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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                                                   EXHIBIT 10(a)

                              AMENDED AND RESTATED

                          PURCHASE AND SUPPLY AGREEMENT

         This Amended and Restated Purchase and Supply Agreement (the
"Agreement"), effective as of June 21, 2004 (the "Effective Date"), is made by
and between DUSA Pharmaceuticals, Inc., a New Jersey corporation, having offices
at 25 Upton Drive, Wilmington, Massachusetts 01887 ("DUSA"), and National
Biological Corporation, an Ohio corporation having offices at 1532 Enterprise
Parkway, Twinsburg, OH 44087 ("NBC").

                                   BACKGROUND

         WHEREAS, DUSA and NBC entered into a certain Purchase and Supply
Agreement on November 5, 1998, pursuant to which DUSA purchases units of the
Light Source (defined below) and NBC manufactures and supplies units of the
Light Source (the "Original Purchase and Supply Agreement"); and

         WHEREAS, the parties recognize that the Original Purchase and Supply
Agreement does not meet the needs of the parties and the parties wish to
continue their relationship under this Amended and Restated Purchase and Supply
Agreement, all as set forth herein below.

         NOW THEREFORE, for and in consideration of the covenants, conditions,
and undertakings hereinafter set forth, it is agreed by and between the parties
as follows:

                                    ARTICLE 1
                                   DEFINITIONS

         1.1 "BLU-U(R) Trademark" shall mean the "BLU-U" trademark that DUSA has
registered in connection with the Light Source, or such other trademark that
DUSA registers for use with the Light Source in jurisdictions in which "BLU-U"
is not selected by DUSA for use.

         1.2 "Confidential Information" shall have the meaning as set forth in
Section 9.1 below.

         1.3 "DUSA Technology" shall mean DUSA Patents and DUSA Technical
Information.

                  1.3.1 "DUSA Technical Information" shall mean [C.I.],
including, but not limited to: [C.I.]; in each case that is possessed by DUSA as
of the Effective Date or [C.I.] during the term of this Agreement, to the extent
such relates to the [C.I.] of the Light Source and to the extent that DUSA owns
or controls the same.

                  1.3.2 "DUSA Patents" shall mean all patents and all reissues,
renewals, re-examinations and extensions thereof, and patent applications
therefor, and any divisions or continuations, in whole or in part, thereof,
which claim the [C.I.] and that are owned or controlled by DUSA during the term
of this Agreement.

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that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

         1.4 "FDA" shall mean the United States Food and Drug Administration.

         1.5 "Force Majeure Event" shall have the meaning as set forth in
Section 12.3 below.

         1.6 "HPPB" shall mean the Canadian Health Products and Protection
Branch.

         1.7 "Light Source" shall mean DUSA's 4170 BLU-U(R) meeting the then
current Specifications therefor together with the Stand.

         1.8 "NBC Technology" shall mean NBC Patents and NBC Technical
Information.

                  1.8.1 "NBC Technical Information" shall mean [C.I.],
including, but not limited to: [C.I.]; in each case that is possessed by NBC as
of the Effective Date or [C.I.] during the term of this Agreement, to the extent
such relates to the [C.I.] of the Light Source and to the extent that NBC owns
or controls the same. For the avoidance of doubt, NBC Technology relates to the
[C.I.].

                  1.8.2 "NBC Patents" shall mean all patents and all reissues,
renewals, re-examinations and extensions thereof, and patent applications
therefor, and any divisions or continuations, in whole or in part, thereof,
which claim [C.I.] and that are owned or controlled by NBC during the term of
this Agreement.

         1.9 "Output Regulating Circuitry System" shall mean, collectively and
individually, the [C.I.] of a Light Source.

         1.10 "Plastic Housing" shall mean that portion of the outer plastic
covering of the Light Source designed by DUSA.

         1.11 "QS" shall mean current Quality Systems regulations, including
without limitation 21 CFR Part 820, et. seq., policies and guidance documents
promulgated by the FDA for the design, manufacture, processing or packaging of
medical devices, ISO 13485 Medical Devices - Quality Management Systems -
Requirements for Regulatory Purposes, and corresponding regulatory standards and
regulations required by other applicable regulatory agencies. QS shall also
include those Quality Systems requirements specified by DUSA in the
Specifications.

         1.12 "Specifications" shall mean the specifications set forth in
Exhibit A-1, as may be modified in accordance with Section 3.6 below.

         1.13 "Stand" shall mean the stand for the Light Source meeting the then
current Specifications therefor, which Specifications are agreed to and updated
by the parties hereto.

         1.14 "U-Type Bulb" shall mean a U-shaped fluorescent bulb described on
Drawing No. 8BU-417 set forth in Exhibit A-2, that meets or is similar to the
Specifications.

         1.15 "UBL Trademark" shall mean the "UBL" and "NBC-UBL" trademarks that
NBC uses in connection with its products.

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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                    ARTICLE 2
                                     SUPPLY

         2.1 Light Source Supply. Subject to the terms and conditions of this
Agreement, NBC shall supply to DUSA quantities of the Light Source ordered by
DUSA from time to time during the term of this Agreement on a purchase order
basis. The parties recognize and acknowledge that DUSA's business is currently
dependent on the supply of the Light Source to DUSA by NBC as specified
hereunder.

         2.2 Orders.

                  2.2.1 Orders. DUSA shall place orders with NBC for delivery of
a quantity of Light Source units on written notice [C.I.] prior to the requested
delivery date. NBC shall accept such orders from DUSA, subject to the remaining
terms and conditions of this Agreement.

