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                                                                   Exhibit 99(a)

[DUSA LOGO]
INNOVATION IN PHOTODYNAMIC THERAPY

DUSA PHARMACEUTICALS, INC. (R)
FOR RELEASE AT 8:00 A.M.

                   DUSA PHARMACEUTICALS REPORTS SECOND QUARTER
                   CORPORATE HIGHLIGHTS AND FINANCIAL RESULTS

WILMINGTON, MA. AUGUST 10TH, 2004 - DUSA Pharmaceuticals, Inc. (NASDAQ NMS:
DUSA) reported today its corporate highlights and financial results for the
second quarter ended June 30th, 2004.

CORPORATE HIGHLIGHTS

As reported earlier, Q2 2004 end-user Levulan(R) Kerastick(R) net sales to
physicians totaled 17,910, including 1,908 sold by Coherent-AMT, our Canadian
marketing and distribution partner. This compared to 12,054 Kerastick units sold
during Q1 2004 and 1,914 during Q2 2003, neither of which included any Canadian
sales. The number of BLU-U(R) units placed in doctors' offices during the
quarter also increased significantly, by 241, including 58 in Canada, compared
with 128 during Q1 2004 and zero during Q2 2003. At the end of Q2 2004, there
were 775 BLU-U units in doctors' offices, as compared to 534 at the end of Q1
2004, and 323 at the end of Q2 2003.

By the end of the current quarter, DUSA reached its previously announced target
of 16 sales representatives and area managers. In light of the continued strong
growth in sales, management has decided to continue hiring, in order to reach a
total sales force of approximately 23 individuals (including sales
representatives, area managers and an Associate VP of sales) by the end of Q3.
Management believes that this number will allow DUSA to serve all of its current
key markets with direct representatives. We expect to maintain approximately
this number for at least the remainder of 2004.

Due to the demand caused by increasing sales volumes, DUSA is also pleased to
announce that during the current quarter, we began producing and shipping
Kerastick units from our FDA-approved manufacturing facility at our Wilmington,
MA headquarters. There were no significant start-up issues, and production will
be gradually ramped up as sales continue to increase.

On June 21, 2004, DUSA signed an Amended and Restated Purchase and Supply
Agreement with National Biological Corporation ("NBC"), the manufacturer of our
BLU-U light source. This agreement eliminated certain exclusivity clauses and
made other modifications to the original agreement, giving both parties greater
flexibility related to the development and manufacture of new light sources, and
the associated technology within the field of PDT. DUSA also maintains the
ability to order additional BLU-U light sources from NBC, if we so choose. DUSA
paid $110,000 to NBC upon execution of the agreement, which will be amortized
over the remaining term of the agreement, expiring November 5, 2008.

In light of the growing interest in blue light treatment of acne, and the
significant increase in BLU-U sales during the first half of 2004, our inventory
of original BLU-U units has been depleted more rapidly than initially expected
(approximately 160 units remained in stock at the end of Q2). Therefore, the
Company is aggressively evaluating its options

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with respect to reclaiming any DUSA-owned light units in the field that are not
being actively used, ordering more BLU-U(R) units, and/or developing alternative
light sources. However, until new light sources are available, likely in H1
2005, BLU-U(R) revenues are expected to be limited by supply constraints.

During the quarter, DUSA announced the initiation of a Phase II clinical trial
on Levulan PDT in the treatment of photodamaged skin, and a Phase II pilot study
using Levulan PDT for the treatment of high-grade dysplasia in Barrett's
esophagus. The company expects to initiate a Phase II study on Levulan PDT for
the treatment of acne vulgaris during the third quarter. There were also a
number of peer-reviewed scientific articles related to the use of Levulan(R)
published in the dermatology literature, as well as numerous lectures and
presentations at scientific meetings and CME events.

Other developments during the quarter included an announcement from CMS of
improved reimbursement for our procedure when the treatment is administered in
hospital out-patient clinics; agreements with Cynosure and Lumenis related to
the use of their light sources as part of our Phase II photodamage skin trial;
and the addition of DUSA's stock to the Russell 3000 index.

Dr. D. Geoffrey Shulman, DUSA's President and CEO, stated "We are very pleased
with the strong increases in Kerastick and BLU-U sales this quarter. With the
March 2004 financing, we are well-positioned to make the key short-term
investments needed to add significant long-term value, including expanding our
sales force, developing the photodamaged skin and acne indications, and
defending our intellectual property as required. Other than the unknown effect
of seasonal factors on sales during the upcoming third quarter, we look forward
to continued strong sales growth as we become a significant competitor in the
field of dermatology and beyond."

