================================================================================
Prospectus Supplement
To Prospectus Dated November 28, 2000


                                3,000,000 SHARES

                                    XOMA Ltd.

                                  Common Shares


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

o  We are offering 3,000,000 common shares    o Our common shares are listed
   pursuant to an underwriting agreement        on The Nasdaq  Stock Market
   with the underwriters of this offering.      under the symbol "XOMA." On June
                                                25, 2001, the last reported
                                                sales price of our common shares
                                                on Nasdaq was $15.04 per share.



     This investment involves a high degree of risk. Consider carefully the risk
factors beginning on page 3 of the accompanying prospectus and on page S-3 of
this prospectus supplement before you invest.




                                                             Underwriting Discounts
                                    Price to Public             and Commissions        Proceeds to XOMA Ltd.
                                    ---------------          ----------------------    --------------------
                                                                                       
Per Share..................              $15.00                     $0.5625                     $14.4375
Total......................           $45,000,000                  $1,687,500                  $43,312,500



     Neither the SEC nor any state securities commission has approved these
securities or determined that this prospectus is accurate or complete. Any
representation to the contrary is a criminal offense.


       U.S. Bancorp Piper Jaffray                   CIBC World Markets

         Adams, Harkness & Hill               Arnhold & S. Bleichroeder, Inc.


            The date of this prospectus supplement is June 26, 2001.







                                TABLE OF CONTENTS


                                                          
Risk Factors........................................S-3      Price Range of Common Shares and Dividend
                                                                  Information..................................S-12
Incorporation of Information We File With The                Use of Proceeds...................................S-13
     SEC...........................................S-10      Underwriting......................................S-14
Special Note Regarding Forward-Looking                       Where You Can Get More Information................S-16
     Statements ...................................S-11      Legal Matters.....................................S-17

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


  You should read the information in this prospectus supplement together with
    the information in the accompanying prospectus, including the documents
                           incorporated by reference.



                                      S-2




                                  RISK FACTORS

     You should carefully consider the following factors and other information
in this prospectus supplement and the accompanying prospectus before deciding to
invest in common shares. You should also consider carefully the other
information contained, or incorporated by reference in, this prospectus
supplement or the accompanying prospectus. The risks and uncertainties described
below and elsewhere are not the only ones facing our company and our
shareholders. Additional risks and uncertainties may also adversely impair our
business operations. The actual results of our business could differ materially
from those described as a result of these risk factors. In such case, the
trading price of our common shares could decline, and you may lose all or part
of the money you paid to buy our common shares.

None Of Our Pharmaceutical Products Have Received Regulatory Approval; If Our
Products Do Not Receive Regulatory Approval, Neither We Nor Our Third Party
Collaborators Will Be Able To Manufacture And Market Them

     Even our most developed pharmaceutical product has yet to complete final
clinical testing. We will be unable to manufacture and market our products
without required regulatory approvals in the United States and other countries.
The United States government and governments of other countries extensively
regulate many aspects of our products, including:

     o    testing

     o    manufacturing

     o    promotion and marketing and

     o    exporting.

     In the United States, the Food and Drug Administration regulates
pharmaceutical products under the Federal Food, Drug, and Cosmetic Act and other
laws, including, in the case of biologics, the Public Health Service Act. At the
present time, we believe that our products will be regulated by the FDA as
biologics. State regulations may also affect our proposed products.

     In December 1992, we submitted an investigational new drug application to
the FDA to begin human testing of our NEUPREX(R) product, a
genetically-engineered fragment of a human protein (BPI). We have licensed
worldwide rights to all pharmaceutical compositions containing BPI (including
NEUPREX(R)) for treatment of meningococcemia (a potentially deadly bacterial
infection principally of children) and in substantially all future
anti-bacterial and anti-endotoxin human clinical indications to Baxter
Healthcare Corporation. In April 2000, members of the FDA and representatives of
XOMA and Baxter discussed results from the Phase III trial that tested
NEUPREX(R) in pediatric patients with severe meningococcemia, and senior
representatives of the FDA indicated that the data presented were not sufficient
to support the filing of an application for marketing approval at that time. We
and Baxter are therefore examining ways to supply additional data necessary to
proceed with the filing. We cannot confirm that we will be able to supply such
additional data. If we conduct an additional trial, we cannot assure you that
the results will be adequate for approval. In September 1999, we discontinued
patient enrollment in our Phase III clinical trial testing NEUPREX(R) in trauma
patients with severe blood loss because an independent data safety monitoring
board told us that interim results from the trial did not support continuing the
trial. We have conducted earlier stage clinical trials testing NEUPREX(R) as a
treatment in three additional indications:

     o    prevention of complications following partial hepatectomy (a type of
          major liver surgery)

     o    treatment of severe infections within the abdomen in combination with
          antibiotics and


                                      S-3


     o    treatment of cystic fibrosis patients (whose genetic disorder
          predisposes them to recurring bacterial lung infections).

Baxter has filed an investigational new drug application with the FDA to study
NEUPREX(R) in Crohn's disease patients. We continue to evaluate with Baxter
alternatives regarding additional indications. We cannot predict that results
will support product approval or justify further development.

     In September 1996, XOMA and Genentech, Inc. announced that an
investigational new drug application had been filed with the FDA for clinical
testing of Xanelim(TM) (falizumeb) in patients with moderate to severe
psoriasis. We completed a Phase II efficacy study in Canada in psoriasis
patients in late 1998, subsequently received a $2 million milestone payment from
Genentech, and agreed with Genentech to continue collaborative development of
the product in psoriasis through Phase III and to expand the program to include
all indications for the product. In May 2001, XOMA and Genentech announced
preliminary positive results from the initial 12-week treatment periods of two
Phase III pivotal trials of Xanelim(TM) in patients with moderate to severe
plaque psoriasis. XOMA has also initiated and completed enrollment in a Phase
I/II study of Xanelim(TM) in kidney transplant recipients.

     In November 2000, we initiated a Phase I study in cancer patients of ING-1,
a high-affinity antibody to an antigen expressed on epithelial cell cancers
(breast, colorectal, prostate and others) that is designed to destroy cancer
cells by recruiting the patient's own immune system.

     Our other potential products will also require significant additional
development, including extensive preclinical and clinical testing.

     The FDA has substantial discretion in both the product approval process and
manufacturing facility approval process and we cannot predict at what point, or
whether, the FDA will be satisfied with our submissions or whether the FDA will
raise questions which may be material and delay or preclude product approval or
manufacturing facility approval. As we accumulate additional clinical data, we
will submit it to the FDA, which may have a material impact on the FDA product
approval process.

     Given that regulatory review is an interactive and continuous process, we
maintain a policy of limiting announcements and comments upon the specific
details of the ongoing regulatory review of our products, subject to our
obligations under the securities laws, until definitive action is taken.

Because All Of Our Products Are Still In Development, We Will Require
Substantial Funds To Continue; We Cannot Be Certain That Funds Will Be Available
And, If Not Available, We May Have To Take Actions Which Could Adversely Affect
Your Rights

     If adequate funds are not available, we may have to dilute or otherwise
adversely affect the rights of existing shareholders, curtail or cease
operations or, in extreme circumstances, file for bankruptcy protection. We have
spent, and we expect to continue to spend, substantial funds in connection with:

     o    research and development relating to our products and production
          technologies

     o    scale-up of our production capabilities

     o    extensive human clinical trials and

     o    protection of our intellectual property.

We believe that, after giving effect to the proceeds of this offering, we have
enough cash (including interest income) to meet our currently anticipated needs
for operating expenses, working capital, equipment acquisi-



                                      S-4


tions and current research projects through approximately the middle of 2004.
However, to the extent we experience changes in the timing or size of
expenditures or unanticipated expenditures, these funds may not prove adequate
for this period. We continue to evaluate strategic alliances, potential
partnerships and financing arrangements which would further strengthen our
competitive position and provide additional funding. Accordingly, we cannot
assure you that:

     o    operations will generate meaningful funds

     o    additional agreements for product development funding can be reached

     o    strategic alliances can be negotiated or

     o    adequate additional financing will be available for us to finance our
          own development on acceptable terms, if at all.

Cash balances and operating cash flow are influenced primarily by the timing and
level of payments by the Company's licensees and development partners, as well
as by the Company's operating costs.

Because All Of Our Products Are Still In Development, We Have Sustained Losses
In The Past And We Expect To Sustain Losses In The Future

     We have experienced significant losses and, as of March 31, 2001, we had an
accumulated deficit of approximately U.S.$487.2 million.

     For the year ended December 31, 2000 and the three months ended March 31,
2001, we had net losses of approximately U.S.$29.4 million, or U.S.$0.45 per
common share (basic and diluted), and U.S.$7.6 million, or U.S.$0.11 per common
share (basic and diluted), respectively. We expect to incur additional losses in
the future. Our ability to make profits is dependent in large part on obtaining
regulatory approval for our products and entering into agreements for product
development and commercialization, both of which are uncertain. Our ability to
fund our ongoing operations is dependent on the foregoing factors and on our
ability to secure additional funds. We cannot assure you that we will ever make
a profit or that cash flow from future operations will be sufficient to meet our
needs.

