RA Capital funds add 369,000 Mineralys (NASDAQ: MLYS) shares

Rhea-AI Filing Summary

RA Capital–managed funds reported open-market purchases of Mineralys Therapeutics stock. On March 27, 2026, they bought 310,700 shares of common stock at a weighted average price of $23.67 per share. On March 30, 2026, they added 58,300 shares at a weighted average price of $24.16 per share.

Shares are held indirectly through RA Capital Healthcare Fund LP and RA Capital Nexus Fund III, L.P., with RA Capital Management, L.P. acting as investment manager. After these transactions, one fund held 5,825,521 shares as of March 30, 2026, while another related fund held 1,867,229 shares as of March 27, 2026.

Insider Trade Summary

Net Buyer: 369,000 shares ($8,762,797)

Net Buy 3 txns

Insider RA CAPITAL MANAGEMENT, L.P., RA Capital Healthcare Fund LP, RA Capital Nexus Fund III, L.P., Kolchinsky Peter, Shah Rajeev M.

Role Director | Director | Director | Director | Director

Bought 369,000 shs ($8.76M)

Type	Security	Shares	Price	Value
Purchase	Common Stock	58,300	$24.16	$1.41M
Purchase	Common Stock	310,700	$23.67	$7.35M
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 5,825,521 shares (Indirect, See footnotes)

Footnotes (1)

1. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $23.31 to $24.01 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote. Held directly by the RA Capital Healthcare Fund, L.P. (the "Fund"). RA Capital Management, L.P. (the "Adviser") is the investment manager for 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. The Adviser, the Adviser GP, the Fund, the Nexus Fund III, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $23.88 to $24.39 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote. Held directly by Nexus Fund III.

Key Figures

Total shares purchased: 369,000 shares March 27 purchase size: 310,700 shares March 27 weighted average price: $23.67 per share +4 more

7 metrics

Total shares purchased 369,000 shares Open-market common stock buys on March 27 and March 30, 2026

March 27 purchase size 310,700 shares Open-market common stock purchase on March 27, 2026

March 27 weighted average price $23.67 per share Weighted average price for March 27, 2026 purchase

March 30 purchase size 58,300 shares Open-market common stock purchase on March 30, 2026

March 30 weighted average price $24.16 per share Weighted average price for March 30, 2026 purchase

Fund holding after March 30 5,825,521 shares Indirect common stock holding following March 30, 2026 purchase

Nexus Fund III holding 1,867,229 shares Indirect common stock holding as of March 27, 2026

Key Terms

weighted average price, open-market purchase, beneficial ownership, pecuniary interest, +1 more

5 terms

weighted average price financial

"The price reported in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

open-market purchase financial

"transaction_action": "open-market purchase""

An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.

beneficial ownership financial

"disclaim beneficial ownership of any of the reported securities"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

pecuniary interest financial

"except to the extent of their pecuniary interest therein"

indirect ownership financial

""ownership_type": "indirect""

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^*

RA CAPITAL MANAGEMENT, L.P.

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Mineralys Therapeutics, Inc. [ MLYS ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/27/2026

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

	Form filed by One Reporting Person
X	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	03/27/2026		P		310,700	A	$23.67(1)	5,767,221	I	See footnotes(2)(3)
Common Stock	03/30/2026		P		58,300	A	$24.16(4)	5,825,521	I	See footnotes(2)(3)
Common Stock								1,867,229	I	See footnotes(3)(5)

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

1. Name and Address of Reporting Person^*

RA CAPITAL MANAGEMENT, L.P.

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

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^*

RA Capital Healthcare Fund LP

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

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^*

RA Capital Nexus Fund III, L.P.

(Last) (First) (Middle)

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

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 MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

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^*

Shah Rajeev M.

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $23.31 to $24.01 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

2. Held directly by the RA Capital Healthcare Fund, L.P. (the "Fund").

3. RA Capital Management, L.P. (the "Adviser") is the investment manager for 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. The Adviser, the Adviser GP, the Fund, the Nexus Fund III, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

4. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $23.88 to $24.39 inclusive. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

5. Held directly by Nexus Fund III.

Remarks:

Dr. Derek DiRocco, a Partner of the Adviser, serves on the Issuer's board of directors.

	/s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.	03/31/2026
	/s/ Peter Kolchinsky, Manager of RA Capital Healthcare Fund GP, LLC the General Partner of RA Capital Healthcare Fund, L.P.	03/31/2026
	/s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund III GP, LLC the General Partner of RA Capital Nexus Fund III, L.P.	03/31/2026
	/s/ Peter Kolchinsky, individually	03/31/2026
	/s/ Rajeev Shah, individually	03/31/2026
	** 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 buying did RA Capital report for MLYS on this Form 4?

RA Capital–managed funds reported buying a combined 369,000 shares of Mineralys Therapeutics common stock. They purchased 310,700 shares on March 27, 2026 and 58,300 shares on March 30, 2026 in open-market transactions at weighted average prices in the mid-$20 range.

At what prices did RA Capital funds buy Mineralys Therapeutics (MLYS) shares?

The reported purchases occurred at weighted average prices of $23.67 per share on March 27, 2026 and $24.16 per share on March 30, 2026. Footnotes explain these averages reflect multiple trades within narrow price ranges on each day.

How many Mineralys Therapeutics (MLYS) shares did RA Capital funds hold after these trades?

Following the March 30, 2026 purchase, one RA Capital–managed fund held 5,825,521 shares of Mineralys common stock. A related Nexus fund is reported holding 1,867,229 shares as of March 27, 2026, both positions held indirectly through investment vehicles.

Who actually holds the MLYS shares reported in this RA Capital Form 4?

The shares are held directly by RA Capital Healthcare Fund LP and RA Capital Nexus Fund III, L.P. RA Capital Management, L.P. serves as investment manager, and related entities and individuals disclaim beneficial ownership beyond their pecuniary interest in these funds.

Were the Mineralys Therapeutics (MLYS) insider trades open-market purchases?

Yes. The filing classifies both transactions with code P, described as an open-market or private purchase of common stock. Footnotes add that reported prices are weighted averages based on multiple executions within specified intraday price ranges.