RA Capital funds boost Bicara Therapeutics (BCAX) stake with stock and warrants

Rhea-AI Filing Summary

Bicara Therapeutics Inc. reported insider purchases by RA Capital–affiliated funds. On February 26, 2026, entities managed by RA Capital Management, L.P. bought 2,200,000 Pre-Funded Warrants at $15.9999 per right and 300,000 shares of common stock at $16.00 per share in open-market or private transactions.

The Pre-Funded Warrants have no expiration date and are exercisable at any time after issuance, but cannot be exercised if the holder and its affiliates would own more than 9.99% of outstanding common stock after exercise. The RA Capital adviser, its general partner, the funds, and principals Dr. Peter Kolchinsky and Mr. Rajeev Shah each disclaim beneficial ownership except to the extent of their pecuniary interests.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

RA CAPITAL MANAGEMENT, L.P.

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Bicara Therapeutics Inc. [ BCAX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
02/26/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	02/26/2026		P		300,000	A	$16	4,603,418	I	See footnotes(1)(2)
Common Stock								2,652,575	I	See footnotes(1)(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Pre-Funded Warrant (Right to Buy)	$0.0001	02/26/2026		P		2,200,000		(4)	(4)	Common Stock	2,200,000	$15.9999	2,200,000	I	See Footnotes(1)(2)

1. Name and Address of Reporting Person^*

RA CAPITAL MANAGEMENT, L.P.

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

RA Capital Healthcare Fund LP

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

RA Capital Nexus Fund III, L.P.

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Kolchinsky Peter

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Shah Rajeev M.

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

Explanation of Responses:

1. RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund III, L.P. (the "Nexus Fund III"). The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, the Nexus Fund III, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein.

2. Held directly by the Fund.

3. Held directly by Nexus Fund III.

4. The Pre-Funded Warrants have no expiration date and are exercisable at any time after the date of issuance. A holder of Pre-Funded Warrants may not exercise the Pre-Funded Warrant if the holder, together with its affiliates, would beneficially own more than 9.99% of the number of shares of common stock outstanding immediately after giving effect to such exercise.

Remarks:

Jake Simson, a Partner of the Adviser, serves on the Issuer's board of directors.

	/s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.	03/02/2026
	/s/ Peter Kolchinsky, Manager of RA Capital Healthcare Fund GP, LLC, the General Partner of RA Capital Healthcare Fund, L.P.	03/02/2026
	/s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund III GP, LLC, the General Partner of RA Capital Nexus Fund III, L.P.	03/02/2026
	/s/ Peter Kolchinsky, individually	03/02/2026
	/s/ Rajeev Shah, individually	03/02/2026
	** Signature of Reporting Person	Date
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FAQ

What insider transactions did BCAX disclose for RA Capital on February 26, 2026?

Bicara Therapeutics disclosed that RA Capital–managed entities bought 2,200,000 Pre-Funded Warrants and 300,000 common shares on February 26, 2026. Both transactions were reported as open-market or private purchases at prices around $16 per security.

What price did RA Capital entities pay for Bicara Therapeutics (BCAX) securities?

RA Capital–managed entities purchased Pre-Funded Warrants at $15.9999 per right and common stock at $16.00 per share. These prices reflect open-market or private purchase transactions reported for February 26, 2026 in the Form 4 filing.

How many Bicara Therapeutics (BCAX) Pre-Funded Warrants did RA Capital funds acquire?

Entities managed by RA Capital Management acquired 2,200,000 Pre-Funded Warrants for Bicara Therapeutics. Each warrant represents a right to buy common stock and was purchased at $15.9999, according to the insider transaction report dated February 26, 2026.

Do the Bicara Therapeutics (BCAX) Pre-Funded Warrants held by RA Capital have an expiration date?

The Pre-Funded Warrants have no expiration date and are exercisable at any time after issuance. However, they cannot be exercised if doing so would cause the holder and affiliates to beneficially own more than 9.99% of Bicara’s outstanding common stock.

How do RA Capital and its principals describe their beneficial ownership of BCAX securities?

RA Capital Management, its general partner, the RA Capital Healthcare Fund, RA Capital Nexus Fund III, Dr. Peter Kolchinsky, and Mr. Rajeev Shah each disclaim beneficial ownership of the reported Bicara securities, except to the extent of their respective pecuniary interests in those holdings.

What indirect holdings of Bicara Therapeutics (BCAX) common stock are reported for RA Capital entities?

The filing shows indirect holdings of Bicara common stock, including 4,603,418 shares following one reported transaction and 2,652,575 shares in another holding line. Footnotes state these are held directly by RA Capital Healthcare Fund LP and RA Capital Nexus Fund III, L.P., respectively.