If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. Checkbox not checked

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).




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SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 7, 9 and 11: Excludes 31,675 shares of Common Stock underlying unvested stock options held by Bihua Chen. Includes (i) 4,879,995 shares of Common Stock directly held by Cormorant Private Healthcare Fund III, LP ("Fund III"), (ii) 1,905,046 shares of Common Stock directly held by Cormorant Private Healthcare Fund IV, LP ("Fund IV"), (iii) 5,010,332 shares of Common Stock directly held by Cormorant Private Healthcare Fund V, LP ("Fund V"), and (iv) 6,083,221 shares of Common Stock directly held by Cormorant Global Healthcare Master Fund, LP ("Master Fund"). Cormorant Asset Management, LP serves as the investment manager to Fund III, Fund IV, Fund V, and Master Fund. Cormorant Private Healthcare GP III, LLC ("GP III") is the general partner of Fund III; Cormorant Private Healthcare GP IV, LLC ("GP IV") is the general partner of Fund IV; Cormorant Private Healthcare GP V, LLC ("GP V") is the general partner of Fund V; and Cormorant Global Healthcare GP, LLC ("Global GP") is the general partner of the Master Fund. Bihua Chen serves as the managing member of GP III, GP IV, GP V, and Global GP, and as the general partner of Cormorant Asset Management, LP. Accordingly, Ms. Chen has voting and investment discretion with respect to the shares held by each of the Cormorant Funds. Ms. Chen disclaims any beneficial ownership of the securities held by the each of the Cormorant Funds other than to the extent of any pecuniary interest she may have therein, directly or indirectly. Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 7, 9 and 11: Cormorant Private Healthcare Fund III, LP ("Fund III") is the direct holder of such shares. Cormorant Private Healthcare GP III, LLC serves as the general partner of Fund III. Bihua Chen serves as the managing member Cormorant Private Healthcare GP III, LLC. Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 7, 9 and 11: Cormorant Private Healthcare Fund V, LP ("Fund V") is the direct holder of such shares. Cormorant Private Healthcare GP V, LLC serves as the general partner of Fund V. Bihua Chen serves as the managing member Cormorant Private Healthcare GP V, LLC. Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 7, 9 and 11: Cormorant Global Healthcare Master Fund, LP ("Master Fund") is the direct holder of such shares. Cormorant Global Healthcare GP, LLC serves as the general partner of Master Fund. Bihua Chen serves as the managing member Cormorant Global Healthcare GP, LLC. Note to Row 13: Based on an aggregate of 80,107,104 shares of Common Stock outstanding as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission on May 12, 2026.


SCHEDULE 13D






SCHEDULE 13D


 
Bihua Chen
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Self
Date:07/06/2026
 
Cormorant Private Healthcare Fund III, LP
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member of Cormorant Private Healthcare GP III, LLC, General Partner of Cormorant Private Healthcare Fund III, LP
Date:07/06/2026
 
Cormorant Private Healthcare GP III, LLC
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member
Date:07/06/2026
 
Cormorant Private Healthcare Fund V, LP
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member of Cormorant Private Healthcare GP V, LLC, General Partner of Cormorant Private Healthcare Fund V, LP
Date:07/06/2026
 
Cormorant Private Healthcare GP V, LLC
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member
Date:07/06/2026
 
Cormorant Global Healthcare Master Fund, LP
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member of Cormorant Global Healthcare GP, LLC, General Partner of Cormorant Global Healthcare Master Fund, LP
Date:07/06/2026
 
Cormorant Global Healthcare GP, LLC
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member
Date:07/06/2026
 
Helix Holdings II LLC
 
Signature:/s/ Bihua Chen
Name/Title:Bihua Chen, Managing Member
Date:07/06/2026

Exhibit 13

 

JOINDER TO LOCK-UP AGREEMENT

 

July 1, 2026

 

Reference is made to the Lock-Up Agreement, dated as of August 11, 2025, by and among BridgeBio Oncology Therapeutics, Inc., a Delaware corporation (the “Company”) (formerly known as Helix Acquisition Corp. II, a Cayman Islands exempted company, prior to its domestication as a Delaware corporation), Helix Holdings II LLC, a Cayman Islands limited liability company (the “Sponsor”), and the other Holders (as defined therein) from time to time party thereto (as may be amended from time to time, the “Lock-Up Agreement”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Lock-Up Agreement.

 

Section 3 of the Lock-Up Agreement provides that the transfer restrictions set forth in Section 1 of the Lock-Up Agreement do not apply to a Transfer to, among other persons, any members or partners of the Holder or their affiliates, provided that the transferee(s) of such Transfer enter into a written agreement, in substantially the form of this Agreement, agreeing to be bound by these Transfer restrictions.

 

On or about the date hereof, the Sponsor distributed to its members in accordance with the terms of its organizational documents, all of the Lock-Up Shares held by the Sponsor, in the amounts as set forth on Annex A hereto (such shares, the “Distributed Lock-up Shares”), and in connection therewith, such members agreed to enter into this joinder to the Lock-Up Agreement.

