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                                                                    EXHIBIT 10.4


CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR CERTAIN REDACTED PROVISIONS OF
THIS AGREEMENT. THE REDACTED PROVISIONS ARE IDENTIFIED BY THREE ASTERISKS AND
ENCLOSED BY BRACKETS. THE CONFIDENTIAL PORTION HAS BEEN FILED SEPARATELY WITH
THE SECURITIES AND EXCHANGE COMMISSION.


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                              COMMERCIAL AGREEMENT


                                 BY AND BETWEEN

                             ANSYS DIAGNOSTICS, INC.

                                       AND

                         ROCHE DIAGNOSTIC SYSTEMS, INC.

                                      DATED

                                  APRIL 1, 1993


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                              COMMERCIAL AGREEMENT

This Agreement, effective as of April 1, 1993 by and between Roche Diagnostic
Systems, Inc. ("RDS"), a corporation organized and existing under the laws of
the State of New Jersey with offices at 1080 Highway 202 Branchburg, New Jersey,
08876, and ANSYS, Inc. ("ANSYS") (formerly known as Toxi-Lab, Inc.), a
corporation organized and existing under the laws of the State of California
with offices at 2 Goodyear, Irvine, California, 92718.

         WHEREAS, RDS is engaged in the business of research, development,
marketing and sales of various products used in the field of in vitro
immunoassay and chromatography diagnostics; and

         WHEREAS, RDS owns certain proprietary information, materials,
intellectual property, technology and products relating to drugs of abuse
testing; and

         WHEREAS, ANSYS owns certain proprietary information and technology
relating to the design, manufacturing and packaging of, in vitro diagnostic
products; and

         WHEREAS, RDS and Toxi-Lab, Inc. entered into a Design and Feasibility
Agreement, dated November 15, 1992, under which RDS and Toxi-Lab, Inc.
collaborated in research activities to determine the feasibility of developing
new diagnostic products utilizing Toxi-Lab's and RDS's technology; and

         WHEREAS, under the Design and Feasibility Agreement, RDS and Toxi-Lab,
Inc. developed a new device that can hold, transport, sample and test various
fluids for chemical and biological analytes, including drugs of abuse utilizing
RDS's technology; and

         WHEREAS, Toxi-Lab, Inc. caused its corporate name to be changed to
ANSYS, Inc. effective March 5, 1993;

         WHEREAS, RDS has agreed to pay ANSYS a fee as provided herein to
further develop and optimize the new device for RDS; and

         WHEREAS, RDS has agreed to make ANSYS its exclusive manufacturer and
supplier for the new device; and

         WHEREAS, in consideration of RDS paying ANSYS a developmental fee,
making ANSYS its exclusive manufacturer and supplier of the new device, and
giving ANSYS certain licensing rights to the new device, ANSYS has agreed to
assign to RDS all its rights to such new device.

         NOW, THEREFORE, in consideration of the premises and of the mutual
covenants of the parties set forth herein, the parties agree as follows:


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1.0      DEFINITIONS

         1.1      "Affiliate" shall mean:

                  (a)      a business entity which owns, directly or indirectly,
                           a controlling interest in RDS, by stock ownership or
                           otherwise; or,

                  (b)      a business entity which is owned by RDS, either
                           directly or indirectly, by stock ownership or
                           otherwise; or,

                  (c)      a business entity, the majority ownership of which is
                           directly or indirectly common to the majority
                           ownership of RDS.

Anything to contrary in this paragraph notwithstanding, Genentech, Inc., a
Delaware corporation, shall not be deemed an Affiliate of RDS.

         1.2      "Confidential Information" shall mean a party's technology,
                  data, know-how, or information whether technical or
                  non-technical, financial statements and reports, pricing,
                  trade secrets, secret processes, formulas and customer data
                  (including customer lists), and the like, that is disclosed to
                  the other party and which at the time of disclosure is clearly
                  marked as "Confidential." Oral communications shall be
                  considered Confidential Information provided that such
                  communication is reduced to writing, marked as "Confidential"
                  and provided by the disclosing party to the other party within
                  thirty (30) days after such oral disclosure.

         1.3      "No-Step Kit" shall mean the device developed by RDS and ANSYS
                  under the Design and Feasibility Agreement dated November 15,
                  1992, that can hold, transport, sample and test various fluids
                  for biological and chemical analytes, including, without
                  limitation, certain drugs of abuse through the utilization of
                  RDS's Reagent Technology. The product specifications for the
                  No-Step Kit are set forth on Exhibit A, which RDS may, at its
                  sole option, modify from time to time. A copy of Exhibit A is
                  attached hereto and made a part hereof.

         1.4      "RDS Reagent Technology" shall mean the products, reagents,
                  patents, patent rights, technology, manufacturing methods and
                  processes, formulas, designs, technical data, product
                  development and research data, know-how, secret processes,
                  trade secrets, intellectual property rights, quality control
                  and quality assurance protocols, and the like, owned or
                  controlled by RDS that can be used to test for certain drugs
                  of abuse through the use of immunoassay and chromatography
                  technology.

         1.5      "RDS" shall mean Roche Diagnostic Systems, Inc. and its
                  Affiliates.


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2.0      OWNERSHIP AND PATENT RIGHTS

         2.1      Ownership. (a) RDS shall own the entire right, title and
                  interest in and to the RDS Reagent Technology and ANSYS shall
                  have no right, title or interest therein.

