<PAGE>

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                    FORM 10-K

/X/      ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
         EXCHANGE ACT OF 1934

For the fiscal year ended  January 31, 2000
                          -----------------

                         Commission file number: 1-8366
                                                -------

                         POLYDEX PHARMACEUTICALS LIMITED
             (Exact Name of Registrant as Specified in Its Charter)

    Commonwealth of the Bahamas                                     None
  -------------------------------                            ------------------
  (State or Other Jurisdiction of                             (I.R.S. Employer
  Incorporation or Organization)                             Identification No.)

  421 Comstock Road, Toronto, Ontario, Canada                      M1L 2H5
  -------------------------------------------                    ----------
  (Address of Principal Executive Offices)                       (Zip Code)

Registrant's telephone number, including area code  (416) 755-2231
                                                   ---------------

Securities registered pursuant to Section 12(b) of the Act:

    Title of Each Class                Name of Each Exchange on Which Registered
-------------------------------        -----------------------------------------
Common Shares, $.0167 Par Value        Boston Stock Exchange

Securities registered pursuant to Section 12(g) of the Act:  Same
                                                             ----

Indicate by check mark whether the Registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes  X   No
                                             -----   -----

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. /X/

The aggregate market value of the Registrant's voting stock held by
non-affiliates of the Registrant, computed by reference to the average bid and
ask prices of such stock as of March 31, 2000: $21,771,506.25.

The number of Common Shares outstanding as of March 31, 2000:  3,024,418.

                       Documents Incorporated By Reference

Portions of the Registrant's Annual Report to Shareholders for the fiscal
year ended January 31, 2000, are incorporated by reference into Part II.

Portions of the Registrant's definitive Proxy Statement for the Annual
Meeting of Shareholders to be held on June 23, 2000, are incorporated by
reference into Part III.

<PAGE>

                                     PART I

ITEM 1.           BUSINESS

INTRODUCTION

         Polydex Pharmaceuticals Limited (the "Registrant") was incorporated
under the laws of the Commonwealth of the Bahamas on June 14, 1979 as Polydex
Chemicals Limited, and changed its name on March 28, 1984. The address of its
statutory office in the Bahamas is c/o Higgs & Johnson, 83 Shirley Street,
Nassau, Bahamas: telephone (242) 322-8571. The Registrant's current business
is conducted through two of its subsidiaries, Polydex Chemicals (Canada)
Limited, a wholly-owned Canadian corporation incorporated in 1969, which
itself conducts its business through its wholly-owned subsidiary, Dextran
Products Limited ("Dextran Products") (incorporated in Ontario in 1966) and
Chemdex, Inc. ("Chemdex"), a 90% owned Kansas corporation incorporated in
1987. On November 30, 1992, Chemdex acquired from Continental Grain Company
100% of the issued and outstanding share capital of Veterinary Laboratories
Inc. ("Vet Labs"), a Kansas corporation, which previously had been
wholly-owned by the Registrant. On December 1, 1992, Vet Labs and Sparhawk
Laboratories Inc. ("Sparhawk") entered into a joint venture (the "Sparhawk
Joint Venture") for the purpose of manufacturing and selling veterinary
pharmaceutical products. Sparhawk is an affiliated company owned primarily by
the management of the Sparhawk Joint Venture. The Registrant controls the
Sparhawk Joint Venture through its control of the board of directors. On May
9, 1995, the Registrant acquired from its then Chairman (now Vice-Chairman),
Thomas C. Usher, a 90% interest in Novadex International Inc. ("Novadex
International"), a Bahamian corporation. The Registrant acquired the
remaining 10% interest in Novadex International from an unaffiliated third
person on July 14, 1997. The principal asset of Novadex International is a
patent, developed by Mr. Usher, for the use of Cellulose Sulphate in a number
of applications including the development of a new contraceptive gel.

GENERAL

         The current business of the Registrant is the manufacture and sale
of Dextran and several of its derivatives, including Iron Dextran and Dextran
Sulphate, veterinary pharmaceutical products and other specialty chemicals,
and cosmetic raw materials, with some related research and development. The
Registrant is investigating the potential human applications of some of its
products although it is impossible to determine at this time if the products
will reach market.

         Dextran, a generic name applied to certain synthetic compounds
formed by bacterial growth on sucrose, is a polymer or giant molecule. The
name Polydex combines the words "polymer" and "dextran."