                  2.2.2 Form of Orders. DUSA's orders shall be made pursuant to
a written purchase order which is in the form attached hereto as Exhibit B, and
shall provide for shipment in accordance with the delivery dates set forth in
the purchase orders. At all times during this Agreement, NBC shall use its
reasonable best efforts to meet the monthly delivery dates set forth in each
purchase order. Notwithstanding the foregoing language, NBC shall ship Light
Source units in inventory as requested pursuant to Section 2.5 below. Any change
to a purchase order may be made by the issuance of a written amended change
order by both parties. ANY ADDITIONAL OR INCONSISTENT TERMS OR CONDITIONS OF ANY
PURCHASE ORDER, ACKNOWLEDGMENTS OR SIMILAR STANDARDIZED FORMS GIVEN OR RECEIVED
PURSUANT TO THIS AGREEMENT SHALL HAVE NO EFFECT AND SUCH TERMS AND CONDITIONS
ARE HEREBY EXCLUDED UNLESS SPECIFICALLY AGREED OTHERWISE BY A WRITING SIGNED BY
BOTH PARTIES PURSUANT TO SECTION 12.12.

                  2.2.3 Delays. DUSA shall be entitled to reschedule deliveries
of the Light Source ordered hereunder, for [C.I.] provided that DUSA notifies
NBC of such desired changes, in writing, at least [C.I.] prior to the scheduled
delivery date. Without limiting the foregoing, if such delay is greater than
[C.I.], NBC may invoice DUSA for the Light Source so delayed and DUSA will
[C.I.] to such Light Source [C.I.]; in which case NBC agrees to: (i) maintain a
written record identifying such Light Source as [C.I.], (ii) maintain such Light
Source [C.I.], and (iii) [C.I.]. Furthermore, if such rescheduling represents a
delay in shipment of more than [C.I.] from the original delivery date, DUSA
shall [C.I.] on such delayed Light Source during such extended period and
[C.I.]. For avoidance of doubt, the preceding provisions of this Section 2.2.3
shall not in anyway limit DUSA's rights of inspection and rejection set forth in
Section 3.3 below.

         2.3 Compensation; Quote and Price.

                  2.3.1 Compensation. In consideration for [C.I.] to the
Original Purchase and Supply Agreement contained in this Agreement, DUSA shall
pay to NBC upon execution of this Agreement by both parties One Hundred Ten
Thousand Dollars ($110,000.00).

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that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                  2.3.2 Quote and Price. The price to be paid by DUSA per Light
Source unit ordered by DUSA during the next [C.I.] shall be set forth in Exhibit
C hereto. NBC agrees to provide to DUSA quotes for [C.I.] of the Light Source on
a per [C.I.] no later than the Effective Date of this Agreement.

         2.4 Packaging. Units of Light Source shall be packaged in containers
and labeled in accordance with the Specifications.

         2.5 Delivery. NBC shall deliver quantities of Light Source units
ordered by DUSA on the dates specified in DUSA's purchase orders submitted in
accordance with Section 2.2 above. All units of Light Source shall be delivered
[C.I.] to the location specified by DUSA prior to the shipping date therefor.
The carrier shall be selected by agreement between DUSA and NBC, provided that
in the event no such agreement is reached, DUSA shall select the carrier. Each
shipment shall be insured for the benefit of DUSA. So long as NBC receives
shipment notification by 3:00pm EST pursuant to a purchase order for Light
Source units in inventory, NBC shall ship the units of Light Source on the same
business day, or on the next business day for orders received after 3:00pm EST.

         2.6 Invoicing; Payment. Unless [C.I.] as set forth in Section 2.2.3 or
2.2.4 above, NBC shall submit an invoice to DUSA [C.I.] of the Light Source
ordered by DUSA hereunder. All invoices shall be sent to the address specified
in the purchase order or as otherwise instructed by DUSA in writing, and each
such invoice shall state the aggregate and unit Price for the Light Source in a
given shipment, [C.I.] to the purchase or shipment initially [C.I.]. All
payments hereunder shall be made in U.S. Dollars, by [C.I.]. Payment shall be
due to NBC within [C.I.] from the date of an invoice issued hereunder; provided
that payment made within [C.I.] of the foregoing shall be subject to a [C.I.].
Notwithstanding the foregoing, NBC shall invoice [C.I.] separately on a [C.I.]
and DUSA agrees to remit payment therefor [C.I.]. In addition, such shipping and
handling charges shall not be subject to [C.I.]. Any [C.I.] shall be subject to
interest at the [C.I.] per month or the highest rate allowable under applicable
law, on the number of days overdue.

                                    ARTICLE 3
                                     QUALITY

         3.1 Quality. Each Light Source supplied by NBC shall materially conform
with the current Specifications therefor and shall be manufactured in accordance
with all applicable QS manufacturing and record keeping procedures and
regulatory approvals of the FDA and/or HPPD for the Light Source at NBC's plant
located at 1532 Enterprise Parkway, Twinsburg, Ohio 44087 (the "Facility").
Notwithstanding anything herein to the contrary and for the avoidance of doubt,
all Specifications shall be deemed to be material.

         3.2 Quality Control. Prior to each shipment of the Light Source, NBC
shall perform quality control procedures, inspections and tests to verify that
the Light Source to be shipped conform materially with the Specifications. Each
shipment of components of the Light Source shall be accompanied by a certificate
of conformance describing all current requirements of the Specifications,
results of tests performed certifying that the Light Source supplied have been

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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

manufactured, controlled and released according to the Specifications and all
relevant QS requirements at the Facility stipulated under Section 3.1 above.
Without limiting the foregoing, if NBC's performance of the inspection and
applicable testing procedures described in Exhibit D requires [C.I.], then DUSA
agrees to either (i) [C.I.] or (ii) [C.I.]; provided that in either such case
the following shall apply: NBC shall hold such equipment at NBC's risk and shall
replace the same if they are lost, damaged or destroyed. NBC shall maintain such
equipment in good condition (subject to normal wear and tear); and such
equipment shall be subject to [C.I.] upon expiration or termination of this
Agreement. Accordingly, NBC agrees to cooperate with DUSA in the filing of any
UCC financing statements relating to such equipment as DUSA may deem necessary
or useful. In addition, NBC shall use such equipment solely for the testing and
inspection of Light Source units hereunder, unless otherwise agreed by DUSA.
Furthermore, NBC shall properly maintain tooling and test equipment whether
owned by DUSA or NBC during the Term of this Agreement and the Support Period.

