RAW MATERIAL CONTRACT
                             EDIBLE BOVINE CORIUM
                           MedChem Part No. 100-016
                                April 18, 1995


The Lackawanna Leather Company, a division of United States Leather, Inc., 2420
Z Street, Omaha, Nebraska, 68107, hereinafter called "Seller", agrees to sell,
and MedChem Products, Inc., 232 West Cummings Park, Woburn, Massachusetts,
01801, hereinafter called "Buyer", agrees to buy, the following described
product subject to the terms and conditions herein set forth:

I.   PRODUCT
     -------

     Edible Bovine Corium obtained from cattle with an origin in the United
     States of America and an XXX XXXXXXXXX XXXXX XX XXXXX XX XX XXXX XXXX XXXX
     XXXXX. of extract made in accordance to Buyer's procedure DCN 94-022 for
     Edible Bovine Corium, as set forth on Exhibit A attached hereto, which
     shall be separately acknowledged and agreed to by each, the Seller and
     Buyer (the "Specifications".)

II.  WARRANTY
     --------

     Seller warrants that the product delivered hereunder shall meet all
     Specifications, shall be produced in accordance with applicable GMP's and
     all other procedures identified by Buyer (pursuant to Article VIII 10) and
     shall be free of liens and encumbrances.  This is the sole warranty
     provided by Seller and Buyer acknowledges that Seller hereby disclaims any
     implied warranties under the Uniform Commercial Code.

III. LIMITATION OF LIABILITY
     -----------------------

     Notwithstanding anything to the contrary contained herein and solely as it
     applies to pyrogen specification, Seller shall not be liable to Buyer for
     failing to produce products which meet the pyrogen specification identified
     on Exhibit A so long as the failure to meet such specification does not
     result from Seller's failure to meet all Specifications or to produce the
     product in accordance with applicable GMP's and all other procedures
     identified by Buyer (pursuant to Article VIII 10).  In the event that Buyer
     does not accept product because such product does not meet the pyrogen
     specification, Buyer shall be liable to Seller for the invoice cost of the
     hides purchased and used to make such product.


(X) Confidential material omitted and filed separately with the Securities and 
    Exchange Commission.


 
IV.  PRICE AND QUANTITY
     ------------------

     1.   Subject to the terms of this Agreement, Buyer agrees to purchase and
          Seller agrees to furnish an aggregate of XXXXXX pounds of product over
          the course of this contract.  Additional quantity is negotiable upon
          Seller's ability to produce more product, and Buyer's desire to
          purchase a greater quantity.

          For the  purposes of this agreement, all weights refer to wet Edible
          Bovine Corium weight at the time of packaging at the Seller's Omaha,
          Nebraska, facility.

     2.   Delivery schedule is defined in Article VI below.

     3.   Price per pound is:

                XXXXXX   per pound
                 XXXXX   per pound payback of advance for start-up costs
                ------                                                   
                XXXXXX   per pound net price.

     4.   Start-up costs of XXXXXXX will be advanced to the Seller by the later
          of (i) 30 days after notice of the equipment renovation and (ii) 15
          days after the date buyer receives an invoice for such advance.
          During the start-up, the Seller will replace an existing Challenge
          Mixer with a stainless steel mixer that is currently owned by the
          Seller.

          Title to the new stainless steel mixer will pass to the Buyer after
          installation free and clear of encumbrances.  Title to the existing
          Challenge Mixer will pass to the Seller, free and clear of
          encumbrances.

          Seller shall pay back the advance of XXXXXXX by crediting the Buyer
          with XXXXX per pound for each pound sold hereby as shown in Paragraph
          3 above.

          Up front start-up costs for which the advance may be used shall
          include the following:

                                                                
          - Lease and install Reverse Osmosis Pure Water System    XXXXXXX.XX
          - Trade Challenge Mixer for stainless steel mixer          XXXXX.XX
          - Splitting machine servicing                              XXXXX.XX
          - Cleaning and painting materials                          XXXXX.XX
          - Cleaning and painting labor(80 hrs @ XXXXXXXX)             XXX.XX
          - Freezer and air conditioner start-up                       XXX.XX
          - Calibration of temperature recorders                       XXX.XX
                                                                   ----------
                                                                   XXXXXXX.XX  


(X) Confidential material omitted and filed separately with the Securities and 
    Exchange Commission.

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     5.   The price per pound includes and Seller shall pay, all excise, sales,
          use, transfer or other taxes, federal, state and local, in connection
          with the sales or delivery of the product to Buyer.

V.   TITLE OF EQUIPMENT
     ------------------

     All equipment purchased with the advance shall be retained by Buyer as its
     property.  Buyer recognizes that Seller may use this equipment during the
     term of this Agreement for processing and products for other customers.
     However, the Seller must obtain prior written approval from the Buyer for
     each use.  Seller hereby agrees to maintain this equipment in serviceable
     condition during each use.