                                        -2-

<PAGE>

DESCRIPTION, USAGE AND REGULATED ASPECTS OF THE PRODUCTS

         The operations of the Registrant are presently carried on through
Dextran Products and Vet Labs. These subsidiaries operate in two industry
segments: the manufacture and sale of Dextran and derivatives and the
manufacture and sale of veterinary pharmaceutical products

IRON DEXTRAN

A.  DESCRIPTION

         Iron Dextran is a derivative of Dextran produced by complexing Iron
with Dextran. Iron Dextran is injected into most pigs at birth as a treatment
for anemia.

B.  REGULATION AND USAGE

         Sales presently are being made by the Registrant in the following
countries, which have approved the use of Iron Dextran for animals, require
no approval, or accept the Canadian registration: Canada (registration number
R625), Denmark, France, Switzerland, Hong Kong, Germany, the Netherlands,
Finland, Ecuador, Thailand, Hungary, Italy, Malaysia, the Philippines, Japan,
Brazil, Korea, Spain, Sweden, Israel, New Zealand, Mexico, Costa Rica, and
Australia. In the United States, sale for veterinary use requires the
approval of the U.S. Food and Drug Administration (the "FDA"). Chemdex has
FDA approval for veterinary use of Iron Dextran in the United States. For
classification purposes, the Registrant treats these sales of the Iron
Dextran raw materials as sales of Iron Dextran.

DEXTRAN SULPHATE

A.  DESCRIPTION

         Dextran Sulphate is a specialty chemical which finds use in research
applications of the pharmaceutical industry and other centers of chemical
research.

B.  REGULATION AND USAGE

         The Dextran Sulphate manufactured by the Registrant is sold in
Australia, Switzerland, France, the Netherlands, New Zealand and the United
States, where it is used in limited quantities in the manufacture of film, as
well as analytical chemical applications. This usage requires no regulatory
approval.


                                        -3-

<PAGE>

VETERINARY PRODUCTS

A.  DESCRIPTION

         The Registrant manufactures sterile injectable products, tablets and
boluses, internal and external solutions, ointments and powders.

B.  REGULATION AND USAGE

         The products are sold in the United States and are predominantly
used by large animal veterinarians and by farmers for the treatment of
various diseases and conditions that affect farm animals. The Vet Labs
facility is regulated and inspected by the FDA and the U.S. Drug Enforcement
Agency.

SALES, DISTRIBUTION AND RELIANCE UPON FOREIGN COUNTRIES

IRON DEXTRAN AND DEXTRAN SULPHATE

         The Registrant sells Iron Dextran on an exclusive basis in certain
countries and on a non-exclusive basis elsewhere. Dextran Sulphate is sold on
a non-exclusive basis throughout the world. For the fiscal year ended January
31, 2000, no single customer accounted for 10% or more of total sales.

         The Registrant has not changed its mode of distribution of Iron
Dextran or Dextran Sulphate during the past thirteen fiscal years. The
Registrant sells its product primarily to independent distributors and
wholesalers throughout the world. Orders are forwarded to the Registrant's
manufacturing facilities in Toronto, Ontario, Canada where they are processed
and shipped. The Canadian Embassies and Consulates in various countries also
assist the Registrant by making available information regarding the
Registrant and its products.

VETERINARY PRODUCTS

         All of the sales of Vet Labs for the fiscal year ended January 31,
2000 were within the United States. Distribution is achieved through private
label buying groups who then distribute to their own distributors, and
through full service independent distributors who purchase products under Vet
Labs' house labels. Private label products accounted for approximately 85% of
sales with house label sales contributing approximately 11%. In addition, Vet
Labs also does "contract filling" for other industry companies. Four
customers (all private label buying groups) accounted for 70% of sales at Vet
Labs, with individual customer shares ranging from less than 1% to 23%.
Management does not believe that the loss of any one or more of these
customers would have a material adverse effect upon Vet Labs' results of
operations.


                                        -4-

<PAGE>

WORKING CAPITAL REQUIREMENTS

         There are no special inventory requirements or credit terms extended
to customers that would have a material adverse effect upon the Registrant's
working capital.

PATENTS, TRADEMARKS AND LICENSES

IRON DEXTRAN

         Effective February 1, 1995, the Registrant entered into an agreement
with Novadex Corp., an affiliated company, whereby Novadex Corp. granted the
Registrant the exclusive worldwide license to use a certain process developed
by Novadex Corp. for producing Iron Dextran. This process allows the
Registrant to produce Iron Dextran at a lower cost than would otherwise be
possible. The term of the license agreement is 10 years. The Registrant pays
a license fee based on production volumes. Upon the expiration of the
license, the technology relating to the process described above will belong
to the Registrant, with no further obligation to make royalty payments to
Novadex Corp.