If Third Party Collaborators Do Not Successfully Develop and Market Our
Products, We May Not Be Able To Do So On Our Own

     Our financial resources and our marketing experience and expertise are
limited. Consequently, we depend to a large extent upon securing the financial
resources and marketing capabilities of third parties with whom we collaborate.
In April 1996, XOMA and Genentech entered into an agreement whereby XOMA agreed
to co-develop Genentech's humanized monoclonal antibody product Xanelim(TM). In
April 1999, the companies extended and expanded the agreement. In January 2000,
we licensed the worldwide rights to all pharmaceutical compositions containing
BPI (including NEUPREX(R)) for treatment of meningococcemia and substantially
all future anti-bacterial and anti-endotoxin human clinical indications to
Baxter Healthcare Corporation. We cannot assure you that Genentech or Baxter
will successfully develop or market any products.

     Even when we have a collaboration relationship, we cannot assure you that
it will result in successful development of marketable products. For example, in
June 1999, we licensed certain genetically-engineered fragments of BPI to
Allergan Inc. to use in combination with other anti-infectives in products to
treat bacterial ophthalmic infections. In May 2000, following successful product
testing at Allergan, we expanded the collaboration to include "stand-alone"
formulations of BPI and to cover eye infections caused by any microbes. In
November 2000, Allergan advised us that for internal economic reasons they
planned to discontinue development of BPI-derived ophthalmic anti-infective
products. We cannot assure you that we will succeed in



                                      S-5


finding another licensee for these products or that any such licensee will be
successful in developing and marketing the products.

     As of the date of this prospectus, we have not entered into any other
license agreements regarding our other products currently in development.
Although we continue to evaluate additional strategic alliances and potential
partnerships, we cannot predict whether or when any such alliances or
partnerships will be entered into.

If Any Of Our Products Receives Regulatory Approval, We May Not Be Able To
Increase Existing Or Acquire New Manufacturing Capacity Sufficient To Meet
Market Demand

     We have never commercially introduced any pharmaceutical products. We
cannot assure you that the capacity of our existing manufacturing facilities can
be increased to produce sufficient quantities of our products to meet market
demand. Also, if we need additional manufacturing facilities to meet market
demand, we cannot assure you that we will successfully obtain those facilities.

If Our Patent Protection For Our Principal Products and Processes Is Not
Enforceable, We Will Not Realize Our Profit Potential

     Because of the length of time and the expense associated with bringing new
products to the marketplace, we hold and are in the process of applying for a
number of patents in the United States and abroad to protect our products and
important processes and also have obtained or have the right to obtain exclusive
licenses to certain patents and applications filed by others. However, the
patent position of biotechnology companies generally is highly uncertain, and no
consistent policy regarding the breadth of allowed claims has emerged from the
actions of the U.S. Patent and Trademark Office with respect to biotechnology
patents. Legal considerations surrounding the validity of biotechnology patents
continue to be in transition, and we cannot assure you that historical legal
standards surrounding questions of validity will continue to be applied or that
current defenses as to issued biotechnology patents will in fact be considered
substantial in the future. Accordingly, we cannot assure you as to:

     o    the degree and range of protection any patents will afford against
          competitors with similar technologies

     o    if and when patents will issue

     o    whether or not others will obtain patents claiming aspects similar to
          those covered by our patent applications or

     o    the extent to which we will be successful in avoiding infringement of
          any patents granted to others.

     The Patent Office has issued and/or allowed 53 patents to us related to our
BPI-based products, including novel compositions, their manufacture,
formulation, assay and use. In addition, we are the exclusive licensee of
BPI-related patents and applications owned by New York University and Incyte
Pharmaceuticals Inc. The Patent Office has also issued and/or allowed nine
patents to us related to our bacterial expression technology.

     If certain patents issued to others are upheld or if certain patent
applications filed by others issue and are upheld, we may require licenses from
others in order to develop and commercialize certain potential products
incorporating our technology or we may become involved in litigation to
determine the proprietary rights of others. We cannot assure you that these
licenses, if required, will be available on acceptable terms or that such
litigation will not be costly or will not have other adverse effects on our
business.



                                      S-6


     We may be required to engage in litigation or other proceedings to protect
our intellectual property. We are currently engaged in litigation with Biosite
Diagnostics Incorporated regarding certain license agreements relating to our
expression technology. We cannot assure you that proceedings of this type will
not be costly or will not have other adverse effects on our business.

     Due to the uncertainties regarding biotechnology patents, we also have
relied and will continue to rely upon trade secrets, know-how and continuing
technological advancement to develop and maintain our competitive position. All
of our employees have signed confidentiality agreements under which they have
agreed not to use or disclose any of our proprietary information. Research and
development contracts and relationships between us and our scientific
consultants and potential customers provide access to aspects of our know-how
that are protected generally under confidentiality agreements. We cannot assure
you that these confidentiality agreements will be honored or are enforceable. To
the extent proprietary information is divulged to competitors or to the public
generally, such disclosure may have a material adverse effect on our ability to
develop or commercialize our products.

Other Companies May Render Some Or All Of Our Products Noncompetitive Or
Obsolete

     We cannot assure you that developments by others will not render our
products or technologies obsolete or uncompetitive. Technologies developed and
utilized by the biotechnology and pharmaceutical industries are continuously and
substantially changing. Competition in the areas of genetically-engineered
DNA-based and antibody-based technologies is intense and expected to increase in
the future as a number of established biotechnology firms and large chemical and
pharmaceutical companies advance in these fields. Many of these competitors may
be able to develop products and processes competitive with or superior to our
own for many reasons, including that they may have:

     o    significantly greater financial resources

     o    larger research and development and marketing staffs

     o    larger production facilities

     o    entered into arrangements with, or acquired, biotechnology companies
          to enhance their capabilities or

     o    extensive experience in preclinical testing and human clinical trials.

     These factors may enable others to develop products and processes
competitive with or superior to our own. In addition, a significant amount of
research in biotechnology is being carried out in universities and other
non-profit research organizations. These entities are becoming increasingly
interested in the commercial value of their work and may become more aggressive
in seeking patent protection and licensing arrangements.

     It is possible that one or more other companies may be developing one or
more products based on BPI, and we cannot assure you that these product(s) will
not prove to be more effective than NEUPREX(R).

     Without limiting the foregoing, XOMA is aware that Biogen Inc. has
announced completion of Phase III testing of its Amevive(TM) product in chronic
plaque psoriasis, Centocor Inc., a unit of Johnson & Johnson, is testing its
rheumatoid arthritis and Crohn's disease drug in Phase II trials in psoriasis,
Immunex Corp. may be testing its rheumatoid arthritis drug in psoriasis and
other companies are developing monoclonal antibody or other products for
treatment of inflammatory skin disorders. In particular, Biogen has announced
that Amevive(TM) achieved positive results in two Phase III clinical trials in
patients with moderate to severe plaque psoriasis and that it will file for
approval of Amevive(TM) by the FDA in the U.S. and the EMEA in Europe in the
second half of this year.



                                      S-7


If We Do Business Internationally, We Will Be Subject To Additional Political,
Economic and Regulatory Uncertainties

     We cannot assure you that we will be able to successfully operate in any
foreign market. We believe that, because the pharmaceutical industry is global
in nature, international activities will be a significant part of our future
business activities and that, when and if we are able to generate income, a
substantial portion of that income will be derived from product sales and other
activities outside the United States. Foreign regulatory agencies often
establish standards different from those in the United States, and an inability
to obtain foreign regulatory approvals on a timely basis could have an adverse
effect on our business. International operations may be limited or disrupted by:

     o    imposition of government controls

     o    export license requirements

     o    political or economic instability

     o    trade restrictions

     o    changes in tariffs

     o    restrictions on repatriating profits

     o    taxation and

     o    difficulties in staffing and managing international operations.

     Also, our business may be adversely affected by fluctuations in currency
exchange rates.

Because We Are A Relatively Small Biopharmaceutical Company With Limited
Resources, We May Not Be Able To Attract And Retain Qualified Personnel, And The
Loss Of Key Personnel Could Delay Or Prevent Achieving Our Objectives

     Our success in developing marketable products and achieving a competitive
position will depend, in part, on our ability to attract and retain qualified
scientific and management personnel, particularly in areas requiring specific
technical, scientific or medical expertise. There is intense competition for
such personnel, and we cannot assure you that we will be able to attract or
retain them. Our research, product development and business efforts would be
adversely affected by the loss of one ore more of key members of our scientific
or management staff.

Because We Engage In Human Testing, We Are Exposed To An Increased Risk Of
Product Liability Claims, Which Would Have An Adverse Effect On Our Business

     The testing and marketing of medical products entails an inherent risk of
allegations of product liability. We believe that we currently have adequate
levels of insurance for our clinical trials; however, we cannot assure you that,
in the event of one ore more large awards, such levels will provide adequate
coverage. We will seek to obtain additional insurance, if needed, if and when
our products are commercialized; however, we cannot assure you that adequate
insurance coverage will be available or be available at acceptable costs or that
a product liability claim would not materially adversely affect our business.



