EXHIBIT 5.1

[DECHERT LETTERHEAD]


May 6, 2002

Unigene Laboratories, Inc.
110 Little Falls Road
Fairfield, New Jersey 07004

Re:   Registration Statement on Form S-1
      Registration No. 333-87104

Gentlemen and Ladies:

We have acted as special counsel to Unigene Laboratories, Inc., a Delaware
corporation (the "Company"), in connection with a Registration Statement on Form
S-1 (the "Registration Statement") filed on April 26, 2002 by the Company with
the Securities and Exchange Commission under the Securities Act of 1933, as
amended, for the registration for resale of up to 2,700,000 shares of the
Company's common stock, par value $.01 per share (the "Common Stock"), by (i)
The Tail Wind Fund, Ltd., a British Virgin Islands limited liability company
("Tail Wind"), of up to 2,000,000 shares of Common Stock (the "Tail Wind
Shares") issuable to Tail Wind pursuant to the Settlement Agreement, dated April
9, 2002, between Tail Wind and the Company (the "Tail Wind Settlement
Agreement"); (ii) Annette North ("North"), of up to 400,000 shares of Common
Stock (the "North Shares") issuable to North pursuant to a letter agreement,
dated August 29, 2000 and as amended on September 29, 2000, between North and
the Company (the "North Agreement"); and (iii) Patrick Tedesco ("Tedesco") of up
to 300,000 shares of Common Stock (the "Tedesco Shares") issuable to Tedesco
pursuant to a letter agreement, dated July 25, 2001, between Tedesco and the
Company (the "Tedesco Agreement").

For purposes of this opinion, we have examined the Registration Statement and
the relevant exhibits thereto, including the Tail Wind Settlement Agreement, the
North Agreement, and the Tedesco Agreement.

We also have examined and relied upon a copy of the Company's Certificate of
Incorporation, certified by the Secretary of State of the State of Delaware,
copies of the Company's By-Laws and certain resolutions adopted by the Board of
Directors of the Company, each certified by the Corporate Secretary of the
Company.

We have examined such other documents and made such other investigations as we
have deemed necessary to form a basis for the opinion hereinafter expressed. In
examining the foregoing documents, we have assumed the authenticity of documents
submitted to us as originals, the genuineness of all signatures, the conformity
to authentic original documents of documents submitted to us as copies, and the
accuracy of the representations and statements included therein.



Unigene Laboratories, Inc.

May 6, 2002

Page 2

Based on the foregoing, and subject to the assumptions and qualifications set
forth herein, we are of the opinion that: (i) the Tail Wind Shares issued
pursuant to the Tail Wind Settlement Agreement have been duly authorized for
issuance; and when the certificates representing the Tail Wind Shares in the
form of the specimen certificate examined by us have been countersigned by an
authorized officer of the transfer agent for the Company, and when delivered by
the Escrow Agent (as defined in the Tail Wind Settlement Agreement) to Tail Wind
in accordance with the terms of the Tail Wind Settlement Agreement and the
Escrow Agreement (as defined in the Tail Wind Settlement Agreement), the Tail
Wind Shares will be validly issued, fully paid and non-assessable; (ii) the
Tedesco Shares issuable pursuant to the Tedesco Agreement have been duly
authorized for issuance; and when the certificates representing the Tedesco
Shares in the form of the specimen certificate examined by us have been
countersigned by an authorized officer of the transfer agent for the company,
and when issued and delivered by the Company to Tedesco in accordance with the
terms of the Tedesco Agreement, the Tedesco Shares will be validly issued, fully
paid and non-assessable; (iii) the North Shares issuable pursuant to the North
Agreement have been duly authorized for issuance; and when the certificates
representing the North Shares in the form of the specimen certificate examined
by us have been countersigned by an authorized officer of the transfer agent for
the Company, and when issued and delivered by the Company to North in accordance
with the terms of the North Agreement, the North Shares will be validly issued,
fully paid and non-assessable.

We express no opinion as to the applicability of compliance with, or effect of
federal law or the law of any jurisdiction other than the General Corporation
Law of the State of Delaware.

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name in the Prospectus contained
therein under the caption "Legal Matters." In giving such consent we do not
admit that we are in the category of persons whose consent is required under
Section 7 of the Securities Act or under the rules and regulations promulgated
by the Securities and Exchange Commission.

Very truly yours,

/s/ Dechert