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                                                                     EXHIBIT 4.5



THIS WARRANT AND THE UNDERLYING SECURITIES HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"). THEY MAY NOT BE SOLD, OFFERED
FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION
STATEMENT AS TO SUCH SECURITIES UNDER THE ACT OR AN OPINION OF COUNSEL
SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

                               ARADIGM CORPORATION

                        WARRANT TO PURCHASE COMMON STOCK

                                                               December 14, 2001

                          VOID AFTER DECEMBER 14, 2006

     THIS CERTIFIES THAT, for value received, ___________________________, with
its principal office at __________________________, or assigns (the "Holder"),
is entitled to subscribe for and purchase at the Exercise Price (defined below)
from Aradigm Corporation, a California corporation, with its principal office at
3929 Point Eden Way, Hayward, CA 94545 (the "Company") up to
____________________ (_____) shares of the Common Stock of the Company (the
"Common Stock").

     1.   DEFINITIONS. As used herein, the following terms shall have the
following respective meanings:

          (a) "Exercise Period" shall mean the period commencing with the date
that is the earlier of (i) the increase in the number of authorized shares of
Common Stock to a number that is sufficient to permit exercise of this Warrant
(the "Common Increase") and (ii) May 31, 2002, and ending five (5) years from
the date hereof, unless sooner terminated as provided below.

          (b) "Exercise Price" shall mean $6.97 per share, subject to adjustment
pursuant to Section 5 below.

          (c) "Exercise Shares" shall mean the shares of the Company's Common
Stock issuable upon exercise of this Warrant.

     2. EXERCISE OF WARRANT. The rights represented by this Warrant may be
exercised in whole or in part at any time during the Exercise Period, by
delivery of the following to the Company at its address set forth above (or at
such other address as it may designate by notice in writing to the Holder):

          (a)  An executed Notice of Exercise in the form attached hereto;

          (b)  Payment of the Exercise Price either (i) in cash or by check, or
(ii) by cancellation of indebtedness; and

          (c)  This Warrant.

                                       1.

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     Upon the exercise of the rights represented by this Warrant, a certificate
or certificates for the Exercise Shares so purchased, registered in the name of
the Holder or persons affiliated with the Holder, if the Holder so designates,
shall be issued and delivered to the Holder within a reasonable time after the
rights represented by this Warrant shall have been so exercised.

     The person in whose name any certificate or certificates for Exercise
Shares are to be issued upon exercise of this Warrant shall be deemed to have
become the holder of record of such shares on the date on which this Warrant was
surrendered and payment of the Exercise Price was made, irrespective of the date
of delivery of such certificate or certificates, except that, if the date of
such surrender and payment is a date when the stock transfer books of the
Company are closed, such person shall be deemed to have become the holder of
such shares at the close of business on the next succeeding date on which the
stock transfer books are open.

     2.1 NET EXERCISE. Notwithstanding any provisions herein to the contrary, if
the fair market value of one share of the Company's Common Stock is greater than
the Exercise Price (at the date of calculation as set forth below), in lieu of
exercising this Warrant by payment of cash, the Holder may elect to receive
shares equal to the value (as determined below) of this Warrant (or the portion
thereof being canceled) by surrender of this Warrant at the principal office of
the Company together with the properly endorsed Notice of Exercise in which
event the Company shall issue to the Holder a number of shares of Common Stock
computed using the following formula:

          X = Y (A-B)
              -------
                 A

     Where X = the number of shares of Common Stock to be issued to the Holder

           Y = the number of shares of Common Stock purchasable under the
               Warrant or, if only a portion of the Warrant is being exercised,
               the portion of the Warrant being canceled (at the date of such
               calculation)

           A = the fair market value of one share of the Company's Common Stock
               (at the date of such calculation)

           B = Exercise Price (as adjusted to the date of such calculation)

     For purposes of the above calculation, the "fair market value" of one share
of Common Stock shall mean (i) the average of the closing sales prices for the
shares of Common Stock on the Nasdaq National Market or other trading market
where such security is listed or traded as reported by Bloomberg Financial
Markets (or a comparable reporting service of national reputation selected by
the Company and reasonably acceptable to the holders if Bloomberg Financial
Markets is not then reporting sales prices of such security) (collectively,
"Bloomberg") for the ten (10) consecutive trading days immediately preceding
such date, or (ii) if the Nasdaq National Market is not the principal trading
market for the shares of Common Stock, the average of the reported sales prices
reported by Bloomberg on the principal trading market for the Common Stock
during the same period, or, if there is no sales price for such period, the last
sales price reported by Bloomberg for such period, or (iii) if neither of the
foregoing applies, the last sales price of such security in the over-the-counter
market on the pink sheets or bulletin board for

                                       2.
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such security as reported by Bloomberg, or if no sales price is so reported for
such security, the last bid price of such security as reported by Bloomberg, or
(iv) if fair market value cannot be calculated as of such date on any of the
foregoing bases, the fair market value shall be as determined by the Board of
Directors of the Company in the exercise of its good faith judgment.

