Kalaris Secures $50M to Advance Novel Retinal Disease Therapy

BERKELEY HEIGHTS, N.J. – December 17, 2025 – Kalaris Therapeutics (NASDAQ: KLRS) today announced a significant infusion of capital, securing approximately $50.0 million in an oversubscribed private placement. The financing, backed by a syndicate of prominent new and existing institutional investors, coincides with the release of highly encouraging initial data from the company's lead candidate, TH103, for the treatment of neovascular age-related macular degeneration (nAMD).

This dual development provides a major vote of confidence in the clinical-stage biopharmaceutical company, extending its financial runway into the third quarter of 2027 and accelerating its quest to develop a new generation of treatments for prevalent retinal diseases that are a leading cause of vision loss worldwide.

A Strong Vote of Confidence from Top-Tier Investors

The financing round was notable not just for its size but for its reception. The oversubscribed nature of the private placement indicates that demand from investors exceeded the shares available, a clear signal of robust market confidence in Kalaris's strategy and technology. The securities were sold at a premium to the company's recent trading price, further underscoring the positive sentiment.

The deal includes the sale of 4,200,000 shares of common stock at $10.00 per share and 800,000 pre-funded warrants. Participation came from a distinguished group of life science-focused investors, including ADAR1 Capital Management, Coastlands Capital, Invus, RTW Investments, Samsara BioCapital, and Woodline Partners LP. The involvement of such sophisticated investors validates the company's scientific approach and the potential of its pipeline.

According to the announcement, the net proceeds will be primarily dedicated to advancing the clinical development of TH103. This funding is critical as the company moves forward from its initial positive safety and efficacy signals into a more extensive Phase 1b/2 multiple ascending dose study, which is designed to inform the dose selection for a pivotal Phase 3 program. Morgan Stanley and Leerink Partners acted as lead placement agents for the transaction, a testament to the deal's significance within the sector.

Building on a Legacy: The Promise of TH103

At the heart of this investor enthusiasm is TH103, an investigational therapy that aims to redefine the standard of care for nAMD. The company was founded by the renowned scientist Dr. Napoleone Ferrara, whose pioneering work in isolating vascular endothelial growth factor (VEGF) and developing anti-VEGF therapy revolutionized the treatment of retinal diseases and certain cancers. Kalaris aims to build on that legacy with a novel molecular approach.

TH103 is engineered as a dual-action soluble decoy receptor. It not only binds with high affinity to VEGF—the protein that drives the abnormal blood vessel growth characteristic of nAMD—but it is also designed to bind to heparan sulfate proteoglycans (HSPG) in the retina. This secondary binding mechanism is believed to act as a molecular anchor, significantly extending the drug's residence time within the eye and potentially leading to greater durability and reduced need for frequent injections.

The recent release of positive initial data from the Phase 1a single ascending dose trial provides the first clinical validation of this approach. In treatment-naïve nAMD patients, a single injection of TH103 demonstrated:

• Impressive Visual Gains: Patients experienced a mean gain of +10 letters in best-corrected visual acuity (BCVA) at the one-month mark.
• Robust Anatomical Improvements: The therapy led to a rapid and significant reduction in retinal fluid and swelling, with a mean decrease of 129 μm in central subfield thickness (CST).
• Promising Durability Signal: Perhaps most notably, 31% of patients in the trial required no additional anti-VEGF treatment for a full six months after receiving just one injection of TH103. This early sign of extended duration is a key differentiator in a market clamoring for less burdensome treatments.
• Favorable Safety Profile: The treatment was generally well-tolerated, with a pharmacokinetic profile showing 27 to 51-fold lower systemic exposure compared to leading anti-VEGF agents, aligning with its design for enhanced intraocular retention.

Navigating a Crowded and Evolving Market

Kalaris is not entering an empty field. The nAMD market is a multi-billion dollar space dominated by established therapies like Eylea and Lucentis, with newer entrants like faricimab rapidly gaining market share by offering extended dosing intervals. The bar for a new therapy is exceptionally high, with durability—the ability to maintain efficacy with fewer injections—emerging as the key battleground.

The current standard of care can require patients, who are often elderly, to receive injections directly into the eye as frequently as every one to two months. This significant treatment burden can lead to poor compliance, treatment fatigue, and ultimately, suboptimal vision outcomes. Kalaris's TH103 is positioned to compete directly on this front. If the early durability signal holds up in larger trials, it could offer a compelling alternative for both patients and physicians.

The competitive landscape is also being shaped by a wave of innovation exploring entirely new mechanisms. Gene therapies from companies like Regenxbio and 4D Molecular Therapeutics aim to provide a potential "one-and-done" treatment by enabling the eye to produce its own anti-VEGF medicine. Meanwhile, other companies are exploring tyrosine kinase inhibitors (TKIs) and bispecific antibodies. TH103's approach, which enhances a proven mechanism of action rather than replacing it, may represent a more predictable and potentially safer path to achieving longer-lasting treatment effects.

With the company now well-capitalized through the third quarter of 2027, all eyes will turn to the second half of 2026. Preliminary data from the newly initiated and more extensive Phase 1b/2 multiple ascending dose study is anticipated then, offering the next major glimpse into the future of TH103 and its potential to change the lives of millions suffering from retinal disease.