                           (b) RDS shall own the entire right, title and
                  interest in and to the No-Step Kit, and ANSYS shall have no
                  right, title or interest therein, except as provided in
                  Article 6 of this Agreement.

         2.2      Patent Applications. (a) ANSYS shall prepare and file the
                  necessary patent applications to protect any and all
                  patentable inventions relating to the No-Step Kit. ANSYS shall
                  assign to RDS, in such patent applications, any and all of its
                  rights to such inventions.

                           (b) ANSYS shall not file any such patent applications
                  without RDS's prior written approval, and ANSYS shall make any
                  changes requested by RDS to the applications before the filing
                  thereof.

         2.3      Additional Patent Rights to the No-Step Kit. In the event that
                  during the term of this Agreement, or any renewal thereof, an
                  invention is made relating to the No-Step Kit that results in
                  additional patentable rights to such product, then the
                  following provisions shall apply.

                  (a)      All such additional patent rights shall belong to RDS
                           regardless of whether it was developed by (i) RDS,
                           (ii) ANSYS, or (iii) jointly by RDS and ANSYS.

                  (b)      In the event that the additional patent rights are
                           developed (i) jointly by ANSYS and RDS, or (ii)
                           solely by ANSYS, then ANSYS shall prepare and file
                           the necessary patent applications to protect such
                           additional patent rights. ANSYS shall assign to RDS,
                           in such patent applications, all of its rights to
                           such inventions.

                  (c)      ANSYS shall not file any such patent applications
                           without RDS's prior written approval, and ANSYS shall
                           make any changes requested by RDS to the applications
                           before the filing thereof.

                  (d)      RDS shall (i) pay for all reasonable expenses
                           associated with the preparation and filing of any
                           patent application provided for in this Section 2.3
                           and Section 2.2, (ii) pay for the maintenance of any
                           patents issued, and (iii) reimburse ANSYS for any
                           reasonable expenses incurred by ANSYS in connection
                           with the preparation and filing of the application.
                           Such reimbursement shall be in addition to the fees
                           that RDS shall pay ANSYS under Section 3.1(c).


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         2.4      Other Patent Rights. If a patent application is filed or
                  issues in connection with activities performed under this
                  Agreement or any renewal thereof, that does not cover the
                  No-Step Kit and thus is not covered by the Section 2.3, but
                  that relates to inventions arising from or relating to the
                  development or manufacture of the No-Step Kit then this
                  Section shall apply.

                  (a)      Patent rights to such invention resulting solely from
                           the efforts of RDS shall be owned solely by RDS and
                           any such invention shall be promptly disclosed in
                           writing by RDS to ANSYS.

                  (b)      Patent rights to an invention resulting solely from
                           the efforts of ANSYS shall be owned solely by ANSYS
                           and any such invention shall be promptly disclosed in
                           writing by ANSYS to RDS.

                  (c)      Patent rights to an invention resulting from the
                           collaborative efforts of both parties shall be
                           jointly owned by the parties.

3.0      DEVELOPMENT, MANUFACTURE AND SUPPLY OF THE NO-STEP KITS

         3.1      Development. (a) ANSYS shall work in collaboration with RDS to
                  further develop and optimize the No-Step Kit for RDS which
                  shall include optimizing the design of the No Step Kit,
                  completing product development, initiating production
                  activities, and manufacturing and supplying RDS with various
                  prototypes of the kit for preclinical and clinical studies and
                  other applications.

                           (b) ANSYS shall use its best efforts to complete, to
                  the satisfaction of RDS, any activities that RDS requests
                  ANSYS perform under this Section. ANSYS shall not on its own
                  initiate any activities hereunder without receiving prior
                  written approval from RDS.

                           (c) In consideration of the services that ANSYS will
                  provided under this Section 3.1, RDS shall pay ANSYS a monthly
                  fee of $[***], for each month that ANSYS is performing
                  services hereunder, or a pro rata portion thereof, but in no
                  event shall RDS pay ANSYS more than $[***] to further develop
                  and optimize the No-Step Kit for RDS. Notwithstanding that
                  ANSYS will receive a maximum of $[***] for performing services
                  under this Section, ANSYS shall continue to work on and
                  complete the development and optimization of the No-Step Kit
                  until it meets the product specifications listed on Exhibit A,
                  even if it takes more than eight (8) months to accomplish.

[***]    Confidential treatment has been requested for the bracketed portions.
         The confidential redacted portion has been omitted and filed separately
         with the Securities and Exchange Commission.


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                           (d) In the event that RDS makes substantial changes
                  to the product specifications listed on Exhibit A, after
                  August 1, 1993 but before the first commercial manufacturing
                  of the product pursuant to Section 3.6, the fees and time
                  schedule stated herein shall be renegotiated in good faith by
                  the parties.

                           (e) ANSYS shall not start manufacturing the No-Step
                  Kit for RDS pursuant to Section 3.6 until: (i) all the
                  services requested herein by RDS have been completed by ANSYS,
                  to the satisfaction of RDS; (ii) pricing for the No-Step Kit
                  has been finalized by the parties pursuant to Section 3.5; and
                  (iii) ANSYS receives written notice from RDS to proceed with
                  such manufacturing and supply.

         3.2      Government Approvals. (a) RDS shall have the responsibility
                  for securing and maintaining governmental approvals to market
                  and sell the No-Step Kit. RDS shall, in its sole discretion,
                  determine in which countries it will pursue, and discontinue
                  the pursuit of, such governmental approval.

