Announcement on Voluntary Disclosure of the Approval by the National Medical Products Administration of the Clinical Trial Application for 9MW5211 Injection

Securities code: 688062 Securities abbreviation: Maiwei Biotechnology Announcement number: 2026-054 Maiwei (Shanghai) Biotechnology Co., Ltd.

Voluntary Disclosure Regarding Injection Clinical Trial Application

9MW5211

Announcement of approval from the National Medical Products Administration

The company's board of directors and all directors guarantee that the contents of this announcement do not contain any false records, misleading statements or major omissions, and assume legal responsibility for the authenticity, accuracy and completeness of its contents in accordance with the law.

Important content reminder:

Recently, Maiwei (Shanghai) Biotechnology Co., Ltd. (hereinafter referred to as the "Company") received the "Drug Clinical Trial Approval Notice" approved and issued by the National Medical Products Administration. The clinical trial application for 9MW5211 injection for the indication of primary biliary cholangitis (PBC) was approved. Previously, its clinical trial application for the indication of inflammatory bowel disease (IBD) had been approved by the National Medical Products Administration and the FDA respectively. License, clinical trial applications for multiple sclerosis (MS), type 1 diabetes (T1DM) and vitiligo indications have been approved by the National Medical Products Administration; the company is also actively promoting clinical trial applications for other indications. Since drugs have a long research and development cycle and many approval processes, they are easily affected by some uncertain factors. Investors are advised to make prudent decisions and pay attention to guarding against investment risks. The relevant information is now announced as follows:

1. Basic information on drugs

Drug name: 9MW5211 injection

Application matters: Registration of clinical trials of domestically produced drugs

Applicant: Maiwei (Shanghai) Biotechnology Co., Ltd.

Clinical trial notification number: 2026LP02330

Approval conclusion: According to the "Drug Administration Law of the People's Republic of China" and relevant regulations, after review, the clinical trial application for 9MW5211 injection accepted on May 26, 2026 complies with the relevant requirements for drug registration, and it is agreed to conduct clinical trials of this product.

2. Other related information about drugs

9MW5211 is a highly specific scavenging innovative antibody independently developed by the company. It precisely intervenes in the key pathological mechanisms mediated by abnormal immune cells in autoimmune diseases. Abnormal activation and tissue infiltration of immune cells are the core driving factors for the occurrence and development of various autoimmune diseases. The molecules targeted by 9MW5211 are specifically expressed on the surface of pathogenic immune cells and are important biological markers of abnormal activation of these cells. By selectively recognizing and eliminating this population of pathogenic cells, 9MW5211 can effectively block the immune cascade, thereby mitigating disease progression and improving clinical symptoms.

After multiple rounds of molecular engineering optimization, 9MW5211 has demonstrated excellent target selectivity. While achieving efficient blocking, it also significantly reduces the risk of non-specific binding, ensuring that it can achieve deep elimination of pathogenic cells that highly express target proteins. This unique mechanism of action is not only expected to bring deeper disease relief, but may also support longer dosing intervals, thereby improving patients' treatment compliance and quality of life.

Preclinical research results show that 9MW5211 has demonstrated significant therapeutic potential in a variety of mouse autoimmune disease models, and future clinical applications are expected to cover multiple major indications. As of the date of this announcement, the clinical trial application for 9MW5211 for vitiligo, PBC, T1DM, MS and IBD indications has been approved by the National Medical Products Administration, and the clinical trial application for IBD indications has been approved by the FDA. The company is also actively promoting clinical trial applications for other indications. At the same time, safety evaluation conducted in the cynomolgus monkey model showed that it has a good safety profile. As the world's first clinical-stage drug candidate targeting this molecule, 9MW5211 is expected to open a new chapter in precision treatment of autoimmune diseases.