VI.  DELIVERY SCHEDULE AND TERMS OF PAYMENT
     --------------------------------------

     Each lot of product must meet acceptable Quality Control inspection
     criteria of the Buyer before being transferred from the Seller's Omaha,
     Nebraska location to the Massachusetts cold storage location.

     Seller Will:

     1.   Deliver a XXX pound sample lot to Buyer on or before July 15, 1995.
          The purpose of this shipment is to verify that the product is able to
          be processed into flour at Buyer's manufacturing facility at Woburn,
          Massachusetts.

     2.   Deliver XXXXX pounds to the Massachusetts cold storage facility by
          August 31, 1995.  Deliver the remaining XXXXXX pounds on or before
          December 31, 1995.

     3.   a.   Seller will also invoice Buyer on a monthly basis and Buyer
               will pay such invoices within 15 days from the date that the
               Buyer receives Seller's invoices; Invoices shall be as of the 1st
               of the month as sent by Seller as follows:

               i.   For the eight (8) month period August 1995 through March
                    1996 invoiced at the rate of XXXX pounds per month.

               ii.  For the twenty (20) month period April 1996 through November
                    1997 at the rate of XXX pounds per month.

          b.   Unless the parties agree otherwise in writing, Seller must
               deliver the exact quantities specified (plus or minus 1%).  Buyer
               reserves the right to reject incomplete deliveries and to return
               at Seller's risk and expense excess quantities delivered.

(X) Confidential material omitted and filed separately with the Securities and 
    Exchange Commission.



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          c.   Buyer's production and marketing schedules are established in
               part in reliance upon the delivery information specified in this
               Agreement.  If delivery cannot be made at the specified time and
               place, Seller shall promptly notify Buyer of the earliest
               possible date for a conforming delivery.  Notwithstanding such
               notice, and unless otherwise agreed by Buyer in writing, Seller's
               failure to effect a conforming delivery shall entitle Buyer to
               revoke any acceptance, to terminate the Agreement without
               liability to Seller, to receive a full refund on any amount paid
               with respect to such shipment, to purchase substitute products
               elsewhere, to return at Seller's risk and expense all or any part
               of a nonconforming delivery and to hold Seller accountable for
               any loss or additional costs incurred.

               Buyer's receipt of acceptance of all or a part of a nonconforming
               delivery shall not constitute a waiver of any claim, right or
               remedy under the Agreement or under applicable law.

VII. SERVICES TO BE PROVIDED BY SELLER AT SELLER'S EXPENSE
     -----------------------------------------------------

     1.   Appropriate clean facility satisfying GMP to conduct production.

     2.   Obtaining hides.

     3.   Processing hides.

     4.   Quality Control services by a sub-contractor approved by Buyer.

     5.   Training of Seller's work force.

     6.   Hiring of all labor and support people to manage the activity.

     7.   Setup and maintenance support for equipment to include calibrations.

     8.   Temporary cold storage of product at:

          - Omaha, Nebraska

          Temperature will be monitored and recorded. Temperature to be
          maintained in the range of -20 degrees F to +10 degrees F (monitoring
          specifications are attached hereto in Appendix A).

     9.   Supplying pure water through a leased Reverse Osmosis System.

     10.  Disposal of all waste in accordance with governmental and industry
     regulations.

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     11.  Freight charges to deliver product to Massachusetts cold storage 
          facility (monitoring specifications are attached hereto in 
          Appendix A).

     12.  Insure product for loss while in transit.


VIII.  GENERAL TERMS
       -------------

     1.   Seller will identify each container of Edible Bovine Corium with the
          gross weight of the contents of the container, MedChem Part number
          100-016 and Lot #_____.  All products shall be packaged, marked and
          otherwise prepared for shipment by Seller in suitable containers in
          conformity with reasonable commercial practices.  Seller shall mark on
          containers all necessary handling, loading and shipping instructions.
          An itemized packing list shall be included with each shipment.

     2.   Seller will provide a certificate of origin with each Lot # delivered
          to Buyer.  This certificate will verify that the cattle, from which
          the product was harvested, had an origin in the United States of
          America.

     3.   For the term of the contract, arrangement and cost of refrigerated
          transportation of the product to the storage facility at Crystal Cold
          Storage and Warehouse, Inc., 25 Sycamore Avenue, Medford,
          Massachusetts, 02155, will be the responsibility of the Seller.
          Temperature will be monitored in transit and will be maintained
          between -20 degrees F and +10 degrees F (monitoring specification as
          attached hereto in Appendix A).