                           (b) ANSYS shall assist RDS, as requested by RDS, in
                  securing and maintaining such governmental approvals for the
                  No-Step Kit. ANSYS's assistance may include conducting studies
                  and providing to RDS data or other information required or
                  requested by the governmental authorities and assisting in the
                  completion and filing of applications and other forms
                  necessary for such governmental approvals.

                           (c) RDS shall be responsible for paying all costs
                  associated with obtaining such governmental approvals and
                  shall reimburse ANSYS for any costs incurred by ANSYS in
                  connection with such activities.

         3.3      Manufacturing Equipment. (a) ANSYS shall be responsible for
                  selecting and purchasing the equipment and materials,
                  including product designs, necessary to manufacture the
                  No-Step Kits. ANSYS shall not purchase any equipment or
                  materials without RDS's prior written approval.

                           (b) RDS shall pay for all equipment and materials,
                  including product designs, that it approves the purchase
                  thereof under Section 3.3(a). Upon such payment, RDS shall own
                  the entire right, title and interest to such equipment and
                  materials, and ANSYS shall have no right, title or interest
                  therein, except to use such equipment and materials to
                  manufacture and supply the No-Step Kit to RDS pursuant to the
                  terms of this Agreement. Such, equipment and materials shall
                  be delivered by ANSYS to RDS upon the expiration or
                  termination of this Agreement.


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         3.4      Reagents. RDS shall supply ANSYS with the reagents necessary
                  to manufacture the No-Step Kit.

         3.5      Price. (a) The parties shall negotiate in good faith pricing
                  for the No-Step Kits. Within a reasonable time from the
                  execution date of this Agreement, but in no event later than
                  one hundred and twenty (120) days prior to the scheduled date
                  of the product launch by RDS of the No-Step Kits, the parties
                  shall finalize the pricing for such kits and attach a copy
                  hereto as Exhibit B. In the event that the parties are unable
                  to reach an agreement on pricing within this 120 day time
                  frame, either party may terminate the Agreement.

         3.6      Exclusivity. ANSYS shall manufacture the No-Step Kits at its
                  facilities in Irvine California and shall supply such products
                  to RDS on an exclusive basis, even as to ANSYS, worldwide;
                  provided however, that in the event ANSYS receives a license
                  under Article 6, ANSYS may manufacture and supply the No-Step
                  Kits in those markets or market segments covered by such
                  license.

         3.7      Packaging. ANSYS shall label the No-Step Kit with language to
                  be supplied by RDS and shall package the product with a
                  package insert, the language of which shall also be supplied
                  by RDS. RDS shall have the right, in its sole discretion, to
                  make changes to the label, package insert and other labeling
                  for the No-Step Kits, which changes shall be submitted by RDS
                  to the applicable governmental authorities, if required.
                  ANSYS's name may, at RDS's sole discretion, appear on the
                  label, package insert and other labeling for the No-Step Kits.

         3.8      Quality Control and Assurance. (a) ANSYS shall manufacture the
                  No-Step Kits in accordance with the then current product
                  specifications as set forth on Exhibit A, as well as with the
                  then current quality control specifications, which, at RDS's
                  sole discretion, it may modify from time to time. A copy of
                  the quality control specifications will be provided by RDS
                  within a reasonable period after execution of this Agreement
                  and shall be attached hereto as Exhibit C.

                           (b) ANSYS shall manufacture the NO-Step Kits so that
                  they comply with all federal, state and local laws and
                  regulations.

                           (c) ANSYS shall perform quality control and quality
                  assurance testing and verification to ensure that the No-Step
                  Kits comply with the requirements set forth in Sections 3.8(a)
                  and (b).

                           (d) Each time ANSYS ships the No-Step Kits to RDS,
                  ANSYS shall provide RDS with a Certificate of Analysis at the
                  time of shipment, certifying that the products have been
                  evaluated by ANSYS's Quality Control and Quality Assurance
                  departments and that the product complies with the
                  requirements set forth in Sections 3.8(a) and (b). Within a
                  reasonable period after execution of this Agreement RDS shall
                  provide ANSYS with a sample Certificate of Analysis which
                  ANSYS shall use pursuant to this Section.


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4.0      ORDERS, DELIVERY, INVOICING AND PAYMENT

         4.1      Forecasts. Within a reasonable time from the date of this
                  Agreement, but in no event later than sixty (60) days prior to
                  the scheduled date of the product launch by RDS of the No-Step
                  Kit, RDS shall supply ANSYS with its current estimates for the
                  No-Step Kits for each of the four (4) three-calendar-month
                  periods following the product launch date. Each such estimate
                  for four (4) three-calendar-months periods hereinafter is
                  called a "Rolling Forecast." RDS shall thereafter provide
                  ANSYS with Rolling Forecasts on a quarterly basis. No minimum
                  units for any three-calendar-month period of any Rolling
                  Forecast are required to be forecasted by RDS; provided
                  however, that the quantity of No-Step Kits for the initial
                  three-calendar month period of any Rolling Forecast may,
                  without the consent of ANSYS, vary upward or downward from
                  RDS's prior estimate for such three calendar month period by
                  an amount not to exceed twenty percent (20%). RDS and ANSYS
                  shall be bound by RDS's estimates, if any, for the first
                  three-calendar month period of each such Rolling Forecast.
                  ANSYS's obligations to manufacture the No-Step Kits for RDS
                  under this Agreement shall be subject to its maximum
                  production capacity.