         3.3 Acceptance/Returns.

                  3.3.1 General. Acceptance by DUSA of Light Source units
delivered by NBC hereunder shall be subject to inspection and applicable testing
as generally described in Exhibit D by DUSA or its designee. If on such
inspection DUSA or its designee discovers that any Light Source shipped
hereunder fails to materially conform with the Specifications or otherwise fails
to materially conform to the warranties given by NBC in Section 6.1 below, DUSA
or such designee may reject such Light Source, which rejection shall be
accomplished by giving written notice to NBC specifying the manner in which such
Light Source fails to meet the foregoing requirements and request a Return
Material Authorization ("RMA") from NBC. DUSA or its designee shall return the
nonconforming Light Source in accordance with NBC's reasonable instructions with
the RMA attached [C.I.]. Upon receipt of the nonconforming Light Source NBC
shall promptly issue to DUSA a credit for all amounts invoiced (including
shipping and handling charges) for such Light Source. NBC shall use its best
efforts to replace the Light Source returned by DUSA within the shortest
possible time. The replacement of nonconforming Light Source units shall have
priority over the supply of Light Source units ordered for shipment under
Section 2.2 prior to the return or any time after the return of the
nonconforming Light Source unit to NBC. The warranties given by NBC in Section
6.1 below shall survive any failure to reject by DUSA under this Section 3.3.

                  3.3.2 Settlement of Claims. In case of a disagreement between
the parties regarding whether a particular Light Source unit materially complies
with the Specifications, the claim shall be [C.I.] or [C.I.] mutually agreed
upon by the parties [C.I.], the appointment of which shall not be unreasonably
withheld or delayed by either party. The determination of [C.I.] with respect to
such dispute shall be final and binding upon the parties. The parties and the
[C.I.] shall use their best efforts to [C.I.] as set forth above. The fees and
expenses of the [C.I.] shall be paid [C.I.] is made.

                  3.3.3. Returns. In the event Light Sources or accessories such
as caster kits or safety goggles are returned to NBC by a customer of DUSA for
repair, NBC shall inspect and evaluate such returned goods for failure analysis
or customer complaints and report its findings

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

in writing to DUSA's Quality Assurance Department within [C.I.] of receipt by
NBC of such returned goods.

         3.4 Latent Defects. It is recognized that it is possible for a Light
Source to have defects which are not be discovered upon reasonable physical
inspection or testing ("Latent Defects"). As soon as either party becomes aware
of a Latent Defect in any Light Source it shall immediately notify the other
party as to the serial number(s) of the Light Source(s) involved, which at
DUSA's election, shall be deemed rejected as of the date of such notice. NBC
agrees to [C.I.] all Light Source(s) so involved [C.I.]. For purposes of this
Section 3.4, "defect" shall mean that a Light Source fails to conform to the
warranties given by NBC herein; however, "defect" for purposes of the foregoing,
shall [C.I.].

         3.5 Presence at Facility. Upon [C.I.] given by DUSA to NBC, DUSA shall
have the right to assign a reasonable number of employees or consultants of DUSA
to inspect and audit the Facility at which Light Source are manufactured in
order to verify NBC's compliance with QS and other agreed requirements,
provided, however that (i) such employees or consultants shall not unreasonably
interfere with other activities being carried out at the Facility, (ii) that
such employees or consultants shall observe all rules and regulations applicable
to visitors and to individuals employed at the Facility, and (iii) such
employees or consultants agree to maintain the Confidential Information of NBC
in accordance with Article 9 below.

         3.6 Changes. DUSA shall have the right to modify the Specifications
from time to time. All such modifications shall be in writing and shall be
signed by an authorized representative of DUSA and NBC, and shall be effective
for orders of applicable units placed after such notice. If such modifications
result in a material change in [C.I.] as shown by [C.I.], the parties shall
agree upon [C.I.] of the Light Source hereunder; and if such modifications
result in a delay in delivery, the parties shall negotiate a reasonable
extension of the affected lead times. NBC shall not make any changes in the
manufacturing process, materials or critical suppliers without the prior written
consent of DUSA which shall not be unreasonably withheld.

                                    ARTICLE 4
                                    LICENSES

         4.1 To NBC. DUSA hereby grants to NBC a [C.I.] license under the DUSA
Technology to manufacture the Light Source to the extent it is ordered by DUSA
hereunder and to deliver such Light Source to DUSA or its designee as specified
in this Agreement. The foregoing license shall be [C.I.] with the prior written
consent of DUSA. For the avoidance of doubt, there is no other license or right
whatsoever being granted to NBC by DUSA under DUSA Technology by the terms of
this Agreement.

         4.2 To DUSA. NBC hereby grants to DUSA an [C.I.] license under the NBC
Technology to import, make or have made, use, sell, have sold and otherwise
dispose of the Light Source, including without limitation, to purchase directly
from NBC's supplier for DUSA's use and benefit, and for resale or other
disposition, the U-Type Bulb, in the Light Source or any light device sold by
DUSA. NBC shall provide to DUSA or its designee copies of all documentation
within NBC's control that is reasonably necessary for DUSA to exercise the

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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

licenses granted hereunder, and shall reasonably cooperate with DUSA to
establish supply of Light Source, including sources of components and other
materials. In the event that DUSA has Light Source manufactured by a third
party, DUSA shall obtain from such third party a written confidentiality
agreement to protect against the unauthorized use and disclosure of NBC's
Confidential Information.

         4.3 NBC Retention of Rights. Nothing herein shall be interpreted to
limit or restrict NBC's rights to import, manufacture, sell or supply a U-Type
bulb or other bulbs, either alone or in conjunction with or incorporated in any
type of device provided that such device is not the Light Source and NBC does
not use the BLU-U(R) Trademark.