PBC is a chronic autoimmune intrahepatic cholestasis disease. The most common clinical manifestations are fatigue and skin itching. It is globally distributed and can occur in all races and ethnicities. The global annual incidence rate is approximately 1.76/100,000, and the prevalence rate is 14.6/100,000. In 2023, the National Health Commission of the People's Republic of China included PBC in the "Second Batch of Rare Disease Catalog." PBC will present with decompensated manifestations of cirrhosis during the decompensation phase. About 40% of patients respond poorly to the existing first-line treatment drug ursodeoxycholic acid. Drug options are limited in the treatment area of ​​PBC, and significant unmet clinical needs remain.

Vitiligo is characterized by the selective loss of melanocytes, resulting in hypopigmentation of affected skin areas, manifested by depigmentation of the skin, mucous membranes, or hair. The prevalence of vitiligo worldwide is 0.5%~2.0%, and the overall prevalence of vitiligo in my country is about 0.56%. Current treatments for vitiligo include topical drugs, systemic drugs, phototherapy, transplantation, covering, and depigmentation. Although these treatments can promote repigmentation of skin lesions to a certain extent, there are still huge unmet clinical needs. With in-depth research on the pathogenesis of vitiligo, future treatments will be more inclined to achieve more efficient and lasting effects by targeting blocking melanocyte damage and autoimmune responses.

T1DM is a chronic autoimmune disease whose main feature is that the body's immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas, resulting in an absolute lack of insulin, which in turn causes persistent elevation of blood sugar. The current treatment landscape of T1DM still centers on insulin replacement therapy, but its goals and implementation paths have evolved significantly: traditional T1DM treatment mainly focuses on controlling hyperglycemia; while current treatment trends place more emphasis on achieving personalized blood sugar control close to physiological conditions while avoiding hypoglycemia and diabetic ketoacidosis (DKA), while improving quality of life, reducing the risk of chronic complications, and extending healthy lifespan. For T1DM patients, especially newly diagnosed T1DM patients, the "China Diabetes Prevention and Treatment Guidelines (2024 Edition)" emphasizes that the remaining β-cell function should be protected, the occurrence of T1DM complications, and the disability and mortality rates should be reduced. According to the 2025 Global Diabetes Map released by the International Diabetes Federation (IDF), there are 9.15 million type 1 diabetes patients worldwide, including 1.81 million children and adolescents under 20 years old, accounting for 19.8%, 6.28 million patients between 20 and 59 years old, accounting for 68.6%, and 1.06 million patients over 60 years old, accounting for 11.8%. There are 599,000 people in China suffering from type 1 diabetes, including 117,000 children and adolescents under the age of 20.

MS is a chronic autoimmune disease caused by an inflammatory response that damages the protective myelin sheath surrounding nerves in the brain and spinal cord. The number of MS patients worldwide will increase from 2.8 million cases in 2020 to 3 million cases in 2024, and is expected to reach approximately 3.5 million cases in 2035. The number of MS patients in China will increase from 32,800 in 2020 to 33,900 in 2024, and is expected to reach 35,500 in 2035.

IBD is a chronic, relapsing, immune-mediated gastrointestinal disorder that primarily includes ulcerative colitis and Crohn's disease. The number of IBD cases worldwide is increasing steadily. Epidemiological studies show that the number of new IBD patients worldwide will increase from 5.9 million cases in 2019 to 7 million cases in 2023, with a compound annual growth rate of 4.4%. It is expected that the number of new IBD patients worldwide will reach 11.5 million in 2032, with a compound annual growth rate of 5.6% from 2023 to 2032.

3. Risk warning

Because pharmaceutical products are high-tech, high-risk, and high-value-added, the cycle from clinical trials to approval to production is long and involves many steps, making them susceptible to uncertainties. Investors are kindly requested to make prudent decisions and pay attention to preventing investment risks.

The company will actively promote the above-mentioned research and development projects and perform its information disclosure obligations on the subsequent progress of the projects in a timely manner in strict accordance with relevant regulations. For relevant company information, please refer to the company's designated disclosure media and the announcement published on the website of the Shanghai Stock Exchange.

Announcement is hereby made.

Board of Directors of Maiwei (Shanghai) Biotechnology Co., Ltd.

August 1, 2026