     4.   Title to product sold hereunder shall pass to Buyer upon delivery by
          Seller of conforming product and acceptance by Buyer at Crystal Cold
          Storage and Warehouse.

     5.   Seller agrees that Buyer, its agents and representatives, including
          but not limited to, Buyer's insurance representatives and
          underwriters, may inspect Seller's Omaha, Nebraska premises in a
          reasonable manner, with reasonable frequency, and for reasonable
          periods of time, for the purpose of monitoring the manufacture of the
          product and compliance with the terms of the Agreement and, for the
          purpose of rendering insurance advice to the Buyer in connection with
          this Agreement.

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     6.   All products shall be received subject to Buyer's inspection, testing,
          and approval at Seller's premises, and subject to Buyers's acceptance
          of such products at Crystal Cold Storage and Warehouse after
          inspection and testing of the conditions of such products after
          shipping, notwithstanding any prior payment for such products.  The
          test, lab and any other inspection data;recorder data during initial
          testing, warehousing and transit will be provided to Seller by Buyer
          to perfect Buyer's claim for product rejected by Buyer upon inspection
          and testing at the Crystal Cold Storage and Warehouse.

          Upon a rejection of such a shipment and notice of said rejection by
          Buyer to Seller it shall be Seller's responsibility to adjust its
          production schedule to replace such rejected product within the
          delivery parameters specified under Article VI 3.  Products rejected
          by Buyer as not conforming to the Specifications may be returned to
          Seller at Seller's risk and expense.

     7.   Seller's warranties under Article II of this Agreement shall survive
          any delivery, inspection, acceptance, payment or resale of the
          products and shall extend to Buyer and its customers.  Following such
          delivery, inspection, acceptance, payment or resale of such products
          and notwithstanding anything to the contrary set forth herein, Seller
          shall only be liable with respect to such products in connection with
          any breach of its warranties in Article II of this Agreement.  Seller
          shall indemnify and hold Buyer harmless against any and all claims,
          losses, liabilities, damages, costs or expenses, including attorneys'
          fees and court costs, resulting from the breach of Seller's Article II
          Warranty(s) under this Agreement.  Seller and Buyer shall each
          maintain with an insurance company or companies comprehensive general
          liability insurance (including product liability hereunder) in the
          minimum amount of $2,000,000.  Any amount owed to Seller by Buyer
          shall be subject to deduction for any set-off, counterclaim or
          indemnification right arising out of this Agreement.

     8.   Sellers' liability to Buyer for breach of warranty or otherwise shall
          not include any incidental or consequential damages.

     9.   Notwithstanding anything to the contrary contained in this agreement,
          neither party will be liable for any default, damages or expenses
          under this agreement as a result of such party's failure to perform
          its duties under this Agreement, due to interruptions of the supply of
          raw materials, complete or partial destruction of the
          manufacturing/processing facilities, labor disputes and other matters
          reasonably beyond the control of either party; provided, however, that
          the party claiming the foregoing shall make a good faith effort to
          remedy any of the above contingencies. In such event, the time for
          performance shall be extended for the period of delay or inability to
          perform due to such event. During any period of shortage, Seller's
          first obligation will be to supply Buyer with its requirement as
          outlined in the PRICE AND QUANTITY section of this agreement.

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     10.  The product will be manufactured in conformance with the
          Specifications.  However, the Buyer shall have the right to change the
          Specifications as reasonably desired by Buyer or as required by
          Federal regulations upon prior written notice to Seller provided that
          Buyer shall reimburse  Seller for any reasonable additional costs
          incurred by Seller in meeting such revised Specifications.  Seller may
          not make any changes in the Specifications without the prior written
          approval of the Buyer.

     11.  This agreement gives no license to Seller, either expressed or
          implied, under any patents, patent applications or other intellectual
          property of Buyer or under which Buyer has a right to grant licenses.

     12.  Seller acknowledges and agrees that all specifications, drawings,
          diagrams, schematics, sketches, models, samples, designs, technical
          information or data, written, oral or otherwise, furnished by Buyer to
          Seller is and shall remain Buyer's sole and exclusive property, and
          shall be returned promptly to Buyer upon the earlier of its request or
          the termination or completion of the agreement.  Seller acknowledges
          and agrees that all such intellectual and industrial property shall be
          treated as confidential and shall not be used or disclosed by Seller
          except under this Agreement.  Buyer further represents and warrants
          that the products delivered hereunder do not infringe any United
          States or foreign patent trademark, trade secret or copyright or any
          proprietary, intellectual property, industrial property, contract or
          other right held by any third party.

