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EXHIBIT 12.1
STATEMENT REGARDING COMPUTATION OF RATIOS
Aviron
Ratio of fixed charges
(in thousands, except ratio)
<TABLE>
<CAPTION>
NINE MONTHS
YEARS ENDED DECEMBER 31, ENDED
---------------------------------------------------- SEPTEMBER 31,
1995 1996 1997 1998 1999 2000
------- ------- ------- ------- ------- -------
<S> <C> <C> <C> <C> <C> <C>
Net Loss ............................................. (11,403) (17,501) (26,502) (54,802) (61,870) (57,007)
Add: Fixed charges ................................... 190 245 239 5,022 6,620 6,421
------- ------- ------- ------- ------- -------
Earnings as defined .................................. (11,213) (17,256) (26,263) (49,780) (55,250) (50,586)
======= ======= ======= ======= ======= =======
Estimated interest component of rent ................. 32 53 60 140 256 244
Interest expense (1) ................................. 158 192 180 4,882 6,364 6,177
------- ------- ------- ------- ------- -------
Total fixed charges .................................. 190 245 239 5,022 6,620 6,421
======= ======= ======= ======= ======= =======
Ratio ................................................ (2) (2) (2) (2) (2) (2)
</TABLE>
(1) Includes amortization of debt issuance costs
(2) Earnings (as defined) for the period were insufficient to cover
fixed charges by an amount equal to the net loss for the period.