         4.2      Orders. RDS will order products by providing ANSYS with
                  written Purchase Orders, which shall contain the purchase
                  order number, product numbers, names and quantities, unit and
                  total purchase price and shipping instructions. No additional
                  terms or conditions shall be permitted to be added by ANSYS to
                  any Purchase order, whether by way of altering same or
                  providing a document that purports to contain additional
                  terms, and any such additional terms and conditions shall be
                  void and of no force or effect, notwithstanding that RDS may
                  accept and perform its obligations hereunder with respect to
                  any such allegedly modified Purchase Order without rejecting
                  specifically such additional terms and conditions.

         4.3      Shipments. ANSYS shall ship and deliver the No-Step Kits
                  F.O.B. ANSYS's shipping point to such RDS locations as
                  requested by RDS. RDS may select the freight carrier used by
                  ANSYS to ship the products and may monitor ANSYS's
                  shipping/freight practices as they pertain to this Agreement.
                  ANSYS shall ship the No-Step Kits within thirty (30) days of
                  receipt of a Purchase Order from RDS.

         4.4      Invoices and Payment. ANSYS shall submit to RDS, with each
                  shipment of the No-Step Kits, an invoice covering such
                  shipment. Each such invoice shall identify the RDS Purchase
                  Order number, product numbers, names and quantities, unit
                  price, freight charges and total amount to be remitted by RDS.
                  RDS shall pay for all such invoices within thirty (30) days
                  after its receipt of such invoices.


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         4.5      Lot Numbering/Expiration Dates. ANSYS shall make arrangements
                  for and implement the imprinting of lot numbers and expiration
                  dates for each No-Step Kit shipped. Such lot numbers and
                  expiration dates shall be affixed on the product and on the
                  shipping carton of each product as is required under good
                  commercial practice.


5.0      COOPERATION

         5.1      Technical Support. ANSYS shall provide reasonable technical
                  support and training relating to the No-Step Kits to RDS as
                  requested by RDS.

         5.2      Records and Accounting by ANSYS. ANSYS shall keep records of
                  the manufacture, testing and shipping of the products supplied
                  hereunder by ANSYS, and retain samples of such products that
                  are necessary to assist with, and support, good manufacturing
                  practices, product complaints, investigations and other
                  regulatory requirements. Such records and samples shall be
                  made available to RDS upon its request, and shall be retained
                  by ANSYS and be available to RDS for a period of three (3)
                  years following termination of this Agreement, or longer if
                  required by law.

         5.3      Product Recalls. ANSYS and RDS shall each maintain records as
                  may be necessary to permit a recall or a field correction of
                  any No-Step Kit delivered to RDS or customers of RDS, effected
                  voluntarily or under a threat of, or a directive by, any
                  governmental agency. Each party shall give immediate notice by
                  telephone (to be confirmed in writing) to the General Counsel
                  of the other party upon discovery that any No-Step Kit should
                  be recalled or corrected, or may be required to be recalled or
                  corrected, and, each party upon receiving any such notice or
                  upon any such discovery, shall cease and desist from further
                  shipments of No-Step Kits in its possession or control until a
                  decision has been made whether a recall or some other
                  corrective action is necessary. The decision to initiate a
                  recall or to take some other corrective action shall be made
                  by RDS after conferring with ANSYS. Each party shall cooperate
                  with the other in developing any necessary recall plan, and
                  the manner and extent of such plan shall be subject to prior
                  consultation, which consultation shall not delay such plan by
                  more than forty-eight (48) hours from the time of initial
                  notice. Any such recall or corrective action shall be made at
                  ANSYS's cost and expense if, and to the extent that, such
                  recall or corrective action results from, or arises out of,
                  any breach by ANSYS of its warranties or covenants hereunder.

         5.4      Product Returns. RDS shall have the responsibility for
                  handling customer returns of the No-Step Kits. ANSYS shall
                  provide RDS with such assistance as RDS may need to handle
                  such returns. Any such return shall be made at ANSYS's cost
                  and expense if, and to the extent that, such return results
                  from, or arises out of, any breach by ANSYS of its warranties
                  or covenants hereunder.


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         5.5      Governmental Agencies. Each party may communicate with any
                  Governmental agency, including but not limited to the United
                  States Food and Drug Administration, regarding the No-Step
                  Kits if in the opinion of that party's counsel, such
                  communication is necessary to comply with the terms of this
                  Agreement or the requirements of any law, governmental order
                  or regulation; provided however, that unless in the reasonable
                  opinion of its counsel there is a legal prohibition against
                  doing so, such party shall permit the other party to accompany
                  and take part in any communications with the agency, and to
                  receive copies of all such communications from the agency.

         5.6      Customer Questions And Complaints. (a) RDS shall have the
                  responsibility for responding to questions and complaints
                  regarding the No-Step Kits. Questions or complaints received
                  by ANSYS shall be promptly referred to RDS. RDS shall provide
                  ANSYS with reports summarizing such complaints and customer
                  questions, as requested by ANSYS, but in no event shall RDS
                  have to provide such reports more frequently than on a
                  quarterly basis.

                           (b) Within a reasonable time from the date of this
                  Agreement, but in no event later than the sixty (60) days
                  prior to the scheduled date of the product launch by RDS of
                  the No-Step Kit, ANSYS shall provide RDS with all necessary
                  information that will enable RDS to respond properly and
                  promptly to questions or complaints relating to the No-Step
                  Kits. ANSYS shall use its best efforts to keep such
                  information current.

                           (c) ANSYS shall provide RDS with such other
                  assistance as RDS may need to investigate and respond to
                  customer questions or complaints.

