SUPPLY AGREEMENT

         This Supply Agreement (this "Agreement"),  effective as of December 19,
1997,  is  by  and  between  Connetics   Corporation,   a  Delaware  corporation
("Connetics"  or  "SELLER"),  and  Pharmascience,  Inc., a Canadian  corporation
("BUYER");

                                   BACKGROUND

         A. The  parties  hereto have  entered  into a Canadian  Asset  Purchase
         Agreement  dated  December  18, 1997 (the "Asset  Purchase  Agreement")
         pursuant to which SELLER is  transferring  to BUYER  certain  rights in
         Canada to products known as Ridaura(R) containing auranofin as the sole
         active ingredient and assets relating thereto,  including  Canadian NDS
         File No.  9427-S1376/4-27,  Control No. 7HN906405,  issued on September
         12, 1985 (the "NDS");

         B. In  connection  with  Asset  Purchase  Agreement,  BUYER  desires to
         purchase Ridaura from SELLER in finished dosage form;

         C.  SELLER has entered  into a Final  Finished  Pharmaceuticals  Supply
         Agreement  with  SmithKline  Beecham  Pharmaceuticals,  a  division  of
         SmithKline   Beecham    Corporation,    a   Pennsylvania    corporation
         ("SmithKline") dated December 31, 1996, pursuant to which SmithKline is
         manufacturing   and  supplying   Ridaura  to  SELLER  (the  "SmithKline
         Agreement"); and

         D. Through its  relationship  with  SmithKline or other future vendors,
         SELLER  desires  to  supply  Ridaura  exclusively  in  Canada to BUYER,
         subject to the terms and conditions of this Agreement.


         NOW,  THEREFORE,  in  consideration  of the foregoing  premises and the
promises herein, the parties, intending to be legally bound, agree as follows:


                             ARTICLE 1 - DEFINITIONS

         1.1 Affiliate of an entity  means,  for so long as one of the following
relationships is maintained, any corporation or other business entity controlled
by,  controlling,  or under common control with no other entity;  with "control"
meaning direct or indirect beneficial ownership of more than fifty percent (50%)
of the  voting  stock of such  corporation,  or more than  fifty  percent  (50%)
interest in the decision-making  authority of such other unincorporated business
entity;






         1.2 cGMP shall mean  current good  manufacturing  practices of the U.S.
Food and Drug  Administration,  as set forth in 21 C.F.R.  Parts 210 and 211 and
all  applicable  rules,  regulations,  guides  and  guidances,  as  well  as all
applicable  rules,  regulations,  guides and  guidances of the  Canadian  Health
Protection Board;

         1.3 Product(s) shall mean Ridaura in finished dosage form.

         1.4 Territory shall mean Canada.

         1.5 Vendor  shall mean any  supplier of  Products to SELLER,  (with the
parties acknowledging that sole current Vendor is SmithKline).


               ARTICLE 2 - ORDERS, PRICING, PAYMENT AND ACCEPTANCE

         2.1 Sale of Products.  SELLER shall sell Product  exclusively  to BUYER
for sale in the  Territory  and,  to the  extent  that  SELLER  is able to order
Product from its Vendor, shall supply all of BUYER's reasonable  requirements of
Product in the  Territory.  SELLER will effect such sales by  including  BUYER's
reasonable requests for Products in SELLER's orders submitted to its Vendor(s).

         2.2 Forecasts and Orders.

             (a) By  September  1st  of  each  year  during  the  term  of  this
                 Agreement,  BUYER shall provide SELLER with a 12 month forecast
                 to run from January 1st to December  31st of the next  calendar
                 year of BUYER's  estimated  requirements of the Product,  which
                 forecast may be updated every three (3) months. The first three
                 (3)  months  of  each  rolling  12-month  forecast  or  updated
                 forecast  shall be a  binding  order  against  which  SELLER is
                 authorized to order Products from its Vendor.

             (b) Upon  receipt  of BUYER's  ordered  Products  from the  Vendor,
                 SELLER shall deliver such Products to BUYER in a timely manner.
                 SELLER may also, in its sole discretion,  request the Vendor to
                 deliver products directly to BUYER.

             (c) BUYER is not  obligated to buy any specific  amount of Products
                 under this  Agreement  and shall be obligated to purchase  only
                 those quantities for which it has submitted a binding order.

