# EDGAR Filing Document

**Accession Number:** 0001882782
**File Stem:** 0001193125-26-215197
**Filing Date:** 2026-5
**Character Count:** 39499
**Document Hash:** 7f5bd171e4fd188432661899be56acf9
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-215197.hdr.sgml**: 20260511

**ACCESSION NUMBER**: 0001193125-26-215197

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 14

**FILED AS OF DATE**: 20260511

**DATE AS OF CHANGE**: 20260508

**EFFECTIVENESS DATE**: 20260511

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Odyssey Therapeutics, Inc.
- **CENTRAL INDEX KEY:** 0001882782
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 863384382
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-295741
- **FILM NUMBER:** 26960334

**BUSINESS ADDRESS:**
- **STREET 1:** 51 SLEEPER STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210
- **BUSINESS PHONE:** (212) 841-1000

**MAIL ADDRESS:**
- **STREET 1:** 51 SLEEPER STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210

**As filed with the Securities and Exchange Commission on May 8, 2026**

Registration No. 333-

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM S-8**

**REGISTRATION STATEMENT UNDER**

**THE SECURITIES ACT OF 1933**

**ODYSSEY THERAPEUTICS, INC.**

(Exact name of registrant as specified in its charter)

---

| | |
|:---|:---|
| **Delaware** | **86-3384382** |
| (State of incorporation) | (IRS Employer Identification No.) |

---

**51 Sleeper Street** 

**Suite 800**

**Boston, Massachusetts 02210**

**(617) 865-9628**

(Address of principal executive offices / Zip Code)

**Odyssey Therapeutics, Inc.**

**2021 Equity Incentive Plan**

**2026 Long-Term Incentive Plan** 

**2026 Employee Stock Purchase Plan**

(Full title of the plan)

**Gary D. Glick, Ph.D.** 

**President and Chief Executive Officer** 

**Odyssey Therapeutics, Inc.**

**51 Sleeper Street**

**Suite 800**

**Boston, Massachusetts 02210** 

**(617) 865-9628**

(Name, address and telephone number, including area code, of agent for service)

Copies to:

---

| | |
|:---|:---|
| **Brian K. Rosenzweig** <br>**Alicia Zhang**<br>**Covington & Burling LLP**<br>**One International Place, Suite 1020**<br>**Boston, Massachusetts 02110** <br>**(617) 603-8805** | **Jolie M. Siegel**<br>**Executive Vice President, General Counsel and Secretary**<br>**Odyssey Therapeutics, Inc.**<br>**51 Sleeper Street**<br>**Suite 800**<br>**Boston, Massachusetts 02210**<br>**(617) 865-9628** |

---

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

---

| | | | |
|:---|:---|:---|:---|
| Large accelerated filer | ☐ | Accelerated filer | ☐ |
| Non-accelerated filer | ☒ | Smaller reporting company | ☒ |
|  |  | Emerging growth company | ☒ |

---

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

------

**PART I**

**INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS**

The information required by Item 1 and Item 2 of Part I of Form S-8 to be contained in the Section 10(a) prospectus is omitted from this Registration Statement in accordance with Rule 428 under the Securities Act of 1933, as amended (the "Securities Act"), and the introductory note to the instructions to Part I of Form S-8. In accordance with the rules and regulations of the Securities and Exchange Commission (the "Commission") and the instructions to Form S-8, such documents are not being filed with the Commission either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424 under the Securities Act. The Company will deliver the documents containing the information specified in Part I to participants as required by Rule 428(b)(1) under the Securities Act.

**PART II**

**INFORMATION REQUIRED IN THE REGISTRATION STATEMENT**

**Item 3. Incorporation of Documents by Reference.**

The following documents, filed with the Commission pursuant to the Securities Exchange Act of 1934, as amended (the "Exchange Act"), are hereby incorporated by reference in this Registration Statement:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)the Registrant's [<u>prospectus</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526214819/odyssey__form_424b4.htm), dated May 7, 2026, filed with the Commission pursuant to Rule 424(b) under the Securities Act, relating to the Registrant's Registration Statement on Form S-1, as amended (File No. 333- 295141), which contains audited financial statements for the Registrant's latest fiscal year, for which such statements have been filed; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)the description of common stock contained in the Registrant's Registration Statement on [<u>Form 8-A</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526205798/odyssey_-_form_8-a12b.htm) (File No. 001-43270), filed with the Commission on May 5, 2026, under Section 12(b) of the Exchange Act, including any amendments or reports filed for the purpose of updating such description.

All documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, prior to filing a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing such documents, except for the documents, or portions thereof, that are "furnished" (e.g., the portions of those documents set forth under Items 2.02 or 7.01 of Form 8-K or other information "furnished" to the Commission) rather than filed in accordance with the rules of the Commission. Any statement contained in a document incorporated or deemed to be incorporated herein by reference shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document which also is, or is deemed to be, incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

**Item 4. Description of Securities.**

Not applicable.

**Item 5. Interests of Named Experts and Counsel.**

None.

**Item 6. Indemnification of Directors and Officers.**

Section 145 of the Delaware General Corporation Law ("DGCL") authorizes a corporation's board of directors to grant, and authorizes a court to award, indemnity to officers, directors and other corporate agents.

------

The Registrant's Ninth Amended and Restated Certificate of Incorporation (the "Certificate of Incorporation") and Amended and Restated Bylaws (the "Bylaws"), which will become effective immediately prior to the completion of its initial public offering, contain provisions that limit the liability of the Registrant's directors and officers for monetary damages to the fullest extent permitted by law.

Any amendment to, or repeal of, these provisions will not eliminate or reduce the effect of these provisions in respect of any act, omission or claim that occurred or arose prior to that amendment or repeal. If the DGCL is amended to provide for further limitations on the personal liability of directors or officers of corporations, then the personal liability of the Registrant's directors and officers will be further limited to the greatest extent permitted by the DGCL.

The Certificate of Incorporation also provides that the Registrant will indemnify, to the fullest extent permitted by law, each person who is or was made a party or is threatened to be made a party to or is otherwise involved in any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative by reason of the fact that he or she is or was a director or officer of the Registrant or, while a director or officer of the Registrant, is or was serving at the request of the Registrant as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust, other enterprise or nonprofit entity. In addition, the Certificate of Incorporation provides that the Registrant must advance expenses incurred by or on behalf of a director or officer in advance of the final disposition of any action or proceeding, subject to very limited exceptions.

Further, the Registrant has entered into indemnification agreements with each of its directors and executive officers. These indemnification agreements require the Registrant, among other things, to indemnify its directors and executive officers against liabilities that may arise by reason of their status or service. These indemnification agreements also require the Registrant to advance all expenses incurred by the directors and executive officers in investigating or defending any such action, suit or proceeding, subject to certain exceptions. The Registrant believes that these agreements are necessary to attract and retain qualified individuals to serve as directors and executive officers.

The limitation of liability and indemnification provisions that are included in the Certificate of Incorporation, the Bylaws and in the indemnification agreements that the Registrant entered into with its directors and executive officers may discourage stockholders from bringing a lawsuit against its directors and executive officers for breach of their fiduciary duties. They may also reduce the likelihood of derivative litigation against the Registrant's directors and executive officers even though an action, if successful, might benefit the Registrant and other stockholders. Further, a stockholder's investment may be adversely affected to the extent that the Registrant pays the costs of settlement and damage awards against directors and executive officers as required by these indemnification provisions. At present, the Registrant is not aware of any pending litigation or proceeding involving any person who is or was one of its directors, officers, employees or other agents or is or was serving at its request as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, for which indemnification is sought, and the Registrant is not aware of any threatened litigation that may result in claims for indemnification.

The Bylaws provide that the Registrant may purchase and maintain insurance, at its expense, to protect itself and any director, officer, employee or agent of the Registrant or another corporation, partnership, joint venture, trust or other enterprise against any expense, liability or loss, whether or not the Registrant would have the power to indemnify such person against such expense, liability or loss under the DGCL. The Registrant has obtained insurance under which, subject to the limitations of the insurance policies, coverage is provided to the Registrant's directors and executive officers against loss arising from claims made by reason of breach of fiduciary duty or other wrongful acts as a director or executive officer, including claims relating to public securities matters, and to the Registrant with respect to payments that may be made by the Registrant to these directors and executive officers pursuant to the Registrant's indemnification obligations or otherwise as a matter of law.