         During July 1999, Novadex Corp. was liquidated, and all assets and
liabilities of Novadex Corp. were assumed by the sole shareholder of Novadex
Corp., the Vice Chairman of the Registrant. The above-referenced license
agreement was included in the assets transferred to the Vice Chairman. As of
the effective date of the transfer, the Registrant is obligated to pay the
license fee to the Vice Chairman.

         The technology in the field of Dextran and its derivatives is
undergoing continuous expansion and development. The manufacture of Dextran
and its derivatives may be achieved by different processes and variations
(including glycoside, which is in the public domain). Therefore, the
Registrant does not believe that the license agreement described above gives
it any substantial competitive advantage.

DEXTRAN SULPHATE

         This material was patented under U.S. patent number 4,855,410 in
August, 1989 and has been tested with other drugs for efficacy in controlling
the HIV virus. At this time research has been halted so that the Registrant
can focus its resources on projects relating to cystic fibrosis and Cellulose
Sulphate. Once these projects have been completed, the Registrant expects to
return its attention to Dextran Sulphate.

VETERINARY PRODUCTS

         Vet Labs holds a New Animal Drug Application from the FDA for the
production of 10% Iron Hydrogenated Dextran for injection. In addition,
Chemdex holds a Drug Master File for the


                                        -5-

<PAGE>

manufacture of 10% Bulk Iron Hydrogenated Dextran which makes it the only
approved source of Bulk Iron in the United States.

ELASTIN AND COLLAGEN

         These materials were patented under U.S. patent numbers 4,659,740
and 4,784,986 on April 21, 1987 and November 15, 1988, respectively. The
patents cover a process whereby the materials are modified in such a way as
to penetrate the skin and act as a hydrating agent.

CELLULOSE SULPHATE

         During the fiscal year ended January 31, 1996, a patent for a new
method of manufacture of Cellulose Sulphate was purchased for $1 million. The
process was patented under U.S. patent number 5,378,828 in June of 1995.
Prior to development of the patented process the manufacture of the compound
required the use of dangerous and environmentally sensitive chemicals. The
new method is safer, and appears to produce a more consistent product. This
material appears to have applications in film manufacture and capsule
production and is presently being investigated in conjunction with the Rush
Medical Center in Chicago, Illinois as a potential contraceptive which also
has antiviral capabilities.

CYSTIC FIBROSIS

         Effective April 1, 1994, the Registrant entered into a Research
Agreement (the "UBC Research Agreement") with an affiliated company and the
University of British Columbia ("UBC"). On April 1, 1996, the UBC Research
Agreement was amended and expanded to include a number of Canadian hospitals.
Under the terms of the UBC Research Agreement, the Registrant has agreed to
provide equipment and funding in return for continuing research on cystic
fibrosis to be carried out in connection with two patents issued in 1996.
U.S. patent number 5,441,938 is held jointly by UBC and the Registrant,
whereas U.S. patent number 5,514,665 is held by UBC and licensed to the
Registrant. In conjunction with the UBC Research Agreement, UBC granted the
Registrant, through a sublicensing agreement with an affiliated company, an
exclusive worldwide license to manufacture, distribute and sell products
derived or developed from the research performed. During fiscal 2000, the
Registrant and UBC licensed the cystic fibrosis product to BCY Ventures Inc.
("BCY Ventures") of Vancouver, British Columbia, Canada. Under this license
agreement, BCY Ventures will pay a royalty to both the Registrant and UBC
based on sales and sublicensing revenue in return for the exclusive right to
sublicense, manufacture, distribute and sell the developed products.

STATUS OF NEW PRODUCTS OR INDUSTRY SEGMENTS

         There has been no public announcement of, and no information
otherwise has been made public about, a new product or industry segment that
would require the investment of a material amount of the assets of the
Registrant or that otherwise is material.


                                        -6-

<PAGE>

SUPPLIERS AND SALES

IRON DEXTRAN AND DEXTRAN SULPHATE

         With regard to its basic raw materials, the Registrant utilizes one
basic supplier for its sugar requirements and one basic supplier for its
Iron. Both of these materials, as well as others used by the Registrant, are
readily available from numerous suppliers at competitive prices in the
market. The Registrant has no long-term contracts with any of its suppliers.