     3. COVENANTS OF THE COMPANY.

     3.1 COVENANTS AS TO EXERCISE SHARES. The Company covenants and agrees that
all Exercise Shares that may be issued upon the exercise of the rights
represented by this Warrant will, upon issuance, be validly issued and
outstanding, fully paid and nonassessable, and free from all taxes, liens and
charges with respect to the issuance thereof. The Company further covenants and
agrees that the Company will at all times during the Exercise Period, have
authorized and reserved, free from preemptive rights, a sufficient number of
shares of its Common Stock to provide for the exercise of the rights represented
by this Warrant. If at any time during the Exercise Period the number of
authorized but unissued shares of Common Stock shall not be sufficient to permit
exercise of this Warrant, the Company will take such corporate action as may, in
the opinion of its counsel, be necessary to increase its authorized but unissued
shares of Common Stock to such number of shares as shall be sufficient for such
purposes. If by May 31, 2002 the number of authorized but unissued shares of
Common Stock shall not be sufficient to permit exercise of this Warrant, then
for each thirty (30) day period following May 31, 2002, until but excluding the
date of the Common Increase, the Company shall, for such period (or prorated for
any partial period), issue to the Holder a warrant to purchase ____________
shares of Common Stock; and for any such period, such warrant shall be issued no
later than the first business day of the calendar month next succeeding the last
month in which such period occurs.

     3.2 NO IMPAIRMENT. Except and to the extent as waived or consented to by
the Holder, the Company will not, by amendment of its Articles of Incorporation
or through any reorganization, transfer of assets, consolidation, merger,
dissolution, issue or sale of securities or any other voluntary action, avoid or
seek to avoid the observance or performance of any of the terms to be observed
or performed hereunder by the Company, but will at all times in good faith
assist in the carrying out of all the provisions of this Warrant and in the
taking of all such action as may be necessary or appropriate in order to protect
the exercise rights of the Holder against impairment.

     3.3 NOTICES OF RECORD DATE. In the event of any taking by the Company of a
record of the holders of any class of securities for the purpose of determining
the holders thereof who are entitled to receive any dividend (other than a cash
dividend which is the same as cash dividends paid in previous quarters) or other
distribution, the Company shall mail to the Holder, at least ten (10) days prior
to the date specified herein, a notice specifying the date on which any such
record is to be taken for the purpose of such dividend or distribution.

     4. REPRESENTATIONS OF HOLDER.

     4.1 ACQUISITION OF WARRANT FOR PERSONAL ACCOUNT. The Holder represents and
warrants that it is acquiring the Warrant solely for its account for investment
and not with a view to or for sale or distribution of said Warrant or any part
thereof. The Holder also represents that

                                       3.

<PAGE>

the entire legal and beneficial interests of the Warrant and Exercise Shares the
Holder is acquiring is being acquired for, and will be held for, its account
only.

     4.2  SECURITIES ARE NOT REGISTERED.

          (a) The Holder understands that the Warrant and the Exercise Shares
have not been registered under the Securities Act of 1933, as amended (the
"Act") on the basis that no distribution or public offering of the stock of the
Company is to be effected. The Holder realizes that the basis for the exemption
may not be present if, notwithstanding its representations, the Holder has a
present intention of acquiring the securities for a fixed or determinable period
in the future, selling (in connection with a distribution or otherwise),
granting any participation in, or otherwise distributing the securities. The
Holder has no such present intention.

          (b) The Holder recognizes that the Warrant and the Exercise Shares
must be held indefinitely unless they are subsequently registered under the Act
or an exemption from such registration is available. The Holder recognizes that
the Company will register the Exercise Shares pursuant to the provisions of
Section 7 of the Securities Purchase Agreement.

          (c) The Holder is aware that neither the Warrant nor the Exercise
Shares may be sold pursuant to Rule 144 adopted under the Act unless certain
conditions are met, including, among other things, the existence of a public
market for the shares, the availability of certain current public information
about the Company, the resale following the required holding period under Rule
144 and the number of shares being sold during any three month period not
exceeding specified limitations.

     4.3  DISPOSITION OF WARRANT AND EXERCISE SHARES.

          (a) The Holder further agrees not to make any disposition of all or
any part of the Warrant or Exercise Shares in any event unless and until:

               (i) The Company shall have received a letter secured by the
Holder from the Securities and Exchange Commission stating that no action will
be recommended to the Commission with respect to the proposed disposition; or

               (ii) There is then in effect a registration statement under the
Act covering such proposed disposition and such disposition is made in
accordance with said registration statement; or

               (iii) The Holder shall have notified the Company of the proposed
disposition and shall have furnished the Company with a detailed statement of
the circumstances surrounding the proposed disposition, and if reasonably
requested by the Company, the Holder shall have furnished the Company with an
opinion of counsel, reasonably satisfactory to the Company, for the Holder to
the effect that such disposition will not require registration of such Warrant
or Exercise Shares under the Act or any applicable state securities laws.

