X0202 SCHEDULE 13D/A 0001415889-25-008979 0001699737 XXXXXXXX LIVE 3 Common Stock, $0.0001 par value per share 05/20/2026 false 0001754068 482929106 KALARIS THERAPEUTICS, INC.

400 Connell Drive, Suite 5500 Berkeley Heights NJ 07922

Srinivas Akkaraju (650) 285-4270 Samsara BioCapital GP, LLC 628 Middlefield Road Palo Alto CA 94301 0001699737 N Samsara BioCapital, L.P. b WC N DE 0.00 10657028.00 0.00 10657028.00 10657028.00 N 44.8 PN 0001888829 N Samsara BioCapital GP, LLC b AF N DE 0.00 10671965.00 0.00 10671965.00 10671965.00 N 44.9 OO 0002086193 N Samsara Opportunity Fund, L.P. b WC N DE 0.00 2224147.00 0.00 2224147.00 2224147.00 N 9.3 PN 0002086456 N Samsara Opportunity Fund GP, LLC b AF N DE 0.00 2224147.00 0.00 2224147.00 2224147.00 N 9.3 OO 0001253170 N Srinivas Akkaraju b AF N 8000.00 12900583.00 8000.00 12900583.00 12900583.00 N 54.2 IN Common Stock, $0.0001 par value per share KALARIS THERAPEUTICS, INC. 400 Connell Drive, Suite 5500 Berkeley Heights NJ 07922 This Amendment No. 3 (this "Amendment No. 3" or this "Schedule 13D/A") amends and supplements the statement on Schedule 13D originally filed with the Securities and Exchange Commission (the "SEC") on March 25, 2025 and amended on December 22, 2025 and February 17, 2026 (as amended, the "Statement") by the Reporting Persons. Unless otherwise defined herein, capitalized terms used in this Amendment No. 3 shall have the meanings ascribed to them in the Statement. Unless amended or supplemented below, the information in the Statement remains unchanged. Item 3 of the Statement is hereby amended and supplemented as follows: On May 20, 2026, Samsara Opportunity Fund purchased 244,300 shares of common stock from Samsara LP in a private sale for $4.83 per share, or an aggregate purchase price of $1,179,969.00. These shares represented shares held by Samsara LP for the exclusive benefit of limited partners who had redeemed their respective interests in Samsara LP and in which neither Samsara GP nor Dr. Akkaraju had any economic interest. These purchases were for cash and were funded by capital contributions from the general and limited partners of Samsara Opportunity Fund. Rows 11 and 13 of each Reporting Person's cover page to this Schedule 13D/A set forth the aggregate number of shares of common stock and percentages of the shares of common stock beneficially owned by such Reporting Person and are incorporated by reference. The percentage set forth in each row 13 is based upon 23,792,278 shares of common stock outstanding as of May 5, 2026, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on May 12, 2026, and giving effect to stock options, to the extent exercisable within 60 days hereof, as referenced herein. The Reporting Persons' ownership of the Issuer's securities consists of (i) 10,657,028 shares of common stock directly held by Samsara LP; (ii) 14,937 shares of common stock directly held by Samsara GP; (iii) 2,224,147 shares of common stock directly held by Samsara Opportunity Fund; (iv) 4,471 shares of common stock directly held by Samsara BioCapital Partners, L.P. ("Samsara BioCapital Partners"); and (v) 8,000 stock options (right to buy) that are currently vested or scheduled to vest within 60 days of this filing held by Dr. Akkaraju. Samsara GP is the sole general partner of Samsara LP and Dr. Akkaraju is the managing member of Samsara GP. Each of Samsara GP and Dr. Akkaraju possesses power to direct the voting and disposition of the securities held by Samsara LP and Samsara GP. Samsara Opportunity GP is the sole general partner of Samsara Opportunity Fund and Dr. Akkaraju is the managing member of Samsara Opportunity GP. Each of Samsara Opportunity GP and Dr. Akkaraju possesses power to direct the voting and disposition of the securities held by Samsara Opportunity Fund. Dr. Akkaraju is the managing member of the general partner of Samsara BioCapital Partners and possesses power to direct the voting and disposition of the securities held by Samsara BioCapital Partners. Rows 7 through 10 of each Reporting Person's cover page to this Schedule 13D/A set forth the number of shares of common stock as to which such Reporting Person has the sole or shared power to vote or direct the vote and sole or shared power to dispose or to direct the disposition and are incorporated by reference. Except as set forth in Item 3 and below, none of the Reporting Persons has effected any transactions with respect to the securities of the Issuer during the past sixty days. On May 20, 2026, Samsara LP made a pro rata in-kind distribution for no consideration of an aggregate of 66,906 shares of common stock. Of the shares distributed by Samsara LP, Samsara GP received 14,937 shares of common stock in respect of redeemed interests of non-managing members of Samsara GP that were retained by Samsara GP, and Samsara BioCapital Partners received 4,471 shares of common stock which were distributed in respect of the redeemed interest of a limited partner of Samsara LP that has been acquired by Samsara BioCapital Partners. No other person is known to have the right to receive or the power to direct the receipt of dividends from, or any proceeds from the sale of, the securities beneficially owned by any of the Reporting Persons. Not applicable. Exhibit 99.1 Joint Filing Agreement (incorporated by reference to Exhibit 99.1 to the Reporting Persons' Schedule 13D/A filed with the SEC on December 22, 2025). Samsara BioCapital, L.P. /s/ Srinivas Akkaraju 05/22/2026 Samsara BioCapital GP, LLC /s/ Srinivas Akkaraju 05/22/2026 Samsara Opportunity Fund, L.P. /s/ Srinivas Akkaraju 05/22/2026 Samsara Opportunity Fund GP, LLC /s/ Srinivas Akkaraju 05/22/2026 Srinivas Akkaraju /s/ Srinivas Akkaraju 05/22/2026