                                      S-8


Our Shareholder Rights Agreement Or Bye-laws May Prevent Transactions That Could
Be Beneficial To Our Shareholders

     Our shareholder rights agreement could make it considerably more difficult
or costly for a person or group to acquire control of XOMA in a transaction that
our board of directors opposes.

     Our bye-laws:

     o    require certain procedures to be followed and time periods to be met
          for any shareholder to propose matters to be considered at annual
          meetings of shareholders, including nominating directors for election
          at those meetings;

     o    authorize our board of directors to issue up to 1,000,000 preference
          shares without shareholder approval and to set the rights, preferences
          and other designations, including voting rights, of those shares as
          the board of directors may determine; and

     o    contain provisions, similar to those contained in the Delaware General
          Corporation Law, that may make business combinations with interested
          shareholders more difficult.

     These provisions of our shareholders rights agreement and our bye-laws,
alone or in combination with each other, may discourage transactions involving
actual or potential changes of control, including transactions that otherwise
could involve payment of a premium over prevailing market prices to holders of
common shares, or could limit the ability of shareholders to approve
transactions that they may deem to be in their best interests.

Because We Have No History Of Profitability And Because The Biotechnology Sector
Has Been Characterized By Highly Volatile Stock Prices, Announcements We Make
And General Market Conditions For Biotechnology Stocks Could Result In A Sudden
Change In The Value Of Our Stock

     As a biopharmaceutical company, we have experienced significant volatility
in our common shares. Fluctuations in our operating results and general market
conditions for biotechnology stocks could have a significant impact on the
volatility of our common share price. From July 1, 2000 through June 25, 2001,
our share price has ranged from a low of U.S. $4.00 to a high of U.S. $16.50. On
June 25, 2001 the last reported sale price of the common shares as reported on
The Nasdaq Stock Market was U.S. $15.04 per share. Factors contributing to such
volatility include:

     o    results of preclinical studies and clinical trials,

     o    evidence of the safety or efficacy of our products,

     o    announcements of new collaborations,

     o    failure to enter into collaborations,

     o    developments in existing collaborations,

     o    our funding requirements and the terms of our financing arrangements,

     o    announcements of technological innovations or new indications for our
          therapeutic products,

     o    government regulations,



                                      S-9


     o    developments in patent or other proprietary rights,

     o    the number of shares outstanding,

     o    the number of shares trading on an average trading day,

     o    announcements regarding other participants in the biotechnology and
          pharmaceutical industries, and

     o    market speculation regarding any of the foregoing.

If You Were To Obtain A Judgment Against Us, It May Be Difficult To Enforce
Against Us Because We Are A Foreign Entity

     We are a Bermuda company. All or a substantial portion of our assets may be
located outside the United States. As a result, it may be difficult for
investors to enforce in United States courts judgments obtained against us. We
have irrevocably agreed that we may be served with process with respect to
actions based on offers and sales of securities made hereby in the United States
by serving Christopher J. Margolin, c/o XOMA Ltd., 2910 Seventh Street,
Berkeley, California 94710, our United States agent appointed for that purpose.
XOMA has been advised by its Bermuda counsel, Conyers Dill & Pearman, that there
is doubt as to whether Bermuda courts would enforce judgments of United States
courts obtained in (a) actions against such persons or XOMA that are predicated
upon the civil liability provisions of the Securities Act or (b) original
actions brought in Bermuda against XOMA or such persons predicated upon the
Securities Act. There is no treaty in effect between the United States and
Bermuda providing for such enforcement, and there are grounds upon which Bermuda
courts may not enforce judgments of United States courts. Certain remedies
available under the United States federal securities laws may not be allowed in
Bermuda courts as contrary to that nation's policy.

                INCORPORATION OF INFORMATION WE FILE WITH THE SEC

     The following documents filed by XOMA with the SEC pursuant to the
Securities Exchange Act are "incorporated by reference" in this prospectus
supplement, which means we can disclose important information to you by
referring you to these documents and they are considered to be a part of this
prospectus supplement:

(1)  annual report on Form 10-K for the fiscal year ended December 31, 2000
     (file no. 000-26169);

(2)  quarterly report on Form 10-Q for the quarterly period ended March 31, 2001
     (file no. 000-26169);

(3)  current report on Form 8-K dated and filed January 30, 2001, as amended by
     an amendment on Form 8-K/A dated and filed on February 13, 2001 (file no.
     0-14710); and

(4)  the description of the common shares in the registration statement on Form
     8-A dated and filed on May 21, 1999 under Section 12 of the Securities
     Exchange Act, including any amendment or report for the purpose of updating
     such description (registration no. 333-68045).

     All documents filed by XOMA with the SEC pursuant to Section 13(a), 13(c),
14 or 15(d) of the Securities Exchange Act after the date of this prospectus
supplement and before all of the common shares offered by this prospectus
supplement have been sold are deemed to be incorporated by reference in, and to
be part of, this prospectus supplement from the date any such document is filed.

     Any statements contained in a document incorporated by reference in this
prospectus supplement are deemed to be modified or superseded for purposes of
this prospectus supplement to the extent that a statement contained in this
prospectus supplement (or in any other subsequently filed document which also is
incorporated



                                      S-10


by reference in this prospectus supplement) modifies or supersedes such
statement. Any statement so modified or superseded is not deemed to constitute a
part of this prospectus supplement except as so modified or superseded.




                                      S-11



                SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

     Some of the statements made in this prospectus supplement are
forward-looking in nature, including those relating to the sufficiency of our
cash position, the FDA regulatory process, timing and results of clinical trials
and other aspects of product development, strategic collaborative relationships
and other statements that are not historical facts. The words "believe," "plan,"
"intend," "expect" and similar expressions are intended to identify
forward-looking statements. We caution you not to place undue reliance on these
forward-looking statements. They apply only as of the date of this prospectus
supplement or the accompanying prospectus, as the case may be, except that
statements incorporated by reference from previously filed reports apply as of
the date made. The occurrence of the events described, and the achievement of
the intended results, depend on many events, some or all of which are not
predictable or not within our control. Actual results may differ materially from
those anticipated in any forward-looking statements. Many risks and
uncertainties are inherent in the biopharmaceutical industry. Others are more
specific to our business. Many of the significant risks related to our business
are described in this prospectus. These include, among others, risks associated
with technology and product development, sufficiency and availability of funds,
marketing risks, patent and intellectual property matters, regulatory and
manufacturing issues and risks associated with competition from other companies.
Many of these risks are discussed further in "Risk Factors." We undertake no
obligation to publicly update any forward-looking statements, regardless of any
new information, future events or other occurrences. We advise you, however, to
consult any additional disclosures we make in our reports to the SEC on Forms
10-K, 10-Q and 8-K.

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

     We have not authorized any dealer, salesperson or other person to give you
written information other than this prospectus supplement or to make
representations as to matters not stated in this prospectus supplement. You must
not rely on unauthorized information. This prospectus supplement is not an offer
to sell these common shares or our solicitation of your offer to buy the common
shares in any jurisdiction where that would not be permitted or legal. Neither
the delivery of this prospectus nor any sales made hereunder after the date of
this prospectus supplement should imply that the information contained in this
prospectus or the affairs of XOMA have not changed since the date of this
prospectus supplement.




                                      S-12



              PRICE RANGE OF COMMON SHARES AND DIVIDEND INFORMATION

     XOMA's common shares (such common shares and the common stock of our
predecessor Delaware corporation are referred to in this prospectus as the
common shares) trade on the Nasdaq National Market under the symbol "XOMA." The
following table sets forth the quarterly range of high and low reported sale
prices of the common shares on the Nasdaq National Market for the periods
indicated (in United States dollars):

                                                        High            Low

1999:
             First Quarter                           $4 3/16         $2 13/16
             Second Quarter                            6 3/4            2 1/2
             Third Quarter                                 8           2 1/32
             Fourth Quarter                            3 3/4                2

2000:
             First Quarter                               $16           $2 3/4
             Second Quarter                           10 1/8            3 1/8
             Third Quarter                            14 3/4                4
             Fourth Quarter                           15 1/4            7 3/4

2001:
             First Quarter                           $13 7/8          $6 1/32
             Second Quarter (through June 25)         16 1/2           5 5/16

     On June 25, 2001 the last reported sale price of the common shares as
reported on The Nasdaq Stock Market was U.S. $15.04 per share.

     XOMA has not paid dividends on its common equity. XOMA currently does not
intend to pay dividends and intends to retain any earnings for use in its
business and the financing of its capital requirements for the foreseeable
future. The payment of any future cash dividends on XOMA's common shares will
necessarily be dependent upon the earnings and financial needs of XOMA, along
with applicable legal and contractual restrictions.




                                      S-13




                                 USE OF PROCEEDS

     We intend to use the net proceeds from this offering for general corporate
purposes, including current research and development projects, the development
of new products or technologies, equipment acquisitions, general working capital
and operating expenses.

     We have not determined the amounts we plan to spend on any of the areas
listed above or the timing of these expenditures. As a result, our management
will have broad discretion to allocate the net proceeds from this offering.
Pending application of the net proceeds as described above, we intend to invest
the net proceeds of the offering in short-term, investment-grade,
interest-bearing securities.