         The Registrant is dependent upon a single source for a certain raw
material used in the production of Dextran Sulphate. Such supply was adequate
in fiscal 2000 and no shortages are anticipated in the near term. However,
any curtailment in availability of such raw material could be accompanied by
production or other delays as well as increased raw material costs, with
consequent adverse effect on the Registrant's results of operations.

VETERINARY PRODUCTS

         Raw materials are readily available from a variety of suppliers at
competitive prices in the market. The Registrant has no long-term contracts
with any of its suppliers.

BACKLOG AND SEASONALITY

         The Registrant's backlog as at January 31, 2000 was approximately
$1,500,000, whereas backlog as at January 31, 1999 was approximately
$800,000. All of these orders are expected to be filled within the current
fiscal year. The Registrant's business is not seasonal to any material extent.

COMPETITION

         The Registrant is the only Canadian manufacturer of Iron Dextran
and, as a result of its ownership of Vet Labs, the Registrant is also the
only manufacturer of the 10% Bulk Solution in the United States. There exist
several European sources of Iron Dextran. However, the only other major
supplier of Iron Dextran is located in Denmark. Dextran Sulphate is also
manufactured by several manufacturers in the U.S. and Europe. With regard to
Iron Dextran and Dextran Sulphate, the Registrant competes on the basis of
quality, service and price.

         The Registrant currently produces approximately 50 veterinary
products including analgesics, anti-diarrheals, topical antiseptics,
nutritional supplements, local and general anesthesia agents and euthanizing
agents. Primary market segments include beef and dairy cattle, swine, equine
and to a small extent, companion animals (dogs and cats). With the exception
of Iron Dextran and Nitrofurazone ointment, the product offering is generic
or non-licensed (non NADA). As such, all products are subject to numerous
competitors. In addition to competing on the basis of quality, service and
price, the Registrant differentiates itself from


                                        -7-

<PAGE>

competitors through its ability to supply multiple product dosage forms
(i.e., injectables, boluses, tablets, liquids and powders) and provide
customers with technical and regulatory support and assistance from in-house
quality control and regulatory departments.

RESEARCH AND DEVELOPMENT

         During the fiscal years ended January 31, 2000, 1999, and 1998, the
Registrant expended $677,111, $234,825 and $213,988, respectively, on
research and development relating primarily to the development of Cellulose
Sulphate and a raw material for a human injectable product. The fiscal 2000
increase is due to the commencement of the human injectable project. During
the years ended January 31, 2000, 1999 and 1998, the Registrant recognized
investment tax credit benefits of $39,794, $201,762 and $29,087, respectively.

ENVIRONMENTAL COMPLIANCE

         The Registrant believes that it is in substantial compliance with
all existing applicable foreign, federal, state and local environmental laws
and does not anticipate that such compliance will have a material effect on
its future capital expenditures, earnings or competitive position.

GOVERNMENTAL CONTRACTS

         No portion of the Registrant's business is subject to renegotiation
of profits or termination of contracts or subcontracts at the election of the
U.S. Government.

EMPLOYEES

         As of March 31, 2000, the Registrant employed 85 employees, of whom
56 were engaged in production, 16 in quality control, 2 in research and
development, 9 in administration and 2 in marketing and sales activities. Of
such employees, 57 were employed by Vet Labs and 28 by Dextran Products. None
of the Registrant's employees are covered by collective bargaining
agreements. Management considers its relations with employees to be good.

RECENT DEVELOPMENTS -- NEW PRODUCTS

ACTIVATED COLLAGEN AND ELASTIN

         Collodex, a modified collagen, has been formulated as a principal
ingredient of a cosmetic skin cream. During fiscal 2000, the Registrant
engaged several marketing companies for the promotion of this product. To
date, efforts by these companies have met with limited success. At the
present time, minor sales are being made to cosmetic manufacturers in the
Pacific Rim with the potential for increased sales in the future.


                                        -8-

<PAGE>

         Elastin, a material with similar applications, has been developed by
the Registrant. It has not been commercialized, however, and no sales are
expected to occur in the current fiscal year.

CYSTIC FIBROSIS

         Cystic fibrosis is a genetic disease which causes a cascade of
effects, the most severe being a build up of mucus in the lungs. This mucus
is difficult to remove and also permits the colonization of bacteria which
then cause secondary infections and often death. Research relating to cystic
fibrosis is underway in collaboration with the University of British Columbia
where in vitro studies are being performed. This research has shown that a
special form of Dextran, Usherdex 4, is effective in preventing the
colonization of bacteria in the mouth and in stimulating the macrophages in
the lungs to remove the bacteria present and lessen secondary infections.
Research into the identification of the most effective components of Usherdex
4 is scheduled to begin in the first quarter of fiscal 2001.

