📜 What This Document Is 📄

This document is a Form 425, which is a registration statement filed with the SEC. Think of it like a detailed blueprint showing how a company intends to merge with another company. 👉 This filing doesn't represent the merger itself, but rather the legal plan required to get the deal approved. The announcement was triggered by the proposed transaction formalized in the Agreement and Plan of Merger, dated April 14, 2026.

🔬 What the Companies Do 🧬

This filing details two clinical-stage biopharmaceutical companies: Galera Therapeutics and Obsidian Therapeutics. 👉 Both companies are working in the highly specialized field of cell therapy, aiming to develop advanced treatments for solid tumors.

• Galera Therapeutics: Is one of the merging parties whose merger details are part of the filing.
• Obsidian Therapeutics, Inc.: Is a key player in this announcement. They focus on harnessing novel protein-regulation technology to create engineered Tumor-Infiltrating Lymphocyte (TIL) cell therapies. 👉 Their goal is to enhance the effectiveness, persistence, and safety of these cell therapies for solid tumors.

🤝 The Mega-Merger Details 🏰

At the heart of this filing is a massive corporate transaction involving multiple entities. The plan is for Galera to merge with and into Galera Merger Sub, while Obsidian merges with and into Obsidian Merger Sub.

• The Transaction: The merger proceeds under the terms of the Agreement and Plan of Merger, dated April 14, 2026.
• The Structure: After the merger, both Galera and Obsidian will survive, but they will operate as wholly-owned subsidiaries of a newly formed parent company, Gazelle Parent, Inc.
• What This Means: Instead of two separate companies operating, they will become two specialized subsidiaries under a single parent umbrella (Parent), allowing them to combine resources and accelerate development.

🧬 The Clinical Breakthrough Announcement 🌟

The filing includes highly significant, independent news about Obsidian’s leading investigational program, OBX-115. While the merger is the main focus, this clinical update is a massive signal of the company's potential value.

• The Event: On April 21, 2026, Obsidian announced that they would present Phase 2 results for OBX-115 at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting.
• Key Details: The presentation is scheduled as an Oral Abstract Session on Monday, June 1, 2026, in Chicago, IL. The title focuses on "OBX-115 engineered tumor-infiltrating lymphocyte (TIL) cell therapy with regulatable membrane-bound IL15 (mbIL15) in patients with advanced melanoma that has progressed on/after immune checkpoint inhibitors (ICI)."
• The Expertise: The lead author for this presentation is Allison S Betof from the Division of Oncology at Stanford University School of Medicine.

🔬 Inside Look: OBX-115 Technology 🛡️

OBX-115 is the core product driving this exciting clinical news. Understanding this technology is key to understanding the company's value proposition.

• What It Is: OBX-115 is a novel, engineered, autologous TIL cell therapy. "Autologous" means the cells are derived from the patient themselves, and "TIL" stands for Tumor-Infiltrating Lymphocyte.
• The Novel Component: The therapy is unique because it is "armored with pharmacologically regulatable membrane-bound IL15 (mbIL15)." This means the therapy has an added function that can be precisely controlled to enhance its activity.
• The Potential: Obsidian believes OBX-115 has the potential to be a meaningful treatment option for patients with advanced or metastatic melanoma, and other solid tumors, by using both mbIL15 and its proprietary manufacturing process.
• Trial Scope: Obsidian is running this investigation in the Phase 1/2 Agni-01 multicenter trial (NCT06060613), covering advanced solid tumors.

⚙️ Combined Corporate Structure and Ownership 🏢

The merger formalizes the reporting structure for all parties involved. 👉 The Parent entity (Gazelle Parent, Inc.) will be the ultimate corporate shield, housing both Galera and Obsidian as subsidiaries.

• The Goal: The parent structure centralizes the operations of Galera and Obsidian.
• The Entities:
  • Galera Merger Sub: The direct wholly owned subsidiary for Galera.
  • Obsidian Merger Sub: The direct wholly owned subsidiary for Obsidian.
  • Galera: Will survive as a subsidiary of Parent.
  • Obsidian: Will survive as a subsidiary of Parent.

⚠️ Risks and Forward-Looking Statements 🚧

Since any merger or clinical drug development carries risks, the filing includes extensive warnings. These are critical sections because they outline the unknowns.

• Key Risks: The documents emphasize that the actual outcome of the combined company depends on many factors, including:
  • The combined company's ability to correctly estimate its operating and other expenses and its cash runway.
  • The ability to retain key personnel.
  • The results of clinical trials with their product candidates.
  • The ability to obtain and maintain intellectual property and regulatory exclusivities.
• Synergies: The filing mentions that future expected financial and operating results, plans, and objectives are projections and are subject to risk.

📆 Historical Company Reports and Governance 🏛️

For readers who want to perform their own due diligence, the filing directs them to historical documents. 👉 This ensures transparency by pointing to official filings for financial history.

• Where to Find Information:
  • For details on the directors and executive officers of Galera, readers should review the Annual Report on Form 10-K for the year ended December 31, 2025 (filed March 19, 2026).
  • Governance details for the 2026 annual meeting of stockholders are in the Proxy statement (filed April 10, 2026).

📞 Important Contacts for Inquiries 💬

If you have questions about the transaction, the filing specifies a dedicated contact person and email. 👉 This is the direct line for investors and interested parties.

• Contact Person: Caroline Code
• Title: VP Corporate Development and Investor Relations
• Email: [email protected]

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🧠 The Analogy 🧩

Merging two specialized biotech companies is like two master mechanics (Galera and Obsidian) deciding to build a highly sophisticated, single factory (Gazelle Parent). They combine their best tools, their most valuable specialized pieces (the therapies), and their collective knowledge. The result isn't just two mechanics side-by-side; it's a new, much larger, and more powerful facility that can build faster and tackle bigger, more complex engines—like developing next-generation cancer treatments.

🧩 Final Takeaway 🧠

This filing announces a significant corporate merger between Galera and Obsidian, creating a new parent company structure. The most exciting news is the independent clinical update: Obsidian is set to present Phase 2 data for its engineered cell therapy, OBX-115, at ASCO 2026, signaling deep progress in advanced melanoma treatment.