         2.3 Price; Payment; Shipment.

             (a) Except as  otherwise  agreed to between  BUYER and SELLER,  the
                 price for the Product  ordered  shall be the price

                                       2




                 charged  for the  Products  by the  Vendor to  SELLER.  For all
                 orders,  risk of loss in  transit,  either  from the  Vendor to
                 SELLER  or from  SELLER  to BUYER,  shall  lie with  BUYER.  In
                 addition,  for all orders,  BUYER shall be responsible  for all
                 out-of-pocket  charges,  taxes  and  other  costs  incurred  in
                 connection  with the  supply of  Products  to BUYER,  including
                 without  limitation all freight and shipping charges,  transfer
                 costs, and sales and import taxes, levies or duties;  provided,
                 that in the case of the  shipment  of Products to SELLER by the
                 Vendor,  BUYER  shall  only be  responsible  for  its pro  rata
                 portion of the costs  incurred by SELLER (i.e.,  the proportion
                 that BUYER's  quantity of Products  ordered  bears to the total
                 quantity of Products ordered by SELLER from the Vendor).

             (b) BUYER agrees to pay SELLER for the Products as set forth above,
                 net thirty (30) days from the receipt of invoice.  All payments
                 hereunder shall be made in U.S. Dollars.

         2.4 Acceptance. Within twenty-five (25) days of receipt of any Product,
BUYER shall perform such  samplings and tests as it deems  appropriate,  if any,
using validated test methods to determine  whether the Product meets the Product
specifications agreed to between SELLER and the Vendor (e.g., those set forth in
Exhibit A of the  SmithKline  Agreement)  (the  "Specifications").  SELLER shall
provide  certificates  of  analysis  for each batch of  Product,  as provided to
SELLER by the Vendor. If BUYER wishes to reject any shipment, BUYER shall within
such  twenty-five  (25) days' time,  inform  SELLER in writing of its refusal to
accept the lot(s),  and the reasons  therefor.  Any Product not timely  rejected
shall be deemed accepted. In the event that BUYER rejects any shipment,  SELLER,
upon  confirmation  of the  reasons  for  rejection,  shall  either  replace the
defective  Products or to refund the  purchase  price,  as SELLER may elect.  If
SELLER and BUYER do not agree on the rejection of Product, then either party may
refer the matter for final analysis to a specialized laboratory of international
reputation  reasonably acceptable to both parties for the purpose of determining
whether the Product meet  Specifications.  Any  determination by such laboratory
shall be binding upon both parties.

         2.5  Reservation of Rights.  Nothing in this  Agreement  shall prohibit
Pharmascience  from obtaining  Product from third parties or from  manufacturing
Product itself.


              ARTICLE 3 - WARRANTIES, COVENANTS AND INDEMNIFICATION

         3.1 Warranty Disclaimer and Indemnification.

             (a) SELLER  warrants  that its  current  agreement  with its Vendor
                 requires  that  the  Product  is and  will be  manufactured  in
                 accordance  with  United  States  cGMPs,  and  at the  time  of
                 delivery of the Product,  the Product will be free from defects
                 in materials and  workmanship  and shall not be  adulterated or
                 misbranded

                                       3




                 within the meaning of the U.S.  Federal Food, Drug and Cosmetic
                 Act,  and is not an article  which may not,  under the Act,  be
                 introduced into interstate commerce.  In addition,  SELLER will
                 use its best efforts to work with its Vendor to ensure that the
                 Product is sold and  manufactured  in accordance  with Canadian
                 cGMPS.  EXCEPT AS EXPRESSLY  STATED IN THIS  AGREEMENT,  SELLER
                 MAKES NO EXPRESS OR IMPLIED WARRANTY AS TO THE  MERCHANTABILITY
                 OF THE PRODUCT,  OR AS TO ITS FITNESS FOR A PARTICULAR  PURPOSE
                 AND DISCLAIMS ALL OTHER WARRANTIES,  EXPRESS OR IMPLIED.  BUYER
                 shall not be entitled to incidental,  indirect or consequential
                 damages, including damages from loss of profits, loss of use or
                 loss of  goodwill  as a result  of any  breach of  warranty  by
                 SELLER.