                                      S-14





                                  UNDERWRITING

     Under the terms and subject to the conditions contained in an underwriting
agreement dated June 26, 2001, we have agreed to sell to the underwriters named
below the following respective numbers of common shares:

                                                               Number of
                            Underwriter                         Shares
                            -----------                         ------

     U.S. Bancorp Piper Jaffray                               1,335,000

     CIBC World Markets Corp.                                  999,000

     Adams, Harkness & Hill                                    333,000

     Arnhold & S. Bleichroeder, Inc.                           333,000

                           Total:                            300,000,000

     The underwriting agreement provides that the underwriters are obligated to
purchase all the foregoing common shares in the offering if any are purchased.
The underwriting agreement also provides that if an underwriter defaults, the
purchase commitments of non-defaulting underwriters may be increased or the
offering may be terminated. In addition, the obligation of the underwriters to
purchase the foregoing common shares are subject to certain conditions, as set
forth in the underwriting agreement, and if all of those conditions are not
satisfied, the offering may be terminated.

     The underwriters propose to offer the common shares initially at the public
offering price on the cover page of this prospectus. After the public offering
the underwriters may change the public offering price and concession and
discount to broker/dealers.

     We have agreed that we will not offer, sell, contract to sell, pledge or
otherwise dispose of, directly or indirectly, or file with the Securities and
Exchange Commission a registration statement under the Securities Act relating
to, any shares of our common stock or securities convertible into or
exchangeable or execrable for any shares of our common stock, or publicly
disclose the intention to make any offer, sale, pledge, disposition or filing,
without the prior written consent of the underwriters for a period of 90 days
after the date of this prospectus supplement, except issuances of common stock
pursuant to the conversion or exchange of convertible or exchangeable securities
or the exercise of warrants or options, in each case outstanding on the date
hereof, grants of employee stock options pursuant to the terms of a plan in
effect on the date hereof or issuances of common stock pursuant to the exercise
of such options.

     We have agreed to indemnify the underwriters against liabilities under the
amended Securities Act of 1933 or contribute to payments that the underwriters
may be required to make in that respect.

     The shares of common stock are listed on the NASDAQ National Market under
the symbol "XOMA".

     Certain of the underwriters and their affiliates have engaged and may
engage in commercial and investment banking transactions with us in the ordinary
course of their business. Certain of the underwriters and their affiliates also
provide, or have provided, advisory and other financial services to us. They
have received



                                      S-15


customary fees and expenses for these commercial and investment banking
transactions and for these advisory and other financial services.

     In connection with the offering the underwriters may engage in stabilizing
transactions, syndicate covering transactions, penalty bids and passive market
making in accordance with Regulation M under the amended Securities Exchange Act
of 1934.

o    Stabilization transactions permit bids to purchase the underlying security
     so long as the stabilizing bids do not exceed a specified maximum.

o    Syndicate covering transactions involve purchases of the common stock in
     the open market after the distribution has been completed in order to cover
     syndicate short positions. In determining the source of shares to close out
     the short position, the underwriters will consider, among other things, the
     price of shares available for purchase in the open market as compared to
     the price at which they may purchase shares through the over-allotment
     option. If the underwriters sell more shares than could be covered by the
     over-allotment option, a naked short position, the position can only be
     closed out by buying shares in the open market. A naked short position is
     more likely to be created if the underwriters are concerned that there
     could be downward pressure on the price of the shares in the open market
     after pricing that could adversely affect investors who purchase in the
     offering.

o    Penalty bids permit the representative to reclaim a selling concession from
     a syndicate member when the common shares originally sold by the syndicate
     member is purchased in a stabilizing or syndicate covering transaction to
     cover syndicate short positions.

o    In passive market making, market makers in the common stock who are
     underwriters or prospective underwriters may subject to limitations, make
     bids for or purchases of our common stock until the time, if any, at which
     a stabilizing bid is made.

     These stabilizing transactions, penalty bids, and syndicate covering
transactions may have the effect of raising or maintaining the market price of
our common stock or preventing or retarding a decline in the market price of
common stock. As a result the price of our common stock may be higher than the
price that might otherwise exist in the open market. These transactions may be
effected on the NASDAQ National Market or otherwise and, if commenced, may be
discontinued at any time.

     A prospectus in electronic format may be made available on the web sites
maintained by one or more of the underwriters participating in this offering.
The representatives may agree to allocate a number of shares to underwriters for
sale to their online brokerage account holders. Internet distributions will be
allocated by the underwriters that will make Internet distributions on the same
basis as other allocations.




                                      S-16





                       WHERE YOU CAN GET MORE INFORMATION

     This prospectus supplement is part of a registration statement that we have
filed with the SEC. The registration statement contains exhibits and other
information not included in this prospectus supplement or the accompanying
prospectus. At your request, we will provide you, without charge, a copy of any
documents incorporated by reference in, or included as exhibits to, our
registration statement. If you would like more information, write or call us at:

                                    XOMA Ltd.
                               2910 Seventh Street
                               Berkeley, CA 94710
                            Telephone: (510) 644-1170

     XOMA files annual, quarterly and current reports, proxy statements and
other information with the SEC. You may read and copy any reports, statements
and other information we file at the SEC's public reference room at 450 Fifth
Street, N.W., Washington D.C. 20549. You can request copies of these documents,
upon payment of a duplicating fee, by writing to the SEC. Please call the SEC at
1-800-SEC-0330 for further information on the operation of the public reference
rooms. XOMA's SEC filings are also available to the public on the SEC Internet
site at http://www.sec.gov.

                                  LEGAL MATTERS

     Certain legal matters will be being passed upon for the Company by Conyers
Dill & Pearman, Hamilton, Bermuda; Christopher J. Margolin, General Counsel of
the Company; and Cahill Gordon & Reindel, New York, New York. Certain legal
matters will be passed upon for the Underwriters by Solomon, Zauderer,
Ellenhorn, Frischer & Sharp, New York, New York.



                                      S-17




================================================================================
Prospectus
                                    XOMA Ltd.
                                  Common Shares

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


o We may from time to time issue up to      o  We may sell these common shares
  10,000,000 common shares. We will            to or through underwriters and
  specify in the accompanying prospectus       also to other purchasers or
  supplement the terms of any such             through agents. We will set forth
  offering.                                    the names of any underwriters or
                                               agents in theaccompanying
                                               prospectus supplement.


     This investment involves a high degree of risk. Consider carefully the risk
factors beginning on page 4 of this prospectus before you invest.

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

     Neither the SEC nor any state securities commission has approved these
securities or determined that this prospectus is accurate or complete. Any
representation to the contrary is a criminal offense.

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

                The date of this prospectus is November 28, 2000.









                                TABLE OF CONTENTS


                                                         
About This Prospectus............................   2       Use of Proceeds..................................  14
Risk Factors.....................................   3       Description of Share Capital.....................  15
Incorporation of Information We File                        Plan of Distribution.............................  18
   with the SEC..................................  10       Legal Opinion....................................  19
Special Note Regarding Forward-Looking                      Experts..........................................  19
   Statements....................................  11       Where You Can Get More Information...............  19
XOMA.............................................  12
Price Range of Common Shares and Dividend
   Information...................................  13



                                       2




                              ABOUT THIS PROSPECTUS

     This prospectus is part of a registration statement that we filed with the
Securities and Exchange Commission, or SEC, utilizing a "shelf" registration
process. Under this shelf process, we may sell up to 10,000,000 common shares.
Each time we sell common shares, we will provide a prospectus supplement that
will contain specific information about the terms of that offering.




                                       3



                                  RISK FACTORS

     You should carefully consider the following factors and other information
in this prospectus before deciding to invest in common shares.

None Of Our Pharmaceutical Products Have Received Regulatory Approval; If Our
Products Do Not Receive Regulatory Approval, Neither We Nor Our Third Party
Collaborators Will Be Able To Manufacture And Market Them

     Even our most developed pharmaceutical product has yet to complete final
clinical testing. We will be unable to manufacture and market our products
without required regulatory approvals in the United States and other countries.
The United States government and governments of other countries extensively
regulate many aspects of our products, including:

     o    testing

     o    manufacturing

     o    promotion and marketing and

     o    exporting.

     In the United States, the Food and Drug Administration regulates
pharmaceutical products under the Federal Food, Drug, and Cosmetic Act and other
laws, including, in the case of biologics, the Public Health Service Act. At the
present time, we believe that our products will be regulated by the FDA as
biologics. State regulations may also affect our proposed products.

