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OFFER TO PURCHASE FOR CASH
ALL OUTSTANDING SHARES OF COMMON STOCK
(INCLUDING THE ASSOCIATED RIGHTS TO PURCHASE SERIES A JUNIOR PREFERRED STOCK)
OF
PATHOGENESIS CORPORATION
AT
$38.50 NET PER SHARE
BY
PICARD ACQUISITION CORP.
A WHOLLY OWNED SUBSIDIARY OF
CHIRON CORPORATION
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THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON MONDAY, SEPTEMBER 18, 2000, UNLESS THE OFFER IS EXTENDED.
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August 21, 2000
To Brokers, Dealers, Commercial Banks,
Trust Companies And Other Nominees:
We have been appointed by Picard Acquisition Corp., a Delaware corporation
("Merger Sub") and a wholly owned subsidiary of Chiron Corporation, a Delaware
corporation ("Parent"), to act as Dealer Manager in connection with Purchaser's
offer to purchase all outstanding shares of common stock, par value $0.001 per
share (the "Common Stock"), of PathoGenesis Corporation, a Delaware corporation
(the "Company"), together with the associated rights to purchase Series A Junior
Preferred Stock (the "Rights") issued pursuant to the Rights Agreement, dated as
of June 26, 1997, as amended (the "Rights Agreement"), between the Company and
Harris Trust and Savings Bank (the Common Stock and the Rights together being
referred to herein as the "Shares"), at a purchase price of $38.50 per Share,
net to the seller in cash, without interest (the "Offer Price"), upon the terms
and subject to the conditions set forth in the Offer to Purchase dated
August 21, 2000, and in the related Letter of Transmittal (which, together with
any amendments or supplements hereto or thereto, collectively constitute the
"Offer"). Please furnish copies of the enclosed materials to those of your
clients for whose accounts you hold Shares registered in your name or in the
name of your nominee.
THE OFFER IS CONDITIONED UPON, AMONG OTHER THINGS, (I) THERE BEING VALIDLY
TENDERED AND NOT WITHDRAWN PRIOR TO THE EXPIRATION OF THE OFFER THAT NUMBER OF
SHARES WHICH, WHEN ADDED TOGETHER WITH ALL OTHER SHARES OWNED BY CHIRON
CORPORATION AND ITS SUBSIDIARIES, WOULD REPRESENT AT LEAST A MAJORITY OF THE
OUTSTANDING SHARES (DETERMINED ON A FULLY DILUTED BASIS FOR ALL OUTSTANDING
STOCK OPTIONS AND OTHER RIGHTS (OTHER THAN THE RIGHTS,
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IF SUCH RIGHTS ARE NOT AT THAT TIME EXERCISABLE) TO ACQUIRE SHARES OUTSTANDING
ON THE DATE OF PURCHASE), (II) ANY REQUISITE WAITING PERIOD UNDER THE
HART-SCOTT-RODINO ANTITRUST IMPROVEMENTS ACT OF 1976, AS AMENDED, APPLICABLE TO
THE PURCHASE OF SHARES PURSUANT TO THE OFFER OR THE MERGER DESCRIBED HEREIN
HAVING BEEN TERMINATED OR HAVING EXPIRED, AND (III) THE APPLICABLE WAITING
PERIODS UNDER CERTAIN FOREIGN ANTITRUST AND COMPETITION LAWS HAVING BEEN
TERMINATED OR HAVING EXPIRED, EXCEPT FOR SUCH WAITING PERIODS THE FAILURE OF
WHICH TO TERMINATE OR EXPIRE IS NOT REASONABLY LIKELY TO HAVE A PARENT MATERIAL
ADVERSE EFFECT OR A COMPANY MATERIAL ADVERSE EFFECT (AS SUCH TERMS ARE DEFINED
IN THE OFFER TO PURCHASE) OR TO PROVIDE A REASONABLE BASIS TO CONCLUDE THAT
PARENT, MERGER SUB OR THE COMPANY OR ANY OF ITS DIRECTORS, OFFICERS, AGENTS,
ADVISORS OR OTHER REPRESENTATIVES WOULD BE SUBJECT TO THE RISK OF CRIMINAL
LIABILITY.
THE OFFER IS BEING MADE PURSUANT TO AN AGREEMENT AND PLAN OF MERGER, DATED
AS OF AUGUST 13, 2000 (THE "MERGER AGREEMENT"), AMONG PARENT, MERGER SUB, AND
THE COMPANY. THE BOARD OF DIRECTORS OF THE COMPANY HAS DETERMINED THAT THE OFFER
AND THE MERGER ARE ADVISABLE AND IN THE BEST INTERESTS OF THE COMPANY'S
STOCKHOLDERS AND UNANIMOUSLY RECOMMENDS THAT THE COMPANY'S STOCKHOLDERS ACCEPT
THE OFFER AND TENDER THEIR SHARES PURSUANT TO THE OFFER.