CELLULOSE SULPHATE

         Production of this product was halted in 1989 when the customer
found a substitute. However, interest in the industrial use of Cellulose
Sulphate has been revived and samples have been supplied, but it is difficult
to predict if sales will occur this year. As discussed above, research is
also underway in the United States to evaluate the use of this material as a
contraceptive gel with antiviral capabilities. During the most recent fiscal
year, the Registrant successfully completed a Phase I human clinical trial
with support from the Consortium for Industrial Collaboration in
Contraceptive Research ("CICCR"). Should continued positive results be
generated from this work, the Registrant has been advised that the funding
from CICCR will continue through Phase II trials. Other organizations have
also voiced interest in contributing to the development of this product. The
Registrant maintains an exclusive worldwide license for this product.

SEGMENTED INFORMATION

         The information regarding the geographic distribution of revenue,
operating results and assets set forth in Note 15 to the Registrant's
Consolidated Financial Statements included in the Registrant's Annual Report
to Shareholders for the fiscal year ended January 31, 2000 is incorporated
herein by reference.

ITEM 2.           PROPERTIES

         The Registrant's wholly-owned subsidiary, Polydex Chemicals (Canada)
Limited, maintains its executive and sales offices and its manufacturing
plant of approximately 30,000 square feet in Toronto, Ontario, Canada.


                                        -9-

<PAGE>

         The Registrant operates a fermentation plant in Toronto, Ontario,
Canada, having the capacity to produce both 10% and 20% Iron Dextran at the
rate of up to 11,000 liters a week (there are 1.057 quarts in one liter).
Present production is approximately 10,000 liters a week. Complexing of the
Iron Dextran takes place in Toronto, Ontario, Canada.

         Dextran Sulphate presently is manufactured at the Registrant's plant
in Toronto, Ontario, Canada where reactors and spray drying equipment are
available. The Registrant presently manufactures approximately 500 kilos of
Dextran Sulphate per quarter (there are 2.2 pounds in one kilo), and has the
capacity to manufacture 500 kilos per month simultaneously with the 11,000
liters per week of Iron Dextran.

         The Toronto facility has been divided into 11 discrete production
areas identified for refurbishment. In the second half of fiscal 2000 the
Registrant initiated the refurbishing program with the commissioning of a
Distillation Column at a cost of $725,000. This unit has been sized for the
ability to significantly increase the production capacity of the plant.
However, due to the interrelationships between the various production areas,
any increase in production will not be realized until the majority of the
identified production areas have been renovated. Further progress on the
refurbishment program is scheduled for fiscal 2001.

         Through its subsidiary Vet Labs, the Registrant manufactures tablets
and boluses, internal and external solutions, ointments, powders and
injectable products. The manufacturing facility is located on 8 acres of land
in Lenexa, Kansas. The plant is 55,000 square feet with separate production
areas for each of the above product groups. The plant has the capacity to
manufacture over 200,000 boluses per day, 4,000 gallons of liquids per day,
1,500 pounds of powder per day and 1,000 gallons of injectable products per
day. The facility is currently running at approximately 50% of capacity.

         Each of the properties described above is owned by the Registrant.
Management believes that the Registrant's facilities are adequate for its
present requirements. These facilities have additional capacity for expansion
of production of existing and new products. The Registrant considers its
current equipment to be in good condition and suitable for the operations
involved.

ITEM 3.           LEGAL PROCEEDINGS

         There are no material pending legal proceedings other than ordinary
routine litigation incidental to the business, to which the Registrant or any
of its subsidiaries is a party, or to which any of the their property is
subject.

ITEM 4.           SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

         No matters were submitted to a vote of security holders, through the
solicitation of proxies or otherwise, during the Registrant's fourth quarter
ended January 31, 2000.


                                       -10-

<PAGE>

                                     PART II

ITEM 5.           MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED
                  SHAREHOLDER MATTERS

         The information contained under the caption "Market for the
Company's Common Shares and Related Security Holder Matters" in the
Registrant's Annual Report to Shareholders for the fiscal year ended January
31, 2000 is incorporated herein by reference.

         The following information is provided in addition to the information
incorporated by reference as mentioned above.

