# EDGAR Filing Document

**Accession Number:** 0001808865
**File Stem:** 0001104659-25-056379
**Filing Date:** 2025-6
**Character Count:** 14941
**Document Hash:** 59b01095346143f6ce92081c9e812b0a
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-056379.hdr.sgml**: 20250604

**ACCESSION NUMBER**: 0001104659-25-056379

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13G

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20250604

**DATE AS OF CHANGE**: 20250604

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** iTeos Therapeutics, Inc.
- **CENTRAL INDEX KEY:** 0001808865
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-91596
- **FILM NUMBER:** 251023028

**BUSINESS ADDRESS:**
- **STREET 1:** 321 ARSENAL STREET
- **STREET 2:** BLDG 312, FLOOR 3, SUITE 301
- **CITY:** WATERTOWN
- **STATE:** MA
- **ZIP:** 02472
- **BUSINESS PHONE:** 857-204-4583

**MAIL ADDRESS:**
- **STREET 1:** 321 ARSENAL STREET
- **STREET 2:** BLDG 312, FLOOR 3, SUITE 301
- **CITY:** WATERTOWN
- **STATE:** MA
- **ZIP:** 02472
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Ridgeback Capital Investments L.P.
- **CENTRAL INDEX KEY:** 0001423994

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G

**BUSINESS ADDRESS:**
- **STREET 1:** 30 STAR ISLAND DRIVE
- **CITY:** MIAMI BEACH
- **STATE:** FL
- **ZIP:** 33139
- **BUSINESS PHONE:** 212-808-7729

**MAIL ADDRESS:**
- **STREET 1:** 30 STAR ISLAND DRIVE
- **CITY:** MIAMI BEACH
- **STATE:** FL
- **ZIP:** 33139

## Exhibit 99.1

Exhibit 99.1

JOINT FILING AGREEMENT

The undersigned hereby agree that statements on Schedules 13G and/or 13D and Forms 3, 4 and 5 with respect to the securities of iTeos Therapeutics, Inc. and any amendments thereto signed by each of the undersigned shall be filed on behalf of each of the undersigned pursuant to and in accordance with the provisions of Rule 13d-1(k) promulgated under the Securities Exchange Act of 1934, as amended. The undersigned hereby further agree that this Joint Filing Agreement may be included as an exhibit to such statements or amendments. This Joint Filing Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

Dated: June 4, 2025

---

| | |
|:---|:---|
|  | **Ridgeback Capital Investments L.P.** |
| By: | Ridgeback Capital Investments LLC,<br> Its General Partner |
| By: | /s/ Nicole Venezia |
|  | Name: Nicole Venezia |
|  | Title: General Counsel |
|  | **Ridgeback Capital Investments LLC** |
| By: | /s/ Nicole Venezia |
|  | Name: Nicole Venezia |
|  | Title: General Counsel |
|  | **Ridgeback Capital Management LLC** |
| By: | /s/ Nicole Venezia |
|  | Name: Nicole Venezia |
|  | Title: General Counsel |

---

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

## SCHEDULE 13G

### Under the Securities Exchange Act of 1934

**Issuer:** iTeos Therapeutics, Inc.

**Title of Class of Securities:** Common stock, par value $0.001 per share

**CUSIP Number:** 46565G104

**Date of Event Which Requires Filing of this Statement:** 05/28/2025

**Check the appropriate box to designate the rule pursuant to which this Schedule is filed:**

- [ ] Rule 13d-1(b)

- [x] Rule 13d-1(c)

- [ ] Rule 13d-1(d)

---

| 1. | Names of Reporting Persons<br>Ridgeback Capital Investments L.P. | Names of Reporting Persons<br>Ridgeback Capital Investments L.P. |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>DE | Citizenship or Place of Organization<br>DE |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>1442959.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>1442959.00 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>1442959.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>1442959.00 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>3.8% | Percent of Class Represented by Amount in Row (9)<br>3.8% |
| 12. | Type of Reporting Person (See Instructions)<br>OO | Type of Reporting Person (See Instructions)<br>OO |

---

| 1. | Names of Reporting Persons<br>Ridgeback Capital Investments LLC | Names of Reporting Persons<br>Ridgeback Capital Investments LLC |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>DE | Citizenship or Place of Organization<br>DE |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>1442959.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>1442959.00 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>1442959.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>1442959.00 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>3.8% | Percent of Class Represented by Amount in Row (9)<br>3.8% |
| 12. | Type of Reporting Person (See Instructions)<br>OO | Type of Reporting Person (See Instructions)<br>OO |