                                    ARTICLE 5
                               REGULATORY MATTERS

         5.1 Regulatory Approvals. The parties understand and agree that DUSA,
itself or through its agents, shall have the sole right to correspond with and
submit regulatory applications and other filings necessary for the sale of Light
Source to the FDA, HPPB or other foreign regulatory agencies to obtain approvals
to import, export, sell or otherwise commercialize the Light Source alone or
with other products (collectively, "Approvals") as DUSA deems useful or
necessary. Accordingly, except as otherwise required by law, NBC shall not
correspond directly with the FDA, HPPB or any other regulatory agency relating
to the process of obtaining Approvals or any obtained Approval for the Light
Source, without DUSA's prior written permission. Notwithstanding the foregoing,
NBC agrees to assist DUSA, as requested by DUSA, in preparing, submitting and
maintaining applications for such Approvals which shall be owned by DUSA.

         5.2 Information. Without limiting the provisions of Section 5.1 above,
NBC shall promptly provide DUSA all written and other information, in NBC's
possession or control, necessary or useful for DUSA to apply for, obtain and
thereafter maintain Approvals for the Light Source, including without limitation
information relating to [C.I.] of the Light Source or other such information
required to be submitted to the FDA (or its foreign equivalent) in the form of a
marketing application. Except as otherwise expressly provided herein, DUSA shall
restrict the use of such information solely for the foregoing purposes. Without
limiting the foregoing and subject to Section 5.5 below, NBC agrees to
immediately inform DUSA when any such information is no longer current and
reflective of current manufacturing practices, procedures or the Specifications
and to provide updated information to DUSA.

         5.3 Inspections. NBC shall permit the FDA, HPPB and other regulatory
agencies to conduct inspections of the Facility as the FDA or such other
regulatory agencies may request, and shall cooperate with the FDA, HPPB or such
other regulatory agencies with respect to such inspections and any related
matters. NBC agrees to give DUSA prior notice (when possible) of any such
inspections, and to keep DUSA informed about the results and conclusions of each
such regulatory inspection, including actions taken by NBC to remedy conditions
cited in such inspections. In addition, NBC shall allow DUSA or its
representative to assist in the preparation for and be present at such
inspections. NBC shall provide DUSA with copies of any written inspection
reports issued by such agencies and all correspondence between NBC and the
agency

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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

related thereto, including, but not limited to, FDA Form 483, Notice of
Observation, and all correspondence relating thereto. DUSA and its regulatory
consultants, agents, marketing partners or other third parties agreed upon in
advance by NBC, under reasonable confidentiality requirements, shall have
access, to all quality assurance and QS audits of NBC for the purposes of
assessment of regulatory compliance, to the buildings, records and areas of the
Facility involved in the manufacture, testing, storage and shipment of the Light
Source.

         5.4 DUSA Cooperation. DUSA agrees to keep NBC informed as to the status
of Approvals for Light Source supplied hereunder.

         5.5 Maintenance of Approvals. Notwithstanding anything herein to the
contrary, NBC shall not undertake any modifications to the Light Source design,
manufacturing, processing, critical suppliers or packaging that could delay or
otherwise impact the Approvals or other regulatory submissions, including
without limitation, regulatory product reviews, Investigational New Drug
applications (INDs), New Drug Applications (NDAs) or any other compliance status
without prior written agreement of DUSA. NBC shall obtain and maintain all
licenses, permits and registrations other than Approvals (e.g., business
licenses and the like) necessary to manufacture the Light Source and supply them
hereunder.

         5.6 Reporting. Pursuant to the FDA's and other applicable regulatory
agency's regulations and policies, DUSA may be required to report to such
regulatory agency information that reasonably suggests that a Light Source may
have caused or contributed to the death or serious injury or has malfunctioned
and that the Light Source would be likely to cause or contribute to a death or
serious injury if the malfunction were to recur. Accordingly, NBC agrees to
inform DUSA of any such information promptly after becoming aware of it so that
DUSA can comply with such reporting requirements. Furthermore, each shall assist
the other in the investigation of incidents and near incidents, as applicable,
to enable DUSA to fulfill all Directive (as defined below) obligations. Each
party shall inform the other of its awareness of any issue or potential
resulting in "unsafe" product. It is understood and agreed that reporting to
DUSA shall be within twenty-four (24) hours to enable DUSA to comply with
applicable reporting requirements.

         5.7 Regulatory Compliance. Each party shall copy the other with written
information regarding patient safety, Light Source efficacy or recalls. DUSA
shall be responsible for submitting any medical device report ("MDR") to the FDA
required by 21 CFR Part 803 et seq. as necessary. NBC will promptly assist DUSA
in any investigation relating to the potential need to file an MDR so that all
regulatory requirements can be met on a timely basis. NBC agrees to manufacture
the Light Source in accordance with current Good Manufacturing Practices ("GMP")
pursuant to Regulation 21 U.S.C. 360 et. seq. and 21 CFR Part 820 et seq. and
will permit DUSA to perform GMP audits upon reasonable notice and at agreed upon
times, at DUSA's expense. In addition, NBC shall manufacture the Light Source in
accordance with ISO 13485 and the Medical Device Directive 93/94/EEC dated June
14, 1993, as amended from time to time (the "Directive"), in order for the units
to be eligible for the CE mark. In addition, NBC shall provide to DUSA all
necessary technical file documentation to support the CE mark for the Light
Source. NBC shall operate under a certified "quality system" (i.e. ISO 13485)
for the production of the Light Source and shall maintain the necessary
supporting technical

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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

documentation for a period of at least seven (7) years after the last Light
Source unit has been shipped to DUSA.

                                    ARTICLE 6
                           PRODUCT WARRANTIES/SERVICE

         6.1 Product Warranties. NBC warrants and represents that:

                  6.1.1 Specifications. All Light Source supplied hereunder
shall upon delivery to DUSA or such other location as specified by DUSA comply
with the Specifications and shall conform with the information shown on the
certificate of conformance provided for the particular shipment according to
Section 3.2 hereof;

                  6.1.2 QS. The Facility, and all Light Source units supplied
hereunder upon delivery to DUSA or such other location as specified by DUSA,
meet all applicable regulatory requirements (including applicable QS
regulations) imposed by applicable regulatory agencies with respect to any
Approval;

                  6.1.3 Materials and Workmanship. Each Light Source shall be
free from defects in materials, workmanship and design for a period of [C.I.]
after its receipt by the end user (the "Warranty Period"). The foregoing
warranty set forth in this Section 6.1.3 [C.I.] or (ii) [C.I.];

                  6.1.4 Limitations. For avoidance of doubt, defects in the
manufacture of the [C.I.] shall be covered by the warranties in this Section
6.1; provided, however, that NBC [C.I.] in the [C.I.] in accordance with
applicable industry standards; and

                  6.1.5 No Encumbrance. Title to all Light Source supplied
hereunder shall pass as provided herein free and clear of any security interest,
lien, or other encumbrance.