**Item 7. Exemption from Registration Claimed.**

Not applicable.

------

**Item 8. Exhibits.**

---

| | |
|:---|:---|
| <u>Exhibit No.</u> | <u>Description</u> |
| 3.1 | [<u>Ninth Amended and Restated Certificate of Incorporation (incorporated by reference to Exhibit 3.3 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex3_3.htm) |
| 3.2 | [<u>Amended and Restated Bylaws (incorporated by reference to Exhibit 3.4 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex3_4.htm) |
| 4.1 | [<u>Form of Common Stock Certificate (incorporated by reference to Exhibit 4.1 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex4_1.htm) |
| 4.2 | [<u>Warrant to Purchase Stock, issued to Banc of California (formerly Pacific Western Bank) (incorporated by reference to Exhibit 4.2 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex4_2.htm)<br>|
| 4.3 | [<u>Third Amended and Restated Investors' Rights Agreement, dated June 16, 2025, by and among Odyssey Therapeutics, Inc. and the investors thereto, as amended (incorporated by reference to Exhibit 4.3 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex4_3.htm) |
| 4.4 | [<u>Form of Common Stock Warrant (incorporated by reference to Exhibit 4.4 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex4_4.htm) |
| 5.1\* | [<u>Opinion of Covington & Burling LLP.</u>](odtx-ex5_1.htm) |
| 10.1 <br>| [<u>Odyssey Therapeutics, Inc. 2021 Equity Incentive Plan, as amended, and forms of agreement thereunder (incorporated by reference to Exhibit 10.1 to the Registrant's Registration Statement on Form S-1 (File No. 333-295141), filed with the Commission on April 17, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526161514/odtx-ex10_1.htm)<br>|
| 10.2 | [<u>Odyssey Therapeutics, Inc. 2026 Long-Term Incentive Plan, and forms of agreement thereunder. (incorporated by reference to Exhibit 10.2 to the Registrant's Registration Statement on Form S-1/A (File No. 333-295141), filed with the Commission on May 4, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526202398/odtx-ex10_2.htm) |
| 10.3<br>| [<u>Odyssey Therapeutics, Inc. 2026 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.3 to the Registrant's Registration Statement on Form S-1/A (File No. 333-295141), filed with the Commission on May 4, 2026).</u>](https://www.sec.gov/Archives/edgar/data/1882782/000119312526202398/odtx-ex10_3.htm)<br>|
| 23.1\* | [<u>Consent of Deloitte & Touche LLP, Independent Registered Public Accounting Firm.</u>](odtx-ex23_1.htm) |
| 23.2\* | [<u>Consent of Covington & Burling LLP (included in Exhibit 5.1).</u>](odtx-ex5_1.htm) |
| 24.1\* | [<u>Power of Attorney (included on signature page of this Registration Statement).</u>](#poa) |
| 107\*  | [<u>Filing Fee Table.</u>](odtx-exfiling_fees.htm) |

---

\* Filed herewith.

**Item 9. Undertakings.**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)The undersigned Registrant hereby undertakes:

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1)To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)To include any prospectus required by Section 10(a)(3) of the Securities Act;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)To reflect in the prospectus any facts or events arising after the effective date of this Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this Registration Statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective Registration Statement; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)To include any material information with respect to the plan of distribution not previously disclosed in this Registration Statement or any material change to such information in this Registration Statement.

*Provided, however*, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the information required to be included in a post- effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in this Registration Statement.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2)That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(3)To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in this Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(h)Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

------

**SIGNATURES**

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Boston, Massachusetts, on May 8, 2026.

