RTW Investments, LP and Roderick Wong reported beneficial ownership of 1,300,000 shares of Kalaris Therapeutics common stock, representing 5.7% of the class. The shares are held by RTW-managed funds, with RTW Investments as investment adviser and Dr. Wong as managing partner and CIO.
Both reporting persons have shared voting and dispositive power over the 1,300,000 shares and no sole voting or dispositive power. The 5.7% figure is based on 18,702,418 shares outstanding as of November 5, 2025 plus 4,200,000 shares issued in a December 2025 private placement. The holders certify the stake is held in the ordinary course and not for influencing control.
Positive
None.
Negative
None.
Insights
RTW reports a passive 5.7% position in Kalaris Therapeutics.
RTW Investments and Dr. Roderick Wong disclose beneficial ownership of 1,300,000 Kalaris shares, or 5.7% of the common stock. The shares are held through RTW-managed funds, with shared voting and dispositive power and no sole authority reported.
The percentage is calculated from 18,702,418 shares outstanding as of November 5, 2025 plus 4,200,000 shares issued in a December 2025 private placement. The certification states the position is held in the ordinary course and not for the purpose of changing or influencing control, characterizing it as a passive institutional stake.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
KALARIS THERAPEUTICS, INC.
(Name of Issuer)
Common Stock, $0.0001 par value
(Title of Class of Securities)
482929106
(CUSIP Number)
12/31/2025
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
SCHEDULE 13G
CUSIP No.
482929106
1
Names of Reporting Persons
RTW Investments, LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
1,300,000.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,300,000.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,300,000.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
5.7 %
12
Type of Reporting Person (See Instructions)
IA, PN
SCHEDULE 13G
CUSIP No.
482929106
1
Names of Reporting Persons
Roderick Wong
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
1,300,000.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,300,000.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,300,000.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
5.7 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
KALARIS THERAPEUTICS, INC.
(b)
Address of issuer's principal executive offices:
400 Connell Drive, Suite 5500, Berkeley Heights, NJ, 07922.
Item 2.
(a)
Name of person filing:
This statement is filed by:
(i) RTW Investments, LP ("RTW Investments"), a Delaware limited partnership and the investment adviser to certain funds (the "RTW Funds"), with respect to shares of Common Stock, par value $0.0001 per share (the "Shares") of Kalaris Therapeutics, Inc. (the "Company") directly held by the RTW Funds; and
(ii) Roderick Wong, M.D. ("Dr. Wong"), the Managing Partner and Chief Investment Officer of RTW Investments, with respect to the Shares directly held by the RTW Funds.
The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons."
The filing of this statement should not be construed as an admission that any of the foregoing persons or any Reporting Person is, for the purposes of Section 13 of the Securities Exchange Act of 1934, as amended, the beneficial owner of the Shares reported herein.
(b)
Address or principal business office or, if none, residence:
The address of the business office of each of the Reporting Persons is 40 10th Avenue, Floor 7, New York, New York 10014.
(c)
Citizenship:
RTW Investments is a Delaware limited partnership. Dr. Wong is a citizen of the United States.
(d)
Title of class of securities:
Common Stock, $0.0001 par value
(e)
CUSIP No.:
482929106
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
The information required by Item 4(a) is set forth in Rows 5 - 9 of the cover page for each of the Reporting Persons and is incorporated herein by reference. The percentages set forth in Row 11 of the cover pages are calculated based upon the sum of: (i) 18,702,418 shares of common stock outstanding as of November 5, 2025, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on November 12, 2025 and (ii) 4,200,000 shares of common stock issued in a private placement by the Issuer on December 19, 2025, as reported in the Issuer's Current Report on Form 8-K, filed with the SEC on December 18, 2025.
(b)
Percent of class:
RTW Investments: 5.7%
Dr. Wong: 5.7%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
RTW Investments: 0
Dr. Wong: 0
(ii) Shared power to vote or to direct the vote:
RTW Investments: 1,300,000 Shares
Dr. Wong: 1,300,000 Shares
(iii) Sole power to dispose or to direct the disposition of:
RTW Investments: 0
Dr. Wong: 0
(iv) Shared power to dispose or to direct the disposition of:
RTW Investments: 1,300,000 Shares
Dr. Wong: 1,300,000 Shares
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.
See Item 2. The RTW Funds have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the Shares reported herein.
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
What stake in Kalaris Therapeutics (KLRS) did RTW Investments report?
RTW Investments and Roderick Wong reported beneficial ownership of 1,300,000 Kalaris Therapeutics common shares, representing 5.7% of the outstanding class. The shares are held by RTW-managed funds, with shared voting and dispositive power rather than direct, individual ownership authority.
Who are the reporting persons in this Kalaris Therapeutics (KLRS) Schedule 13G?
The reporting persons are RTW Investments, LP, a Delaware investment adviser, and Roderick Wong, M.D., its Managing Partner and Chief Investment Officer. They report on shares directly held by investment funds advised by RTW Investments, collectively referred to as the Reporting Persons.
How did RTW calculate its 5.7% ownership of Kalaris Therapeutics?
The 5.7% ownership is based on 18,702,418 Kalaris common shares outstanding as of November 5, 2025, plus 4,200,000 shares issued in a December 2025 private placement. RTW’s 1,300,000 shares are measured against this combined share count to determine the percentage.
Does RTW Investments have control intent over Kalaris Therapeutics (KLRS)?
The filing states the securities were acquired and are held in the ordinary course of business and not for changing or influencing control of Kalaris. It also notes they are not held in connection with any transaction having that control-related purpose or effect.
Who actually holds the Kalaris Therapeutics shares reported by RTW Investments?
The RTW Funds directly hold the 1,300,000 Kalaris shares. RTW Investments acts as investment adviser to these funds, and Dr. Roderick Wong is RTW’s Managing Partner and CIO. The filing clarifies this structure when describing beneficial ownership of the reported shares.
What voting and dispositive power does RTW report over Kalaris Therapeutics shares?
RTW Investments and Dr. Wong each report 0 shares with sole voting or dispositive power and 1,300,000 shares with shared voting and shared dispositive power. This means decisions on voting and selling those shares are made jointly rather than by either reporting person alone.
