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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): July 7, 1998


                          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 PARK, 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


                                 NOT APPLICABLE
           -----------------------------------------------------------
          (Former Name or Former Address, if Changed Since Last Report)

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ITEM 5. OTHER EVENTS

     On July 7, 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 July 7, 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: July 7, 1998                         By: /s/  LEONARD BELL, M.D.
                                               -------------------------
                                               Name:  Leonard Bell, M.D.
                                               Title: President, Chief Executive
                                                      Officer, Secretary and
                                                      Treasurer


                                                                      EXHIBIT 99


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 BEGINS C5 INHIBITOR CLINICAL TRIAL
                            FOR RHEUMATOID ARTHRITIS

         --Alexion Moves into Clinic Treating Autoimmune Disorder with
                   Second Anti-Inflammatory Drug Candidate--


NEW HAVEN, CT, July 7, 1998--Alexion Pharmaceuticals, Inc. (Nasdaq: ALXN) today
announced that it has recently commenced dosing Rheumatoid Arthritis (RA)
patients in a Phase I/II clinical trial of its anti-inflammatory complement
inhibitor drug candidate 5G1.1. The multi-center, double-blinded,
placebo-controlled, ascending dose study is expected to enroll 40 patients. The
trial is designed to gather clinical data regarding the safety profile and
biological effects of 5G1.1 in this patient population.

"We are pleased to be advancing our product pipeline by initiating clinical
trials for our second drug candidate, 5G1.1," said Leonard Bell, M.D., President
and Chief Executive Officer of Alexion. "In pursuing this new clinical target,
which builds on the anti-inflammatory properties of our proprietary complement
inhibitor approach that has been already observed in the clinic, we are taking
an important step closer to providing needed treatment for rheumatoid
arthritis."

The anti-inflammatory effects of Alexion's first drug candidate, 5G1.1-SC, were
recently reported to significantly reduce cardiac damage, new cognitive (brain)
deficits, and blood loss in patients undergoing coronary artery bypass graft
surgery. Alexion has previously announced plans to begin clinical development of
5G1.1-SC for the treatment of acute myocardial infarction (heart attack) later
this year.

Louis Matis, M.D., Senior Vice President and Chief Scientific Officer, said,
"The initiation of this clinical study in RA patients is a satisfying step
towards the realization of the potential of our pre-clinical findings of C5
Inhibitors showing potent and selective anti-inflammatory effects in an animal
model of RA. In the arthritis studies that were published in the Proceedings of
the National Academy of Sciences, we saw a dramatic reduction in inflammation of
affected joints in individuals with established disease and a greater than 90%
reduction in disease incidence. We believe that the significant reductions in
levels of biological markers associated with inflammation seen in our clinical
trial studies of 5G1.1-SC give us a good indication that the related 5G1.1 drug
candidate will also show beneficial anti-inflammatory effects."






Approximately 2,500,000 patients currently receive therapy for rheumatoid
arthritis in the U.S. In such patients, the attack of the individual's immune
system against multiple joints throughout the body frequently leads to severe
joint destruction, pain, and disfigurement.

Alexion's C5 inhibitors (5G1.1 and 5G1.1-SC) are specific and potent recombinant
drugs which are designed to intervene in the complement cascade. The Company
believes that these proprietary G5 Inhibitors intervene at an optimal point
which generally preserves the normal disease-preventing functions of complement
proteins while generally inhibiting the disease-causing actions. 5G1.1 is a
novel fully humanized monoclonal antibody, specifically designed to deliver
potent anti-complement and anti-inflammatory activity to patients suffering from
chronic inflammatory diseases, including the autoimmune disorders rheumatoid
arthritis and systematic lupus. In its other autoimmne disease programs, Alexion
expects to initiate clinical trials with 5G1.1 in systemic lupus patients this
summer. Further, with regard to its MS program, Alexion has indicated to the FDA
that the initiation of clinical trials is delayed as it is conducting additional
preclinical studies with MP4 so as to evaluate the safest and most effective
dosing route and regimen prior to the amendment of the clinical protocol for the
subsequent treatment of MS patients.

Alexion Pharmaceuticals, Inc. was funded in 1992 and is 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 transplantation.

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 PRE-CLINICAL 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 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.