     In December 1992, we submitted an investigational new drug application to
the FDA to begin human testing of our NEUPREX(R) product, a
genetically-engineered fragment of a human protein (BPI). In April 2000, members
of the FDA and representatives of XOMA and Baxter Healthcare Corporation, to
whom we have licensed worldwide rights to all pharmaceutical compositions
containing BPI (including NEUPREX(R)) for treatment of meningococcemia and in
substantially all future anti-bacterial and anti-endotoxin human clinical
indications, discussed results from the Phase III trial that tested NEUPREX(R)
in pediatric patients with severe meningococcemia (a potentially deadly
bacterial infection principally of children), and senior representatives of the
FDA indicated that the data presented were not sufficient to support the filing
of an application for marketing approval at that time. We and Baxter are
therefore examining ways to supply additional data necessary to proceed with the
filing. We cannot confirm that we will be able to supply such additional data.
If we conduct an additional trial, we cannot assure you that the results will be
adequate for approval. In September 1999, we discontinued patient enrollment in
our Phase III clinical trial testing NEUPREX(R) in trauma patients with severe
blood loss because an independent data safety monitoring board told us that
interim results from the trial did not support continuing the trial. We have
conducted earlier stage clinical trials testing NEUPREX(R) as a treatment in
three additional indications:

     o    prevention of complications following partial hepatectomy (a type of
          major liver surgery)

     o    treatment of severe infections within the abdomen in combination with
          antibiotics and

     o    treatment of cystic fibrosis patients (whose genetic disorder
          predisposes them to recurring bacterial lung infections).



                                       4


We are currently evaluating with Baxter alternatives regarding future
indications. Should we decide to conduct trials in such future indications, we
cannot predict that the results will support product approval or justify further
development.

     In September 1996, XOMA and Genentech, Inc. announced that an
investigational new drug application had been filed with the FDA for clinical
testing of anti-CD11a in patients with moderate to severe psoriasis. We
completed a Phase II efficacy study in Canada in psoriasis patients in late
1998, subsequently received a $2 million milestone payment from Genentech, and
agreed with Genentech to continue collaborative development of the product in
psoriasis through Phase III and to expand the program to include all indications
for the product. Genentech has subsequently completed enrollment in two Phase
III trials of anti-CD11a in psoriasis and XOMA has initiated and completed
enrollment in a Phase I/II study of anti-CD11a in kidney transplant recipients.

     In November 2000, we initiated a Phase I study in cancer patients of ING-1,
a high-affinity antibody to an antigen expressed on epithelial cell cancers
(breast, colorectal, prostate and others) that destroys cancer cells by
recruiting the patient's own immune system.

     Our other potential products will also require significant additional
development, including extensive preclinical and clinical testing.

     The FDA has substantial discretion in both the product approval process and
manufacturing facility approval process and we cannot predict at what point, or
whether, the FDA will be satisfied with our submissions or whether the FDA will
raise questions which may be material and delay or preclude product approval or
manufacturing facility approval. As we accumulate additional clinical data, we
will submit it to the FDA, which may have a material impact on the FDA product
approval process.

     Given that regulatory review is an interactive and continuous process, we
maintain a policy of limiting announcements and comments upon the specific
details of the ongoing regulatory review of our products, subject to our
obligations under the securities laws, until definitive action is taken.

Because All Of Our Products Are Still In Development, We Will Require
Substantial Funds To Continue; We Cannot Be Certain That Funds Will Be
Available And, If Not Available, We May Have To Take Actions Which Could
Adversely Affect Your Rights

     If adequate funds are not available, we may have to dilute or otherwise
adversely affect the rights of existing shareholders, curtail or cease
operations or, in extreme circumstances, file for bankruptcy protection. We have
spent, and we expect to continue to spend, substantial funds in connection with:

     o    research and development relating to our products and production
          technologies

     o    scale-up of our production capabilities

     o    extensive human clinical trials and

     o    protection of our intellectual property.

We believe we have enough cash (including interest income) to meet our currently
anticipated needs for operating expenses, working capital, equipment
acquisitions and current research projects through at least the second quarter
of 2002. We continue to evaluate strategic alliances, potential partnerships and
financing ar-



                                       5


rangements which would further strengthen our competitive position and provide
additional funding. Accordingly, we cannot assure you that:

     o    operations will generate meaningful funds

     o    additional agreements for product development funding can be reached

     o    strategic alliances can be negotiated or

     o    adequate additional financing will be available for us to finance our
          own development on acceptable terms, if at all.

Cash balances and operating cash flow are influenced primarily by the timing and
level of payments by the Company's licensees and development partners, as well
as by the Company's operating costs.

Because All Of Our Products Are Still In Development, We Have Sustained Losses
In The Past And We Expect To Sustain Losses In The Future

     We have experienced significant losses and, as of September 30, 2000, we
had an accumulated deficit of approximately U.S.$470.2 million.

     For the year ended December 31, 1999 and the nine months ended September
30, 2000, we had net losses of approximately U.S.$45.8 million, or U.S.$.87 per
common share (basic and diluted), and U.S.$20.0 million, or U.S.$0.31 per common
share (basic and diluted), respectively. We expect to incur additional losses in
the future. Our ability to make profits is dependent in large part on obtaining
regulatory approval for our products and entering into agreements for product
development and commercialization. Our ability to fund our ongoing operations is
dependent on the foregoing factors and on our ability to secure additional
funds. We cannot assure you that we will ever make a profit or that cash flow
from future operations will be sufficient to meet our needs.

If Third Party Collaborators Do Not Successfully Develop and Market Our
Products, We May Not Be Able To Do So On Our Own

     Our financial resources and our marketing experience and expertise are
limited. Consequently, we depend to a large extent upon securing the financial
resources and marketing capabilities of third parties with whom we collaborate.
In April 1996, XOMA and Genentech entered into an agreement whereby XOMA agreed
to co-develop Genentech's humanized monoclonal antibody product anti-CD11a. In
April 1999, the companies extended and expanded the agreement. In January 2000,
we licensed the worldwide rights to all pharmaceutical compositions containing
BPI (including NEUPREX(R)) for treatment of meningococcemia and substantially
all future anti-bacterial and anti-endotoxin human clinical indications to
Baxter Healthcare Corporation. We cannot assure you that Genentech or Baxter
will successfully develop or market any products.

     Even when we have a collaboration relationship, we cannot assure you that
it will result in successful development of marketable products. For example, in
June 1999, we licensed certain genetically-engineered fragments of BPI to
Allergan Inc. to use in combination with other anti-infectives in products to
treat bacterial ophthalmic infections. In May 2000, following successful product
testing at Allergan, we expanded the collaboration to include "stand-alone"
formulations of BPI and to cover eye infections caused by any microbes. In
November 2000, Allergan advised us that for internal economic reasons they
planned to discontinue development of BPI-derived ophthalmic anti-infective
products. We cannot assure you that we will succeed in finding another licensee
for these products or that any such licensee will be successful in developing
and marketing the products.



                                       6


     As of the date of this prospectus, we have not entered into any other
license agreements regarding our other products currently in development.
Although we continue to evaluate additional strategic alliances and potential
partnerships, we cannot predict whether or when any such alliances or
partnerships will be entered into.

If Any Of Our Products Receives Regulatory Approval, We May Not Be Able To
Increase Existing Or Acquire New Manufacturing Capacity Sufficient To Meet
Market Demand

     We have never commercially introduced any pharmaceutical products. We
cannot assure you that the capacity of our existing manufacturing facilities can
be increased to produce sufficient quantities of our products to meet market
demand. Also, if we need additional manufacturing facilities to meet market
demand, we cannot assure you that we will successfully obtain those facilities.

If Our Patent Protection For Our Principal Products Is Not Enforceable, We
Will Not Realize Our Profit Potential

     Because of the length of time and the expense associated with bringing new
products to the marketplace, we hold and are in the process of applying for a
number of patents in the United States and abroad to protect our products and
important processes and also have obtained or have the right to obtain exclusive
licenses to certain patents and applications filed by others. However, the
patent position of biotechnology companies generally is highly uncertain, and no
consistent policy regarding the breadth of allowed claims has emerged from the
actions of the U.S. Patent and Trademark Office with respect to biotechnology
patents. Legal considerations surrounding the validity of biotechnology patents
continue to be in transition, and we cannot assure you that historical legal
standards surrounding questions of validity will continue to be applied or that
current defenses as to issued biotechnology patents will in fact be considered
substantial in the future. Accordingly, we cannot assure you as to:

     o    the degree and range of protection any patents will afford against
          competitors with similar technologies

     o    if and when patents will issue

     o    whether or not others will obtain patents claiming aspects similar to
          those covered by our patent applications or

     o    the extent to which we will be successful in avoiding any patents
          granted to others.

     The Patent Office has issued and/or allowed 53 patents to us related to our
BPI-based products, including novel compositions, their manufacture,
formulation, assay and use. In addition, we are the exclusive licensee of
BPI-related patents and applications owned by New York University and Incyte
Pharmaceuticals Inc. The Patent Office has also issued and/or allowed nine
patents to us related to our bacterial expression technology.

     If certain patents issued to others are upheld or if certain patent
applications filed by others issue and are upheld, we may require licenses from
others in order to develop and commercialize certain potential products
incorporating our technology. We cannot assure you that these licenses, if
required, will be available on acceptable terms.

     Due to the uncertainties regarding biotechnology patents, we also have
relied and will continue to rely upon trade secrets, know-how and continuing
technological advancement to develop and maintain our com-



                                       7


petitive position. All of our employees have signed confidentiality agreements
under which they have agreed not to use or disclose any of our proprietary
information. Research and development contracts and relationships between us and
our scientific consultants and potential customers provide access to aspects of
our know-how that are protected generally under confidentiality agreements. We
cannot assure you that all confidentiality agreements will be honored or are
enforceable.