         6.2 Disclaimer. EXCEPT AS EXPRESSLY PROVIDED IN SECTION 6.1, NBC MAKES
NO REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, AS TO THE LIGHT SOURCES, AND
NBC HEREBY EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE. NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
[C.I.]. EXCEPT FOR LIABILITY ARISING OUT OF ARTICLE 11 BELOW AND NOTWITHSTANDING
ANYTHING HEREIN TO THE CONTRARY, [C.I.].

         6.3 Warranty Service. During the Warranty Period, NBC agrees, [C.I.]
any Light Source failing to meet the warranties provided hereunder. Without
limiting the foregoing, NBC shall use best efforts to provide on-site warranty
repair service to end-users within [C.I.].

         6.4 Out-of-Warranty Service; Spare Parts. NBC hereby undertakes to
maintain repair capability for the Light Source during the term of this
Agreement and for [C.I.] thereafter (the "Support Period") subject to its
ability to source applicable components from third parties. In accordance with
the foregoing, NBC shall, if requested by DUSA, provide out-of-warranty service
on reasonable and customary terms and conditions, including reasonable
adjustments for increased labor costs during the Support Period. In addition
during the Support Period, NBC agrees to [C.I.] spare and replacement parts
[C.I.] and lead times therefor as may be required to

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Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

service and maintain Light Source units. Where there are no [C.I.], such spare
or replacement parts shall be provided [C.I.] and customary prices and lead
times, and in any event NBC's prices, terms and conditions for providing
services under this Section 6.4 shall be no less favorable to the customer than
those offered by NBC to a third party for similar services or parts.
Notwithstanding the foregoing, neither DUSA nor its customers shall have any
obligation to order any such service, or spare or replacement parts from NBC.

         6.5 Epidemic Failures. In addition to and without limiting the
warranties given above, where a defect in the design [C.I.] of the Light Source
which effects a [C.I.] of the total units of any particular Light Source model
(by SKU number) supplied hereunder (an "Epidemic Failure"), NBC shall, [C.I.],
remedy such Epidemic Failure in all units of such Light Source model (previously
supplied or to be supplied hereunder).

         6.6 Recalls. In the event that DUSA is required by any regulatory
agency to recall the Light Source or if DUSA voluntarily initiates a recall of
the Light Source and in either case such recall is a result of a breach of any
of the warranties under Section 6.1.1 through 6.1.3 above, [C.I.]. NBC will
notify DUSA of any information, which may lead to recall of any Light Source. In
case of a voluntary recall of the Light Source, DUSA will retrieve all units of
the Light Source, as the case may be, at its expense, with all direct expense:
(a) to be reimbursed by NBC immediately where recall is the sole responsibility
of NBC; and (b) to be borne by DUSA where recall is the sole responsibility of
DUSA. In situations of shared responsibility, costs will be shared equally by
the parties. In addition, NBC agrees to cooperate with and assist DUSA in
locating and retrieving, if necessary, units of the Light Source recalled for
any reason. A recall of DUSA's products (including the Light Source) for any
reasons other than those set forth in this Section 6.6 (including reasons due to
force majeure) above shall not affect DUSA's obligation to purchase Light Source
units in accordance with Article 2 herein above, as may be modified, or DUSA's
obligation under any outstanding purchase order hereunder.

         6.7 Documentation. NBC agrees to develop and provide to DUSA
documentation describing routine maintenance, service and care of the Light
Source. In addition, upon DUSA's request, NBC agrees to provide DUSA such other
information and documentation as DUSA may reasonably require in order to fulfill
standard maintenance and support requirements on reasonable and customary terms
and conditions.

                                    ARTICLE 7
                                   TRADEMARKS

         7.1 Packaging and Labeling. NBC shall be responsible for packaging and
labeling the Light Source delivered hereunder in accordance with DUSA's
Specifications, standard trade dress and style and all applicable regulatory
requirements.

         7.2 Trademarks. Without limiting the provisions of Section 7.1 above,
packaging materials and labels for the Light Source shall display the BLU-U(R)
Trademark and the DUSA trade name (collectively, the "DUSA Marks"). Accordingly,
DUSA hereby grants to NBC a license to use the DUSA Marks for the term of this
Agreement for the purposes of supplying the Light Source hereunder. The
ownership and all goodwill from the use of the DUSA Marks shall

                                      -10-

<PAGE>

                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

vest in and inure to the benefit of DUSA. NBC hereby acknowledges DUSA's
ownership rights in the DUSA Marks, and accordingly agrees that at no time
during or after the term of this Agreement to challenge or assist others to
challenge the DUSA Marks or the registration thereof or attempt to register any
trademarks, marks or trade names confusingly similar to such DUSA Marks. DUSA
obtains no rights to use, and may not use, the UBL Trademark for any purpose,
except to resell products manufactured by and purchased by DUSA from NBC, where
NBC has imprinted the UBL Trademark.

                                    ARTICLE 8
                              TERM AND TERMINATION

         8.1 Term. The term of this Agreement shall commence on the Effective
Date and continue in full force until November 5, 2008, unless terminated
earlier in accordance with this Article 8. This Agreement may be extended for an
additional period by mutual written agreement of NBC and DUSA [C.I.]; provided,
however, that neither NBC nor DUSA shall be obligated to approve any such
extension and shall have no liability whatsoever by reason of any failure to
agree on any such extension.