          (b) The Holder understands and agrees that all certificates evidencing
the shares to be issued to the Holder may bear the following legend:

                                       4.

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     "THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
     1933, AS AMENDED (THE "ACT"). THEY MAY NOT BE SOLD, OFFERED FOR SALE,
     PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION
     STATEMENT AS TO THE SECURITIES UNDER THE ACT OR AN OPINION OF COUNSEL
     SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED."

     5.   ADJUSTMENT OF EXERCISE PRICE.

          (a) In the event of changes in the outstanding Common Stock of the
Company by reason of stock dividends, split-ups, recapitalizations,
reclassifications, combinations or exchanges of shares, separations,
reorganizations, liquidations, or the like, the number and class of shares
available under the Warrant in the aggregate and the Exercise Price shall be
correspondingly adjusted to give the Holder of the Warrant, on exercise for the
same aggregate Exercise Price, the total number, class, and kind of shares as
the Holder would have owned had the Warrant been exercised prior to the event
and had the Holder continued to hold such shares until after the event requiring
adjustment. The form of this Warrant need not be changed because of any
adjustment in the number of Exercise Shares subject to this Warrant.

          (b) If at any time or from time to time the holders of Common Stock of
the Company (or any shares of stock or other securities at the time receivable
upon the exercise of this Warrant) shall have received or become entitled to
receive, without payment therefor,

               (i) Common Stock or any shares of stock or other securities which
are at any time directly or indirectly convertible into or exchangeable for
Common Stock, or any rights or options to subscribe for, purchase or otherwise
acquire any of the foregoing by way of dividend or other distribution (other
than a dividend or distribution covered in section 5(a) above),

               (ii) any cash paid or payable otherwise than as a cash dividend,
or

               (iii) Common Stock or additional stock or other securities or
property (including cash) by way of spinoff, split-up, reclassification,
combination of shares or similar corporate rearrangement (other than shares of
Common Stock pursuant to Section 5(a) above),

then and in each such case, the Holder hereof will, upon the exercise of this
Warrant, be entitled to receive, in addition to the number of shares of Common
Stock receivable thereupon, and without payment of any additional consideration
therefor, the amount of stock and other securities and property (including cash
in the cases referred to in clauses (ii) and (iii) above) which such Holder
would hold on the date of such exercise had he been the holder of record of such
Common Stock as of the date on which holders of Common Stock received or became
entitled to receive such shares or all other additional stock and other
securities and property.

     6.   FRACTIONAL SHARES. No fractional shares shall be issued upon the
exercise of this Warrant as a consequence of any adjustment pursuant hereto. All
Exercise Shares (including fractions) issuable upon exercise of this Warrant may
be aggregated for purposes of determining

                                       5.

<PAGE>

whether the exercise would result in the issuance of any fractional share. If,
after aggregation, the exercise would result in the issuance of a fractional
share, the Company shall, in lieu of issuance of any fractional share, pay the
Holder otherwise entitled to such fraction a sum in cash equal to the product
resulting from multiplying the then current fair market value of an Exercise
Share by such fraction.

     7. NO SHAREHOLDER RIGHTS. This Warrant in and of itself shall not entitle
the Holder to any voting rights or other rights as a shareholder of the Company.

     8. TRANSFER OF WARRANT. Subject to applicable laws and the restriction on
transfer set forth on the first page of this Warrant, this Warrant and all
rights hereunder are transferable, by the Holder in person or by duly authorized
attorney, upon delivery of this Warrant and the form of assignment attached
hereto to any transferee designated by Holder. The transferee shall sign an
investment letter in form and substance satisfactory to the Company.

     9. LOST, STOLEN, MUTILATED OR DESTROYED WARRANT. If this Warrant is lost,
stolen, mutilated or destroyed, the Company may, on such terms as to indemnity
or otherwise as it may reasonably impose (which shall, in the case of a
mutilated Warrant, include the surrender thereof), issue a new Warrant of like
denomination and tenor as the Warrant so lost, stolen, mutilated or destroyed.
Any such new Warrant shall constitute an original contractual obligation of the
Company, whether or not the allegedly lost, stolen, mutilated or destroyed
Warrant shall be at any time enforceable by anyone.

