ALXN Alexion Pharmaceuticals Inc

FORM 4 [X] 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                                                                                   
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940                       

1. Name and Address of Reporting Person * Brennan David R	2. Issuer Name and Ticker or Trading Symbol ALEXION PHARMACEUTICALS, INC. [ ALXN ]	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) C/O ALEXION PHARMACEUTICALS, INC, 121 SEAPORT BOULEVARD	3. Date of Earliest Transaction (MM/DD/YYYY) 7/21/2021
(Street) BOSTON, MA 02210 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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, par value $.0001 per share	7/21/2021		D		20873 (1)	D	$0	0	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		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 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
Option to Purchase Common Stock	$155.01	7/21/2021		D			2343	5/6/2016 (2)	5/6/2025	Common Stock, par value $.0001 per share	2343.0	$155.01	0	D
Option to Purchase Common Stock	$167.97	7/21/2021		D			2706	7/22/2015 (2)	7/22/2024	Common Stock, par value $.0001 per share	2706.0	$167.97	0	D
Option to Purchase Common Stock	$138.86	7/21/2021		D			2294	5/11/2017 (2)	5/11/2026	Common Stock, par value $.0001 per share	2294.0	$138.86	0	D

Explanation of Responses:
(1)	Represents shares of Alexion common stock disposed in connection with the Agreement and Plan of Merger (the "Merger Agreement") dated as of December 12, 2020, by and among Alexion and AstraZeneca PLC. In accordance with the Merger Agreement, upon the First Effective Time (as defined in the Merger Agreement), each share of Alexion common stock was converted into the right to receive (i) 2.1423 American Depositary Shares (ADSs) of AstraZeneca PLC and (ii) $60.00 in cash (the "Merger Consideration"). Upon the First Effective Time, 3,336 restricted stock units were fully vested and cancelled and converted into the right to receive the Merger Consideration with respect to each share of Alexion common stock subject to such restricted stock units.
(2)	Upon the First Effective Time, these options were cancelled and converted into the right to receive the product obtained by multiplying (A) the excess, if any, of the value of the Merger Consideration over the exercise price per share of the Alexion common stock subject to such options immediately prior to the First Effective Time by (B) the number of shares of Alexion common stock subject to such option immediately prior to the First Effective Time by (ii) the value of the Merger Consideration.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Brennan David R C/O ALEXION PHARMACEUTICALS, INC 121 SEAPORT BOULEVARD BOSTON, MA 02210	X

Signatures
/s/ Douglas Barry, Attorney-in-Fact for David R. Brennan.		7/23/2021
**Signature of Reporting Person		Date