         5.7      Product Modifications. (a) ANSYS shall only make alterations,
                  modifications or improvements to the product specifications or
                  performance characteristics for the No-Step Kits supplied by
                  ANSYS to RDS under this Agreement if (i) prior written
                  approval is given by RDS, and (ii) new pricing for the No-Step
                  Kits, if necessary because such alteration, modification or
                  improvement changes the cost to manufacture the kits, is
                  agreed upon by the parties.

6.0      LICENSE

         6.1      RDS shall offer in writing to license the No-Step Kit to ANSYS
                  in those markets or market segments that RDS has determined it
                  will not sell the product.

         6.2      (a) In the event that RDS offers in writing to license the
                  No-Step Kit to ANSYS pursuant to Section 6.1, ANSYS shall have
                  ninety (90) days from the receipt of such written offer to
                  inform RDS in writing that it desires to obtain such a license


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                  from RDS. Thereafter, the parties agree to negotiate in good
                  faith a licensing agreement that shall include a licensing fee
                  not to exceed three percent (3%) of net sales of the product.
                  Agreement by the parties on all the terms of the licensing
                  agreement shall be a precondition before any such license can
                  become effective.

                           (b) In the event that ANSYS does not notify RDS
                  within the 90 day period set forth in Section 6.2(a) informing
                  RDS that it desires to obtain the license offered by RDS, then
                  RDS shall be free to offer such license to third parties
                  without any further obligations to ANSYS.

         6.3      ANSYS expressly acknowledges and agrees that in the event that
                  it receives a license from RDS to the No-Step Kit under this
                  Article 6 it shall have no right to sublicense, assign or
                  otherwise transfer its rights under such license, without
                  prior written approval of RDS.

         6.4      The terms and conditions of this Article 6 shall survive
                  termination or expiration of this Agreement and shall extend
                  until all of RDS's patent rights in No-step Kit expire.

7.0      TERM, RENEWAL AND TERMINATION

         7.1      Term. This Agreement, effective as of April 1, 1993, shall end
                  on December 31, 1999 unless terminated by one of the parties
                  in accordance with this Agreement.

         7.2      Renewal. RDS shall have the option, in its sole discretion, to
                  extend this Agreement for additional three (3) year terms, or
                  a portion thereof, upon written notice, subject to the same
                  terms and conditions of this Agreement. In the event that RDS
                  renews this Agreement, the parties agree to negotiate in good
                  faith a mutually acceptable price for the No-Step Kits. In the
                  event that the parties fail to agree upon new prices, the
                  pricing structure as set forth in Exhibit B shall remain
                  effective.

         7.3      Non-Renewal. In the event that RDS elects not to renew this
                  Agreement pursuant to Section 7.2, and provided that ANSYS is
                  not in breach of the Agreement, then and only then RDS shall
                  pay ANSYS a fee, to be negotiated in good faith by the
                  parties, for each No-Step Kit sold by RDS after the expiration
                  of this Agreement. Such fee shall not exceed three percent
                  (3%) of net sales of the No-Step Kits. RDS shall have no
                  obligation to pay ANSYS such fee in the event that the
                  Agreement is terminated by either party under Section 7.4.

         7.4      Termination. (a) Upon failure of either party to remedy its
                  breach of any of the obligations or provisions of this
                  Agreement within thirty (30) days following receipt of written
                  notice of said breach, the aggrieved party shall have the
                  right to 


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                  terminate this Agreement immediately by written notice;
                  provided however, that if the breach is due to a product
                  failure or defect in the No-Step Kit and the parties agree
                  that the actions needed to cure such problem requires more
                  than 30 days, then the cure period may be extended, upon
                  mutual agreement of the parties, for a reasonable period of
                  time.

                           (b) Either party at its sole option may immediately
                  terminate this Agreement upon written notice, but without
                  prior advance notice, to the other party in the event that (i)
                  the other party is declared insolvent or bankrupt by a court
                  of competent jurisdiction; (ii) a voluntary petition of
                  bankruptcy is filed in any court of competent jurisdiction by
                  such other party; or (iii) this Agreement is assigned by such
                  other party for the benefit of creditors.

                           (c) RDS may terminate this Agreement upon thirty (30)
                  days' written notice in the event that the Food Drug
                  Administration takes any action, or raises any objection, that
                  prevents RDS from importing, exporting, purchasing or selling
                  the No-Step Kits to customers.

                           (d) Any termination or expiration of this Agreement
                  shall not affect any outstanding obligations or payments due
                  hereunder prior to such termination or expiration, nor shall
                  it prejudice any other remedies that the parties may have
                  under this Agreement.

8.0      REPRESENTATIONS AND WARRANTIES

         8.1      Product Specifications. ANSYS represents and warrants that the
                  No-Step Kits shall comply with the then current product
                  specifications and then current quality control specifications
                  and with all federal, state and local laws and regulations.

         8.2      Good Manufacturing Practices. ANSYS represents and warrants
                  that the No-step Kits shall comply with and will be
                  manufactured in accordance with all applicable Good
                  Manufacturing Practices ("GMPs").

         8.3      Warranty of Purpose. ANSYS represents and warrants that the
                  No-Step Kits supplied under this Agreement are suitable and
                  may be used for the purposes for which RDS is selling such
                  kits.

         8.4      Product Defects. ANSYS represents and warrants that the
                  No-Step Kits supplied under this Agreement are free from all
                  defects and that the work performed by ANSYS under this
                  Agreement is of recognized standard quality or better.

