Fund tied to Kailera Therapeutics (KLRA) director buys 8.4M shares

Rhea-AI Filing Summary

BCPE Perseus Investor, LP, an entity associated with Kailera Therapeutics, Inc. director and 10% owner Andrew T. Kaplan, bought 8,398,438 shares of Kailera Therapeutics common stock at $16.00 per share on April 20, 2026 in an open-market transaction reported as indirect ownership.

On the same date, 17,857,143 shares of Series B Preferred Stock held by BCPE Perseus automatically converted into an equal number of common shares on a 1:1 basis upon the closing of Kailera’s initial public offering. Following these transactions, BCPE Perseus is reported as indirectly holding 26,255,581 common shares, while Kaplan also received a direct grant of stock options for 38,300 shares at a $16.00 exercise price that vest on April 16, 2027. Kaplan disclaims beneficial ownership of BCPE Perseus’ holdings except to the extent of his pecuniary interest.

Insights

Insider transactions analyst

PE fund linked to Kailera director makes large buy and IPO-driven conversion.

BCPE Perseus Investor, LP, an investment vehicle associated with Andrew T. Kaplan through Bain Capital Investors, bought 8,398,438 common shares of Kailera Therapeutics at $16.00 per share on April 20, 2026. This is an open-market or private purchase and is reported as indirect ownership.

Separately, 17,857,143 shares of Series B Preferred Stock held by BCPE Perseus automatically converted into common stock on a 1:1 basis upon Kailera’s initial public offering, eliminating that preferred position and increasing the reported indirect common stake to 26,255,581 shares. These moves reflect a shift from preferred to common equity rather than a sale.

Kaplan also received a direct grant of stock options over 38,300 common shares with a $16.00 exercise price, vesting fully on April 16, 2027, which is standard equity compensation. Footnotes state Kaplan may be deemed to share voting and dispositive power over BCPE Perseus’ holdings but disclaims beneficial ownership beyond his pecuniary interest.

Insider Trade Summary

Net Buyer: 8,398,438 shares ($134,375,008)

Net Buy 4 txns

Insider Kaplan Andrew T.

Role null

Bought 8,398,438 shs ($134.38M)

Type	Security	Shares	Price	Value
Conversion	Series B Preferred Stock	17,857,143	$0.00	--
Conversion	Common Stock	17,857,143	$0.00	--
Purchase	Common Stock	8,398,438	$16.00	$134.38M
Grant/Award	Stock Option (right to buy)	38,300	$0.00	--

Holdings After Transaction: Series B Preferred Stock — 0 shares (Indirect, See footnotes); Common Stock — 17,857,143 shares (Indirect, See footnotes); Stock Option (right to buy) — 38,300 shares (Direct, null)

Footnotes (1)

1. Each share of the Issuer's Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date. The options vest and become exercisable as to 100% of the underlying shares on April 16, 2027, subject to Mr. Kaplan's continued service through each such vesting date. Represents securities held directly by BCPE Perseus Investor, LP ("BCPE Perseus"). Mr. Kaplan is a Partner of Bain Capital Investors, LLC ("BCI"). BCI is the ultimate general partner of BCPE Perseus. As a result, Mr. Kaplan may be deemed to share voting and dispositive power with respect to the securities held by BCPE Perseus. Mr. Kaplan disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

Key Figures

Open-market purchase: 8,398,438 shares at $16.00 Preferred-to-common conversion: 17,857,143 shares 1:1 Indirect common holdings: 26,255,581 shares +3 more

6 metrics

Open-market purchase 8,398,438 shares at $16.00 Common Stock bought on April 20, 2026 by BCPE Perseus (indirect)

Preferred-to-common conversion 17,857,143 shares 1:1 Series B Preferred converted into common upon IPO closing

Indirect common holdings 26,255,581 shares Common Stock indirectly held after transactions

Stock option grant 38,300 options at $16.00 Options over common stock granted April 16, 2026

Option vesting date April 16, 2027 Options vest 100% on this date, subject to service

Series B Preferred position after conversion 0 shares Series B Preferred Stock holdings following automatic conversion

Key Terms

Series B Preferred Stock, initial public offering, Stock Option (right to buy), conversion of derivative security, +1 more

5 terms

Series B Preferred Stock financial

"Each share of the Issuer's Series B Preferred Stock automatically converted into shares..."