         There are no governmental laws, decrees or regulations in the
Commonwealth of the Bahamas applicable to the Registrant that restrict the
export or import of capital, including foreign exchange controls, or that
affect the remittance of dividends or other payments to nonresident holders
of the Registrant's Common Shares. Furthermore, U.S. holders of the
Registrant's Common Shares are not subject to taxes under Bahamian law.

ITEM 6.           SELECTED FINANCIAL DATA

         The information required under this item is included under the
caption "Financial Highlights" in the Registrant's Annual Report to
Shareholders for the fiscal year ended January 31, 2000 and is incorporated
herein by reference.

ITEM 7.           MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                  CONDITION AND RESULTS OF OPERATIONS

         The information required under this item is included under the
caption "Management's Discussion and Analysis of Financial Condition and
Results of Operations" in the Registrant's Annual Report to Shareholders for
the fiscal year ended January 31, 2000 and is incorporated herein by
reference.


                                       -11-

<PAGE>

ITEM 7A.          QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET
                  RISK


POLYDEX PHARMACEUTICALS LIMITED AND SUBSIDIARIES
JANUARY 31, 2000
INTEREST RATE SENSITIVITY

     The table below provides information about the Company's financial
     instruments that are sensitive to changes in interest rates. All financial
     instruments are held for other than trading purposes. The Company does not
     have a material exposure to interest rate risk.

     The table presents principal cash flows and related weighted average
     interest rates by expected maturity dates.

<TABLE>
<CAPTION>

                                                       Expected Maturity Date
                           -------------------------------------------------------------------------------               Fair
                            31-Jan-01    31-Jan-02     31-Jan-03   31-Jan-04   31-Jan-05   Thereafter      Total         Value
                           ----------    ---------     ---------   ---------   ---------   ----------   ----------     ----------
<S>                        <C>           <C>           <C>         <C>         <C>         <C>          <C>            <C>
                                                                       (US$ Equivalent)
           ASSETS
Notes receivable:
   Variable rate ($US)         82,898       20,837        22,504      24,304      26,249     510,641       687,434        687,434
       Average interest
         rate                    7.87%        8.00%         8.00%       8.00%       8.00%       7.75%         7.94%

           LIABILITIES:
Long-term debt:
   Fixed rate ($US)           474,043      285,903       749,739           -           -           -     1,509,685      1,509,685
       Average interest
         rate                    9.01%        9.00%         9.00%       0.00%       0.00%       0.00%         9.00%
   Fixed rate ($CDN)          167,506      190,277        88,130      88,976      97,322     212,723       844,933        844,933
       Average interest
         rate                    9.04%        9.03%         9.23%       9.00%       9.00%       9.00%         9.05%
   Variable rate ($US)        (46,820)     (50,565)      (54,611)    (58,979)    (63,698)    947,420       672,747        672,747
       Average interest
         rate                    8.00%        8.00%         8.00%       8.00%       8.00%       8.00%         8.00%
</TABLE>

<PAGE>

POLYDEX PHARMACEUTICALS LIMITED AND SUBSIDIARIES
JANUARY 31, 2000
EXCHANGE RATE SENSITIVITY

     The table below provides information about the Company's financial
     instruments that are sensitive to changes in foreign currency exchange
     rates. All financial instruments are held for other than trading purposes.
     The Company's major exposure to exchange rate risk is that the Canadian
     dollar rises dramatically in relation to the U.S. dollar and that this
     significantly reduces the gross margin experienced at Dextran Products.
     Management monitors the margin at Dextran to ensure that an acceptable
     margin level is maintained. Management has the ability, to some extent, to
     adjust sales prices to maintain an acceptable margin level.

     The table presents principal cash flows and related weighted average
     interest rates by expected maturity dates.

<TABLE>
<CAPTION>

                                                       Expected Maturity Date
                           -------------------------------------------------------------------------------               Fair
                            31-Jan-01    31-Jan-02     31-Jan-03   31-Jan-04   31-Jan-05   Thereafter      Total         Value
                           ----------    ---------     ---------   ---------   ---------   ----------   ----------     ----------
<S>                        <C>           <C>           <C>         <C>         <C>         <C>          <C>            <C>
                                                                               (US$ Equivalent)

           LIABILITIES:
Long-term debt:
    Fixed rate ($CDN)         167,506      190,277       88,130       88,976       97,322      212,723      844,933      844,933
       Average interest
         rate                    9.04%        9.03%        9.23%        9.00%        9.00%        9.00%        9.05%
</TABLE>

<PAGE>

ITEM 8.           FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

         The Registrant's Consolidated Financial Statements are included in the
Registrant's Annual Report to Shareholders for the fiscal year ended January 31,
2000 and are incorporated herein by reference. Supplementary financial
information is not required.