         8.2 Breach. This Agreement may be terminated and/or any outstanding
purchase order may be canceled by either party if the other party breaches any
material term or condition of this Agreement and fails to remedy the breach
within [C.I.] after being given written notice thereof. Notwithstanding the
foregoing, in the event of breach by either party, the other party's right to
terminate shall be stayed if the breaching party proposes a mutually agreeable
plan to remedy such breach within the foregoing [C.I.] and remedies such breach
within [C.I.] after being given written notice thereof. It is understood and
agreed that this Section 8.2 is subject to the provisions of Section 12.3 below,
excusing performance where performance is rendered impossible due to a Force
Majeure Event, including without limitation failure of suppliers, in each case
where such failure is beyond the reasonable control of the nonperforming party.
For avoidance of doubt, among other things a delay by NBC of more than [C.I.] of
the delivery date of any shipment of Light Source ordered in accordance with
Section 2.2 shall be deemed material.

         8.3 Convenience. Either party may terminate this Agreement upon twelve
(12) months' prior written notice to the other party.

         8.4 Termination for Insolvency. Either party may terminate this
Agreement and any outstanding purchase order if the other becomes the subject of
a voluntary or involuntary petition in bankruptcy or any proceeding relating to
insolvency, receivership, liquidation, or composition or the benefit of
creditors, if that petition or proceeding is not dismissed with prejudice [C.I.]
after filing.

         8.5 Survival. It is understood that termination or expiration of this
Agreement shall not relieve a party from any liability which, at the time of
such termination or expiration, has already accrued to the other party,
including NBC's obligations during the Support Period. The provisions of
Sections 3.3, 3.4, 4.2, 8.4 and 8.5 and Articles 1, 5, 6, 9, 11, and 12 shall
survive the termination of this Agreement for any reason. Except as otherwise
expressly provided in this

                                      -11-

<PAGE>

                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

Article 8, all other rights and obligations of the parties shall terminate upon
termination of this Agreement.

                                    ARTICLE 9
                                 CONFIDENTIALITY

         9.1 Confidential Information. The parties may from time to time
disclose to each other Confidential Information. "Confidential Information"
shall mean [C.I.]. Notwithstanding the foregoing or anything herein to the
contrary, Confidential Information shall not include any information that, in
each case as demonstrated by written documentation: (i) was already known to the
receiving party, other than under an obligation of confidentiality, at the time
of disclosure; (ii) was generally available to the public or otherwise part of
the public domain at the time of its disclosure to the receiving party; (iii)
became generally available to the public or otherwise part of the public domain
after its disclosure and other than through any act or omission of the receiving
party in breach of this Agreement; (iv) was subsequently lawfully disclosed to
the receiving party by a person other than the disclosing party; or (v) is
developed independently by the receiving party without use of or reliance on the
Confidential Information of the other party.

         9.2 Confidentiality. Each party agrees to hold and maintain in strict
confidence all Confidential Information of the other party. Without limiting the
foregoing, neither party shall use or disclose the Confidential Information of
the other party, except as otherwise permitted by this Agreement or as may be
necessary or useful to exercise its rights or perform its obligations under this
Agreement. Nothing contained in this Article 9 shall prevent either party from
disclosing any Confidential Information of the other party to (a) regulatory
agencies for the purpose of obtaining approval to distribute and market the
Light Source (or products incorporating the Light Source); provided, however,
that all reasonable steps are taken to maintain the confidentiality of such
Confidential Information to be disclosed; (b) to accountants, lawyers or other
professional advisors or in connection with a merger, acquisition or securities
offering, subject in each case to the recipient entering into an agreement to
protect such Confidential Information from disclosure; or (c) is required by law
or regulation to be disclosed; provided, however, that the party subject to such
disclosure requirement has provided written notice to the other party promptly
upon receiving notice of such requirement in order to enable the other party to
seek a protective order or otherwise prevent disclosure of such Confidential
Information.

                                   ARTICLE 10
                         REPRESENTATIONS AND WARRANTIES

         10.1 NBC. NBC represents and warrants that: (i) it has full power to
enter into this Agreement and to grant to DUSA the rights granted to DUSA
hereunder; (ii) it has obtained all necessary corporate approvals to enter into
and execute the Agreement; (iii) it has not entered and will not enter into any
agreements with any third party that are inconsistent with this Agreement; (iv)
NBC has not granted any rights to any third parties to subject matter which
would otherwise be included within the definition of NBC Technology; and (v) NBC
shall fully comply with the requirements of any and all applicable federal,
state, local and foreign laws,

                                      -12-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

regulations, rules and orders of any governmental body having jurisdiction over
the activities contemplated by this Agreement.

         10.2 DUSA. DUSA represents and warrants that: (i) it has full power to
enter into the Agreement; (ii) it has obtained all necessary corporate approvals
to enter and execute into this Agreement; (iii) it has not entered and will not
enter into any agreements with any third party that are inconsistent with this
Agreement; and (iv) DUSA shall fully comply with the requirements of any and all
applicable federal, state, local and foreign laws, regulations, rules and orders
of any governmental body having jurisdiction over the activities contemplated by
this Agreement and the distribution of the Light Source.

         10.3 Disclaimer. EXCEPT AS PROVIDED IN THIS ARTICLE 10 AND SECTION 6.1
ABOVE, NEITHER PARTY MAKES ANY WARRANTIES OR CONDITIONS (EXPRESS, IMPLIED,
STATUTORY OR OTHERWISE) WITH RESPECT TO THE SUBJECT MATTER HEREOF AND EACH PARTY
EXPRESSLY DISCLAIMS ANY SUCH ADDITIONAL WARRANTIES.

                                   ARTICLE 11
                                 INDEMNIFICATION

         11.1 DUSA. DUSA shall indemnify, defend and hold harmless NBC, its
directors, officers, employees, agents, successors and assigns from and against
[C.I.] against any of them by a third party alleging (i) [C.I.]; (ii) [C.I.];
and (iii) [C.I.], in each case subject to the requirements set forth in Section
11.3 below. Notwithstanding the foregoing, DUSA shall have no obligations under
this Article 11 for any liabilities, expenses or costs arising out of or
relating to claims covered under Section 11.2 below.