Series B preferred stock is a type of ownership share issued by a company that offers certain advantages over common stock, such as priority in receiving dividends or assets if the company is sold or liquidated. It is typically issued after an initial round of funding, making it a way for investors to support a company's growth while gaining some protections and benefits. This stock matters to investors because it often provides a more secure investment position with potential for future growth.

initial public offering financial

"automatically converted into shares of the Issuer's Common Stock ... upon the closing of the Issuer's initial public offering."

An initial public offering (IPO) is when a private company first sells its shares to the public and becomes a stock-listed company. It matters because it allows the company to raise money from a wide range of investors, helping it grow, while giving early shareholders a way to sell some of their ownership.

Stock Option (right to buy) financial

"Stock Option (right to buy) ... underlying security title: Common Stock, underlying security shares: 38300.0000"

conversion of derivative security financial

"transaction_action: derivative conversion, transaction_code_description: Conversion of derivative security"

pecuniary interest financial

"Mr. Kaplan disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."

Form 4 Insider Transactions: What Each Field Means →

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
Estimated average burden
hours per response:			0.5

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^*

Kaplan Andrew T.

(Last) (First) (Middle)

C/O BAIN CAPITAL INVESTORS LLC

200 CLARENDON STREET

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Kailera Therapeutics, Inc. [ KLRA ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/16/2026

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

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

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

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	04/20/2026		C		17,857,143	A	(1)	17,857,143	I	See footnotes(3)(4)
Common Stock	04/20/2026		P		8,398,438	A	$16	26,255,581	I	See footnotes(3)(4)

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
Series B Preferred Stock	(1)	04/20/2026		C			17,857,143	(1)	(1)	Common Stock	17,857,143	$0	0	I	See footnotes(3)(4)
Stock Option (right to buy)	$16	04/16/2026		A		38,300		(2)	04/16/2036	Common Stock	38,300	$0	38,300	D

Explanation of Responses:

1. Each share of the Issuer's Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

2. The options vest and become exercisable as to 100% of the underlying shares on April 16, 2027, subject to Mr. Kaplan's continued service through each such vesting date.

3. Represents securities held directly by BCPE Perseus Investor, LP ("BCPE Perseus").

4. Mr. Kaplan is a Partner of Bain Capital Investors, LLC ("BCI"). BCI is the ultimate general partner of BCPE Perseus. As a result, Mr. Kaplan may be deemed to share voting and dispositive power with respect to the securities held by BCPE Perseus. Mr. Kaplan disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

	/s/ Andrew Kaplan	04/20/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transactions were reported for Kailera Therapeutics (KLRA)?

The filing shows BCPE Perseus Investor, LP bought 8,398,438 Kailera Therapeutics common shares at $16.00 and converted 17,857,143 Series B Preferred shares into common stock, plus a separate grant of 38,300 stock options to director Andrew T. Kaplan.

Who actually bought the 8,398,438 KLRA shares and at what price?

BCPE Perseus Investor, LP, an entity associated with Andrew T. Kaplan, purchased 8,398,438 shares of Kailera Therapeutics common stock at $16.00 per share on April 20, 2026, in an open‑market or private transaction reported as indirect ownership.

What happened to the Series B Preferred Stock of Kailera Therapeutics (KLRA)?

BCPE Perseus Investor, LP’s 17,857,143 shares of Series B Preferred Stock automatically converted into 17,857,143 Kailera Therapeutics common shares on a 1:1 basis upon closing of the company’s initial public offering, eliminating that preferred position with no stated expiration date.

How many Kailera Therapeutics (KLRA) shares are indirectly held after these transactions?

After the April 20, 2026 transactions, the Form 4 reports that 26,255,581 shares of Kailera Therapeutics common stock are indirectly held through BCPE Perseus Investor, LP, reflecting both the large open‑market purchase and the automatic conversion of Series B Preferred shares into common stock.

What stock options did Andrew T. Kaplan receive from Kailera Therapeutics (KLRA)?

Andrew T. Kaplan received a grant of stock options covering 38,300 shares of Kailera Therapeutics common stock with a $16.00 exercise price. These options vest and become exercisable as to 100% of the underlying shares on April 16, 2027, subject to his continued service.

Does Andrew T. Kaplan directly own the KLRA shares held by BCPE Perseus?

The filing explains that the Kailera Therapeutics securities are held by BCPE Perseus Investor, LP. Kaplan, a partner of Bain Capital Investors, may be deemed to share voting and dispositive power but disclaims beneficial ownership except for his pecuniary interest in those holdings.