Other Companies May Render Some Or All Of Our Products Noncompetitive Or
Obsolete

     We cannot assure you that developments by others will not render our
products or technologies obsolete or uncompetitive. Technologies developed and
utilized by the biotechnology and pharmaceutical industries are continuously and
substantially changing. Competition in the areas of genetically-engineered
DNA-based and antibody-based technologies is intense and expected to increase in
the future as a number of established biotechnology firms and large chemical and
pharmaceutical companies advance in these fields. Many of these competitors may
be able to develop products and processes competitive with or superior to our
own for many reasons, including that they may have:

     o    significantly greater financial resources

     o    larger research and development and marketing staffs

     o    larger production facilities

     o    entered into arrangements with, or acquired, biotechnology companies
          to enhance their capabilities or

     o    extensive experience in preclinical testing and human clinical trials.

     Without limiting the foregoing, XOMA is aware that Biogen Inc. is in Phase
III testing of its Amevive(TM) product in chronic plaque psoriasis, Immunex
Corp. may be testing its rheumatoid arthritis drug in psoriasis and other
companies are developing monoclonal antibody or other products for treatment of
inflammatory skin disorders.

     These factors may enable others to develop products and processes
competitive with or superior to our own. In addition, a significant amount of
research in biotechnology is being carried out in universities and other
non-profit research organizations. These entities are becoming increasingly
interested in the commercial value of their work and may become more aggressive
in seeking patent protection and licensing arrangements.

     It is possible that one or more other companies may be developing one or
more products based on BPI, and we cannot assure you that these product(s) will
not prove to be more effective than NEUPREX(R).

If We Do Business Internationally, We Will Be Subject To Additional Political,
Economic and Regulatory Uncertainties

     We cannot assure you that we will be able to successfully operate in any
foreign market. We believe that, because the pharmaceutical industry is global
in nature, international activities will be a significant part of our future
business activities and that, when and if we are able to generate income, a
substantial portion of that income will be derived from product sales and other
activities outside the United States. Foreign regulatory agencies often
establish standards different from those in the United States, and an inability
to obtain foreign regulatory approvals on a timely basis could have an adverse
effect on our business. International operations may be limited or disrupted by:



                                       8


     o    imposition of government controls

     o    export license requirements

     o    political or economic instability

     o    trade restrictions

     o    changes in tariffs

     o    restrictions on repatriating profits

     o    taxation and

     o    difficulties in staffing and managing international operations.

     Also, our business may be adversely affected by fluctuations in currency
exchange rates.

Because We Are A Relatively Small Biopharmaceutical Company With Limited
Resources, We May Not Be Able To Attract And Retain Qualified Personnel, And
The Loss Of Key Personnel Could Delay Or Prevent Achieving Our Objectives

     Our success in developing marketable products and achieving a competitive
position will depend, in part, on our ability to attract and retain qualified
scientific and management personnel, particularly in areas requiring specific
technical, scientific or medical expertise. There is intense competition for
such personnel, and we cannot assure you that we will be able to attract or
retain them. Our research, product development and business efforts would be
adversely affected by the loss of a significant group of key members of our
scientific or management staff.

Because We Engage In Human Testing, We Are Exposed To An Increased Risk Of
Product Liability Claims, Which Would Have An Adverse Effect On Our Business

     The testing and marketing of medical products entails an inherent risk of
allegations of product liability. We believe that we currently have adequate
levels of insurance for our clinical trials. We will seek to obtain additional
insurance, if needed, if and when our products are commercialized; however, we
cannot assure you that adequate insurance coverage will be available or be
available at acceptable costs or that a product liability claim would not
materially adversely affect our business.

Our Shareholder Rights Agreement Or Bye-laws May Prevent Transactions That
Could Be Beneficial To Our Shareholders

     Our shareholder rights agreement could make it considerably more difficult
or costly for a person or group to acquire control of XOMA in a transaction that
our board of directors opposes.

     Our bye-laws:

     o    require certain procedures to be followed and time periods to be met
          for any shareholder to propose matters to be considered at annual
          meetings of shareholders, including nominating directors for election
          at those meetings;



                                       9


     o    authorize our board of directors to issue up to 1,000,000 preference
          shares without shareholder approval and to set the rights, preferences
          and other designations, including voting rights, of those shares as
          the board of directors may determine; and

     o    contain provisions, similar to those contained in the Delaware General
          Corporation Law, that may make business combinations with interested
          shareholders more difficult.

     These provisions, alone or in combination with each other, may discourage
transactions involving actual or potential changes of control, including
transactions that otherwise could involve payment of a premium over prevailing
market prices to holders of common shares, or could limit the ability of
shareholders to approve transactions that they may deem to be in their best
interests.

Because We Have No History Of Profitability And Because The Biotechnology
Sector Has Been Characterized By Highly Volatile Stock Prices, Announcements
We Make And General Market Conditions For Biotechnology Stocks Could Result In
A Sudden Change In The Value Of Our Stock

     As a biopharmaceutical company, we have experienced significant volatility
in our common shares. Fluctuations in our operating results and general market
conditions for biotechnology stocks could have a significant impact on the
volatility of our common share price. From November 1, 1999 through October 31,
2000, our share price has ranged from a low of U.S.$2 1/2 to a high of U.S.$16.
Factors contributing to such volatility include:

     o    results of preclinical studies and clinical trials,

     o    evidence of the safety or efficacy of our products,

     o    announcements of new collaborations,

     o    failure to enter into collaborations,

     o    developments in existing collaborations,

     o    our funding requirements and the terms of our financing arrangements,

     o    announcements of technological innovations or new indications for our
          therapeutic products,

     o    government regulations,

     o    developments in patent or other proprietary rights,

     o    announcements regarding other participants in the biotechnology and
          pharmaceutical industries, and

     o    market speculation regarding any of the foregoing.



                                       10


If You Were To Obtain A Judgment Against Us, It May Be Difficult To Enforce
Against Us Because We Are A Foreign Entity

     We are a Bermuda company. All or a substantial portion of our assets may be
located outside the United States. As a result, it may be difficult for
investors to enforce in United States courts judgments obtained against us. We
have irrevocably agreed that we may be served with process with respect to
actions based on offers and sales of securities made hereby in the United States
by serving Christopher J. Margolin, c/o XOMA Ltd., 2910 Seventh Street,
Berkeley, California 94710, our United States agent appointed for that purpose.
XOMA has been advised by its Bermuda counsel, Conyers Dill & Pearman, that there
is doubt as to whether Bermuda courts would enforce judgments of United States
courts obtained in (a) actions against such persons or XOMA that are predicated
upon the civil liability provisions of the Securities Act or (b) original
actions brought in Bermuda against XOMA or such persons predicated upon the
Securities Act. There is no treaty in effect between the United States and
Bermuda providing for such enforcement, and there are grounds upon which Bermuda
courts may not enforce judgments of United States courts. Certain remedies
available under the United States federal securities laws may not be allowed in
Bermuda courts as contrary to that nation's policy.




                                       11



                INCORPORATION OF INFORMATION WE FILE WITH THE SEC

     The following documents filed by XOMA with the SEC pursuant to the
Securities Exchange Act are "incorporated by reference" in this prospectus,
which means we can disclose important information to you by referring you to
these documents and they are considered to be a part of this prospectus:

(1)  annual report on Form 10-K for the fiscal year ended December 31, 1999 as
     amended by an amendment on Form 10-K/A dated and filed on April 25, 2000
     (file no. 0-14710);

(2)  quarterly reports on Form 10-Q for the quarterly periods ended March 31,
     2000, June 30, 2000 and September 30, 2000 (file no. 0-14710);

(3)  current report on Form 8-K dated January 24, 2000 filed on January 25,
     2000, as amended by amendments on Form 8-K/A dated and filed on February 3,
     2000 and March 9, 2000 (file no. 0-14710);

(4)  current report on Form 8-K dated February 11, 2000 filed on February 14,
     2000 (file no. 0-14710);

(5)  current report on Form 8-K dated and filed on April 25, 2000 (file no.
     0-14710);

(6)  amendment to current report on Form 8-K/A dated and filed on November 17,
     2000 (file no. 0-14710); and

(7)  the description of the common shares in the registration statement on Form
     8-A dated and filed on May 21, 1999 under Section 12 of the Securities
     Exchange Act, including any amendment or report for the purpose of updating
     such description (registration no. 333-68045).

     All documents filed by XOMA with the SEC pursuant to Section 13(a), 13(c),
14 or 15(d) of the Securities Exchange Act after the date of this prospectus and
before all of the common shares offered by this prospectus have been sold are
deemed to be incorporated by reference in, and to be part of, this prospectus
from the date any such document is filed.

     Any statements contained in a document incorporated by reference in this
prospectus are deemed to be modified or superseded for purposes of this
prospectus to the extent that a statement contained in this prospectus (or in
any other subsequently filed document which also is incorporated by reference in
this prospectus) modifies or supersedes such statement. Any statement so
modified or superseded is not deemed to constitute a part of this prospectus
except as so modified or superseded.