         8.5      Product Development. ANSYS represents and warrants that the
                  No-Step Kits will be manufactured by ANSYS, or by third
                  parties for ANSYS free and clear of any claims by such third
                  parties.


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         8.6      Authority. Each party represents and warrants to the other
                  party that it has the full right and authority to enter into
                  this Agreement, and that it is not aware of any impediment
                  that would inhibit its ability to perform its obligations
                  hereunder.

         8.7      Consequential Damages. In the event of a breach of any
                  representation or warranty, express or implied, in addition to
                  other rights RDS may have, it may withhold payment and/or
                  cause such breach to be corrected and charge ANSYS; therefore
                  ANSYS shall be liable for all consequential damages. Except as
                  specifically provided herein, ANSYS makes no other
                  representations or warranties express or implied.

9.0      INDEMNITY

         9.1      (a) RDS agrees to defend, indemnify and hold ANSYS, its
                  officers, directors, employees and agents harmless against any
                  and all losses, damages, costs, claims, demands, judgments and
                  liability resulting from, or relating to RDS's performance
                  under this Agreement, except to the extent that any such
                  losses, damages, costs, demands, costs, claims, judgments and
                  liability are due to the negligence or wrongful act(s) of
                  ANSYS, its employees or agents.

                           (b) If by reason of manufacturing or selling the
                  No-Step Kit to RDS under this Agreement ANSYS is sued or
                  threatened with suit for alleged patent infringement covering
                  (i) the No-Step Kit, or (ii) the process for producing the
                  No-Step Kit, RDS shall, at its own expense, defend such suit
                  and indemnify ANSYS against all losses and expenses incurred
                  in connection with such suit or threatened suit including
                  judgments, decrees, court costs and attorney fees, except to
                  the extent that the claim relates to, or results from ANSYS's
                  noncompliance with the terms of this Agreement.

         9.2      ANSYS agrees to defend, indemnify and hold RDS, its officers,
                  directors, employees and agents harmless against any and all
                  losses, damages, costs, claims, demands, judgments and
                  liability resulting from, or relating to ANSYS's performance
                  under this Agreement, except to the extent that any such
                  losses, damages, costs, demands, costs, claims, judgments and
                  liability are due to (i) the negligence or wrongful act(s) of
                  RDS, its employees or agents, or (ii) patent infringement
                  suits or threatened suits that, pursuant to Section 9.1(b),
                  RDS has agreed to defend and provide indemnification to ANSYS.

10.0     CONFIDENTIALITY

         10.1     During and in furtherance this Agreement, each party may
                  disclose certain of its Confidential Information to the other
                  party.


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         10.2     During the Term of this Agreement, and for a period of five
                  (5) years from the termination thereof, RDS and ANSYS each
                  agree (i) to use the Confidential Information only in
                  connection with the terms of this Agreement, (ii) to treat the
                  Confidential Information as it would its own proprietary
                  information, and (iii) to take all reasonable precautions to
                  prevent the disclosure of the Confidential Information to any
                  third party, other than an Affiliate, without the prior
                  written consent of the other party.

         10.3     A party shall be relieved of any and all of the obligations
                  under Section 10.2 regarding Confidential Information which
                  (i) was known to the party receiving the Confidential
                  Information (the "receiving Party") prior to receipt
                  hereunder, (ii) at the time of disclosure to by the disclosing
                  party to the Receiving Party, was generally available to the
                  public, or which after disclosure hereunder becomes generally
                  available to the public through no fault attributable to the
                  Receiving Party; or (iii) is hereafter made available to the
                  Receiving Party for use or disclosure by the Receiving Party
                  from any third party having a right to do so.

11.0     MISCELLANEOUS

         11.1     Independent Contractors. The parties shall be deemed to be
                  independent contractors, and this Agreement shall not be
                  construed to create between ANSYS and RDS any other
                  relationship such as, by way of example only, that of
                  employer-employee, principal agent, joint-venturer, copartners
                  or any similar relationship, the existence of which is
                  expressly denied by the parties hereto.

         11.2     Inspection. RDS may inspect ANSYS reports and records relating
                  to the performance under this Agreement during normal business
                  hours and with reasonable advance notice.

         11.3     Access. ANSYS shall provide RDS access to any of its
                  facilities, during normal business hours and with reasonable
                  advance notice, in which the No-Step Kits are manufactured,
                  stored, handled, shipped or used in order to permit RDS
                  verification of ANSYS's compliance with this Agreement and
                  applicable laws.

         11.4     Insurance. ANSYS shall maintain liability and other insurance
                  coverage satisfactory to RDS, during the term of this
                  Agreement and for five (5) years thereafter, which insurance
                  shall name RDS as an additional insured. Such insurance shall
                  include comprehensive general, liability contractual
                  liability, and product liability and have limits no less than
                  $2,000,000.00 per occurrence. ANSYS shall provide to RDS a
                  Certificate of Insurance evidencing such coverage and shall
                  provide RDS with notice of any change or modification thereto.

         11.5     Taxes. ANSYS shall be liable for any and all local, state and
                  federal taxes and license fees, arising out of the sale of
                  No-Step Kits to RDS pursuant to this Agreement.


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         11.6     New Drugs of Abuse Products. (a) RDS shall have the right of
                  first refusal to market exclusively any and all new
                  immunoassay drugs of abuse products developed by ANSYS.