 

By executing this joinder, each of the undersigned hereby agrees that, as of the date first set forth above, the undersigned shall become a party to the Lock-Up Agreement and shall be bound by, and shall be subject to the transfer restrictions set forth in the Lock-Up Agreement with respect to the Distributed Lock-up Shares, in the same manner as if such person was an original signatory to the Lock-Up Agreement and as if the Distributed Lock-up Shares were “Lock-up Shares” thereunder.

 

Sections 7 through 9 of the Lock-Up Agreement shall apply to this joinder mutatis mutandis. This joinder may be executed in multiple counterparts, including by means of facsimile or electronic signature, each of which shall be deemed an original, but all of which together shall constitute the same instrument.

 

[Remainder of Page Intentionally Left Blank.]

 

 

 

 

IN WITNESS WHEREOF, the undersigned have duly executed this Joinder as of the date first set forth above.

 

  BRIDGEBIO ONCOLOGY THERAPEUTICS, INC.
     
  By: /s/ Idan Elmelech
  Name: Idan Elmelech
  Title Chief Operating Officer

 

  CORMORANT PRIVATE HEALTHCARE FUND III, LP
     
  By: CORMORANT PRIVATE HEALTHCARE GP III, LLC, its General Partner
     
  By: /s/ Bihua Chen
  Name:  Bihua Chen
  Title Managing Member

 

  CORMORANT PRIVATE HEALTHCARE FUND V, LP
     
  By: CORMORANT PRIVATE HEALTHCARE GP V, LLC, its General Partner
     
  By: /s/ Bihua Chen
  Name:  Bihua Chen
  Title Managing Member

 

  CORMORANT GLOBAL HEALTHCARE MASTER FUND, LP
     
  By: CORMORANT GLOBAL HEALTHCARE GP, LLC, its General Partner
     
  By: /s/ Bihua Chen
  Name:  Bihua Chen
  Title Managing Member

 

 

 

 

Annex A

 

Distributed Lock-up Shares

 

Name  Number of
Shares
 
Cormorant Private Healthcare Fund III, LP   2,692,459 
Cormorant Private Healthcare Fund V, LP   1,704,862 
Cormorant Global Healthcare Master Fund, LP   130,865 
TOTAL   4,528,186 

 

 

 

Exhibit 14

 

JOINT FILING AGREEMENT

 

Pursuant to and in accordance with the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder (the “Exchange Act”) the undersigned hereby agree to the joint filing on behalf of each of them of any filing required by such party under Section 13 of the Exchange Act or any rule or regulation thereunder (including any amendment, restatement, supplement, and/or exhibit thereto) with respect to securities of BridgeBio Oncology Therapeutics, Inc., a Delaware corporation, and further agree to the filing, furnishing, and/or incorporation by reference of this joint filing agreement (this “Agreement”) as an exhibit thereto. Each of them is responsible for the timely filing of such filings and any amendments thereto, and for the completeness and accuracy of the information concerning such person contained therein; but none of them is responsible for the completeness or accuracy of the information concerning the other persons making the filing, unless such person knows or has reason to believe that such information is inaccurate. This Agreement shall remain in full force and effect until revoked by any party hereto in a signed writing provided to each other party hereto, and then only with respect to such revoking party. This Agreement may be executed in any number of counterparts all of which taken together shall constitute one and the same instrument.

 

This agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all of which together shall constitute one and the same instrument.

 

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the 6th day of July, 2026.

 

BIHUA CHEN  
   
/s/ Bihua Chen  
   

 

CORMORANT PRIVATE HEALTHCARE FUND III, LP  
     
By: Cormorant Private Healthcare GP III, LLC  
  its General Partner  

 

By: /s/ Bihua Chen  
  Bihua Chen, Managing Member of Cormorant Private Healthcare GP III, LLC  

 

CORMORANT PRIVATE HEALTHCARE GP III, LLC  
     
By: /s/ Bihua Chen  
  Bihua Chen, Managing Member  

 

 

 

 

CORMORANT PRIVATE HEALTHCARE FUND V, LP  
     
By: Cormorant Private Healthcare GP V, LLC  
  its General Partner  

 

By: /s/ Bihua Chen  
  Bihua Chen, Managing Member of Cormorant Private Healthcare GP V, LLC  

 

CORMORANT PRIVATE HEALTHCARE GP V, LLC  
     
By: /s/ Bihua Chen  
  Bihua Chen, Managing Member  

 

CORMORANT GLOBAL HEALTHCARE MASTER FUND, LP  
     
By: Cormorant Global Healthcare GP, LLC  
  its General Partner  
     
By: /s/ Bihua Chen  
  Bihua Chen, Managing Member of Cormorant Global Healthcare GP, LLC  
     
CORMORANT GLOBAL HEALTHCARE GP, LLC  
     
By: /s/ Bihua Chen  
  Bihua Chen, Managing Member  

 

HELIX HOLDINGS II LLC  
   
By: /s/ Bihua Chen  
  Bihua Chen, Managing Member of Helix Holdings II LLC