---

| | |
|:---|:---|
| ODYSSEY THERAPEUTICS, INC. | ODYSSEY THERAPEUTICS, INC. |
| By:  | /s/ Gary D. Glick, Ph.D. |
|  | Name: Gary D. Glick, Ph.D. |
|  | Title: President and Chief Executive Officer |

---

**POWER OF ATTORNEY**

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Gary D. Glick, Ph.D. and Jason Haas, and each of them, as his or her true and lawful attorneys-in-fact and agents, with full power to act separately and full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement and to file the same, with all exhibits thereto, and all other documents in connection therewith, with the Securities and Exchange Commission, granting unto each said attorney-in-fact and agent full power and authority to do and perform each and every act in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or either of them or his or their substitute or substitutes may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/ Gary D. Glick | President, Chief Executive Officer and Director (Principal Executive Officer) | May 8, 2026 |
| Gary D. Glick, Ph.D. | President, Chief Executive Officer and Director (Principal Executive Officer) |  |
| /s/ Jason Haas | Chief Financial Officer (Principal Financial and Accounting Officer) | May 8, 2026 |
| Jason Haas | Chief Financial Officer (Principal Financial and Accounting Officer) |  |
| /s/ Jeffrey M. Leiden | Chairman, Director | May 8, 2026 |
| Jeffrey M. Leiden, M.D., Ph.D. |  |  |
| /s/ Shelley Chu | Director | May 8, 2026 |
| Shelley Chu, M.D., Ph.D. |  |  |
| /s/ Paulina Hill | Director | May 8, 2026 |
| Paulina Hill, Ph.D. |  |  |
| /s/ Nan Li | Director | May 8, 2026 |
| Nan Li |  |  |
| /s/ Carolyn Ng | Director | May 8, 2026 |
| Carolyn Ng, Ph.D. |  |  |
| /s/ Ian F. Smith | Director | May 8, 2026 |
| Ian F. Smith |  |  |

---

------

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/ Valerie Odegard | Director | May 8, 2026 |
| Valerie Odegard, Ph.D. |  |  |
| /s/ Ksenija Pavletic | Director | May 8, 2026 |
| Ksenija Pavletic |  |  |
| /s/ Nia Tatsis | Director | May 8, 2026 |
| Nia Tatsis, Ph.D. |  |  |
| /s/ Timothy P. Walbert | Director | May 8, 2026 |
| Timothy P. Walbert |  |  |

---

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## Exhibit 5.1

---

| | |
|:---|:---|
| ![img202443603_0.jpg](img202443603_0.jpg) | Covington & Burling LLP |
| BEIJING BOSTON BRUSSELS DUBAI FRANKFURT | 30 Hudson Yards |
| JOHANNESBURG LONDON LOS ANGELES NEW YORK | New York, NY 10001-2170 |
| PALO ALTO SAN FRANCISCO SEOUL SHANGHAI WASHINGTON | T +1 212 841 1000 |

---

**Exhibit 5.1**

May 8, 2026

Odyssey Therapeutics, Inc.

51 Sleeper Street, Suite 800

Boston, Massachusetts 02210

Ladies and Gentlemen:

We have acted as counsel to Odyssey Therapeutics, Inc., a Delaware corporation (the "*Company*"), and are rendering this opinion in connection with the registration by the Company under the Securities Act of 1933 (the "*Securities Act*") of the offer and sale of up to 11,190,239 shares of the Company's common stock (the "*Common Stock*"), par value $0.0001 per share (the "*Shares*"), consisting of (i) 4,441,463 Shares issuable pursuant to the exercise of outstanding options granted under the Odyssey Therapeutics, Inc. 2021 Equity Incentive Plan (the "*2021 Plan*"), (ii) 3,431,900 Shares issuable pursuant to the exercise of outstanding options granted under the Odyssey Therapeutics, Inc. 2026 Long-Term Incentive Plan (the "*2026 Plan*"), (iii) 2,800,476 Shares reserved for future issuance under the 2026 Plan, and (iv) 516,400 Shares reserved for future issuance under the Odyssey Therapeutics, Inc. 2026 Employee Stock Purchase Plan (the "*ESPP*" and together with the 2021 Plan and the 2026 Plan, the "*Plans*") pursuant to the registration statement on Form S-8 filed with the United States Securities and Exchange Commission on the date hereof (the "*Registration Statement*").