FINANCIAL HIGHLIGHTS:

For the three months ended June 30, 2004, DUSA's net loss was ($4,196,000), or
($0.25) per common share, compared to a net loss of ($3,811,000), or ($0.27) per
common share in 2003. This higher loss is primarily due to a significant
increase in legal and marketing & sales expenses, partially offset by the
increase in Kerastick and BLU-U product sales (net of a related increase in cost
of product sales). The legal expenses were primarily related to the costs of the
patent litigation trial in Australia, which ended in April. A court decision in
this matter is not expected to be rendered until late 2004. However, legal costs
are expected to decline during the second half of the year, unless DUSA enters
into additional significant legal activities. On the other hand, the increased
marketing & sales expenses were directly related to the increased size of the
sales force, and these expenses are expected to continue to rise through the
remainder of 2004, until the number of representatives stabilizes.

Revenues for the three months ended June 30, 2004 were $2,176,000, compared to
$147,000 in 2003. During the current quarter, Kerastick and BLU-U sales to
physicians were $1,304,000 and $872,000 respectively, including initial sales in
Canada by Coherent-AMT, our Canadian marketing and distribution partner, whereas
revenues for 2003 were totally comprised of Kerastick sales to physicians by our
US distribution channels. This significant increase in revenues is largely the
result of the efforts of our sales force since its launch in October 2003. In
addition, the increase in BLU-U placements was caused, in part, by our ability
to sell the BLU-U to physicians as a stand alone device for the treatment of
moderate inflammatory acne vulgaris. Although the level of Kerastick sales to
end-users for 2004 is much higher than those in the prior year, Kerastick sales
must continue to increase significantly in order for DUSA to become

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profitable.

Research and development costs for the three months ended June 30, 2004 were
$1,577,000 as compared to $1,449,000 in 2003. This increase reflects the
preparation work associated with initiating our Phase II photodamaged skin
trial, protocol finalization for our acne trial, and the start of our Phase II
pilot study for Barrett's esophagus, offset, in part, by lower third-party
expenditures for our completed FDA mandated Phase IV clinical study of the
long-term efficacy of our marketed Levulan PDT product for actinic keratoses.

Marketing and sales costs for the three months ended June 30, 2004 were
$1,699,000 as compared to $533,000 in 2003. This increase is mainly attributable
to the effects of the hiring and launch of our direct sales force starting in
the fourth quarter of 2003, and related marketing and sales activities.

General and administrative costs for the three months ended June 30, 2004
increased to $2,403,000 as compared to $1,680,000 in 2003. This increase was
mainly attributable to higher legal expenses amounting to $1,331,000 during the
current quarter, as compared to $903,000 in the comparable 2003 period, due
primarily to patent litigation costs.

Total cash, cash equivalents, and United States government securities, including
investments classified as long-term, as of June 30, 2004 were $55,964,000,
compared to $37,969,000 at the end of 2003. This increase is primarily due to
$24,750,000 of gross proceeds raised from the private placement in March 2004
and an additional $3,712,000 of gross proceeds raised in April 2004, as all of
the Additional Investment Rights from the private placement were exercised.
Long-term debt that was secured in 2002 to construct our manufacturing facility
was repaid in June 2004 based on the increase in the renewal rate as compared to
the current and future yields that are expected to be earned on our investments.

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DUSA PHARMACEUTICALS, INC.
CONDENSED CONSOLIDATED BALANCE SHEETS

<TABLE>
<CAPTION>
                                                 JUNE 30,
                                                  2004       DECEMBER 31,
                                               (UNAUDITED)      2003
                                               -----------   -----------
<S>                                            <C>           <C>
ASSETS

CURRENT ASSETS
   Cash, and cash equivalents                  $30,057,306   $ 4,294,482
   United States government securities          25,767,385    30,284,841
   Accounts receivable                             766,178       229,483
   Inventory                                       891,280       712,831
   Other current assets                          1,532,120     1,534,209
                                               -----------   -----------
      TOTAL CURRENT ASSETS                      59,014,269    37,055,846
   Restricted cash                                 139,847       139,213
   United States government securities                   -     3,250,940
   Property and equipment, net                   3,772,582     4,251,489
                                               -----------   -----------
TOTAL ASSETS                                   $62,926,698   $44,697,488
                                               ===========   ===========

LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES
   Accounts payable and accrued expenses       $ 2,590,733   $ 2,818,039
   Current maturities of long-term debt                  -       270,000
   Deferred revenue                                323,939       129,900
                                               -----------   -----------
     TOTAL CURRENT LIABILITIES                   2,914,672     3,217,939
   Long-term debt, net of current maturities             -     1,247,500
                                               -----------   -----------
TOTAL LIABILITIES                                2,914,672     4,465,439
TOTAL SHAREHOLDERS' EQUITY                      60,012,026    40,232,049
                                               -----------   -----------
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY     $62,926,698   $44,697,488
                                               ===========   ===========
</TABLE>

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DUSA PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(AMOUNTS ARE IN US DOLLARS)

<TABLE>
<CAPTION>
                                                THREE MONTHS ENDED              SIX MONTHS ENDED
                                                     JUNE 30                        JUNE 30
                                                   (UNAUDITED)                     (UNAUDITED)
                                           ----------------------------    ----------------------------
                                               2004           2003             2004            2003
                                           ------------    ------------    ------------    ------------
<S>                                        <C>             <C>             <C>             <C>
REVENUES
   Product sales and rental income         $  2,176,028    $    147,275    $  3,431,713    $    290,645

OPERATING COSTS
   Cost of product sales and royalties        1,068,711         824,027       1,894,716       1,577,331
   Research and development                   1,577,294       1,448,600       3,265,060       2,964,991
   Marketing and sales                        1,699,145         532,978       3,066,603       1,063,490
   General and administrative                 2,402,546       1,679,750       4,577,793       3,155,021
                                           ------------    ------------    ------------    ------------
TOTAL OPERATING COSTS                         6,747,696       4,485,355      12,804,172       8,760,833
                                           ------------    ------------    ------------    ------------
LOSS FROM OPERATIONS                         (4,571,668)     (4,338,080)     (9,372,459)     (8,470,188)
                                           ------------    ------------    ------------    ------------

OTHER INCOME
   Interest income                              375,581         526,964         774,718       1,093,099
                                           ------------    ------------    ------------    ------------
NET LOSS                                   $ (4,196,087)   $ (3,811,116)   $ (8,597,741)   $ (7,377,089)
                                           ============    ============    ============    ============
BASIC AND DILUTED NET LOSS PER COMMON
   SHARE                                   $      (0.25)   $      (0.27)   $      (0.55)   $      (0.53)
                                           ============    ============    ============    ============

WEIGHTED AVERAGE NUMBER OF COMMON SHARES
   OUTSTANDING                               16,727,111      13,932,424      15,764,792      13,912,579
                                           ============    ============    ============    ============
</TABLE>

DUSA Pharmaceuticals, Inc. is a biopharmaceutical company engaged primarily in
the development of Levulan(R) Photodynamic Therapy (PDT) and Photodetection (PD)
for multiple medical indications, with its primary focus in dermatology. PDT and
PD utilize light-activated compounds such as Levulan(R) to induce a therapeutic
or detection effect. DUSA is a world leader in topically or locally applied PDT
and PD. The Company maintains offices in Wilmington, MA, Valhalla, NY, and
Toronto, Ontario.

Except for historical information, this news release contains certain
forward-looking statements that represent our current expectations and beliefs
concerning future events, and involve certain known and unknown risk and
uncertainties. These forward-looking statements relate to DUSA's expectations of
increasing its sales force and the sales forces' ability to serve key markets,
anticipated revenues generated by BLU-U(R) sales, expectations with regard to
the launch of clinical studies, expectations of DUSA's position regarding
developing new indications and defending its intellectual property, requirements
for future profitability, expected levels of legal expenses, and the timing of a
decision in the Australian patent dispute. These forward-looking statements are
further qualified by important factors that could cause actual results to differ
materially from those in the forward-looking statements. These factors include,
without limitation,

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the increasing market acceptance of our products, changing market and regulatory
conditions, the impact of competitive products and pricing, changes to DUSA's
corporate strategy, the reliance on third-parties for the marketing, sale,
production and manufacture of our products, the maintenance of our patent
portfolio, and other risks and uncertainties identified in DUSA's Form 10-K for
the year ended December 31, 2003.

For further information contact: D. GEOFFREY SHULMAN, MD, President and CEO or
SHARI LOVELL, Director, Shareholder Services Tel: 416.363.5059 Fax 416.363.6602
or visit www.dusapharma.com