La Jolla Pharmaceutical Company
TABLE OF CONTENTS

SELLING STOCKHOLDERS


Table of Contents

Filed Pursuant to Rule 424(b)(3)
Registration Statement No. 333-81432

Prospectus Supplement No. 1
to
Prospectus Dated February 4, 2002

LA JOLLA PHARMACEUTICAL COMPANY

Common Stock


     The following information supplements, and must be read in connection with, the information contained in the Prospectus, dated February 4, 2002 (the “Prospectus”), of La Jolla Pharmaceutical Company, a Delaware corporation. This Prospectus Supplement must be delivered with a copy of the Prospectus. All capitalized terms not otherwise defined herein have the respective meanings ascribed to them in the Prospectus.

     The following information replaces in its entirety the information provided in the Prospectus under the caption “Selling Stockholders.”


SELLING STOCKHOLDERS

     In a series of private transactions completed on January 17, 2002, we issued a total of 7,000,000 shares of our common stock to the stockholders listed below. The selling stockholders may from time to time offer and sell pursuant to this prospectus any or all of 7,000,000 shares of our common stock. The following table describes, as of May 7, 2002, the number of shares of our common stock that each selling stockholder beneficially owns and the number of shares registered hereunder. The term “selling stockholders” includes the holders listed below and their transferees, pledgees, donees or other successors. We have prepared this table based upon information furnished to us by or on behalf of the selling stockholders.

     The selling stockholders confirmed at the time they acquired the shares listed below that they acquired the shares for investment purposes only and not with a view toward their resale, and acknowledged the existence of restrictions on resale that apply to these shares. This offering relates only to the sale of the 7,000,000 shares of common stock held or to be held by the selling stockholders named in the following table. Since the date on which they provided us with the information below, the selling stockholders may have sold, transferred or otherwise disposed of some or all of their shares of our common stock in transactions exempt from the registration requirements of the Securities Act.

                                         
    Shares of Common Stock   Shares of Common Stock
    Owned Prior to Offering   Owned After Offering
   
 
            Percent of   Shares to be   Number of   Percent of
Name of Selling Stockholder   Number of Shares   Class(%)(1)   Sold(2)   Shares(2)   Class(%)(2)

 
 
 
 
 
SAFECO Growth Opportunities Fund —
A series of SAFECO Common Stock Trust
    1,216,000       2.9       1,216,000              
Deka-Team-Biotech (3)
    1,019,009       2.4       484,450       534,559       1.3  
Deerfield Partners, L.P.
    746,936       1.8       139,750       607,186       1.4  
Deerfield International Limited
    589,264       1.4       110,250       479,014       1.1  
Growth Opportunities Fund —
A series of SAFECO Resource Series Trust
    584,000       1.4       584,000              
Brookside Capital Partners Fund, L.P.
    500,000       1.2       500,000              
SEI Institutional Managed Trust
    344,800       *       318,500       26,300       *  
Compound Capital Growth Partners, Ltd.
    320,294       *       320,294              

 


Table of Contents

                                         
    Shares of Common Stock   Shares of Common Stock
    Owned Prior to Offering   Owned After Offering
   
 
            Percent of   Shares to be   Number of   Percent of
Name of Selling Stockholder   Number of Shares   Class(%)(1)   Sold(2)   Shares(2)   Class(%)(2)

 
 
 
 