         11.2 NBC. NBC shall indemnify, defend and hold harmless DUSA, [C.I.],
in each case subject to the requirements set forth in Section 11.3 below.
Notwithstanding the foregoing, NBC shall have no obligations under this Article
11 for any liabilities, expenses or costs arising out of or relating to claims
covered under Section 11.1 above.

         11.3 Indemnification Procedure. A party that intends to claim
indemnification (the "Indemnitee") under this Article 11 shall promptly notify
the indemnifying party (the "Indemnitor") in writing of any third party claim,
suit or proceeding included within the indemnification described in this Article
11 above (each a "Claim") with respect to which the Indemnitee intends to claim
such indemnification, and the Indemnitor shall have sole control of the defense
and/or settlement thereof; provided that the Indemnitee shall have the right to
participate, at its own expense, with counsel of its own choosing in the defense
and/or settlement of such Claim. The indemnification under this Article 11 shall
not apply to amounts paid in settlement of any Claim if such settlement is
effected without the consent of the Indemnitor. The Indemnitee under this
Article 11, and its employees, at the Indemnitor's request and expense, provide
full information and reasonable assistance to Indemnitor and its legal
representatives with respect to such Claims.

                                      -13-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

         11.4 Insurance. Each party shall secure and maintain in effect during
the term of this Agreement and for a period of [C.I.] insurance policy(ies)
underwritten by a reputable insurance company and in a form and having limits of
at least [C.I.] in the aggregate for exposures related to the Light Source.
Additionally, each party shall [C.I.]. Upon request by the other party hereto,
certificates of insurance evidencing the coverage required above shall be
provided to the other party.

                                   ARTICLE 12
                                     GENERAL

         12.1 Governing Law. This Agreement shall be governed by, and construed
and interpreted in accordance with, the laws of the United States and the State
of New Jersey without reference to conflict of laws principles and excluding the
1980 U.N. Convention on Contracts for the International Sale of Goods.

         12.2 Disputes.

                  12.2.1 Negotiations. If NBC and DUSA, are unable to resolve
any dispute between them, either NBC or DUSA may, by written notice to the
other, have such dispute referred to [C.I.], for attempted resolution by good
faith negotiations within [C.I.]. Unless otherwise mutually agreed, the
negotiations between [C.I.] and at times within the period stated above [C.I.]
for consideration. If the parties are unable to resolve such dispute in
accordance with the aforementioned procedure or within [C.I.], either party
shall have the right to pursue any and all other remedies available to such
party, with the costs of such other remedies to be paid by the non-prevailing
party upon final judgment and the expiration of all appeals. Except as otherwise
provided in this Section 12.2, each party shall pay its own legal fees,
disbursements and other expenses incurred.

                  12.2.2 Arbitration. Any dispute arising between the parties
hereunder shall be resolved by arbitration in Cleveland, Ohio, according to the
Rules of the American Arbitration Association, and the award of the
arbitrator(s) shall be [C.I.]. The arbitrator, if a sole arbitrator, or the
chairman, if a panel of three arbitrators, shall be a lawyer with experience in
handling technical disputes and the other panel members shall have experience in
technical, engineering and/or medical device related cases. In the event a
demand for arbitration is filed pursuant hereto, the parties shall have the same
rights to discovery under the Federal Rules of Civil Procedure as if the dispute
had been filed as an original action in the United States District Court for the
jurisdiction in which the arbitration is brought. Any arbitration brought by
DUSA shall be held in Cleveland, Ohio, and the Court in Ohio shall have
jurisdiction and shall be authorized to enforce said rights as if the entire
dispute were pending before said Court. Any arbitration brought by NBC shall be
held in Boston, Massachusetts and the Court in Massachusetts shall have
jurisdiction and shall be authorized to enforce said rights as if the entire
dispute were pending before said Court.

         12.3 Force Majeure. Nonperformance of any party (except for the payment
of money and acceptance by DUSA of Light Source pursuant to an outstanding
purchase order hereunder) shall be excused to the extent that performance is
rendered impossible by strike, fire, earthquake,

                                      -14-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

flood, governmental acts or orders or restrictions, failure of suppliers, or any
other reason where failure to perform is beyond the reasonable control of the
nonperforming party (each a "Force Majeure Event"). Notwithstanding the
foregoing, NBC's delay of the delivery date of any shipment of Light Source
ordered in accordance with Section 2.2 shall not be excused for more than [C.I.]
pursuant to this Section 12.3. This Section 12.3 shall not be deemed to limit
DUSA's rights under Section 4.2 above.

         12.4 Delays. [C.I.] performance of the party's obligations under this
Agreement.

         12.5 Assignment. The parties agree that their rights and obligations
under this Agreement may not be assigned or otherwise transferred to a third
party without the prior written consent of the other party hereto. Any
assignment in violation of this Section 12.5 shall be null and void.
Notwithstanding the foregoing, either party may transfer or assign its rights
and obligations under this Agreement to a successor to all or substantially all
of its business or assets relating to this Agreement whether by sale, merger,
operation of law or otherwise; provided that such assignee or transferee has
agreed to be bound by the terms and conditions of this Agreement. Subject to the
foregoing, this Agreement shall be binding upon and inure to the benefit of the
parties hereto, their successors and assigns.

         12.6 Notices. Any notice or report required or permitted to be given or
made under this Agreement by either party shall be in writing and delivered to
the other party at its address indicated below (or to such other address as a
party may specify by notice hereunder) by courier or by registered or certified
airmail, postage prepaid, or by facsimile; provided, however, that all facsimile
notices shall be promptly confirmed, in writing, by registered or certified
airmail, postage prepaid. All notices shall be effective as of the date received
by the addressee.