             (b) In the event that any Product is quarantined or recalled in the
                 Territory,  or is subject to stop-sale action in the Territory,
                 whether  voluntary or by governmental  action, it is agreed and
                 understood that any expenses,  including reasonable fees of any
                 experts or  attorneys  that may be  utilized  by either  party,
                 government   fines  or  penalties,   related  to  such  recall,
                 quarantine or  stop-sale,  shall be borne by BUYER unless it is
                 determined that SELLER has breached its obligations  under this
                 Agreement  and such  breach is the sole  basis  upon which said
                 recall,   quarantine   or   stop-sale   was   initiated.   Said
                 determination may be made by the governmental  agency involved,
                 or by mutual agreement of the parties following examination and
                 review  of all  records  pertinent  to the  manufacture  of the
                 Product subject to such recall.

             (c) SELLER  agrees  to  defend,  indemnify  and hold  BUYER and its
                 Affiliates,  directors,  employees and agents harmless from and
                 against any  claims,  liabilities,  damages,  costs or expenses
                 (including  reasonable  attorney's  fees)  resulting  from  any
                 claims by a third party arising  solely out of (i) the fault or
                 negligence of SELLER; or (ii) any material misrepresentation or
                 breach of warranty of SELLER  contained in this Agreement or in
                 any exhibit hereto,  or in any other statement,  certificate or
                 document  furnished or to be furnished to BUYER pursuant hereto
                 or in connection with the transactions  contemplated hereby; or
                 (iii) any material breach of a covenant or obligation of SELLER
                 contained  in  this  Agreement;   provided  however  that  this
                 indemnity  shall  exclude  indirect,  incidental,  indirect  or
                 consequential damages.

             (d) BUYER  agrees to  defend,  indemnify  and hold  SELLER  and its
                 Affiliates,  directors,  employees and agents harmless from and
                 against  any  claims,  liabilities,  damage,  costs or expenses
                 (including reasonable attorney's fees) resulting from any claim
                 except to the extent  that  SELLER is  otherwise  obligated  to
                 indemnify BUYER under this Agreement.

             (e) No party  against  whom a claim of indemnity is made under this
                 Agreement  shall be liable  unless the party  making such claim
                 shall (i)

                                       4




                 notify  the  indemnifying  party of such  claim  promptly  upon
                 becoming aware of the existence or threatened  existence of any
                 such claim  giving rise to or which may give rise to a claim of
                 indemnity and (ii) cooperate in the defense of such claim.

             (f) Notwithstanding any of the foregoing provisions of this Section
                 3.1, SELLER shall have no liability or obligation whatsoever to
                 BUYER for any claims,  liabilities,  damage,  costs or expenses
                 arising under any actions or omissions of the Vendor, including
                 without  limitation  actions  or  omissions  by the  Vendor  in
                 connection with the manufacture or shipment of the Products.

         3.2 Regulatory Matters.

(a)  BUYER  shall  maintain  the NDS in good  standing  during  the term of this
agreement.

             (b) SELLER  shall   maintain  all  United  States   regulatory  and
                 governmental  permits,  licenses  and  approvals  that  may  be
                 necessary to sell and ship the Product to BUYER.

             (c) BUYER shall maintain all Canadian  regulatory and  governmental
                 permits,  licenses  and  approvals  that may be  necessary  for
                 SELLER or its Vendor to sell and ship the Product to BUYER.

         3.3 Complaints and Recalls

             (a) Product  Complaints - Product complaint reports  concerning the
                 Product  received by BUYER will be faxed within 2 business days
                 (and then promptly sent via internationally-recognized courier)
                 to:

                 SmithKline Beecham Pharmaceuticals
                 One Franklin Plaza
                 Philadelphia, PA  19101
                 Attn: Karen Tannenbaum
                 Fax: (610) 917-4826

                 Connetics Corporation
                 3400 West Bayshore Road
                 Palo Alto, CA 94303
                 Attn:  Joel Henner
                 Fax: (650) 843-2899

                 and to any Vendor who has supplied Products to BUYER, including
                 through SELLER.

                                       5




             (b) SELLER will use commercially  reasonable efforts to ensure that
                 the Vendor promptly investigates all complaints associated with
                 the  manufacture of Product.  BUYER will  investigate all other
                 Product  complaints  associated  with the Product and provide a
                 written  summary  to  SELLER  and  any  Vendor.  To the  extent
                 requested  by  Connetics,  BUYER  also  will  provide a written
                 response on each complaint to each  complainant  with a copy to
                 SELLER and each Vendor.

             (c) Recalls - In the event SELLER or a Vendor should be required to
                 initiate a recall,  field alert,  Product  withdrawal  or field
                 correction   pursuant  to  any  Product   provided  under  this
                 Agreement, SELLER shall immediately notify BUYER in writing. In
                 the event  that  BUYER  believes  that a recall,  field  alert,
                 Product  withdrawal,  or  field  correction  is  necessary  for
                 Product  provided under this  Agreement,  BUYER shall so notify
                 SELLER.

