SCHEDULE: Samsara BioCapital Boosts Kalaris Therapeutics Stake to 56.5%

Samsara BioCapital and its affiliates, led by Srinivas Akkaraju, increased their beneficial ownership in Kalaris Therapeutics to 56.5% following a $15 million investment in a private placement.

Summary

• This Amendment No. 1 to Schedule 13D updates the beneficial ownership of Kalaris Therapeutics, Inc. common stock by Samsara BioCapital, L.P., Samsara BioCapital GP, LLC, Samsara Opportunity Fund, L.P., Samsara Opportunity Fund GP, LLC, and Dr. Srinivas Akkaraju (collectively, the "Reporting Persons").
• On December 17, 2025, Kalaris Therapeutics entered into a securities purchase agreement for a private placement (the "December 2025 Private Placement") of 4,200,000 shares of common stock at $10.00 per share.
• Samsara Opportunity Fund purchased 1,500,000 shares in this private placement for a total consideration of $15 million, funded by capital contributions from its general and limited partners.
• The December 2025 Private Placement closed on December 22, 2025.
• As a result of these transactions, the Reporting Persons' aggregate beneficial ownership in Kalaris Therapeutics is 12,953,581 shares, representing 56.5% of the common stock.
• This percentage is based on 8,702,418 shares outstanding as of November 5, 2025, plus 4,200,000 shares from the December 2025 Private Placement, and 5,500 shares issuable to Dr. Akkaraju upon option exercise within 60 days.
• The Reporting Persons' ownership includes 11,448,081 shares held by Samsara LP, 1,500,000 shares held by Samsara Opportunity Fund, and 5,500 stock options held by Dr. Akkaraju.
• Kalaris Therapeutics also entered into a registration rights agreement on December 17, 2025, obligating the Issuer to register the resale of the 4,200,000 PIPE shares.
• The Issuer is required to file a registration statement by April 1, 2026, plus five days, and use reasonable best efforts to keep it effective until the shares can be resold without registration or volume limitations.

Sentiment

Score: 7

Explanation: The sentiment is moderately positive. Kalaris Therapeutics successfully secured significant funding through a private placement, which is crucial for its operations. The increased stake by a major institutional investor like Samsara BioCapital signals confidence. However, the capital raise also involves dilution for existing shareholders, and the company assumes obligations and potential liabilities related to the registration rights agreement.

Positives

• Kalaris Therapeutics secured $42 million in capital through the December 2025 Private Placement, with Samsara Opportunity Fund contributing $15 million, providing significant funding for the company.
• The substantial increase in beneficial ownership by Samsara BioCapital and its affiliates, reaching 56.5%, demonstrates strong institutional confidence in Kalaris Therapeutics.
• The registration rights agreement provides a clear path for liquidity for the PIPE investors, which can be attractive for future capital raises.

Negatives

• The issuance of 4,200,000 new shares in the private placement at $10.00 per share results in dilution for existing shareholders.
• Kalaris Therapeutics is responsible for all fees and expenses related to the registration of the PIPE shares and may incur liquidated damages if certain deadlines for filing and effectiveness are not met.

Risks

• Kalaris Therapeutics faces the risk of paying specified liquidated damages to the December 2025 PIPE Investors if it fails to meet deadlines for filing, making effective, and keeping effective the resale registration statement for the PIPE shares.

Future Outlook

Kalaris Therapeutics has committed to filing a registration statement covering the resale of the 4,200,000 shares issued in the December 2025 Private Placement as promptly as reasonably practicable following April 1, 2026, and no later than five days thereafter. The company will use reasonable best efforts to ensure the registration statement is declared effective and remains effective until the shares can be resold without registration or volume limitations.

Management Comments

• Dr. Srinivas Akkaraju serves as the Managing Member of Samsara BioCapital GP, LLC, which is the general partner of Samsara BioCapital, L.P., and Samsara Opportunity Fund GP, LLC, which is the general partner of Samsara Opportunity Fund, L.P.

Industry Context

This filing reflects a common financing strategy in the biotechnology sector, where early-stage companies like Kalaris Therapeutics raise capital through private placements with institutional investors, often venture capital firms like Samsara BioCapital. Such investments provide crucial funding for research, development, and operational expenses, while the associated registration rights agreements are standard practice to provide liquidity for the investors' shares.

Comparison to Industry Standards

• The $10.00 per share price for the private placement is a specific valuation point for Kalaris Therapeutics, but without comparable recent private placement valuations for similar-stage biotech companies or specific project milestones, a direct assessment against global benchmarks is not feasible from this filing alone.
• The structure of the private placement with a registration rights agreement is a standard mechanism for institutional investors to gain liquidity for their shares, aligning with common practices in venture capital and growth equity investments in the life sciences sector.

Corporate Governance

Related Party Transactions

• Samsara Opportunity Fund, L.P., a Reporting Person and an affiliate of other Reporting Persons, purchased 1,500,000 shares of Kalaris Therapeutics common stock for $15 million in the December 2025 Private Placement. This constitutes a transaction between the Issuer and a significant beneficial owner/affiliate.

Stakeholder Impact

• Shareholders: Experience dilution from the issuance of new shares in the private placement. However, the capital raise provides funding that could support future growth and value creation.
• Kalaris Therapeutics: Benefits from a $42 million capital injection, which can fund operations and strategic initiatives. Assumes obligations and potential liabilities under the registration rights agreement.
• PIPE Investors (including Samsara Opportunity Fund): Gain a significant equity stake and future liquidity through the registration rights agreement.

Next Steps

• Kalaris Therapeutics is obligated to file a registration statement covering the resale of the December 2025 PIPE Shares as promptly as reasonably practicable following April 1, 2026, and no later than five days after this date.
• The Issuer must use reasonable best efforts to cause the registration statement to be declared effective at the earliest possible date and keep it effective until the PIPE shares can be resold without registration or volume limitations.

Key Dates

Recommendation

The substantial increase in beneficial ownership by Samsara BioCapital and its affiliates, reaching 56.5%, signals strong institutional confidence in Kalaris Therapeutics. The $15 million capital injection from the private placement provides crucial funding. However, this capital raise also involves dilution for existing shareholders. While the registration rights agreement offers future liquidity for the PIPE investors, the immediate impact on the broader market requires further analysis of the company's operational performance and strategic direction, which are not detailed in this ownership filing. Therefore, a 'hold' recommendation is prudent until more comprehensive financial and operational data is available.

Keywords

Kalaris Therapeutics, Samsara BioCapital, Srinivas Akkaraju, Schedule 13D, Private Placement, PIPE, Beneficial Ownership, Biotechnology, Venture Capital, Registration Rights, Equity Investment