Exhibit 5.1

               [Dickstein Shapiro Morin & Oshinsky LLP Letterhead]

                               September 29, 2003

Board of Directors
Discovery Laboratories, Inc.
350 South Main Street, Suite 307
Doylestown, Pennsylvania 18901

                         Discovery Laboratories, Inc.--
                 Amended and Restated 1998 Stock Incentive Plan

Ladies and Gentlemen:

            We have acted as counsel for Discovery Laboratories, Inc., a
Delaware corporation (the "Company"), in connection with the preparation of the
Company's registration statement on Form S-8, and any amendments thereto (the
"Registration Statement"), as filed with the Securities and Exchange Commission
(the "Commission") under the Securities Act of 1933 (the "Securities Act"), for
the registration under the Securities Act of up to 1,420,000 shares (the
"Shares") of the Company's common stock, par value $0.001 per share (the "Common
Stock"), to be issued upon the exercise of stock options granted under the
Company's Amended and Restated 1998 Stock Incentive Plan (the "Plan") as a
result of an amendment to such Plan increasing the number of shares issuable
under such Plan from 5,150,000 to 6,570,000. Capitalized terms used and not
defined in this opinion have the meanings ascribed to them in the Registration
Statement. You have requested that we furnish our opinion as to matters
hereinafter set forth.

            In rendering this opinion, we have relied upon, among other things,
our examination of certain records of the Company, including, without
limitation, the Company's Restated Certificate of Incorporation, the Company's
Bylaws, as amended, and resolutions of the Board of Directors. We have also
examined certificates of the Company's officers and of public officials and have
reviewed such questions of law and made such other inquiries, as we have deemed
necessary or appropriate for the purpose of rendering this opinion. As to
various questions of fact material to this opinion, we have also relied upon
representations and warranties of the Company and upon such certificates and
other instruments of officers of the Company and public officials furnished to
us by the Company, in each case without independent investigation or
verification.


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            In addition, without any independent investigation or verification,
we have assumed (i) the genuineness of all signatures, (ii) the authenticity of
all documents submitted to us as originals and the conformity with the original
documents of all documents submitted to us as certified, conformed or
photostatic copies, (iii) the authority of all persons signing any document
other than the officers of the Company, where applicable, signing in their
capacity as such, (iv) the enforceability of all the documents we have reviewed
in accordance with their respective terms against the parties thereto, and (v)
the truth and accuracy of all matters of fact set forth in all certificates and
other instruments furnished to us.

            Based upon the foregoing, and subject to the limitations,
qualifications and assumptions set forth herein, we are of the opinion that the
Shares offered by the Company pursuant to the Registration Statement, when
issued and paid for in accordance with the Plan, will be validly issued, fully
paid and nonassessable.

            No opinion is expressed herein with respect to any laws other than
the General Corporation Law and the Constitution of the State of Delaware. No
opinion is expressed as to the effect that the law of any other jurisdiction may
have upon the subject matter of the opinion expressed herein under conflicts of
law principles, rules and regulations or otherwise. We assume no obligation to
supplement this letter if any applicable laws change after the date hereof or if
we become aware of any new facts that might effect any view expressed herein
after the date hereof.

            We hereby consent to the filing of this opinion as Exhibit 5.1 to
the Registration Statement. In giving this consent, we do not admit that we are
within the category of persons whose consent is required by Section 7 of the
Securities Act or the rules and regulations promulgated thereunder by the
Commission.

            The foregoing opinion is delivered to the Board of Directors of the
Company in connection with the Registration Statement, and may not be relied
upon by any other person or for any other purpose.

            We wish to call your attention to the fact that the fair market
value of all securities of the Company that are beneficially owned by attorneys
of this Firm exceeds $50,000.

                                        Very truly yours,


                                /s/ Dickstein Shapiro Morin & Oshinsky LLP


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