Mesoblast Acquires Chimeric Antigen Receptor (CAR) Platform Technology for Precision-Enhanced Cell Products

NEW YORK, April 14, 2026 — Mesoblast Limited (Nasdaq:MESO; ASX:MSB), global leader in allogeneic cellular medicines for inflammatory diseases, today announced that it has acquired an exclusive worldwide license to a patented chimeric antigen receptor (CAR) technology platform for precision-enhanced augmentation of therapeutic mesenchymal lineage stromal cell (MSC) products. Mesoblast plans to incorporate the engineered CARs to further boost effectiveness of Mesoblast's products, with the goal of enhancing the target specificity and augmenting inherent properties of immunomodulation and tissue regeneration.

Mesoblast’s MSC technology platforms, including the first and only FDA-approved MSC product in the U.S., are designed for the treatment of tissue-specific inflammatory diseases due to their inherent homing capabilities and immunomodulatory properties. The aim of genetically engineering CAR constructs into MSCs is to substantially enhance targeted homing to inflamed tissue resulting in greater potency.

The foundational work on the CAR technology was developed by investigators at Mayo Clinic and published in *Nature Biomedical Engineering.*1 The investigators identified various CAR-MSCs with potential for enhanced tissue-specific targeting in inflammatory and autoimmune diseases, including to inflamed bowel. This provides Mesoblast with an immediate opportunity to generate products with even greater potency for ulcerative colitis or Crohn's disease. In addition, Mesoblast plans to use CAR-MSC engineered to express CD19 on their surface to induce remission in Lupus Nephritis and other B cell autoimmune diseases where durable, effective and safe immunomodulation is highly desirable.

Mesoblast obtained the worldwide exclusive rights to the CAR-MSC intellectual property developed at Mayo Clinic through the acquisition of a startup formed specifically to advance the technology. As part of the exclusive license, Mayo Clinic will provide in-kind support geared toward further advancing the technology and resulting products, including GMP manufacturing activities. The acquisition was accomplished by Mesoblast through the issuance of ASX ordinary shares.

Silviu Itescu, Chief Executive of Mesoblast, said: "This innovative genetic modification technology fits well with our strategy to extend our market leadership by creating products with even greater efficacy and new target indications."

About Mesoblast

Mesoblast (the Company) is a world leader in developing allogeneic (off-the-shelf) cellular medicines for the treatment of severe and life-threatening inflammatory conditions. The therapies from the Company’s proprietary mesenchymal lineage cell therapy technology platform respond to severe inflammation by releasing anti-inflammatory factors that counter and modulate multiple effector arms of the immune system, resulting in significant reduction of the damaging inflammatory process.

Mesoblast’s Ryoncil® (remestemcel-L-rknd) for the treatment of steroid-refractory acute graft versus host disease (SR-aGvHD) in pediatric patients 2 months and older is the first FDA-approved mesenchymal stromal cell (MSC) therapy. Please see the full Prescribing Information at www.ryoncil.com.

Mesoblast is committed to developing additional cell therapies for distinct indications based on its remestemcel-L and rexlemestrocel-L allogeneic stromal cell technology platforms. Ryoncil® is being developed for additional inflammatory diseases including SR-aGvHD in adults and biologic-resistant inflammatory bowel disease. Rexlemestrocel-L is being developed for heart failure and chronic low back pain. The Company has established commercial partnerships in Japan, Europe and China.

About Mesoblast intellectual property: Mesoblast has a strong and extensive global intellectual property portfolio, with over 1,000 granted patents or patent applications covering mesenchymal stromal cell compositions of matter, methods of manufacturing and indications. These granted patents and patent applications provide commercial protection extending through to at least 2044 in all major markets.

About Mesoblast manufacturing: The Company’s proprietary manufacturing processes yield industrial-scale, cryopreserved, off-the-shelf, cellular medicines. These cell therapies, with defined pharmaceutical release criteria, are planned to be readily available to patients worldwide.

Mesoblast has locations in Australia, the United States and Singapore and is listed on the Australian Securities Exchange (MSB) and on the Nasdaq (MESO). For more information, please see www.mesoblast.com, LinkedIn: Mesoblast Limited and Twitter: @Mesoblast

Note

Mayo Clinic has a financial interest in the technology referenced in this press release through a license agreement with Mesoblast. Mayo Clinic will use any revenue it receives to support its not-for-profit mission in patient care, education and research.

References/Footnotes

• Sirpilla, O. et al. Mesenchymal stromal cells with chimaeric antigen receptors for enhanced immunosuppression. Nat Biomed Eng. 2024 April; 8(4): 443–460.

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