                                       12



                SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

     Some of the statements made in this prospectus are forward-looking in
nature, including those relating to the sufficiency of our cash position, the
FDA regulatory process, timing and results of clinical trials and other aspects
of product development, strategic collaborative relationships and other
statements that are not historical facts. The occurrence of the events
described, and the achievement of the intended results, depend on many events,
some or all of which are not predictable or not within our control. Actual
results may differ materially from those anticipated in any forward-looking
statements. Many risks and uncertainties are inherent in the biopharmaceutical
industry. Others are more specific to our business. Many of the significant
risks related to our business are described in this prospectus. These include,
among others, risks associated with technology and product development,
sufficiency and availability of funds, marketing risks, patent and intellectual
property matters, regulatory and manufacturing issues and risks associated with
competition from other companies. Many of these risks are discussed further in
"Risk Factors."

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

     We have not authorized any dealer, salesperson or other person to give you
written information other than this prospectus or to make representations as to
matters not stated in this prospectus. You must not rely on unauthorized
information. This prospectus is not an offer to sell these common shares or our
solicitation of your offer to buy the common shares in any jurisdiction where
that would not be permitted or legal. Neither the delivery of this prospectus
nor any sales made hereunder after the date of this prospectus should imply that
the information contained in this prospectus or the affairs of XOMA have not
changed since the date of this prospectus.




                                       13



                                      XOMA

     We are a biopharmaceutical company developing products to treat bacterial
and fungal infections, infectious complications (such as those that may follow
surgery), and immunologic and inflammatory disorders. Our current product
development programs include:

     o    Anti-CD11a, a humanized monoclonal antibody product being developed in
          collaboration with Genentech, Inc. Genentech has completed enrollment
          in two Phase III trials of anti-CD11a in psoriasis and we have
          initiated and completed enrollment in a Phase I/II study of anti-CD11a
          in kidney transplant recipients.

     o    ING-1, a high-affinity antibody to an antigen expressed on epithelial
          cell cancers (breast, colorectal, prostate and others) that destroys
          cancer cells by recruiting the patient's own immune system. We have
          initiated a Phase I study of ING-1 in cancer patients.

     o    Genimune(TM), a product developed using our proprietary targeted
          gelonin fusion technology. The product delivers a proprietary,
          genetically-engineered cytotoxin called rGelonin specifically to
          CD5-positive cells. The CD5 antigen is expressed on mature T cells and
          some B cells, but not stem cells or other tissues. The product may
          treat cancers such as T and B-cell lymphomas and chronic lymphocytic
          leukemia, as well as autoimmune diseases such as rheumatoid arthritis.
          We are seeking one or more partners for commercialization of the
          product and plan to outlicense the technology.

     o    NEUPREX(R) (rBPI21), a genetically-engineered modified fragment of a
          human protein known as BPI and our lead BPI-derived product. The
          product completed a Phase III efficacy clinical trial in 1999 in one
          indication, with the resulting clinical data published in a
          peer-reviewed medical journal in September 2000, and has been in
          various earlier phase clinical trials in four additional indications.
          Further development of this product will continue under a licensing
          agreement with Baxter Healthcare Corporation.

     o    Mycoprex(TM), a fungicidal compound that is currently in preclinical
          product development. It is initially targeted at systemic fungal
          infections. We are seeking one or more partners for commercialization
          of this product.

     o    Antiangiogenic compounds, which are in preclinical development with an
          initial focus on retinal disorders. We are seeking one or more
          partners for clinical development and commercialization of this
          product.

     We believe our cash position and resulting interest income are sufficient
to finance our currently anticipated needs for operating expenses, working
capital, equipment acquisitions and current research projects through at least
the second quarter of 2002. We continue to evaluate strategic alliances,
potential partnerships and financing arrangements which would further strengthen
our competitive position and provide additional funding. We cannot predict
whether or when any such alliances, partnerships or arrangements will be
consummated or whether additional funding will be available when required and on
terms acceptable to us.




                                       14



              PRICE RANGE OF COMMON SHARES AND DIVIDEND INFORMATION

     XOMA's common shares (such common shares and the common stock of our
predecessor Delaware corporation are referred to in this prospectus as the
common shares) trade on the Nasdaq National Market under the symbol "XOMA." The
following table sets forth the quarterly range of high and low reported sale
prices of the common shares on the Nasdaq National Market for the periods
indicated (in United States dollars):

                                                    High            Low
                                                    ----            ---

    1998:
                 First Quarter                    $6 1/2          $4 5/16
                 Second Quarter                        6            4 1/4
                 Third Quarter                         5          1 27/32
                 Fourth Quarter                        5          1 13/16

    1999:
                 First Quarter                   $4 3/16         $2 13/16
                 Second Quarter                    6 3/4            2 1/2
                 Third Quarter                         8           2 1/32
                 Fourth Quarter                    3 3/4                2

    2000:
                 First Quarter                       $16           $2 3/4
                 Second Quarter                   10 1/8            3 1/8
                 Third Quarter                    14 3/4                4
                 Fourth Quarter (through          15 1/4            7 3/4
                 November 15)


     On October 31, 2000 the last reported sale price of the common shares as
reported on the Nasdaq National Market was U.S.$12 3/16 per share. As of October
31, 2000, there were approximately 3,565 record holders of XOMA's common shares.

     XOMA has not paid dividends on its common equity. XOMA currently does not
intend to pay dividends and intends to retain any earnings for use in its
business and the financing of its capital requirements for the foreseeable
future. The payment of any future cash dividends on XOMA's common shares will
necessarily be dependent upon the earnings and financial needs of XOMA, along
with applicable legal and contractual restrictions.




                                       15



                                 USE OF PROCEEDS

     We intend to use the net proceeds from this offering for general corporate
purposes, including current research and development projects, the development
of new products or technologies, equipment acquisitions, general working capital
and operating expenses.

     We have not determined the amounts we plan to spend on any of the areas
listed above or the timing of these expenditures. As a result, our management
will have broad discretion to allocate the net proceeds from this offering.
Pending application of the net proceeds as described above, we intend to invest
the net proceeds of the offering in short-term, investment-grade,
interest-bearing securities.




                                       16



                          DESCRIPTION OF SHARE CAPITAL

     The following statements with respect to our share capital are subject to
the detailed provisions of XOMA's memorandum of continuance and bye-laws. These
statements do not purport to be complete and, while we believe the descriptions
of the material provisions of the memorandum of continuance and the bye-laws
incorporated by reference are accurate statements with respect to such material
provisions, such statements are subject to the detailed provisions in the
memorandum of continuance and the bye-laws, to which reference is hereby made
for a full description of such provisions.

COMMON SHARES

General

     The memorandum of continuance and the bye-laws provide that our authorized
common share capital is limited to 135,000,000 common shares, par value U.S.
$.0005 per share. As of October 31, 2000, there were 66,017,172 common shares
outstanding.

Voting

     The holders of common shares are entitled to one vote per share. All
actions submitted to a vote of shareholders shall be voted on by the holders of
common shares, voting together as a single class (together with the Series A
preference shares (as described below), if any), except as provided by law.

Dividends

     Holders of common shares are entitled to participate, on a share for share
basis, with the holders of any other common shares outstanding, with respect to
any dividends declared by our board of directors, subject to the rights of
holders of preference shares. Dividends will generally be payable in U.S.
dollars. We have not paid cash dividends on the common shares. We currently do
not intend to pay dividends and intend to retain any of our earnings for use in
our business and the financing of our capital requirements for the foreseeable
future. The payment of any future cash dividends on the common shares is
necessarily dependent upon our earnings and financial needs, along with
applicable legal and contractual restrictions.

Liquidation

     On a liquidation of XOMA, holders of common shares will be entitled to
receive any assets remaining after the payment of our debts and the expenses of
the liquidation, subject to such special rights as may be attached to any other
class of shares.

Redemption

     The common shares are not subject to redemption either by us or the holder
thereof.

Variation Of Rights

     Under our bye-laws, if at any time our share capital is divided into
different classes of shares, the rights attached to any class (unless otherwise
provided by the terms of the issue of the shares of that class) may be varied
with the consent in writing of the holders of a majority of the issued shares of
that class either in writing or with the sanction of a resolution passed at a
separate general meeting.



                                       17


PREFERENCE SHARES

General

     Under our memorandum of continuance and bye-laws, we have the authority to
issue 1,000,000 preference shares, par value U.S. $.05 per share. Of these,
650,000 preference shares have been designated Series A Cumulative Preference
Shares and 7,500 preference shares have been designated Convertible Preference
Shares, Series B. Under our bye-laws, subject to the special rights attaching to
any class of our shares not being varied and to any resolution approved by the
holders of 75% of the issued shares entitled to vote in respect thereof, our
board of directors may establish one or more classes or series of preference
shares having the number of shares, designations, relative voting rights,
dividend rates, liquidation and other rights, preferences and limitations that
the board of directors fixes without any shareholder approval.

