EXHIBIT 5.1

(Jeffers, Shaff & Falk, LLP Letterhead)

July 30, 2001

Peregrine Pharmaceuticals, Inc.
14272 Franklin Avenue, Suite 100
Tustin, California 92780-7017

Re:     Registration Statement on Form S-3
        Peregrine Pharmaceuticals, Inc., Common Stock, par value $.001 per share

Ladies and Gentlemen:

We are counsel for Peregrine Pharmaceuticals, Inc., a Delaware corporation (the
"Company(degree)), in connection with the preparation of the Registration
Statement on Form S-3 (the "Registration Statement") as to which this opinion is
a part, filed with the Securities and Exchange Commission (the "Commission") on
July 31, 2001 for the resale of up to [11,049,991] shares of common stock, $.001
par value, of the Company by selling stockholders (the "Shares").

In connection with rendering our opinion as set forth below, we have reviewed
and examined originals or copies of such corporate records and other documents
and have satisfied ourselves as to such other matters as we have deemed
necessary to enable us to express our opinion hereinafter set forth.

Based upon the foregoing, it is our opinion that:

The issued Shares covered by the Registration Statement have been validly
issued and are fully paid and nonassessable. The Shares to be issued upon the
exercise of certain warrants, as covered by the Registration Statement, when
issued in accordance with the terms and conditions set forth in the Registration
Statement, will be duly authorized, validly issued, fully paid and
nonassessable.

We hereby consent to the filing of this opinion as an Exhibit to the
Registration Statement and to the reference to this firm under the caption
"Legal Matters" in the prospectus included in the Registration Statement.

Very truly yours,


/S/ JEFFERS, SHAFF & FALK, LLP
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JEFFERS, SHAFF & FALK, LLP