---

| 1. | Names of Reporting Persons<br>Ridgeback Capital Management LLC | Names of Reporting Persons<br>Ridgeback Capital Management LLC |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>DE | Citizenship or Place of Organization<br>DE |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>1442959.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>1442959.00 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>1442959.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>1442959.00 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>3.8% | Percent of Class Represented by Amount in Row (9)<br>3.8% |
| 12. | Type of Reporting Person (See Instructions)<br>OO | Type of Reporting Person (See Instructions)<br>OO |

---

**Item 1(a). Name of Issuer:**
iTeos Therapeutics, Inc.

**Item 1(b). Address of Issuer's Principal Executive Offices:**
321 Arsenal Street Bldg. 312, Floor 3, Suite 301 Watertown, MA, 02472

**Item 2(a). Name of Person Filing:**
This statement is filed on behalf of the following persons with respect to shares of common stock of the Company acquired by them (the "Shares"):

(i)     Ridgeback Capital Investments L.P., Delaware limited partnership ("RCILP"), with respect to Shares beneficially owned by it;

(ii)    Ridgeback Capital Investments LLC, a Delaware limited liability company ("RCI"), with respect to Shares beneficially owned by it; and

(iii)   Ridgeback Capital Management LLC, a Delaware limited liability company ("RCM"), with respect to Shares beneficially owned by it.

The foregoing persons are hereinafter referred to collectively as the "Reporting Persons."  Any disclosures herein with respect to persons other than the Reporting Persons are made on information and belief after making inquiry to the appropriate party.

RCM and RCI do not own any Shares directly.  RCI is the general partner of RCILP.  Pursuant to an investment management agreement, RCM maintains investment and voting power with respect to the securities held or controlled by RCI.  Wayne Holman, an individual, controls RCM. By reason of the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, RCM and RCI may be deemed to own beneficially all of the Shares (constituting approximately 3.8% of the shares outstanding).  Each of RCM and RCI disclaim beneficial ownership of any of the securities covered by this statement, except to the extent of any pecuniary interest therein.

**Item 2(b). Address of Principal Business Office:**
30 Star Island Drive, Miami, FL, 33139

**Item 2(c). Citizenship:**
RCILP is a Delaware limited partnership.  RCI is a Delaware limited liability company.  RCM is a Delaware limited liability company.

**Item 2(d). Title of Class of Securities:**
Common stock, par value $0.001 per share

**Item 2(e). CUSIP Number:**
46565G104

**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:**

Ridgeback Capital Investments L.P.: 1,442,959
Ridgeback Capital Investments LLC: 1,442,959
Ridgeback Capital Management LLC: 1,442,959

**(b) Percent of class:**

Ridgeback Capital Investments L.P.: 3.8%
Ridgeback Capital Investments LLC: 3.8%
Ridgeback Capital Management LLC: 3.8%

**(c) Number of shares as to which the person has:**

**(i) Sole power to vote or to direct the vote:**

Ridgeback Capital Investments L.P.: -0-
Ridgeback Capital Investments LLC: -0-
Ridgeback Capital Management LLC: -0-

**(ii) Shared power to vote or to direct the vote:**

Ridgeback Capital Investments L.P.: 1,442,959
Ridgeback Capital Investments LLC: 1,442,959
Ridgeback Capital Management LLC: 1,442,959

**(iii) Sole power to dispose or to direct the disposition of:**

Ridgeback Capital Investments L.P.: -0-
Ridgeback Capital Investments LLC: -0-
Ridgeback Capital Management LLC: -0-

**(iv) Shared power to dispose or to direct the disposition of:**

Ridgeback Capital Investments L.P.: 1,442,959
Ridgeback Capital Investments LLC: 1,442,959
Ridgeback Capital Management LLC: 1,442,959
The percentages used herein are calculated based upon 38,273,795 shares of common stock outstanding as of April 22,2025, as reported by the Company in its Quarterly Report on Form 10-Q filed with the SEC on April 28. 2025. As of May 28,2025, the Reporting Persons beneficially owned 1,942,959 shares, or 5.1% of the outstanding shares. As of the close of business on June 4, 2025, the Reporting Persons beneficially owned 1,442,959 shares, or 3.8% of the outstanding shares.

**Item 5. Ownership of Five Percent or Less of a Class.**

[ ] If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following.

**Item 6. Ownership of More than 5 Percent on Behalf of Another Person.**

Not Applicable

**Item 7. Identification and Classification of the Subsidiary**

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. Certification:**

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above 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.

**Ridgeback Capital Investments L.P.**

**Date:** 06/04/2025

**By:** /s/ Nicole Venezia

**Name & Title:** Nicole Venezia/General Counsel

**Ridgeback Capital Investments LLC**

**Date:** 06/04/2025

**By:** /s/ Nicole Venezia

**Name & Title:** Nicole Venezia/General Counsel

**Ridgeback Capital Management LLC**

**Date:** 06/04/2025

**By:** /s/ Nicole Venezia

**Name & Title:** Nicole Venezia/General Counsel