     13.  This agreement (other than the first two sentences of Section 12)
          shall terminate within  30   days after Seller has invoiced Buyer for
                                 -----                                         
          all of the product required to be delivered by this Agreement unless
          sooner terminated by Buyer and may be extended upon mutual agreement
          of the parties.  This agreement is not transferable nor assignable by
          Buyer or Seller without the prior written consent of the other party,
          but shall be binding upon and inure to the benefit of the parties
          hereto and their respective successors.

     14.  All notices to be provided hereunder shall be in writing, and shall be
          deemed given when addressed to a party hereto at the address set forth
          above, when deposited with the U.S. Mail, registered or certified, or
          when deposited with a nationally recognized overnight courier service.

     15.  This Agreement is to be governed by the laws of the State of Nebraska.

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     16.  Termination:
          ------------

          (a)  Buyer may, by written notice to Seller, terminate the whole or
               any portion of this Agreement in the event of (i) proceedings,
               voluntary or involuntary, in bankruptcy or insolvency, by or
               against Seller, (ii) the appointment, with or without Seller's
               consent, of any trustee or receiver for any substantial portion
               of Seller's assets, (iii) any assignment for the benefit of
               Seller's creditors, or (iv) Sellers' breach of any provision
               contained herein; Provided that in the event of a breach by
               Seller of any provision contained herein, Seller shall have 30
               days from notice by Buyer to cure such breach and this Agreement
               shall only be terminable to the extent that such breach is not
               cured by such 30 day period.  In the event of any such
               termination, Buyer may procure, upon such terms and in such
               manner as it may deem appropriate, products comparable to the
               products covered by the Agreement so terminated, and Seller shall
               be liable to Buyer for any excess cost of such comparable
               products.  In the event of any such termination, Buyer may
               require Seller to deliver to it, in the manner and to the extent
               directed by it, any completed or partially completed products,
               against Buyer's payment of the portion of the price properly
               allocable to such products.  Seller shall continue performance of
               this Agreement to the extent not terminated.  Except to the
               extent specifically set forth herein, Buyer shall have no
               obligation or liability to Seller in respect of the terminated
               portion of this Agreement.  Notwithstanding the foregoing, Seller
               shall not be liable to Buyer for excess costs or other damages if
               Seller's default is due to a cause beyond its reasonable control
               and without its negligence.  Such notice shall be in writing and
               mailed by U.S. Mail addressed to the Seller, and the date of
               notice shall be the date of mailing.  In the event of any such
               termination, all deposits or prepayments shall be deemed to have
               been held in trust for Buyer's benefit and shall be returned to
               Buyer promptly upon request.

          (b)  Subject to Section 7 hereof, all of Seller's representation,
               warranties and indemnification obligations set forth in this
               Agreement shall survive the cancellation, termination or
               completion of this Agreement with respect to any product sold to
               Buyer prior to cancellation, termination or completion.

                                       8

 
     17.  Compliance with Laws:
          ---------------------

          Seller shall comply with all applicable governmental laws, ordinances,
          codes, rules, regulations and orders in the performance of this
          Agreement, including, without limitation, the Occupational Safety and
          Health Act, the Fair Labor Standards Act of 1938, Title VII of the
          Civil Rights Act, the Age Discrimination in Employment Act, and
          Executive Order 11246, along with the implementing rules and
          regulations of the office of Federal Contracts Compliance.  At Buyer'
          request, Seller shall obtain all permits or licenses required in
          connection with the manufacture, sale, shipment and installation of
          the products ordered hereby.

     18.  Authorization:
          --------------

          Seller represents and warrants that it has been duly authorized to
          execute, deliver and perform this Agreement, and the person signing on
          Seller's behalf has the power and authority to do so.

     19.  Severability; Remedies; Waiver:
          -------------------------------

          In the event that any one or more provisions contained in this
          Agreement shall be held by a court of competent jurisdiction to be
          invalid, illegal or unenforceable in any respect, the validity,
          legality and enforceability of the remaining provisions contained
          herein shall not in any way be affected or impaired thereby.  The
          remedies contained herein are cumulative and in addition to any other
          remedies at law or equity.  Buyer's failure to enforce, or waiver of
          a breach of, any provision of this Agreement shall not constitute a
          waiver of any other breach of such provision.

     20.  Entire Agreement:
          -----------------

          This Agreement is the complete and exclusive statement of the contract
          between Buyer and Seller with respect to Buyer's purchase of the
          products.  No waiver, consent, modification, amendment or change of
          the terms of this Agreement shall be binding unless in writing and
          signed by Buyer and Seller.


All of the foregoing is accepted as of the date set forth above.

MEDCHEM PRODUCTS, INC.                     LACKAWANNA LEATHER

By:   /s/ Edward J. Quilty                 By:    /s/ Jeff Whitver
   ----------------------------------          -------------------------------

Date:                                      Date:  4/18/95
      -------------------------------            -----------------------------


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