                           (b) In the event that ANSYS manufactures or develops
                  such a product, ANSYS shall so immediately, notify RDS in
                  writing and shall provide RDS with sufficient information,
                  data, and samples, for RDS to evaluate the product and
                  determine its interest, if any, in the product. RDS shall have
                  ninety (90) days from receipt of such information, data and
                  samples to evaluate the product and if interested shall notify
                  ANSYS in, writing within ten (10) business days of the
                  conclusion, of this evaluation period.

                           (c) In the event that RDS expresses such an interest,
                  the parties shall negotiate in good faith to enter into an
                  exclusive marketing agreement upon terms and conditions that
                  are commercially reasonable. In the event that the parties
                  fail to reach a negotiated agreement within seventy (70) days
                  from RDS's completion of the evaluation, ANSYS may then offer
                  such product to other potential companies, provided that such
                  offer shall not be more favorable to such company than
                  previously offered to RDS.

         11.7     Choice of Law. This Agreement shall be construed under, and
                  the rights of the parties hereto shall be governed by the laws
                  of the state of New Jersey, without giving effect to New
                  Jersey's choice of law principles. The parties agree that the
                  Superior Court of New Jersey and the United States District
                  Court for the District of New Jersey shall have exclusive
                  jurisdiction to hear and determine any and all disputes
                  pertaining directly or indirectly to this Agreement. The
                  parties expressly consent to venue and to the exercise of
                  personal jurisdiction by the aforesaid courts. Additionally,
                  each party expressly waives any and all right to commence and
                  maintain any lawsuit against the other party, whether at law
                  or in equity, in any other court or jurisdiction.

         11.8     Disputes. In the event of any law suit between ANSYS and RDS
                  in connection with this Agreement, the unsuccessful party
                  shall pay to the prevailing party all costs and expenses,
                  including reasonable attorneys' fees, incurred in such action
                  or proceeding and in any appeal in connection therewith by
                  such prevailing party, and any such costs, expenses and
                  reasonable attorneys' fees shall be included as a part of any
                  such judgment entered in favor of such prevailing party.

         11.9     Other Products. Nothing in the Agreement shall be, construed
                  to prevent or limit either party from selling any of its other
                  products in any market.

         11.10    No Waiver. Either party's failure to require the other party
                  to comply with any provision of this Agreement shall not be
                  deemed a waiver of such provision or any other provision of
                  this Agreement.


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         11.11    Severability. In the event that one or more of the provisions
                  of this Agreement shall, for any reason, be held to be
                  invalid, illegal or unenforceable in any respect, such
                  invalidity, illegality or unenforceability shall not affect
                  any of the other provisions of this Agreement, but this
                  Agreement shall be construed as if such invalid, illegal or
                  unenforceable provision or provisions had never been contained
                  herein.

         11.12    Assignment. This Agreement shall not be assignable nor its
                  rights hereunder transferred in any way by either party hereto
                  other than to an Affiliate, except with the written consent of
                  the other party, which consent shall not be unreasonable
                  withheld.

         11.13    Binding Effect. This Agreement shall bind and inure to the
                  benefit of the parties hereto and their respective successors
                  and permitted assigns.

         11.14    Force Majeure. Neither party shall be liable for the failure
                  to perform its obligations under this Agreement if such
                  failure is occasioned by a contingency beyond such party's
                  reasonable control, including, but not limited to, strikes or
                  other labor disturbances, lockouts, riots, wars, fires, floods
                  or storms. A party claiming a right to excused performance
                  under this Section shall immediately notify the other party
                  writing of the extent of its inability to perform, which
                  notice shall specify the occurrence beyond its reasonable
                  control that prevents such performance.

         11.15    Notices. Any notice, or other written communication, required
                  or permitted hereunder shall be sufficiently made or given to
                  the other party by personal in-ha delivery, by telecopier
                  communication or by sending t same by first class mail,
                  postage prepaid to the mail address, or telecopier numbers set
                  forth below:


                            If to RDS:

                                     Roche Diagnostic Systems, Inc.
                                     1080 Highway 202
                                     Branchburg, New Jersey 08876-1760
                                     Attention: Vice President, International
                                     Drug Monitoring Business Unit

                                     Telecopier No: (908) 253-7645

                            with a copy to

                                     Jordan D. Cooper, Esq.
                                     Roche Diagnostics Systems, Inc.
                                     340 Kingsland Street
                                     Nutley, N.J..07110

                                     Telecopier No: (201) 235-3500


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                            If to ANSYS:

                                     ANSYS, Inc.
                                     2 Goodyear
                                     Irvine, California 92718
                                     Attention: President

                                     Telecopier (714) 768-0311

                  or to such other addresses or telecopier numbers provided to
                  the other party in accordance with the terms of this Section.
                  Notices or written communications made or given by personal
                  in-hand delivery or by telecopier shall be deemed to have been
                  sufficiently made or given when sent, or if mailed, three (3)
                  days after being deposited in the United States Mail, postage
                  prepaid or upon receipt, whichever is sooner.

         11.16    Entire Agreement. This Agreement constitutes the full,
                  complete, final and integrated agreement between the parties
                  hereto relating to the subject matter hereof and supersedes
                  all previous written or oral negotiations, commitments,
                  agreements, transactions or understandings with respect to the
                  subject matter hereof. Except for Exhibit A (Product
                  Specifications) and Exhibit C (Quality Control Specifications)
                  which RDS may modify, at its sole option, from time to time,
                  any modification, amendment or supplement to this Agreement
                  must be in writing and signed by authorized representatives of
                  both parties.

         11.17    Headings. The titles and headings herein are for convenience
                  only and shall not be used to interpret or construe the terms
                  and conditions of this Agreement.

