FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
ORBIMED ADVISORS LLC
  2. Issuer Name and Ticker or Trading Symbol
Adaptimmune Therapeutics PLC [ADAP]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
601 LEXINGTON AVENUE, 54TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
05/20/2016
(Street)

NEW YORK, NY 10022-4629
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
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
Ordinary Shares with a nominal value of GBP0.001 per share (1) 05/20/2016   P   2,400 A $ 10.04 (2) 28,043,404 I See Footnotes (5) (6)
Ordinary Shares with a nominal value of GBP0.001 per share (1) 05/23/2016   P   1,191,600 A $ 10.4 (3) 29,235,004 I See Footnotes (5) (6)
Ordinary Shares with a nominal value of GBP0.001 per share (1) 05/24/2016   P   518,400 A $ 10.48 (4) 29,753,404 I See Footnotes (5) (6)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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 Underlying Securities
(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 of Derivative Security: 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

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
ORBIMED ADVISORS LLC
601 LEXINGTON AVENUE, 54TH FLOOR
NEW YORK, NY 10022-4629
  X      
OrbiMed Capital GP V LLC
601 LEXINGTON AVENUE, 54TH FLOOR
NEW YORK, NY 10022
  X      
ISALY SAMUEL D
601 LEXINGTON AVENUE, 54TH FLOOR
NEW YORK, NY 10022
  X      

Signatures

 /s/ Samuel D. Isaly   05/25/2016
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) The ordinary shares whose purchase is reported on this line are represented by American Depositary Shares ("ADSs") held of record by OrbiMed Private Investments V, LP ("OPI V"). OPI V holds these ordinary shares in the form of ADSs. Each ADS represents six ordinary shares of Adaptimmune Therapeutics plc. Of the amount of securities reported in column 5, OPI V holds 25,408,300 shares directly in the form of ordinary shares, and the balance of the ordinary shares are represented by ADSs.
(2) The price reported in Column 4 is a weighted average price. These shares of the Issuer's common stock ("Shares") were purchased in multiple transactions at prices ranging from $10.03 to $10.05 inclusive. Upon request, the Reporting Persons undertake to provide the Issuer, any security holder of the Issuer, or the Securities and Exchange Commission (the "SEC") full information regarding the Shares purchased at each separate price within the range set forth in this footnote.
(3) The price reported in Column 4 is a weighted average price. These Shares were purchased in multiple transactions at prices ranging from $10.15 to $10.55 inclusive. Upon request, the Reporting Persons undertake to provide the Issuer, any security holder of the Issuer, or the SEC full information regarding the Shares purchased at each separate price within the range set forth in this footnote.
(4) The price reported in Column 4 is a weighted average price. These Shares were purchased in multiple transactions at prices ranging from $10.45 to $10.52 inclusive. Upon request, the Reporting Persons undertake to provide the Issuer, any security holder of the Issuer, or the SEC full information regarding the Shares purchased at each separate price within the range set forth in this footnote.
(5) These securities are held of record by OPI V. OrbiMed Capital GP V LLC ("GP V") is the sole general partner of OPI V, and OrbiMed Advisors LLC ("Advisors"), a registered adviser under the Investment Advisors Act of 1940, as amended, is the sole managing member of GP V. Samuel D. Isaly ("Isaly"), a natural person, is the managing member of, and holder of a controlling interest in, Advisors. By virtue of such relationships, GP V, Advisors and Isaly may be deemed to have voting and investment power with respect to the securities held by OPI V noted above and as a result may be deemed to beneficially own such securities for purposes of Rule 13d-3 under the Securities Exchange Act of 1934, as amended (the "Exchange Act").
(6) This report on Form 4 is jointly filed by GP V, Advisors, and Isaly. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Exchange Act, except to the extent of its or his pecuniary interest therein, if any. The Reporting Persons have designated a representative, currently Peter A. Thompson, an employee of Advisors, to serve on the Issuer's board of directors. This report shall not be deemed an admission that any of the Reporting Persons is a beneficial owner of such securities for the purpose of Section 16 of the Exchange Act, or for any other purpose.

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