-tier names like Junshi Hong Kong and WuXi Biologics Venture, signals significant institutional confidence in the offering. Pre-IPO investments were completed in March 2020, and all proceeds have been fully utilized, with no pre-listing disposals of shares or material sales by early shareholders indicated.
Book quality appears robust, with 30.19% of the offering anchored by cornerstone commitments.

Deal Parties & Structure

Joint Sponsors: CITIC Securities (Hong Kong) Limited, Haitong International Capital Limited
Joint Global Coordinators/Bookrunners/Lead Managers: Multiple, including the above sponsors (full list within the prospectus)
Underwriters: Hong Kong Underwriters named, with underwriting commission at 2.7% of offer proceeds, plus a discretionary fee up to 1.3% (totaling a maximum of 4.0%).
Sponsor Fees: US\$500,000 per Joint Sponsor.
Stabilization/Greenshoe: Details on overallotment or stabilization activities are referenced as standard under Hong Kong market practice.

The calibre and breadth of bookrunners and sponsors, as well as the significant cornerstone participation, are likely to support stable listing-day trading and aftermarket performance.

Company Overview

Mabwell is a biotechnology innovator focused on the development, application, and commercialization of antibody-based drugs, with a particular emphasis on oncology. The company’s core product, 9MW2821, is an antibody-drug conjugate in Phase II and pivotal Phase III clinical trials targeting cancer indications.
Business Model: Primarily R&D-driven, with revenue streams anticipated from future commercialization of pipeline products and out-licensing agreements.
Customer Segments: Healthcare providers, hospitals, and pharmaceutical partners in China and, prospectively, global markets.
Geographies: China (main base), with expansion plans aligned with global oncology and age-related disease markets.

Industry Size & Position: The company operates within the rapidly expanding global oncology drug market, which has seen significant evolution with the rise of immuno-oncology and targeted therapies.
Unique Market Position: Mabwell is already listed on the Shanghai STAR Market (stock code: 688062) and has been fully compliant with PRC listing requirements. The company has attracted sophisticated investors and maintains a strong regulatory and compliance track record.

Management Team: The Board comprises experienced directors, including controlling shareholder Mr. Tang (executive director), with skills in biotech R&D, commercialization, and international capital markets.

Financial Health

The company’s consolidated financials, prepared under Hong Kong Financial Reporting Standards, indicate:

• Operating Losses: Significant net and operating losses since inception, with expectations to remain loss-making in the near term as R&D investment continues.
• Working Capital: Sufficient to cover at least 125% of estimated costs for at least the next 12 months from the prospectus date, even at the low end of capital raised.
• Listing Expenses: Estimated at HK\$119.4 million, 8.7% of gross proceeds (mid-point price), with professional fees, underwriting commissions, and related costs.
• No Material Adverse Change: As of December 31, 2025 and up to the prospectus date, there has been no material adverse change in financial or operational position.

Trends, Timing & Environment

Sector Trends: The global and China pharmaceutical markets are rapidly evolving, driven by advancements in cancer therapies, immuno-oncology, and targeted drugs such as antibody-drug conjugates.
IPO Timing: The offer period is April 20–23, 2026, with expected listing on April 28, 2026. The window aligns with robust investor demand for innovative biotech plays.
Macro Environment: The prospectus describes a competitive biotech sector with intense rivalry from multinational and domestic players, but also significant growth in demand for oncology therapies.
Recent Developments: Mabwell has completed pre-IPO funding rounds, utilized all proceeds, and maintained compliance since its STAR Market listing in 2022.

Market conditions for this IPO are described as favorable, with strong investor appetite for biotech, robust cornerstone backing, and positive sector momentum.

Risk Factors

Investors should consider material risks:

• Single-Product Risk: Heavy dependence on Core Product 9MW2821, which may not achieve commercialization or regulatory approval.
• Continued Losses: Persistent operating and net losses, with uncertain path to profitability.
• Competitive Intensity: High competition from multinational and domestic pharmaceutical companies.
• Regulatory Uncertainty: Delays or failures in obtaining regulatory approvals could impair revenue generation.
• Customer Concentration: Not explicitly disclosed in detail, but risk exists given early-stage commercial profile.
• Industry Risks: Biotech industry subject to rapid changes, R&D failure risk, and IP challenges.
• Financial Reporting Risks: Only two years of audited results disclosed due to Chapter 18A biotech company status.
• Lock-ups: All cornerstone investors are subject to a six-month lock-up, supporting early market stability.

Growth Strategy

Mabwell’s growth strategy is focused on:

• Accelerating clinical trials and commercialization of its Core Product, 9MW2821, across multiple oncology indications.
• Expanding R&D for additional oncology and age-related disease assets.
• Investing in manufacturing capacity and commercialization infrastructure.
• Pursuing further pipeline development and potentially global market entry, leveraging capital raised in the IPO.

Ownership & Lock-ups

Pre- and Post-IPO Structure: Not all specific percentages are disclosed, but cornerstone investors will hold approximately 30% of the IPO shares. The controlling shareholder, Mr. Tang (via CHIL), participates as a cornerstone investor and maintains significant influence.
Lock-ups: Six months for cornerstone investors; company and controlling shareholders are subject to typical Hong Kong listing lock-ups (six months for new issuance, per Listing Rules).

Listing Outlook

Based strictly on prospectus information, Mabwell’s IPO is well-supported by a strong roster of cornerstone and institutional investors, a clear growth agenda, and robust underwriting. The deal structure, with 30% anchored by cornerstones and a focus on clinical development, suggests the IPO is likely to see solid first-day performance, with post-listing stability further supported by six-month lock-ups. Investors should note the ongoing losses and single-product risk, but the offering appears to be a compelling growth play within the biotech sector.

Based on offer price range, expected allocation, and market context, the first-day trading range is estimated to be within or slightly above the offer price, with potential for upside if market sentiment remains positive and the company delivers on clinical milestones.

Prospectus Access

The prospectus can be accessed at:
www.hkexnews.hk
http://www.mabwell.com

How to Apply

Application Channels:

• HK eIPO White Form Service: www.hkeipo.hk (for investors who wish to receive a physical H Share certificate; apply in your own name)
• HKSCC EIPO Channel: Through your broker or custodian who is a HKSCC Participant (shares allotted in the name of HKSCC Nominees and deposited into CCASS)

Application Window:

• Opens: 9:00 a.m., Monday, April 20, 2026
• Closes: 11:30 a.m., Thursday, April 23, 2026 (for submission); payment deadline 12:00 noon, April 23, 2026

Eligibility: Applicants must be at least 18 years old, outside the United States (unless eligible under Regulation S), and not existing shareholders or connected persons. Full details and steps are available at www.hkeipo.hk and the company’s website.