         3.4  Adverse  Reaction  Reports  BUYER and SELLER  shall agree upon and
observe  procedures  and  notification  requirements  with  respect  to  adverse
reactions regarding the Product,  which shall be substantially  similar to those
contained in Exhibit D to the SmithKline Agreement.

         3.5  Insurance.  During  the term of this  Agreement,  SELLER and BUYER
shall maintain their own respective  comprehensive  general liability,  property
damage insurance,  and product liability  insurance with respect to the Product,
in such  amounts and with such scope of  coverage  as are  adequate to cover the
obligations  under this Agreement and as are  appropriate  for companies of like
size,  taking into account the scope of  activities  contemplated  herein.  Each
party shall, at the request of the other party, provide proof of such insurance.

         3.6  Acknowledgment  of  Change in  Manufacturing  Site.  BUYER  hereby
acknowledges that SmithKline,  SELLER's current vendor, has notified SELLER that
it intends to change the site of its  manufacturing  facilities  for the Product
and that such  change in  facilities  could  lead to delays in the  delivery  of
Products.  SELLER  shall bear no  obligation  or  liability  with respect to any
damages incurred by BUYER as a result of such delays.  In addition,  BUYER shall
obtain and maintain,  at its own cost and expense,  any Canadian  regulatory and
governmental permits, licenses and approvals that may be necessary in connection
with the SmithKline's change in manufacturing  facilities.  Should SELLER change
Vendors,  SELLER shall use its best efforts to have such Vendor's  manufacturing
site  registered in Canada as an approved site for the  manufacture  of Product.
BUYER shall bear any costs associated with such registration.

         3.7 Change of Bulk  Supplier.  In the event  that  SELLER  changes  the
Vendor who is its  supplier of bulk  auranofin,  SELLER  shall use  commercially
reasonable  efforts to have such new supplier submit all necessary  filings with
Canadian regulatory authorities,  including submitting a Drug Master File to the
Canadian Health Protection Branch.

                                       6




                        ARTICLE 4 - TERM AND TERMINATION

         4.1 This Agreement  shall have a term  commencing on the date first set
forth above and continuing so long as BUYER maintains an agreement with a Vendor
that allows BUYER to fulfill its obligations hereunder, unless this Agreement is
terminated sooner as provided in this Article 4

         4.2 Either party may terminate this Agreement by giving sixty (60) days
notice to the other party if the other  party is in material  breach of any term
of this  Agreement  and fails to cure that  breach  within  such  sixty (60) day
period.

         4.3 This Agreement may be canceled upon thirty (30) days' prior written
notice by either  party at any time  during  this  Agreement  if the other party
shall file in any court pursuant to any statute of any government in any country
a  petition  in  bankruptcy  or  insolvency  or  for  reorganization  or  for an
arrangement  or for the  appointment of a receiver or trustee of the party or of
its assets;  or if any other party  proposes a written  agreement of composition
for  extension  of its  debts;  or if the other  party  shall be served  with an
involuntary  petition against it, filed in any insolvency  proceeding,  and such
petition shall not be dismissed within sixty (60) days after filing thereof;  or
if the other party shall be a party to any dissolution or liquidation, or if the
other party shall make a general assignment for the benefit of its creditors; or
if the other  party is  subject  to any final  order of  debarment  which can be
expected to have a material adverse effect on the sales of the Product.

         4.4 Upon termination, SELLER or its Vendor will deliver and BUYER shall
promptly pay SELLER for all ordered Products.


                            ARTICLE 5 - MISCELLANEOUS

         5.1 Corporate  Organization  and Authority.  Each party  represents and
warrants  that it is a company duly  organized,  validly  existing,  and in good
standing under the laws of the jurisdiction wherein it is organized, and that it
has all necessary power and  authorization to assume the obligations  under this
Agreement, and to discharge them pursuant to the terms hereof.

