# EDGAR Filing Document

**Accession Number:** 0001621227
**File Stem:** 0001104659-26-046473
**Filing Date:** 2026-4
**Character Count:** 3697
**Document Hash:** f66c73e2ce916827900b13f526a64abc
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-046473.hdr.sgml**: 20260422

**ACCESSION NUMBER**: 0001104659-26-046473

**CONFORMED SUBMISSION TYPE**: RW

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260422

**DATE AS OF CHANGE**: 20260422

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Adaptimmune Therapeutics PLC
- **CENTRAL INDEX KEY:** 0001621227
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** X0
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** RW

**SEC ACT:**
- **SEC FILE NUMBER:** 333-286639
- **FILM NUMBER:** 26881596

**BUSINESS ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** 60 JUBILEE AVENUE
- **STREET 2:** MILTON PARK
- **CITY:** ABINGDON, OXFORDSHIRE
- **PROVINCE COUNTRY:** X0
- **BUSINESS PHONE:** 44 1235 430000

**MAIL ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** 60 JUBILEE AVENUE
- **STREET 2:** MILTON PARK
- **CITY:** ABINGDON, OXFORDSHIRE
- **PROVINCE COUNTRY:** X0

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Adaptimmune Ltd
- **DATE OF NAME CHANGE:** 20141001

**Adaptimmune Therapeutics plc**

The Innovation Centre<br> 99 Park Drive<br> Milton Park<br> Abingdon, Oxfordshire OX14 4RY

United Kingdom

April 22, 2026

**<u>VIA EDGAR</u>**

United States Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

Re: Adaptimmune Therapeutics plc Registration Statement on Form S-3 File No. 333-286639

Ladies and Gentlemen:

Pursuant to Rule 477 under the Securities Act of 1933, as amended (the "Securities Act"), Adaptimmune Therapeutics plc (the "Company") respectfully requests the immediate withdrawal of the Company's Registration Statement on Form S-3 (File No. 333-286639) initially filed with the Securities and Exchange Commission (the "Commission") on April 18, 2025, together with all exhibits thereto (the "Registration Statement"), with such request to be approved effective as of the date hereof or at the earliest practical date thereafter. The Company has determined to withdraw the Registration Statement in light of the Company's voluntary delisting process with respect to its American Depositary Shares ("ADSs") from The Nasdaq Capital Market and the Company's filing of a Form 25 on October 28, 2025 and a Form 15 on November 13, 2025 to effect such delisting and to deregister the ADSs.

The Registration Statement has not been declared effective by the Commission, and no securities have been issued or sold under the Registration Statement. Accordingly, the withdrawal of the Registration Statement is consistent with the public interest and the protection of investors, as contemplated by Rule 477(a) under the Securities Act.

The Company acknowledges that no refund will be made for fees paid to the Commission in connection with the filing of the Registration Statement.

We would be grateful if you would please send copies of the written order granting withdrawal of the Registration Statement to Christopher Hill, Chief Executive Officer and Chief Financial Officer, Adaptimmune Therapeutics plc, at the above-referenced address, email address chris.hill@adaptimmune.com, with a copy to David S. Bakst at dbakst@mayerbrown.com.

Please do not hesitate to contact David Bakst at (212) 506 2551 if you have any questions regarding the foregoing.

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| |
|:---|
| Very truly yours, |
| /s/ Christopher Hill |
| Christopher Hill |
| Chief Executive Officer and Chief Financial Officer |
| Adaptimmune Therapeutics plc |

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cc: David S. Bakst, Mayer Brown LLP