<PAGE>
Registration No. 333-91265
As filed with the Securities and Exchange Commission on November 23, 1999
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
------------------------
POST-EFFECTIVE
AMENDMENT
NO. 1
TO
FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
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ALEXION PHARMACEUTICALS, INC.
(Exact name of Registrant as specified in its charter)
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DELAWARE 13-3648318
(State or other jurisdiction of (I.R.S. Employer
incorporation or organization) Identification No.)
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25 SCIENCE PARK
NEW HAVEN, CT 06511
(203) 498-4210
(Address, including zip code, and telephone number, including area code, of
Registrant's principal executive offices)
------------------------------
LEONARD BELL, M.D.
ALEXION PHARMACEUTICALS, INC.
25 SCIENCE PARK
NEW HAVEN, CT 06511
(203) 776-1790
(Name, address, including zip code, and telephone number, including area code,
of agent for service)
------------------------------
with copies to:
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MERRILL M. KRAINES, ESQ. DAVID R. KING, ESQ.
LAWRENCE A. SPECTOR, ESQ. MICHAEL J. SHIM, ESQ.
FULBRIGHT & JAWORSKI L.L.P. MORGAN, LEWIS & BOCKIUS LLP
666 FIFTH AVENUE 1701 MARKET STREET
NEW YORK, NEW YORK 10103 PHILADELPHIA, PENNSYLVANIA 19103
(212) 318-3000 (215) 963-5000
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APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: As soon as
practicable after the effective date of this Registration Statement.
If any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, check the following box: [ ]
If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. [X] 333-89343
If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration number of the earlier effective registration statement for the same
offering. [ ]
If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box. [X]
THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THE REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(A) OF
THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL THEREAFTER
BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID
SECTION 8(A), MAY DETERMINE.
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ITEM 16. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.
(a) Exhibits.
5.1 Opinion of Fulbright & Jaworski L.L.P.
23.1 Consent of Arthur Andersen LLP.*
23.2 Consent of Fulbright & Jaworski L.L.P. (contained in Exhibit
5.1).
24.1 Power of Attorney.*
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* Previously filed.
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SIGNATURES
PURSUANT TO THE REQUIREMENTS OF THE SECURITIES ACT OF 1933, AS AMENDED, THE
REGISTRANT HAS DULY CAUSED THIS POST-EFFECTIVE AMENDMENT NO. 1 TO THIS
REGISTRATION STATEMENT TO BE SIGNED ON ITS BEHALF BY THE UNDERSIGNED, THEREUNTO
DULY AUTHORIZED, IN THE CITY OF NEW HAVEN AND STATE OF CONNECTICUT ON THE 23RD
DAY OF NOVEMBER, 1999.
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ALEXION PHARMACEUTICALS, INC.
By: /s/ LEONARD BELL
-----------------------------------------
Leonard Bell, M.D.
PRESIDENT, CHIEF EXECUTIVE OFFICER,
SECRETARY AND TREASURER
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Pursuant to the requirements of the Securities Act of 1933, as amended, this
Post-Effective Amendment No. 1 to this Registration Statement has been signed by
the following persons in the capacities and on the dates indicated:
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President, Chief Executive
/s/ LEONARD BELL Officer, Secretary,
------------------------------------------- Treasurer and Director November 23, 1999
Leonard Bell, M.D. (principal executive
officer)
Executive Vice President
/s/ DAVID W. KEISER and Chief Operating
------------------------------------------- Officer (principal November 23, 1999
David W. Keiser financial officer)
Vice President of Finance
* and Administration
------------------------------------------- (principal accounting November 23, 1999
Barry P. Luke officer)
*
------------------------------------------- Chairman of the Board of November 23, 1999
John H. Fried, Ph.D. Directors
------------------------------------------- Director
Jerry T. Jackson
*
------------------------------------------- Director November 23, 1999
Joseph A. Madri, Ph.D., M.D.
