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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                          -----------------------------
                                    FORM 8-K
                          -----------------------------

                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported) January 26, 1999


                          ALEXION PHARMACEUTICALS, INC.
             (Exact name of registrant as specified in its charter)

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


      25 SCIENCE PARK, NEW HAVEN, CT                                   06511
(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 January 26, 1999, 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 January 26, 1999.


                                       -2-


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                                   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.


Dated: January 28, 1999     By: /S/ LEONARD BELL
                                ------------------------------------------------

                            Name:  Leonard Bell, M.D.
                            Title: President, Chief Executive Officer, Secretary
                                                     and Treasurer



                                       -3-









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                                                                      EXHIBIT 99

<TABLE>
<CAPTION>

             FOR IMMEDIATE RELEASE
             <S>                              <C>
             Alexion Contacts:
             Leonard Bell, M.D.               Lisa Burns, Justin Jackson (Media)
             President and CEO                Burns McClellan 212-213-0006
             Alexion Pharmaceuticals          Rhonda Chiger (Investor Relations)
             203/776-1790                     Thomson Investor Relations
                                              212-440-9037

             P&G Contacts:
             Jim Martis (Investor Relations) 513-983-9974
             Terry Loftus (Public Affairs) 513-945-8055
</TABLE>


         ALEXION PHARMACEUTICALS AND PROCTOR & GAMBLE PHARMACEUTICALS ENTER DRUG
         DEVELOPMENT COLLABORATION FOR ACUTE CARDIOVASCULAR INDICATIONS

NEW HAVEN, CT, JANUARY 26, 1999 -- Alexion Pharmaceuticals, Inc. (Nasdaq: ALXN)
and Procter & Gamble Pharmaceuticals (NYSE: PG) today announced that the two
companies have entered into a collaboration to develop and commercialize
Alexion's lead C5 complement inhibitor drug candidate, 5G1.1-SC, currently in
Phase IIb clinical trials for patients undergoing cardiopulmonary bypass (CPB)
during coronary artery bypass graft (CABG) surgery. Under the terms of the
collaboration agreement, development efforts will concurrently assess 5G1.1-SC
in the settings of CABG, angioplasty and other acute cardiovascular indications,
such as myocardial infarction and unstable angina, as well as other
applications. Procter & Gamble will receive development and marketing rights. In
return, Alexion will receive up to $95 million in total payments, which may
include up to $39 million in pre-commercialization milestone payments. In
addition, Alexion retains the right for commercial manufacturing as well as
co-promotion rights in the U.S.

Leonard Bell, M.D., President and Chief Executive Officer of Alexion, stated,
"We believe that Alexion's collaboration with P&G is the most comprehensive
effort to date in the area of complement inhibition for acute cardiovascular
disease." Dr. Bell continued, "Within the next 12 months, the collaborative team
expects to undertake advanced clinical developments in over one thousand
cardiopulmonary bypass patients and heart attack patients. This will provide
Alexion with the opportunity to substantially accelerate the rate of clinical
development with the objective of commercializing our product at the earliest
possible timepoint. Further, coming on the heels of P&G's successful NDA
submission for Azimilide, a pioneering anti-arrhythmic cardiovascular drug, we
believe that this collaboration is ideally timed to benefit from an established
network of clinical development professionals who are experienced in
cardiovascular trials."



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"As evidenced by this collaboration, P&G Pharmaceuticals is committed to further
developing its cardiac pipeline," said Mark A. Collar, head of Procter & Gamble
Pharmaceuticals. "In addition to a substantial in house cardiac R&D program, we
are working to supplement this effort with a few highly promising external
relationships with innovative biotech companies like Alexion Pharmaceuticals
which have promising technologies with breakthrough potential. Further, this new
opportunity in the cardiac area works well with our effort on Azimilide - an
investigational anti-arrhythmic drug currently being reviewed by the FDA."

Results from Phase I/II and Phase IIa CPB studies completed by Alexion last year
showed that 5G1.1-SC significantly reduces cardiac damage, new cognitive (brain)
deficits, and blood loss in patients undergoing CABG surgery during CPB. Alexion
also recently completed dosing of 5G1.1- SC in a Phase I study which was
designed to support the CABG studies as well as an anticipated heart attack
trial. Alexion's preclinical surrogates for 5G1.1-SC were demonstrated to
substantially reduce the myocardial infarction resulting from coronary ischemia
in a variety of different experimental models of heart attack and angioplasty
published in the June 9, 1998 issue of the American Heart Association's journal
Circulation.

According to the most recent statistics available from the American Heart
Association, approximately 1,000,000 patients suffer a heart attack, about
400,000 patients undergo angioplasty procedures, and approximately 500,000 CPB
procedures are performed in the U.S. each year. Further, according to the same
AHA statistics, in excess of $20 billion is spent annually on CABG surgery and
CABG-related medical care in the U.S. alone.

Alexion's class of C5 complement inhibitors are specific and potent recombinant
drugs which are designed to intervene in the complement cascade by preserving
the normal disease-preventing functions of complement proteins while generally
inhibiting the disease-causing actions. The Company's lead C5 Inhibitor product,
5G1.1-SC, is a novel, bacterially produced, humanized single chain antibody,
specifically designed to rapidly penetrate tissue and limit inflammation.

Procter & Gamble Pharmaceuticals is a part of Procter & Gamble Company, a $38
billion leader in the development, manufacturing and marketing of consumer
goods. In prescription medicines, P&GP is focusing on cardiovascular and
musculoskeletal health as well as anti-infective therapies. In the
cardiovascular area, P&G submitted a new drug application for Azimilide with the
U.S. Food and Drug Administration in December 1998. Azimilide is an
investigational anti-arrhythmic drug. P&GP is seeking an indication for the
maintenance of sinus heart rhythm by prolonging the arrhythmia-free period in
patients with atrial fibrillation, atrial flutter or paroxysmal supraventricular
tachycardias (PSVT) - - various form of irregular heartbeat.

Alexion Pharmaceuticals, Inc. was founded 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 


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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 AND ADVERSE CHANGES 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, 1998. 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.