Tai康 Biologics Announces Board Approval of Licensing Agreement with Major Japanese Pharmaceutical Company for HER2 Biosimilar EG1206A in Japan

1. Event Date: June 29, 115 2. Contracting Party: Japanese pharmaceutical company (not disclosed due to confidentiality agreement) 3. Relationship with the Company: None 4. Contract Period (or Termination Date): June 29, 115 – June 28, 125 5. Main Content (not applicable for termination): The company's board of directors has approved the signing of a licensing agreement with a leading Japanese pharmaceutical company for the biosimilar EG1206A in Japan. The company will be responsible for product development, manufacturing, and supply, while the Japanese partner will handle regulatory submissions and commercialization in Japan. 6. Restrictive Clauses (not applicable for termination): As stipulated in the contract. 7. Commitments (not applicable for termination): None. 8. Other Important Agreements (not applicable for termination): None. 9. Impact on Company’s Financials and Operations: Under the agreement, Tai康 Biologics is entitled to receive up to NT$1.32 billion in upfront payments, milestone payments linked to R&D and regulatory achievements, and anticipated sales royalties. In line with biopharmaceutical licensing practices, the licensing fees will be received in installments, contingent upon achieving specified milestones within agreed timelines. Actual revenue recognition will follow accounting standards and depend on R&D progress, regulatory review, market launch timing, sales performance, and contractual terms. The Japanese partner is a well-established, reputable pharmaceutical company with deep industry expertise, proven execution capabilities, and strong familiarity with the Japanese pharmaceutical market. These strengths are expected to provide robust support for EG1206A’s regulatory approval pathway and commercialization preparations in Japan. This collaboration will facilitate the development and expansion of the company’s products in the Japanese market, enhancing visibility and competitiveness. It is expected to have a positive impact on the company’s financial and business development. 10. Specific Purpose: To commercialize and sell the company’s biosimilar EG1206A within the licensed territory. 11. Additional Disclosures (if the subject is a publicly listed company, this material information also qualifies under Article 7, Clause 8 of the Enforcement Rules of the Securities and Exchange Act as a matter significantly affecting shareholder rights or stock prices): (1) New drug development involves long timelines, high investment costs, and no guarantee of success, posing potential investment risks. Investors should exercise caution and make prudent decisions. (2) EG1206A, currently under development by the company, is a biosimilar of Pertuzumab, indicated for the treatment of HER2-positive early breast cancer and metastatic breast cancer. It has received positive feedback from the U.S. FDA and the European Medicines Agency regarding a streamlined, waiver-based Phase III clinical trial pathway and is preparing regulatory submission dossiers as advised by the authorities. (3) According to Roche’s 114 annual report, Pertuzumab achieved global sales of 2.968 billion Swiss francs (approximately USD 3.763 billion), with sales in Japan amounting to 69 million Swiss francs (approximately USD 87.48 million).