         If to NBC:                   National Biological Corporation
                                      1532 Enterprise Parkway
                                      Twinsburg, OH 44087
                                      Attn: President
                                      Fax: (330) 425-9614

         with a copy to:              Kahn Kleinman, LPA
                                      2600 Erieview Tower
                                      1301 East Ninth Street
                                      Cleveland, OH  44114-1824
                                      Attn: Michael H. Diamant, Esq.
                                      Fax: (216) 623-4912

         If to DUSA:                  DUSA Pharmaceuticals, Inc.
                                      25 Upton Drive Suite 1208
                                      Wilmington, Massachusetts 01887
                                      Attn: Vice President, Operations
                                      Fax: (978) 657-9193

                                      -15-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

         with a copy to:              Reed Smith LLP
                                      Princeton Forrestal Village
                                      136 Main Street, Suite 250
                                      Princeton, New Jersey 08536
                                      Attn: Nanette W. Mantell, Esq.
                                      Fax: (609) 951-0824

         12.7 Confidential Terms. Except as expressly provided herein, each
party agrees not to disclose any terms of this Agreement to any third party
without the consent of the other party, except to prospective investors and to
such party's accountants, attorneys and other professional advisors or as
required by securities or other applicable laws, in which case the disclosing
party shall seek confidential treatment to the extent available.

         12.8 Headings. Headings included herein are for convenience only, do
not form a part of this Agreement and shall not be used in any way to construe
or interpret this Agreement.

         12.9 Non-Waiver. Any waiver of the terms and conditions hereof must be
explicitly in writing. The waiver by either of the parties of any breach of any
provision hereof by the other shall not be construed to be a waiver of any
succeeding breach of such provision or a waiver of the provision itself.

         12.10 Severability. Should any section, or portion thereof, of this
Agreement be held invalid by reason of any law, statute or regulation existing
now or in the future in any jurisdiction by any court of competent authority or
by a legally enforceable directive of any governmental body, such section or
portion thereof shall be validly reformed so as to approximate the intent of the
parties as nearly as possible and, if unreformable, shall be deemed divisible
and deleted with respect to such jurisdiction, but the Agreement shall not
otherwise be affected.

         12.11 Independent Contractors. The relationship of DUSA and NBC
established by this Agreement is that of independent contractors. Nothing in
this Agreement shall be construed to create any other relationship between DUSA
and NBC. Neither party shall have any right, power or authority to assume,
create or incur any expense, liability or obligation, express or implied, on
behalf of the other.

         12.12 Entire Agreement. The terms and provisions contained in the
Agreement, including the Exhibits hereto, constitute the entire agreement
between the parties and shall supersede all previous communications,
representations, agreements or understandings, either oral or written, between
the parties including the Original Purchase and Supply Agreement except to the
extent the provisions of such Original Purchase and Supply Agreement are
restated herein. No agreement or understanding varying or extending this
Agreement shall be binding upon either party hereto, unless set forth in a
writing which specifically refers to the Agreement signed by duly authorized
officers or representatives of the respective parties, and the provisions hereof
not specifically amended thereby shall remain in full force and effect.

                                      -16-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

         12.13 Counterparts. This Agreement may be executed in counterparts,
each of which shall be deemed an original, but which together shall constitute
one and the same instrument.

         IN WITNESS WHEREOF, the parties hereto have caused their duly
authorized representatives to execute this Agreement.

DUSA PHARMACEUTICALS, INC.           NATIONAL BIOLOGICAL CORPORATION

By: /s/ Mark Carota                  By:    /s/ Mark W. Friedman
    -------------------------            ---------------------------------------

Name: Mark Carota                    Name:  Mark W. Friedman

Title: V.P. Operations               Title: President & Chief Operating Officer

                                      -17-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                  EXHIBIT "A-1"

                                  LIGHT SOURCE

                                     [C.I.]

                                      -18-

<PAGE>

                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                  EXHIBIT "A-2"

                             SOURCE CONTROL DRAWING

                                     [C.I.]

                                      -19-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                   EXHIBIT "B"

                             FORM OF PURCHASE ORDER

DUSA
DUSA Pharmaceuticals, Inc.                      PURCHASE
25 Upton Drive                                  ORDER NO.
Wilmington, MA 01887                                         Confirmation Only
978-657-7500 Phone                                           Do not Duplicate


REQUISITION NUMBER   ISSUE DATE   F.O.B  TERMS                        ORIGINATOR

TAX EXEMPT STATUS: TAX EXEMPT [ ]      TAXABLE [ ]   TAX EXEMPT NO.   SHIP VIA

VENDOR I.D. NUMBER                                 Ship to: DUSA Pharmaceuticals
                                                         25 Upton Drive
                                                         Wilmington, Ma 01887

<TABLE>
<CAPTION>
                                       REV.
LINE   QUANTITY   U/M   ITEM NUMBER   LEVEL   DESCRIPTION   DUE DATE   UNIT PRICE   TOTAL
----   --------   ---   -----------   -----   -----------   --------   ----------   -----
<S>    <C>        <C>   <C>           <C>     <C>           <C>        <C>          <C>
</TABLE>

NOTICE: DUSA Pharmaceuticals must be notified of any changes in the product(s)
or service(s) provided so that DUSA may determine whether the changes will
affect the quality of the finished product.

The above named supplier hereby agrees that their performance on this order
conveys and confirms their acceptance / agreement to the terms and conditions of
this order which may not be changed are mutually binding on the parties
herewith, and supercedes all and every prior oral and / or written agreements,
except those which are refercenced and / or incorporated herein on this purchase
order and its attachments articles and exhibits.

_______________________________                  _______________________________
REFER ALL QUESTIONS TO (BUYER)      SUPPLIER          AUTHORIZED SIGNATURE

                                      -20-

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                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                   EXHIBIT "C"

                                     PRICING

                                     [C.I.]

                                      -21-

<PAGE>

                                                                  Execution Copy

Note: Certain portions of this document have been marked "[c.i.]" to indicate
that confidential treatment has been requested for this confidential
information. The confidential portions have been omitted and filed separately
with the Securities and Exchange Commission.

                                   EXHIBIT "D"

                               ACCEPTANCE TESTING

                                     [C.I.]

                                      -22-