The Series A Preference Shares

     There are no Series A preference shares outstanding. Pursuant to the rights
of the Series A preference shares, subject to the rights of holders of any
shares of any series of preference shares ranking prior and superior, the
holders of Series A preference shares are entitled to receive, when, as and if
declared by our board of directors out of funds legally available for the
purpose, quarterly dividends payable in cash on the first day of March, June,
September and December in each year, commencing on the first dividend payment
date after the first issuance of a share or fraction of a share of Series A
preference shares, in an amount per share equal to the greater of (a) $1.00 or
(b) 100 times the aggregate per share amount of all cash dividends, plus 100
times the aggregate per share amount of all non-cash dividends or other
distributions, other than a dividend payable in common shares, declared on the
common shares since the immediately preceding dividend payment date, or, with
respect to the first dividend payment date, since the first issuance of Series A
preference shares.

     In addition to any other voting rights required by law, holders of Series A
preference shares shall have the right to vote on all matters submitted to a
vote of our shareholders with each share of Series A preference shares entitled
to 100 votes. Except as otherwise provided by law, holders of Series A
preference shares and holders of common shares shall vote together as one class
on all matters submitted to a vote of our shareholders.

     Unless otherwise provided in the rights attaching to a subsequently
designated series of our preference shares, the Series A preference shares shall
rank junior to any other series of preference shares as to the payment of
dividends and distribution of assets on liquidation, dissolution or winding-up
and shall rank senior to the common shares. Upon any liquidation, dissolution or
winding-up of XOMA, no distributions shall be made to holders of shares ranking
junior to the Series A preference shares unless, prior thereto, the holders of
Series A preference shares shall have received an amount equal to accrued and
unpaid dividends and distributions, whether or not declared, to the date of such
payment, plus an amount equal to the greater of (1) $100.00 per share or (2) an
aggregate amount per share equal to 100 times the aggregate amount to be
distributed per share to holders of common shares or to the holders of shares
ranking on parity with the Series A preference shares, except distributions made
ratably on the Series A preference shares and all other such parity shares in
proportion to the total amount to which the holders of all such shares are
entitled upon such liquidation, dissolution or winding-up.

     If we shall enter into any consolidation, amalgamation, merger, combination
or other transaction in which common shares are exchanged for or changed into
cash, other securities and/or any other property, then any Series A preference
shares outstanding shall at the same time be similarly exchanged or changed in
an amount per share equal to 100 times the aggregate amount of cash, securities
and/or other property, as the case may be, into which or for which each common
share is changed or exchanged.



                                       18


     The Series A preference shares shall not be redeemable.

The Series B Preference Shares

     There are no Series B preference shares outstanding. The 7,500 Series B
preference shares have been designated for issuance upon conversion of the
convertible subordinated loans to us made and to be made by Genentech in
connection with the funding of the our development costs for hull24. Such loans
are and will be convertible into Series B preference shares upon the occurrence
of certain events relating to certain regulatory approvals, payment defaults,
prepayments and other circumstances. Pursuant to the rights of the Series B
preference shares, the holders of Series B preference shares will not be
entitled to receive any dividends on the Series B preference shares.

     The Series B preference shares will rank senior with respect to rights on
liquidation, winding-up and dissolution of XOMA to all classes of common shares.
Upon any voluntary or involuntary liquidation, dissolution or winding-up of
XOMA, holders of Series B preference shares will be entitled to receive $10,000
per share of Series B preference shares before any distribution is made on the
common shares. The holders of Series B preference shares will have no voting
rights, except as required under Bermuda law.

     The holders of Series B preference shares will have the right to convert
Series B preference shares into common shares at a conversion price equal to the
current market price of the common shares (determined as provided below). The
current market price will be determined (a) for Series B preference shares
issued in connection with a conversion of one or more of the convertible
subordinated loans upon certain regulatory approvals, payment defaults or in
certain other circumstances, as of the first date on which such a conversion
occurs, and (b) for Series B preference shares issued in connection with certain
prepayments of one or more of the convertible subordinated loans or a conversion
thereof in certain other circumstances, as of the date of the issuance of such
Series B preference shares.

     The Series B preference shares will be automatically converted into common
shares at its then effective conversion rate immediately upon the transfer by
the initial holder to any third party which is not an affiliate of such holder.

     We will have the right, at any time and from time to time, to redeem any or
all Series B preference shares for cash in an amount equal to the conversion
price multiplied by the number of common shares into which each such share of
Series B preference shares would then be convertible.

OUTSTANDING WARRANTS

     XOMA issued 618,681 common stock purchase warrants in June 1998. Each June
1998 warrant outstanding entitles the holder thereof to purchase one common
share, subject to anti-dilution adjustments. A holder may exercise the 1998
warrants at an exercise price of U.S.$7.00 per share on or before June 26, 2001.

     XOMA issued 250,000 common stock purchase warrants to Incyte in July 1998.
Each Incyte warrant outstanding entitles the holder thereof to purchase one
common share, subject to anti-dilution adjustments. A holder may exercise the
Incyte warrants at an exercise price of U.S.$6.00 per share on or before July 9,
2008 or earlier upon the related license becoming fully paid up.

     XOMA issued 379,000 warrants to purchase common shares in January 1999 and
March 1999, of which 175,000 remain outstanding. Each January and March 1999
warrant entitles the holder thereof to purchase one common share, subject to
anti-dilution adjustments. A holder may exercise the January and March 1999
warrants at an exercise price of U.S.$5.85008 per share on or before January 29,
2004.



                                       19


     XOMA issued 150,000 warrants to purchase common shares in July 1999. Each
July 1999 warrant entitles the holder thereof to purchase one common share,
subject to anti-dilution adjustments. A holder may exercise the July 1999
warrants at an exercise price of U.S.$5.75 per share on or before July 21, 2004.

     XOMA issued 250,000 warrants to purchase common shares in February 2000.
Each February 2000 warrant entitles the holder thereof to purchase one common
share, subject to anti-dilution adjustments. A holder may exercise the 2000
warrants at an exercise price of U.S.$5.00 per share on or before February 11,
2005.

     None of the warrants described above have been registered under the
Securities Act and none may be transferred except pursuant to an effective
registration statement under the Securities Act or pursuant to an exception from
registration thereunder. Additionally, all of the warrants contain certain
restrictions on their transfer. XOMA is not obligated and does not intend to
register the warrants under the Securities Act.



                                       20



                              PLAN OF DISTRIBUTION

     We may sell the common shares being offered hereby in one or more of the
following ways from time to time:

     o    through dealers or agents to the public or to investors;

     o    to underwriters for resale to the public or to investors;

     o    directly to investors (including upon conversion, exchange or exercise
          of outstanding securities of XOMA); or

     o    through a combination of such methods.

     We will set forth in a prospectus supplement the terms of the offering of
securities, including:

     o    the name or names of any agents, dealers or underwriters;

     o    the purchase price of the securities being offered and the proceeds we
          will receive from the sale;

     o    any over-allotment options under which underwriters may purchase
          additional securities from us;

     o    any agency fees or underwriting discounts and other items constituting
          agents' or underwriters' compensation;

     o    any discounts or concessions allowed or reallowed or paid to dealers;
          and

     o    any securities exchanges on which such securities may be listed.

                                  LEGAL OPINION

     The validity of the common shares to which this prospectus relates has been
passed upon for XOMA by Conyers Dill & Pearman, located in Hamilton, Bermuda.

                                     EXPERTS

     The consolidated financial statements of XOMA Ltd. at December 31, 1998 and
1999 and for the years then ended, appearing in XOMA Ltd.'s annual report (Form
10-K), as amended, for the year ended December 31, 1999 have been audited by
Ernst & Young LLP, independent auditors, as set forth in their report thereon
included therein and incorporated herein by reference. Such consolidated
financial statements are incorporated herein by reference in reliance upon such
report given on the authority of such firm as experts in accounting and
auditing.

     The financial statements of XOMA Ltd. for the periods through December 31,
1997 incorporated by reference in this prospectus and elsewhere in the
registration statement, to the extent and for the periods indicated in their
report, have been audited by Arthur Andersen LLP, independent public
accountants, as indicated in their report with respect thereto, and are
incorporated by reference herein in reliance upon the authority of said firm as
experts in giving said report.



                                       21


                       WHERE YOU CAN GET MORE INFORMATION

     This prospectus is part of a registration statement that we have filed with
the SEC. The registration statement contains exhibits and other information not
included in this prospectus. At your request, we will provide you, without
charge, a copy of any documents incorporated by reference in, or included as
exhibits to, our registration statement. If you would like more information,
write or call us at:

                                    XOMA Ltd.
                               2910 Seventh Street
                               Berkeley, CA 94710
                            Telephone: (510) 644-1170

     XOMA files annual, quarterly and current reports, proxy statements and
other information with the SEC. You may read and copy any reports, statements
and other information we file at the SEC's public reference room at 450 Fifth
Street, N.W., Washington D.C. 20549. You can request copies of these documents,
upon payment of a duplicating fee, by writing to the SEC. Please call the SEC at
1-800-SEC-0330 for further information on the operation of the public reference
rooms. XOMA's SEC filings are also available to the public on the SEC Internet
site at http://www.sec.gov.





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