SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549

                                   FORM 12b-25

                         Commission File Number 0-26422

                           NOTIFICATION OF LATE FILING

(Check One):
|_| Form 10-K |_| Form 11-K |_| Form 20-F |X| Form 10-Q |_| Form N-SAR

                                For Period Ended:
                                  June 30, 1999

                       |_| Transition Report on Form 10-K
                       |_| Transition Report on Form 20-F
                       |_| Transition Report on Form 11-K
                       |_| Transition Report on Form 10-Q
                       |_| Transition Report on Form N-SAR

                        For the Transition Period Ended:
                        --------------------------------

Nothing in this form shall be construed to imply that the Commission has
verified any information contained herein.

If the notification relates to a portion of the filing checked above, identify
the Item(s) to which the notification relates:

NOT APPLICABLE
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PART I - REGISTRANT INFORMATION

DISCOVERY LABORATORIES, INC.
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      Full Name of Registrant

ANSAN PHARMACEUTICALS, INC.
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      Former Name if Applicable

350 South Main Street, Suite 307
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      Address of Principal Executive Office (Street and Number)


Doylestown, PA  18901
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      City, State and Zip Code

PART II - RULES 12b-25(b) AND (c)

      If the subject report could not be filed without unreasonable effort or
expense and the registrant seeks relief pursuant to Rule 12b-25(b), the
following should be completed. (Check appropriate box.) |X| Yes |_| No

|X|  (a)    The reasons described in reasonable detail in Part III of this form
            could not be eliminated without unreasonable effort or expense;

|X|  (b)    The subject annual report, semi-annual report, transition report on
            Form 10-K, 20-F, 11-K or N-SAR, or portion thereof, will be filed on
            or before the 15th calendar day following the prescribed due date;
            or the subject quarterly report or transition report on Form 10-Q,
            or portion thereof will be filed on or before the fifth calendar day
            following the prescribed due date; and

     (c)    The accountant's statement or other exhibit required by Rule
            12b-25(c) has been attached if applicable.

PART III - NARRATIVE

State below in reasonable detail the reasons why Form 10-K, 11-K, 20-F, 10-Q,
N-SAR, or the transition report or portion thereof, could not be filed within
the prescribed time period.

The Registrant was unable to file the Quarterly Report on Form 10-QSB for the
quarter ended June 30, 1999 (the "Report") without unreasonable effort or
expense due to the delays in gathering information from the Registrant's
professional advisors for inclusion therein.

PART IV - OTHER INFORMATION

(1) Name and telephone number of person to contact in regard to this
notification

Kenneth G. Alberstadt                                    (212) 299-8640
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       (Name)                                    (Area Code) (Telephone Number)

(2) Have all other periodic reports required under Section 13 or 15(d) of the
Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of
1940 during the preceding 12 months or for such shorter period that the
registrant was required to file such report(s) been filed? If answer is no,
identify report(s). |X| Yes |_| No


(3) Is it anticipated that any significant change in results of operation for
the corresponding period for the last fiscal year will be reflected by the
earnings statements to be included in the subject report or portion thereof?
|X| Yes |_| No

      If so: attach an explanation of the anticipated change, both narratively
and quantitatively, and, if appropriate, state the reasons why a reasonable
estimate of the results cannot be made.

Explanation:

For the three and six month periods ended June 30, 1998, the Registrant incurred
a charge for write off of in-process research and development costs amounting to
$8,230,000.00. No such charge was incurred in the corresponding periods in 1999.

                          DISCOVERY LABORATORIES, INC.
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                  (Name of Registrant as Specified in Charter)

            has caused this notification to be signed on its behalf by the
            undersigned hereunto duly authorized.

Date                            By
      August 17, 1999               /s/ Robert J. Capetola
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                                    Robert J. Capetola, Ph.D.
                                    President and Chief Executive Officer

Instruction: The form may be signed by an executive officer of the registrant or
by any other duly authorized representative. The name and title of the person
signing the form shall be typed or printed beneath the signature. If the
statement is signed on behalf of the registrant by an authorized
representative(other than an executive officer), evidence of the
representative's authority to sign on behalf of the registrant shall be filed
with the form.

                                    ATTENTION

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Intentional misstatements or omissions of fact constitute Federal criminal
violations. (See 18 U.S.C. 1001)
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