ITEM 9.           CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON
                  ACCOUNTING AND FINANCIAL DISCLOSURE

         Not applicable.


                                        -13-

<PAGE>

                                    PART III

ITEM 10.          DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

         The information required under this item is incorporated herein by
reference from the material contained under the captions "Board of
Directors," "Report of the Audit Committee," "Proposals,""Executive Officers"
and "Section 16(a) Beneficial Ownership Reporting Compliance" in the
Registrant's definitive proxy statement to be filed with the Securities and
Exchange Commission pursuant to Regulation 14A, not later than 120 days after
the end of the fiscal year.

ITEM 11.          EXECUTIVE COMPENSATION

         The information required under this item is incorporated herein by
reference from the material contained under the captions "Board of
Directors," "Board Meetings and Committees," "Compensation of Executive
Officers," "Employment Agreements" and "Company Stock Performance" in the
Registrant's definitive proxy statement to be filed with the Securities and
Exchange Commission pursuant to Regulation 14A, not later than 120 days after
the end of the fiscal year.

ITEM 12.          SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND
                  MANAGEMENT

         The information required under this item is incorporated herein by
reference from the material contained under the caption "Ownership of Voting
Securities" in the Registrant's definitive proxy statement to be filed with
the Securities and Exchange Commission pursuant to Regulation 14A, not later
than 120 days after the end of the fiscal year.

ITEM 13.          CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

         The information required under this item is incorporated herein by
reference from the material contained under the caption "Transactions With
the Company" in the Registrant's definitive proxy statement to be filed with
the Securities and Exchange Commission pursuant to Regulation 14A, not later
than 120 days after the end of the fiscal year.


                                       -14-

<PAGE>

                                     PART IV

ITEM 14.          EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON
                  FORM 8-K

         (a)      The following documents are filed as a part of this Annual
                  Report on Form 10-K:

                  (1)     Financial Statements included in the Registrant's
                          Annual Report to Shareholders for the fiscal year
                          ended January 31, 2000 and incorporated by reference
                          from Exhibit 13 filed herewith.

                          Report of Independent Auditors -- Ernst & Young LLP,
                          Chartered Accountants
                          Consolidated Balance Sheets
                          Consolidated Statements of Shareholders' Equity
                          Consolidated Statements of Operations
                          Consolidated Statements of Cash Flows
                          Notes to Consolidated Financial Statements

                  (2)     Financial Statement Schedules

                          Schedules for which provision is made in the
                          applicable accounting regulation of the Securities
                          and Exchange Commission are not required under the
                          related instructions or are inapplicable, and
                          therefore, have been omitted.

                  (3)     Exhibits

                          3.1      Memorandum of Association of Polydex
                                   Pharmaceuticals Limited, as amended (filed
                                   as Exhibit 3.1 to the Annual Report on Form
                                   10-K filed April 30, 1997, and incorporated
                                   herein by reference)
                          3.2      Articles of Association of Polydex
                                   Pharmaceuticals Limited, as amended (filed
                                   as Exhibit 3.2 to the Quarterly Report on
                                   Form 10- Q filed September 13, 1999, and
                                   incorporated herein by reference)
                          10.1     Employment Agreement between Polydex
                                   Pharmaceuticals Limited and Thomas C. Usher
                                   dated December 22, 1993, as amended on
                                   November 1, 1996 (filed as Exhibit 10.1 to
                                   the Annual Report on Form 10-K filed April
                                   30, 1997, and incorporated herein by
                                   reference)*


