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                                                                      Exhibit 12

                        CENTOCOR, INC. AND SUBSIDIARIES
                      STATEMENT RE COMPUTATION OF RATIOS
                      RATIO OF EARNINGS TO FIXED CHARGES
                                (in thousands)

<TABLE> 
<CAPTION> 
                                      1996        1995        1994        1993         1992      
                                   ----------  ----------  ----------  -----------  ----------   
<S>                                <C>         <C>         <C>         <C>          <C>          
EARNINGS (LOSS):                                                                                
                                                                                                
Loss                                ($12,763)    ($57,132)  ($126,658)    ($74,379)  ($194,146)  
                                                                                                
PLUS:                                                                                           
                                                                                                
Fixed charges (below)                  9,648       18,903      21,719       22,820      24,046   
                                                                                                
LESS:                                                                                           
                                                                                                
Interest capitalized                       -            -           -            -           -   
                                   ----------  ----------  ----------  -----------  ----------   
ADJUSTED EARNINGS (LOSS)             ($3,115)    ($38,229)  ($104,939)    ($51,559)  ($170,100) 


FIXED CHARGES:   

Rent expense deemed interest          $1,138       $1,191      $1,187       $1,987      $3,537

Interest expense                       8,351       17,001      19,821       20,087      19,798        
                                                                                                
Amortization of debt issuance cost       159          711         711          746         711           
                                                                                                
Interest  capitalized                      -            -           -            -           -            
                                   ----------  ----------  ----------  -----------  ----------   
TOTAL FIXED CHARGES                   $9,648      $18,903     $21,719      $22,820     $24,046       
                                                                                                 
RATIO                                   *           *           *            *           *      
                                        -           -           -            -           -             
</TABLE> 


* Adjusted earnings did not cover fixed charges for the years ended December 31,
1996, 1995, 1994, 1993, and 1992 by $12,763,000, $57,132,000, $126,658,000,
$74,379,000, and $194,146,000 respectively.