We have reviewed:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)the Registration Statement;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)the Plans;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)the Company's Ninth Amended and Restated Certificate of Incorporation, as currently in effect; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv)the Company's Amended and Restated Bylaws, as currently in effect.

We have also reviewed such corporate records, certificates and other documents, and such questions of law, as we have deemed necessary or appropriate for the purposes of this opinion. We have assumed that all signatures are genuine, that all documents submitted to us as originals are authentic and that all copies of documents submitted to us conform to the originals. We have also assumed that the Shares will be duly registered on the books of the transfer agent and registrar of the Common Stock and that the Company will comply with applicable notice requirements regarding uncertificated shares provided under the Delaware General Corporation Law (the "*DGCL*"). We have assumed further that, except as to legal conclusions expressly set forth in this opinion, the information and representations and warranties contained in the agreements, instruments, records, certificates and other documents we

------

reviewed were true, accurate and complete as of their stated date and are true, accurate and complete as of the date of this letter.

We have relied as to certain matters on information obtained from public officials, officers of the Company, and other sources believed by us to be responsible.

Based upon the foregoing, we are of the opinion that the Shares have been duly authorized and, assuming that individual issuances under the Plan are duly authorized by all necessary corporate action of the Company, when issued in accordance with the terms of the Plans, and any awards duly adopted thereunder and in accordance therewith, will be validly issued, fully paid and nonassessable.

We are members of the bar of the State of New York. We do not express any opinion herein on any laws other than the DGCL.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.

---

| |
|:---|
| Very truly yours, |
| /s/ Covington & Burling LLP |

---

------

## Exhibit 23.1

# Exhibit 23.1

# CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the incorporation by reference in this registration statement on Form S-8 of our report dated March 16, 2026 (May 4, 2026, as to the effects of the reverse stock split discussed in Note 19), relating to the financial statements of Odyssey Therapeutics, Inc., appearing in registration statement No. 333-295141 on Form S-1 of Odyssey Therapeutics, Inc.

/s/ Deloitte & Touche LLP

Boston, Massachusetts

May 8, 2026

------

## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

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| |
|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **S-8**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Odyssey Therapeutics, Inc.**  |

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| | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Type**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Class Title**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Calculation Rule**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount Registered**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Proposed Maximum Offering Price Per Unit**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Maximum Aggregate Offering Price**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Rate**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount of Registration Fee**  |
| 1 | Equity | Common stock, $0.0001 par value per share, issuable pursuant to the exercise of outstanding options granted under the Odyssey Therapeutics, Inc. 2021 Equity Incentive Plan | Other | 4441463 | $4.66 | $20697217.58 | 0.0001381 | $2858.29 |
| 2 | Equity | Common stock, $0.0001 par value per share, issuable pursuant to the exercise of outstanding options granted under the Odyssey Therapeutics, Inc. 2026 Long-Term Incentive Plan | Other | 3431900 | $18.00 | $61774200.00 | 0.0001381 | $8531.02 |
| 3 | Equity | Common stock, $0.0001 par value per share, reserved for future issuance under the Odyssey Therapeutics, Inc. 2026 Long-Term Incentive Plan | Other | 2800476 | $18.00 | $50408568.00 | 0.0001381 | $6961.42 |
| 4 | Equity | Common stock, $0.0001 par value per share, reserved for future issuance under the Odyssey Therapeutics, Inc. 2026 Employee Stock Purchase Plan | Other | 516400 | $18.00 | $9295200.00 | 0.0001381 | $1283.67 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $142175185.58  |  | $19634.40  |
| Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
| Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $19634.40  |