     10. NOTICES, ETC. All notices required or permitted hereunder shall be in
writing and shall be deemed effectively given: (a) upon personal delivery to the
party to be notified, (b) when sent by confirmed telex or facsimile if sent
during normal business hours of the recipient, if not, then on the next business
day, (c) five (5) days after having been sent by registered or certified mail,
return receipt requested, postage prepaid, or (d) one (1) day after deposit with
a nationally recognized overnight courier, specifying next day delivery, with
written verification of receipt. All communications shall be sent to the Company
at the address listed on the signature page and to Holder at ___________________
or at such other address as the Company or Holder may designate by ten (10) days
advance written notice to the other parties hereto.

     11. ACCEPTANCE. Receipt of this Warrant by the Holder shall constitute
acceptance of and agreement to all of the terms and conditions contained herein.

     12. GOVERNING LAW. This Warrant and all rights, obligations and liabilities
hereunder shall be governed by the laws of the State of California.

                                       6.

<PAGE>

     IN WITNESS WHEREOF, the Company has caused this Warrant to be executed by
its duly authorized officer as of December 14, 2001.

                                ARADIGM CORPORATION


                                By:
                                    --------------------------------------------

                                Name: Richard P. Thompson

                                Title: President and Chief Executive Officer

                                Address: 3929 Point Eden Way, Hayward, CA  94545

<PAGE>

                               NOTICE OF EXERCISE

TO: ARADIGM CORPORATION

     (1) [ ] The undersigned hereby elects to purchase ________ shares of the
Common Stock of ARADIGM CORPORATION (the "Company") pursuant to the terms of the
attached Warrant, and tenders herewith payment of the exercise price in full,
together with all applicable transfer taxes, if any.

         [ ] The undersigned hereby elects to purchase ________ shares of Common
Stock of the Company pursuant to the terms of the net exercise provisions set
forth in Section 2.1 of the attached Warrant, and shall tender payment of all
applicable transfer taxes, if any.

     (2) Please issue a certificate or certificates representing said shares of
Common Stock of the Company in the name of the undersigned or in such other name
as is specified below:

                            ------------------------
                                     (Name)


                            ------------------------

                            ------------------------
                                    (Address)

     (3) The undersigned represents that (i) the aforesaid shares of Common
Stock are being acquired for the account of the undersigned for investment and
not with a view to, or for resale in connection with, the distribution thereof
and that the undersigned has no present intention of distributing or reselling
such shares, other than as contemplated by Article 7 of the Securities Purchase
Agreement dated as of December 11, 2001 by and among the Company and the
purchasers named therein; (ii) the undersigned is aware of the Company's
business affairs and financial condition and has acquired sufficient information
about the Company to reach an informed and knowledgeable decision regarding its
investment in the Company; (iii) the undersigned is experienced in making
investments of this type and has such knowledge and background in financial and
business matters that the undersigned is capable of evaluating the merits and
risks of this investment and protecting the undersigned's own interests; (iv)
the undersigned understands that the shares of Common Stock issuable upon
exercise of this Warrant have not been registered under the Securities Act of
1933, as amended (the "Securities Act"), by reason of a specific exemption from
the registration provisions of the Securities Act, which exemption depends upon,
among other things, the bona fide nature of the investment intent as expressed
herein, and, because such securities have not been registered under the
Securities Act, they must be held indefinitely unless subsequently registered
under the Securities Act or an exemption from such registration is available;
(v) the undersigned is aware that the aforesaid shares of Common Stock may not
be sold pursuant to Rule 144 adopted under the Securities Act unless certain
conditions are met and until the undersigned has held the shares for the number
of years prescribed by Rule 144, that among the conditions for use of the Rule
is the availability of current information to the public about the Company; and
(vi) the undersigned agrees not to make any disposition of all or any part of
the aforesaid shares of Common Stock unless and until there is then in effect a
registration statement under the Securities Act covering such proposed
disposition and such disposition is made in accordance with said registration

<PAGE>

statement, or the undersigned has provided the Company with an opinion of
counsel satisfactory to the Company, stating that such registration is not
required.


--------------------------------        ----------------------------------------
(Date)                                  (Signature)


                                        ----------------------------------------
                                        (Print name)

<PAGE>

                                 ASSIGNMENT FORM

           (To assign the foregoing Warrant, execute this form and
           supply required information. Do not use this form to
           purchase shares.)


     FOR VALUE RECEIVED, the foregoing Warrant and all rights evidenced thereby
are hereby assigned to

Name:
      --------------------------------------------------------------------------
                                 (Please Print)

Address:
         -----------------------------------------------------------------------
                                 (Please Print)

Dated:            , 20
      ------------    --


Holder's
Signature:
           --------------------------------------

Holder's
Address:
         ----------------------------------------


NOTE: The signature to this Assignment Form must correspond with the name as it
appears on the face of the Warrant, without alteration or enlargement or any
change whatever. Officers of corporations and those acting in a fiduciary or
other representative capacity should file proper evidence of authority to assign
the foregoing Warrant.