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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                    FORM 8-K

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                                 CURRENT REPORT

                     PURSUANT TO SECTION 13 OR 15(d) OF THE

                         SECURITIES EXCHANGE ACT OF 1934

          Date of Report (Date of earliest event reported)       March 6.1998
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                          ALEXION PHARMACEUTICALS, INC.
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             (Exact Name of Registrant as Specified in its Charter)

        DELAWARE                        0-27756                   13-3648318
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     (State or Other                  (Commission                (IRS Employer
Jurisdiction of Incorporation)         File Number)          Identification No.)

     25 SCIENCE PAR, NEW HAVEN, CT                                  06511
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 (Address of Principal Executive Offices)                         (Zip Code)

Registrant's telephone number, including area code:  (203) 776-1790
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                                 NOT APPLICABLE
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          (Former Name or Former Address, if Changed Since Last Report)

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Item 5. Other Events

     On March 6, 1998, Alexion Pharmaceuticals, Inc. issued the press release
filed herewith as Exhibit 99.

Item 7.  Financial Statements, PRO FORMA Financial Information and Exhibits.

     (c)   Exhibits.

     99.   Press Release dated March 6, 1998.



                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                             ALEXION PHARMACEUTICALS, INC.

Date: March 6, 1998                          By: /s/  LEONARD BELL, M.D.
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                                             Name:   Leonard Bell, M.D.
                                             Title:  President, Chief Executive
                                                     Officer, Secretary and
                                                     Treasurer


                                                                      EXHIBIT 99
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Immediate Release  Contact:   Leonard Bell, M.D.       Rhonda Chiger (Investors)
                              President and CEO        Susan Farley (Media)
                              Alexion Pharmaceuticals  Dewe Rogerson, Inc.
                              203/776-1790             212/688-6840

            ALEXION ENTERS AGREEMENT WITH BB BIOTECH TO RECEIVE $8.8
                          MILLION IN PRIVATE PLACEMENT

New Haven, CT, March 6, 1998--Alexion Pharmaceuticals, Inc. (Nasdaq: ALXN) today
announced that it has entered into an agreement with a single institutional
investor, BB Biotech, to raise $8.827 million in a private placement of 670,000
shares of common stock.

"We are extremely pleased by the support BB Biotech continues to show us through
their multiple investments in the Company," said Dr. Leonard Bell, President and
Chief Executive Officer of Alexion. "In the Six months since BB Biotech's
initial investment, we have made significant progress in advancing our
technology into human clinical trials. We currently have four clinical
development programs underway, with our first product candidate having
substantially completed a Phase IIa cardiopulmonary bypass study, and additional
product candidates targeting rheumatoid arthritis, systemic lupus, and multiple
sclerosis patients. We believe that the proceeds from this placement will allow
us to further augment and more broadly advance the manufacturing, clinical
development and preclinical development of our C5 complement inhibitors and
Apogens candidates."

Proceeds from the private placement will be used to fund the Company's research
and development activities including ongoing and planned clinical studies,
production of clinical trial material, preclinical studies, and for general
corporate purposes. The financing will close upon the effectiveness of the
resale registration statement to be filed by the Company with the Securities and
Exchange Commission in connection with these shares. Following the close of this
transaction, Alexion's cash position will be approximately $45 million.

Alexion Pharmaceuticals, Inc. was founded in 1992 and in engaged in the
development of selective immunotherapeutic drugs that generally are designed to
inhibit the disease-causing segments of the immune system while preserving the
disease-preventing aspects of the immune system. The Company is developing three
technology platforms: C5 Complement Inhibitors and Apogen T-Cell Therapeutics
which together target severe cardiovascular and autoimmune disorders; and
xenografts for organ transplants.

This news release contains forward looking statements. Such statements are
subject to certain factors which may cause Alexion's plans to differ or results
to vary from those expected including unexpected preclinical or clinical
results, the need for additional research and testing, delays in manufacturing,
access to capital and funding, delays in



development of commercial relationships and a variety of risks set forth from
time to time in Alexion's filings with the Securities and Exchange Commission,
including but not limited to the risks discussed in Alexion's Annual Report on
Form 10-K for the year ended July 31, 1997. Alexion undertakes no obligation to
publicly release the results of any of these forward looking statements which
may be made to reflect events or circumstances after the date hereof or to
reflect the occurrence of unanticipated events. The shares of Common Stock have
not been registered under the Securities Act of 1933, as amended, and may not be
offered and sold in the United States absent registration under such Act or an
applicable exemption from registration. This press release shall not constitute
an offer to sell or the solicitation of an offer to buy the Common Stock nor
shall there be any sale of these securities in any state in which such offer,
solicitation or sale would be unlawful prior to registration or qualification
under the securities laws of any such state.