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Offering Note** <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>1</sup> (A) Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement also registers any additional shares of common stock, $0.0001 par value per share ("Common Stock"), of Odyssey Therapeutics, Inc. (the "Registrant") that become issuable under the Registrant's 2021 Equity Incentive Plan (the "2021 Plan"), the Registrant's 2026 Long-Term Incentive Plan (the "2026 Plan") and the Registrant's 2026 Employee Stock Purchase Plan (the "2026 ESPP") by reason of any stock dividend, stock split, recapitalization or other similar transaction. (B) Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h) of the Securities Act. The proposed maximum aggregate offering price per share and proposed maximum aggregate offering price for the 4,441,463 shares of Common Stock issuable pursuant to the exercise of outstanding options granted under the 2021 Plan are calculated using the weighted-average exercise price of $4.66 per share for such stock options. (C) Represents shares of Common Stock issuable pursuant to the exercise of outstanding options granted under the 2021 Plan. No additional stock awards will be granted under the 2021 Plan. The shares of Common Stock reserved for issuance pursuant to such stock options will become available for issuance under the 2026 Plan to the extent any such shares are forfeited, canceled, reacquired by the Registrant prior to vesting, expired (whether voluntarily or involuntarily), settled in cash or otherwise satisfied without the issuance of shares, withheld upon exercise of an option or settlement of an award to cover the exercise price or tax withholding, surrendered pursuant to an exchange or otherwise terminated (other than by exercise). See footnote 3(C) below.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>2</sup> (A) Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h) of the Securities Act. The proposed maximum aggregate offering price per share and proposed maximum aggregate offering price for the 3,431,900 shares of Common Stock issuable pursuant to the exercise of outstanding options granted under the 2026 Plan are calculated using the weighted-average exercise price of $18.00 per share for such stock options, which is equal to the initial public offering price for shares of the Common Stock (the "IPO Price") as set forth in the Registrant's Registration Statement on Form S-1 (File No. 333-295141), as amended, that was declared effective on May 7, 2026. (B) Represents shares of Common Stock issuable pursuant to the exercise of outstanding options granted under the 2026 Plan.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>3</sup> (A) Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(c) and Rule 457(h) of the Securities Act. The proposed maximum aggregate offering price per share and proposed maximum aggregate offering price are calculated on the basis of the IPO Price. (B) Represents 2,800,476 shares of Common Stock reserved for future issuance under the 2026 Plan. The number of shares of Common Stock reserved for future issuance under the 2026 Plan will automatically increase on January 1 of each year, beginning on January 1, 2027 and continuing through January 1, 2036, in an amount equal to 5% of the total number of shares of the Registrant's capital stock (including shares underlying unexercised pre-funded warrants with an exercise price per share of $0.01 or less) outstanding on December 31 of the preceding year; provided, however, that the Registrant's board of directors may act prior to January 1 of a given year to provide that the increase for such year will be a lesser number of shares of Common Stock. This explanation is provided for information purposes only. The issuance of such additional shares is not being registered on this Registration Statement. (C) To the extent outstanding awards under the 2026 Plan are forfeited, canceled, reacquired by the Registrant prior to vesting, expired (whether voluntarily or involuntarily), settled in cash or otherwise satisfied without the issuance of shares, withheld upon exercise of an option or settlement of an award to cover the exercise price or tax withholding, surrendered pursuant to an exchange or otherwise terminated (other than by exercise), they will become or again be available under the 2026 Plan. See footnote 1(C) above.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>4</sup> (A) Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(c) and Rule 457(h) of the Securities Act. The proposed maximum aggregate offering price per share and proposed maximum aggregate offering price are calculated on the basis of the IPO Price, multiplied by 85%, which is the percentage of the price per share applicable to purchases under the 2026 ESPP. (B) Represents 516,400 shares of Common Stock reserved for future issuance under the 2026 ESPP. The number of shares of Common Stock reserved for issuance under the 2026 ESPP will automatically increase on January 1 of each year, beginning on January 1, 2027 and continuing through January 1, 2036, in an amount equal to the lesser of (i) 1% of the total number of shares of the Registrant's capital stock outstanding on December 31 of the immediately preceding year and (ii) 1,032,801 shares of Common Stock, unless Registrant's board of directors acts prior to the first day of any calendar year to provide that there will be no January 1 increase in the share reserve for such calendar year or that the increase for such calendar year will be a lesser number of shares of Common Stock. This explanation is provided for information purposes only. The issuance of such additional shares is not being registered on this Registration Statement.

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| **Rule 457(p)** |
| Fee Offset Claims |
| Fee Offset Sources |

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