Filed Pursuant to
Rule 424(b)(3) and (c)
File No. 333-115516

Prospectus Supplement
Dated December 21, 2004

InterMune, Inc.
$170,000,000 .25% Convertible Senior Notes Due 2011

        This prospectus supplement supplements the prospectus, dated October 27, 2004, of InterMune, Inc. ("InterMune") relating to the resale by selling securityholders of InterMune's .25% Convertible Senior Notes Due March 1, 2011. This prospectus supplement should be read in conjunction with the prospectus, and is qualified by reference to the prospectus, except to the extent that the information presented herein supersedes the information contained in the prospectus. This prospectus supplement is not complete without, and may not be delivered or utilized except in connection with, the prospectus, including any amendments or supplements thereto.

        Investing in our securities involves a high degree of risk. See "Risk Factors" beginning on page 5 of the prospectus.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        The table appearing on pages 62 through 64 of the prospectus under the caption "Selling Securityholders" is amended and restated to include the following securityholders:

SELLING SECURITYHOLDERS

        We originally issued and sold the notes to the initial purchasers in transactions exempt from the registration requirements of the Securities Act, and the initial purchasers immediately resold the notes to persons they reasonably believed to be qualified institutional buyers. Selling holders, including their transferees, pledgees or donees or their successors, may from time to time offer and sell pursuant to this prospectus any or all of the notes and common stock into which the notes are convertible.

        The following table sets forth information with respect to the selling holders and the principal amounts of notes beneficially owned by each selling holder that may be offered under this prospectus. The information is based on information provided by or on behalf of the selling holders. The selling holders may offer all, some or none of the notes or common stock into which the notes are convertible. Because the selling holders may offer all or some portion of the notes or the common stock, no estimate can be given as to the amount of the notes or the common stock that will be held by the selling holders upon termination of any sales: the table below assumes that all selling holders will sell all of their notes or common stock, unless otherwise indicated. In addition, the selling holders identified below may have sold, transferred or otherwise disposed of all or a portion of their notes or common stock since the date on which they provided the information regarding their notes and common stock in transactions exempt from the registration requirements of the Securities Act. No offer or sale under this prospectus may be made by a security holder unless that security holder is listed in the table below.

2

3

*

Less than one percent.

(1)

Information about other selling holders will be set forth in post-effective amendments, if required.

(2)

The total principal amount of notes and shares of common stock issuable upon conversion of notes listed in the table may be more than $170,000,000 and 7,858,811 shares, respectively, because certain of the selling securityholders may have sold, transferred or otherwise disposed of all or a portion of their notes in transactions exempt from the registration requirements of the Securities Act since the date on which they provided information regarding their notes for inclusion in this table. The maximum principal amount of notes and number of shares of common stock issuable upon conversion of the notes that may be sold under this prospectus will not exceed $170,000,000 and 7,858,811 shares, respectively.

(3)

Unless otherwise noted, represents shares of common stock issuable upon conversion of the notes.

(4)

Includes shares of common stock held.

(5)

The selling securityholder is an affiliate of a broker dealer who purchased the securities in the ordinary course of business and at the time of the purchase of the securities to be resold, the selling securityholder had no agreement or understandings, directly or indirectly, with any person to distribute the securities.

(6)

Because Deutsche Banc Securities Inc. ("Deutsche Banc") is a broker-dealer, it is deemed to be an "underwriter" within the meaning of Section 2(11) of the Securities Act. As a result, any profits on the sale of the securities by Deutsche Banc, and any discounts, commissions or concessions received by Deutsche Banc, will be deemed to be underwriting discounts and commissions under the Securities Act.

(7)

Includes 197,750 shares of common stock and 750 October 15, 2004 call options held.

(8)

Includes 39,550 shares of common stock and 750 October 15, 2004 call options held.

(9)

Includes 92,457 shares of common stock issuable upon conversion of $2,000,000 in principal amount of .25% Convertible Senior Notes Due 2011 that are not offered by this prospectus.

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