         11.18    Singular Terms. Except as otherwise expressly provided herein
                  or unless the context otherwise requires, all references to
                  the singular shall include the plural as well.

         11.19    Execution in Counterparts. This Agreement may be executed in
                  two (2) counterparts, each of which shall be deemed an
                  original, but all of which together shal1 constitute one and
                  the same instrument.


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         IN WITNESS WHEREOF, the duly authorized representatives of the parties
have executed this Agreement as of the dates set forth below.

ANSYS, INC.                                 ROCHE DIAGNOSTIC SYSTEMS, INC.
By:  /s/ C. Michael O'Donnell, Ph.D         By: /s/ Adrienne Choma
Name: ___________________________           Name: __________________________
Title: __________________________           Title: Vice President
Date: ___________________________           Date:  7/26/93

                                    EXHIBIT A
                           PRODUCT SPECIFICATION SHEET
                              ONTRAK GENERATION II


July 1993

I.       PRODUCT DESCRIPTION
         ONTRAK Generation II for the on-site testing market meeting the
         following general requirements:

         *        No step assay with no reagent addition or urine handling
         *        Clear endpoint interpretation by non-technical operator
         *        Multi-drug format to accommodate three to five analytes

II.      PERFORMANCE

         1.       Clinical Claims - Qualitative detection of abused drug or drug
                  metabolite at specified cut-off level.
         2.       Linearity - Standard curve should be as steep as possible at
                  cut-off.
         3.       Accuracy and Precision - [***]
         4.       Sensitivity - Comparable to ONTRAK at cut-off.
         5.       Specificity - Comparable to ONTRAK.
         6.       Interference's - Comparable to ONTRAK.
         7.       Cross Reactivities - Comparable to ONTRAK.
         8.       Stability - [***]
         9.       Storage Conditions - RT storage with shipment at ambient
                  temperature via ground transportation. Container with sample
                  may be stored refrigerated.
         10.      Controls - Positive and negative controls specimens
                  commercially available with test incorporating a "test
                  complete" indication.
         11.      Cut-off - Consistent with NIDA Guidelines or as established.

III.     PROCEDURE 1. Sample Type - Urine 2. Sample Volume - :5 250 /uL.
         3.       Reagent Volume - Preloaded dose.
         4.       Number of Off-Line Steps - Zero.
         5.       Analysis Time - Approximately 3 minutes, no timing steps.
         6.       Analysis Temperature - 2-450C.

[***]   Confidential treatment has been requested for the redacted portions. The
        confidential redacted portion has been omitted and filed separately with
        the Securities and Exchange Commission.


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IV.      PRODUCT EMBODIMENT

         1.       No urine handling.
         2.       Test embodied in specimen container requiring no specimen or
                  reagent handling and guards against potential contact or
                  splashing on operator by contact with lid or cup.
         3.       Test cannot be inadvertently run, read or adulterated by
                  client.
         4.       Positive/Negative and Test Complete read required as part of
                  mold.
         5.       Test with specimen must with shippable, leak-proof,
                  identifiable and allow for recovery of specimen for
                  confirmation testing.
         6.       Test must comply with chain of custody requirements.
         7.       Test must be able to be stored stacked.
         8.       Assembly of test must be automatable/manufacturable with
                  capacity to manufacture 100,000 tests per week.
         9.       No sample overload or constriction of flow tolerable.
         10.      Test cannot be compatible with generic specimen containers or
                  lids.
         11.      Proprietary configuration to discourage competitive offerings.
         12.      Test results should be able to be photocopied.
         13.      QC testing of random sampling aggressive enough to assure
                  product integrity with respect to physical and performance
                  characteristics. These cycles should be agreed upon mutually
                  by TLIw and RIDS and will diminish as assurance of quality
                  increases.

V. LABELING
         1.       Label must include information regarding client
                  identification, date, tester, and testers signature. (A lid
                  label may be incorporated to provide additional labeling
                  space.)
         2.       Each test must be color coded consistent with current ONTRAK
                  product and reflect the Roche identity and product codes and a
                  pictorial procedure guide.
         3.       Label must provide Positive/Negative and Test Complete
                  indication in a limited viewing area, consistent with mold.
         4.       Label to incorporate Positive/Negative identification "key".
         5.       A milliliters scale should be present to identify approximate
                  amount of specimen.
         6.       The capacity to add bar coding and a temperature strip should
                  be designed in the label.


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VI. PACKAGING
         1.       Number of test cups per kit to be defined. Kit to include
                  individually sealed test cups with drying agent and five
                  language package insert and any other supplies necessary to
                  perform the test.
         2.       Box to serve has outer shipping carton. 3. Kit components to
                  meet recycling requirements where possible.
         3.       Kit components to meet recycling requirements where possible.


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                                    EXHIBIT B

                            PRICING FOR NO-STEP KITS

PRICE TO ROCHE FOR FIRST FULL YEAR OF PRODUCTION:  $[***].

                  [***]

PRICE MAY BE ADJUSTED BY MUTUAL CONSENT AT ANY TIME



ANSYS, INC.                                   ROCHE DIAGNOSTIC SYSTEMS


/S/  STEPHEN K. SCHULTHEIS                    /S/  ADRIENNE CHOMA
President                                     Vice President
                                              International Drug Monitoring Unit


[***]   Confidential treatment has been requested for the redacted portions. The
        confidential redacted portion has been omitted and filed separately with
        the Securities and Exchange Commission.


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