 
EGS Private Healthcare Partnership II, L.P.
    303,085       *       303,085              
Special Situations Fund III, L.P.
    285,000       *       285,000              
SEI Institutional Investments Trust
    257,200       *       237,200       20,000       *  
Zeke, LP
    225,000       *       225,000              
RS Smaller Company Growth Fund
    210,600       *       75,000       135,600       *  
SF Capital Partners, LTD
    200,000       *       200,000              
JP Morgan U.S. Small Company Fund
    170,750       *       28,350       142,400       *  
Compound Capital Growth Partners II, LP
    153,900       *       153,900              
Utah Retirement Systems
    141,000       *       130,100       10,900       *  
Special Situations Private Equity Fund, L.P.
    125,000       *       125,000              
Anvers Healthcare Investors, LP
    124,000       *       63,000       61,000       *  
Pierpont Small Company Opportunities Fund
    121,932       *       20,600       101,332       *  
CCGrowth Global Life Sciences Ltd.
    122,573       *       106,614       15,959       *  
UBS Global Equity Arbitrage Master Limited
    100,000       *       100,000              
O’Connor PIPES Corporate Strategies Ltd.
    100,000       *       100,000              
Special Situations Cayman Fund, L.P.
    90,000       *       90,000              
JPMCB U.S. Small Company Equity I Growth
    84,200       *       13,175       71,025       *  
G. Nicholas Farwell(4)
    75,000       *       75,000              
CCGrowth Global Life Sciences I, LP
    58,097       *       58,097             *  
RS Orphan Fund, L.P.
    70,000       *       70,000              
Compound Capital Growth Partners III, LP
    68,073       *       68,073              
Ivory Opportunity Fund, LP
    67,500       *       67,500              
JPM Tax Aware Small Company Opportunities Fund
    67,361       *       14,200       53,161       *  
Daughter’s of Charity Fund P
    61,900       *       57,100       4,800       *  
Undiscovered Managers Small Cap Growth Fund
    61,100       *       56,200       4,900       *  
Compound Capital Growth Partnership, LP
    50,799       *       50,799              
AIG DKR Soundshore Holdings Ltd.
    50,000       *       50,000              
EGS Private Healthcare Investors II, L.P.
    47,800       *       47,800              
EGS Private Healthcare Canadian Partners, L.P.
    45,607       *       45,607              
Vision Small Cap Stock Fund
    39,100       *       36,100       3,000       *  
Alfred I. Dupont Testamentary Trust
    33,300       *       30,700       2,600       *  
Ivory Opportunity Fund, Ltd.
    32,500       *       32,500              
Les Schwab P/S Retirement Trust
    30,300       *       28,000       2,300       *  
RS Orphan Offshore Fund, L.P.
    30,000       *       30,000              
CCGrowth Global Life Sciences II, LP
    35,741       *       30,954       4,787       *  
East Bay Municipal Utility District
    25,900       *       23,900       2,000       *  
Met. Inv. Tr Small Cap Stock — SSB
    25,425       *       3,925       21,500       *  
The Paisley Fund, LP
    25,000       *       25,000              
JP Morgan Global Healthcare Fund(3)
    22,709       *       3,850       18,859       *  
Anvers Healthcare Investors International, Ltd.
    22,700       *       12,000       10,700       *  
Philips Pensionenfondsen-Small Cap
    22,225       *       3,725       18,500       *  
Maximus Managed Offshore, Ltd.
    21,340       *       21,340              
Ret. Pl. For Union Carbide Corp.
    20,029       *       3,800       16,229       *  
Maximus Capital Investments, Ltd.
    18,870       *       18,870              
Westfiled Life Sciences Fund LP
    15,900       *       15,900              
JPMP Global Healthtech Fund(3)
    15,500       *       15,500              
JPMCB U.S. Small Company Equity II Growth
    15,475       *       2,650       12,825       *  
Memorial Hospital of South Bend, Inc.
    12,500       *       11,500       1,000       *  
PGH Pension
    11,600       *       10,700       900       *  
DSM NV PENS VERZ MIJ-Small Cap
    11,025       *       1,825       9,200       *  
JP Morgan Series Trust Small Company Growth Portfolio
    10,825       *       2,125       8,700       *  
Westfiled Life Sciences Fund LP II
    9,100       *       9,100              
Nemours Foundation
    8,000       *       7,400       600       *  

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Table of Contents

                                         
    Shares of Common Stock   Shares of Common Stock
    Owned Prior to Offering   Owned After Offering
   
 
            Percent of   Shares to be   Number of   Percent of
Name of Selling Stockholder   Number of Shares   Class(%)(1)   Sold(2)   Shares(2)   Class(%)(2)

 
 
 
 
 
Caddis Master Fund Ltd.
    6,934       *       6,934              
JP Morgan Diversified Fund
    6,900       *       1,825       5,075       *  
Maximus Managed Domestic, L.P.
    5,090       *       5,090              
The Baetis Fund, LP
    4,799       *       4,335       464       *  
Maximus Capital, L.P.
    4,700       *       4,700              
EGS Private Healthcare Presidents Fund, L.P.
    3,508       *       3,508              
Wilshire U.S. Equity Fund
    2,800       *       2,600       200       *  


*   Less than 1%
(1)   Computed based on 42,312,412 shares of common stock outstanding as of March 28, 2002.
(2)   Assumes all the shares of common stock that may be offered hereunder are sold.
(3)   Registered in the name of Cudd & Co.
(4)   50,000 shares of common stock are held in the name of G. Nicholas Farwell and Gail M. Farwell JTWROS, and 25,000 shares of common stock are held in the name of G. Nicholas Farwell — Sep. Pty.

The information regarding the selling stockholders may change from time to time. If required, we will describe these changes in one or more prospectus supplements.

The Date of This Prospectus Supplement Is May 7, 2002

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