         5.2 Force  Majeure.  Neither party shall be liable to the other if, and
to the  extent,  that the  performance  or delay  in  performance  of any of its
obligations under this Agreement is prevented, restricted, delayed or interfered
with  due  to  circumstances  beyond  the  reasonable  control  of  such  party,
including,   but  not  limited  to,  government   legislation,   fires,  floods,
explosions, epidemics, accidents, acts of nature, wars, riots, strikes, lockouts
or other concerted acts of workers and/or acts of government. The party claiming
an event of force majeure shall promptly notify the other party in writing,  and
provide full  particulars of the cause or event and the date of first occurrence
thereof,  as soon as  possible  after the  event  and also keep the other  party
informed of any further  developments.  The party so affected shall use its best
efforts  to remove  the cause of  non-performance,  and both the  parties  shall
resume performance hereunder

                                       7




with the utmost  dispatch  when such cause is removed  unless this  Agreement is
previously expired or terminated under Article 4 hereof.

         5.3  Amendment  and Waiver.  This  Agreement  may be amended  only by a
writing  which  specifically  states that such an  amendment  is its purpose and
which is signed by both  parties.  No course of dealing  between  the parties or
failure  by  either  party to  exercise  any  right or  remedy  hereunder  shall
constitute  an  amendment  to this  Agreement  or a waiver of any other right or
remedy or the later exercise of any right or remedy.

         5.4 Governing Law. This Agreement shall be governed by and construed in
accordance with the substantive law of the State of California,  U.S.A.  without
regard to its rules for conflicts of law.

         5.5 Successors and Assigns.  The provisions of this Agreement  shall be
binding upon and inure to the benefit of the parties hereto and their respective
successors and assigns; provided, however, that no party may assign, delegate or
otherwise transfer any of its rights or obligations under this Agreement without
first  receiving  the prior  written  consent of the other  party  hereto  which
consent shall not be unreasonably withheld,  except that either party may assign
and delegate its rights and duties hereunder  without obtaining such consent (i)
to any  Affiliate or  subsidiary  of such party,  or (ii) to any party or entity
which acquires substantially all of the business or assets of such party if such
party  guarantees the performance of the acquiring party and the acquiring party
expressly assumes the assigning party's obligations hereunder.

         5.6 Nature of Agreement.  In operating under the Agreement,  each party
shall act  independently  and this Agreement  shall not be construed as creating
any partnership,  joint venture or incorporated  business entity.  Neither party
shall have any  authority to incur any  liability or  obligation  whatsoever  on
behalf of the other.

         5.7  Notice.  Any notice,  direction  or other  instrument  required or
permitted to be given to SELLER  hereunder  shall be in writing and may be given
by delivering the same,  via  internationally-recognized  courier,  addressed to
SELLER as follows:

                 To:           Connetics Corporation
                               3400 W. Bayshore Road
                               Palo Alto, CA  94303
                               Attn: Chief Executive Officer

                 Copy to:      Venture Law Group
                               2800 Sand Hill Road
                               Menlo Park, CA  94025
                               Attn:  Joshua L. Green
                               Fax:  (650) 233-8386

                                       8




                  Any  notice,   direction  or  other  instrument   required  or
permitted to be given to BUYER hereunder shall be in writing and may be given by
delivering the same, via internationally-recognized  courier, addressed to BUYER
as follows:

                 To:           Pharmascience, Inc.
                               8400 Darnley Road
                               Montreal, Quebec
                               H4T 1M4
                               Attn:  Chairman of the Board

                Any such notice,  direction or other  instrument,  if delivered,
shall be deemed to have been given on the date on which it was delivered.

                Any party hereto may change its address for service from time to
time by  notice  given  to the  other  parties  hereto  in  accordance  with the
foregoing.

         6.8 Entire  Agreement.  This Agreement and the agreements and documents
referred  to  herein   constitute  the  entire  agreement  between  the  parties
pertaining to the subject  matter hereof,  and supersede,  on the effective date
hereof,  all  prior  and   contemporaneous   agreements,   representations   and
understandings of the parties in connection  herewith.  No agent of either party
is authorized to make any representation,  promise, or warranty not contained in
this Agreement.


                            [Signature Page Follows.]


                                       9




         IN WITNESS  WHEREOF,  this  Agreement  has been executed by the parties
hereto as of the date first written above


                                        PHARMASCIENCE, INC.


                                        By: /s/ PharmaScience, Inc.  (signature)
                                            ------------------------------------
                                        Name:
                                             -----------------------------------
                                        Title:
                                              ----------------------------------


                                        CONNETICS CORPORATION


                                        By: /s/ Thomas G. Wiggans    (signature)
                                            ------------------------------------
                                        Name:
                                             -----------------------------------
                                        Title: President and Chief Executive 
                                              ----------------------------------
                                               Officer
                                              ----------------------------------

                                       10