*
------------------------------------------- Director November 23, 1999
Leonard Marks, Jr., Ph.D.
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*
------------------------------------------- Director November 23, 1999
Max Link, Ph.D.
*
------------------------------------------- Director November 23, 1999
Eileen M. More
------------------------------------------- Director
R. Douglas Norby
------------------------------------------- Director
Alvin S. Parven
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*By: /s/ LEONARD BELL
--------------------------------------
Leonard Bell, M.D.
AS ATTORNEY-IN-FACT
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Exhibit 5.1
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HOUSTON
FULBRIGHT & JAWORSKI L.L.P. WASHINGTON, D.C.
TELEPHONE: 212/318-3000 A REGISTERED LIMITED LIABILITY AUSTIN
FACSIMILE: 212/752-5958 PARTNERSHIP SAN ANTONIO
666 FIFTH AVENUE DALLAS
NEW YORK, NEW YORK 10103 NEW YORK
LOS ANGELES
LONDON
HONG KONG
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November 23, 1999
Alexion Pharmaceuticals, Inc.
25 Science Park
New Haven, Connecticut 06511
Ladies and Gentlemen:
We have acted as counsel to Alexion Pharmaceuticals, Inc., a Delaware
corporation (the "Company"), in connection with its filing with the Securities
and Exchange Commission of a Registration Statement on Form S-3 (as amended, the
"Abbreviated Registration Statement"), under the Securities Act of 1933, as
amended (the "Act") for the registration of 500,000 shares of common stock, par
value $.0001 per share, of the Company (the "Common Stock") and up to an
additional 40,000 shares of Common Stock subject to an option (the
"Over-Allotment Option") from the Company to the underwriters, exercisable
within thirty (30) days after the effective date of the Registration Statement,
to cover over-allotments. The Abbreviated Registration Statement relates to the
same class of securities registered pursuant to the Company's Registration
Statement on Form S-3 (No. 333-89343) declared effective on November 19, 1999
(the "Initial Registration Statement").
The Abbreviated Registration Statement, together with the Initial
Registration Statement (collectively, the "Registration Statement"), relate to
the proposed sale by the Company in a public offering of an aggregate of
3,000,000 shares of the Company's Common Stock. The Registration Statement also
relates to the proposed sale by the Company of an aggregate of up to an
additional 415,000 shares of Common Stock subject to the Over-Allotment Option.
All such shares of Common Stock are hereinafter referred to as the "Shares."
In connection with this opinion, we, as counsel for the Company, have
examined such corporate records, other documents and questions of law as we have
considered necessary or appropriate for the purposes of this opinion. Our
opinion set forth below is limited to the General Corporation Law of the State
of Delaware.
We assume that appropriate action will be taken, prior to the offer and
sale of the Shares, to register and qualify the Shares for sale under all
applicable state securities or "blue sky" laws.
In our examination of the foregoing documents, we have assumed the
genuineness of all signatures and the authenticity of all documents submitted to
us as originals, the conformity to original documents of all documents submitted
to us as certified or photostatic copies, and the authenticity of the originals
of such latter documents.
Based on and subject to the foregoing, we advise you that in our
opinion, the Shares to be sold by the Company have been duly and validly
authorized and, when issued and sold in the manner contemplated by the
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November 23, 1999
Page 2
Purchase Agreement, a form of which has been filed as an exhibit to the
Registration Statement (the "Purchase Agreement"), and upon receipt by the
Company of payment therefor as provided in the Purchase Agreement, will be duly
and validly authorized, legally issued, fully paid and non-assessable.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and the reference to this firm under the caption "Legal
Matters" in the prospectus contained therein. This consent is not to be
construed as an admission that we are a party whose consent is required to be
filed with the Registration Statement under the provisions of the Act or the
rules and regulations of the Securities and Exchange Commission promulgated
thereunder. The opinion expressed herein is solely for your benefit, and may be
relied upon only by you.
Very truly yours,
/s/ Fulbright & Jaworski L.L.P.