                                       -15-

<PAGE>

                          10.2     Amendment to Employment Agreement between
                                   Polydex Pharmaceuticals Limited and Thomas
                                   C. Usher dated February 1, 1999 (filed as
                                   Exhibit 10.2 to the Annual Report on Form
                                   10-K filed April 29, 1999, and incorporated
                                   herein by reference)*
                          10.3     Employment Agreement between Polydex
                                   Pharmaceuticals Limited and George G. Usher
                                   dated December 22, 1993 (filed as Exhibit
                                   10.2 to the Annual Report on Form 10-K filed
                                   April 30, 1997, and incorporated herein by
                                   reference)*
                          10.4     Amendment to Employment Agreement between
                                   Polydex Pharmaceuticals Limited and George
                                   G. Usher dated February 1, 1999 (filed as
                                   Exhibit 10.4 to the Annual Report on Form
                                   10-K filed April 29, 1999, and incorporated
                                   herein by reference)*
                          10.5     Research Agreement among Dextran Products
                                   Limited, Canadian Microbiology Consortium,
                                   British Columbia's Children's Hospital and
                                   the University of British Columbia, dated
                                   April 1, 1996 (filed as Exhibit 10.4 to the
                                   Annual Report on Form 10-K filed April 30,
                                   1997, and incorporated herein by reference)
                          10.6     Joint Venture Agreement among Chemdex, Inc.,
                                   Veterinary Laboratories Inc. and Sparhawk
                                   Laboratories, Inc., dated December 1, 1992
                                   (filed as Exhibit 10.5 to the Annual Report
                                   on Form 10-K filed April 30, 1997, and
                                   incorporated herein by reference)
                          10.7     Manufacturing Agreement among Sparhawk
                                   Laboratories, Inc., Agri Laboratories, Ltd.
                                   and Veterinary Laboratories Inc., dated
                                   September 23, 1996 (filed as Exhibit 10.6 to
                                   the Annual Report on Form 10-K filed April
                                   30, 1997, and incorporated herein by
                                   reference)
                          10.8     Stock Sale and Purchase Agreement between
                                   Continental Grain Company and Polydex
                                   Pharmaceuticals Limited dated October 30,
                                   1992, as amended on November 22, 1996 (filed
                                   as Exhibit 10.8 to the Annual Report on Form
                                   10-K filed April 30, 1997, and incorporated
                                   herein by reference)
                          13       Annual Report to Shareholders for the fiscal
                                   year ended January 31, 2000 (only those
                                   portions incorporated herein by reference)
                          21       Subsidiaries of Polydex Pharmaceuticals
                                   Limited
                          27       Financial Data Schedule

*  Indicates a management contract or compensatory plan or arrangement


                                       -16-

<PAGE>

         (b)      Reports on Form 8-K

                  Not applicable.


                                       -17-

<PAGE>

                                   SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange
Act of 1934, the Registrant has duly caused this Annual Report on Form 10-K to
be signed on its behalf by the undersigned, thereunto duly authorized.

                                          POLYDEX PHARMACEUTICALS LIMITED

Dated April 28, 2000                      By: /s/ George G. Usher
                                             -------------------------------
                                             George G. Usher, President and
                                               Chief Executive Officer

Pursuant to the requirements of the Securities Exchange Act of 1934, this Annual
Report on Form 10-K has been signed below by the following persons on behalf of
the Registrant and in the capacities and on the dates indicated.


Date:  April 28, 2000                      /s/ George G. Usher
                                          -------------------------------------
                                          George G. Usher, Director, President
                                            and Chief Executive Officer
                                            (Principal Executive Officer)


Date:  April 28, 2000                      /s/ Sharon Wardlaw
                                          -------------------------------------
                                          Sharon Wardlaw, Treasurer, Secretary
                                            and Chief Financial and Accounting
                                            Officer (Principal Financial and
                                            Accounting Officer)


Date:  April 28, 2000                      /s/ Joseph Buchman
                                          -------------------------------------
                                          Joseph Buchman, Director


Date:  April 28, 2000                      /s/ Derek John Michael Lederer
                                          -------------------------------------
                                          Derek John Michael Lederer, Director


Date:  April 28, 2000                      /s/ John L.E. Seidler
                                          -------------------------------------
                                          John L.E. Seidler, Director


                                        -18-

<PAGE>

Date:  April 28, 2000                      /s/ Ruth L. Usher
                                          -------------------------------------
                                          Ruth L. Usher, Director


Date:  April 28, 2000                      /s/ Thomas C. Usher
                                          -------------------------------------
                                          Thomas C. Usher, Director


                                       -19-

<PAGE>

                                  EXHIBIT INDEX
<TABLE>
<CAPTION>

     Exhibit Number                 Exhibit Description
     --------------                 -------------------
     <S>                            <C>
            13                      Annual Report to Shareholders for the fiscal
                                    year ended January 31, 2000 (only those
                                    portions incorporated herein by reference)
            21                      Subsidiaries of Polydex Pharmaceuticals
                                    Limited
            27                      Financial Data Schedule
</TABLE>