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EXHIBIT 5.1
[Letterhead of Fulbright & Jaworski L.L.P.]
October 16, 2000
Securities and Exchange Commission
450 Fifth Street, NW
Washington, DC 20549
Ladies & Gentlemen:
We refer to the Registration Statement on Form S-3 (the
"Registration Statement"), filed by Alexion Pharmaceuticals, Inc. (the
"Company") with the Securities and Exchange Commission under the Securities Act
of 1933, as amended (the "Act"), relating to the proposed issuance and sale from
time to time pursuant to Rule 415 under the Act of up to $300,000,000 of common
stock, $.0001 par value ("Common Stock"), of the Company and/or warrants to
purchase Common Stock (the "Warrants") of the Company (the Common Stock and
Warrants are collectively referred to herein as the "Securities").
As counsel for the company, we have examined such corporate records,
documents and such questions of law as we have considered necessary or
appropriate for purposes of this opinion and, upon the basis of such
examination, advise you that, assuming that: (i) the Registration Statement and
any amendments thereto (including post-effective amendments) will have become
effective and comply with all applicable laws; (ii) the Registration Statement
will be effective and will comply with all applicable laws at the time the
Securities are offered or issued as contemplated by the Registration Statement;
(iii) a Prospectus Supplement, Pricing Supplement or term sheet will have been
prepared and filed with the Securities and Exchange Commission describing the
Securities offered thereby and will comply with all applicable laws; (iv) all
Securities will be issued and sold in compliance with applicable federal and
state securities laws and in the manner stated in the Registration Statement and
the appropriate Prospectus Supplement; (v) a definitive purchase, underwriting
or similar agreement with respect to any Securities offered or issued will have
been duly authorized and validly executed and delivered by the Company and the
other parties thereto; and (vi) any Securities issuable upon conversion,
exchange or exercise of any Security being offered or issued will be duly
authorized, created and, if appropriate, reserved for issuance upon such
conversion, exchange or exercise, in our opinion:
(1) with respect to shares of Common Stock, when both (A) the Board
of Directors has taken all necessary corporate action to approve the issuance of
and the terms of the offering of the shares of Common Stock and related matters
and (B) certificates representing the shares of Common Stock have been duly
executed, countersigned, registered and delivered either (i) in accordance with
the applicable definitive purchase, underwriting or similar agreement approved
by
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the Board upon payment of the consideration therefor (not less than the par
value of the Common Stock) provided for therein or (ii) upon conversion or
exercise of any other Security, in accordance with the terms of such Security or
the instrument governing such Security providing for such conversion or exercise
as approved by the Board, for the consideration approved by the Board (not less
than the par value of the Common Stock), then the shares of Common Stock will be
validly issued, fully paid and nonassessable; and
(2) with respect to the Warrants, when (A) the Board of Directors
has taken all necessary corporate action to approve the creation of and the
issuance and terms of the Warrants, the terms of the offering thereof, and
related matters, (B) the Warrant Agreement or Agreements relating to the
Warrants have been duly authorized and validly executed and delivered by the
Company and the Warrant Agent appointed by the Company, and (C) the Warrants or
certificates representing the Warrants have been duly executed, countersigned,
registered and delivered in accordance with the appropriate Warrant Agreement or
Agreements and the applicable definitive purchase, underwriting or similar
agreement approved by the Board upon payment of the consideration therefor
provided for therein, the Warrants will be validly issued.
We 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 and elsewhere in the Registration
Statement and Prospectus. 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.
Very truly yours,
/s/ Fulbright & Jaworski L.L.P.