For your information and for forwarding to your clients for whom you hold
Shares registered in your name or in the name of your nominee, we are enclosing
the following documents:
1. Offer to Purchase dated August 21, 2000;
2. Letter of Transmittal for your use in accepting the Offer and tendering
Shares and for the information of your clients;
3. Notice of Guaranteed Delivery to be used to accept the Offer if
certificates for the Shares and all other required documents cannot be delivered
to Harris Trust Company of New York (the "Depositary"), or if the procedures for
book-entry transfer cannot be completed, by the Expiration Date;
4. A printed form of letter which may be sent to your clients for whose
accounts you hold Shares registered in your name or in the name of your nominee,
with space provided for obtaining such clients' instructions with regard to the
Offer;
5. A letter to stockholders of the Company from Sean P. Lance, President
and Chief Executive Officer of the Company, together with a
Solicitation/Recommendation Statement on Schedule 14D-9 dated August 21, 2000,
which has been filed by the Company with the Securities and Exchange Commission
which includes the recommendation of the Board of Directors of the Company that
stockholders accept the Offer and tender their Shares to Purchaser pursuant to
the Offer;
6. Guidelines of the Internal Revenue Service for Certification of Taxpayer
Identification Number on Substitute Form W-9; and
7. A return envelope addressed to the Depositary.
Upon the terms and subject to the conditions of the Offer (including, if the
Offer is extended or amended, the terms and conditions of any such extension or
amendment), Merger Sub will accept for payment and pay for any Shares which are
validly tendered on or prior to the Expiration Date, or any Subsequent Offering
Period, and not theretofore properly withdrawn, when permitted, when, as and if
Merger Sub gives oral or written notice to the Depositary of Purchaser's
acceptance of such Shares for payment pursuant to the Offer. Payment for any
Shares purchased pursuant to the Offer will in all
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cases be made only after timely receipt by the Depositary of (i) certificates
for the Shares, or timely confirmation of a book-entry transfer of such Shares
into the Depositary's account at The Depository Trust Company, pursuant to the
procedures described in Section 3 of the Offer to Purchase, (ii) a properly
completed and duly executed Letter of Transmittal (or a properly completed and
manually signed facsimile thereof) or an Agent's Message (as defined in the
Offer to Purchase) in connection with a book-entry transfer and (iii) all other
documents required by the Letter of Transmittal.
Merger Sub will not pay any fees or commissions to any broker or dealer or
other person (other than the Depositary, the Information Agent and the Dealer
Manager as described in the Offer to Purchase) in connection with the Offer.
Merger Sub will, however, upon request, reimburse brokers, dealers, commercial
banks and trust companies for customary mailing and handling costs incurred by
them in forwarding the enclosed materials to their customers.
Purchaser will pay or cause to be paid all stock transfer taxes applicable
to its purchase of the Shares pursuant to the Offer, except as otherwise
provided in Instruction 6 of the Letter of Transmittal.
WE REQUEST THAT YOU CONTACT YOUR CLIENTS PROMPTLY. PLEASE NOTE THAT THE
OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON
MONDAY, SEPTEMBER 18, 2000 UNLESS THE OFFER IS EXTENDED.
In order to accept the Offer, a duly executed and properly completed Letter
of Transmittal (or a manually signed facsimile thereof), with any required
signature guarantees, or an Agent's Message in connection with a book-entry
transfer of the Shares, and any other required documents, should be sent to the
Depositary, and certificates representing the tendered Shares should be
delivered or tendered by book-entry transfer, all in accordance with the
Instructions set forth in the Letter of Transmittal and in the Offer to
Purchase.
If holders of the Shares wish to tender, but it is impracticable for them to
forward their certificates or other required documents or to comply with the
procedures for delivery by book-entry transfer prior to the expiration of the
Offer, a tender may be effected by following the guaranteed delivery procedures
specified in Section 3 of the Offer to Purchase.
Any inquiries you may have with respect to the Offer should be addressed to,
and additional copies of the enclosed materials may be obtained from, the
Information Agent or the undersigned at the addresses and telephone numbers set
forth on the back cover of the Offer to Purchase.
Very truly yours,
DONALDSON, LUFKIN & JENRETTE SECURITIES
CORPORATION
NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU THE
AGENT OF PARENT, MERGER SUB, THE COMPANY, THE DEALER MANAGER, THE INFORMATION
AGENT, THE DEPOSITARY, OR ANY AFFILIATE OF ANY OF THE FOREGOING, OR AUTHORIZE
YOU OR ANY OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY STATEMENT ON BEHALF OF
ANY OF THEM IN CONNECTION WITH THE OFFER OTHER THAN THE DOCUMENTS ENCLOSED
HEREWITH AND THE STATEMENTS CONTAINED THEREIN.
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