EXHIBIT 2.1

                          AGREEMENT AND PLAN OF MERGER

     Agreement  and Plan of Merger,  dated as of May 12,  2003,  by and  between
Pharmaceutical  Resources,  Inc., a New Jersey corporation (the "Company"),  and
Pharmaceutical  Resources,  Inc.,  a  wholly-owned  Delaware  subsidiary  of the
Company  newly-formed  solely for the purpose of reincorporating  the Company in
the State of Delaware ("PRI (DEL)").

     The Company owns all of the issued and outstanding  shares of capital stock
of PRI (DEL). In consideration of the mutual promises,  covenants and agreements
contained  herein,  the Company and PRI (DEL),  intending  to be legally  bound,
hereby agree as set forth below.

     1. Merger of the Company with and into PRI (DEL). At the Effective Time, as
defined in Section 5 of this Agreement and Plan of Merger, (a) the Company shall
merge with and into PRI (DEL),  (b) the separate  existence of the Company shall
cease to exist  and (c) PRI  (DEL)  shall be the  surviving  corporation  in the
merger (the  "Surviving  Corporation")  and shall  continue its existence  under
Delaware law (the "Merger").

     2.  Certificate of Incorporation  and Bylaws of the Surviving  Corporation.
The Certificate of  Incorporation  and Bylaws of PRI (DEL) at the Effective Time
shall  continue  to be  the  Certificate  of  Incorporation  and  Bylaws  of the
Surviving  Corporation,  respectively,  subject  to  any  future  amendments  or
deletions thereto in accordance with applicable law.

     3. Directors and Officers of the Surviving  Corporation.  The directors and
officers of the Company immediately prior to the Effective Time shall become the
respective directors and officers of the Surviving Corporation,  who shall serve
in accordance with applicable law and until their respective successors are duly
qualified and elected.

     4. Cancellation, Conversion and Continuance of Shares.

            (a) PRI (DEL) Shares. At the Effective Time, all shares of capital
stock of PRI (DEL) owned by the Company immediately prior to the consummation of
the Merger shall be cancelled.

            (b) Company  Shares.  Each issued and  outstanding  share,  and each
share then held in the treasury,  of the common stock of the Company  shall,  by
virtue of the Merger and without  any action on the part of the holder  thereof,
be automatically  converted at the Effective Time into one share of common stock
of PRI  (DEL).  The terms and  conditions  of each stock  option and  warrant to
purchase shares of the Company's common stock  outstanding  immediately prior to
the consummation of the Merger shall remain the same, except that such option or
warrant shall be an option or warrant, as the case may be, to purchase shares of
PRI (DEL) common stock.

            The  consummation  of the Merger  shall not be deemed a  transaction
that  constitutes  a "change of  control,"  as such term is defined in the stock
option plans or agreements of the Company under which options to purchase shares
of its common stock have been  granted.  Accordingly,  the terms of  outstanding
stock options of the Company shall not be affected as a result of the Merger.

            It will not be necessary for shareholders of the Company to exchange
their existing  stock  certificates  representing  shares of common stock of the
Company for stock certificates representing shares of PRI (DEL) common stock. In
the event,  however,  such shareholders decide to effect such an exchange,  they
shall  receive  shares  of  PRI  (DEL)  common  stock  possessing,   subject  to
differences  in applicable  law, the same general  rights as the common stock of
the Company.

     5. Approval,  Filing and Effective  Time. This Agreement and Plan of Merger
shall be  adopted  and  approved  by the  Company  and PRI  (DEL) in the  manner
required by the Delaware General  Corporation Law, as amended (the "DGCL"),  and
the New Jersey Business  Corporation  Act, as amended (the "NJBCA").  After this
Agreement  and Plan of Merger has been adopted and  approved,  and so long as it
has not been terminated pursuant to Section 6 hereof, the Company and PRI (DEL),



upon obtaining the requisite Company shareholder approval under the NJBCA, shall
file a  certificate  of merger with the  Secretary  of State of New Jersey and a
certificate  of ownership and merger with the Secretary of State of the State of
Delaware.  The Merger shall become effective upon the filing of such certificate
with the Secretary of State of Delaware (the "Effective Time").

     6. Amendment; Termination. This Agreement and Plan of Merger may be amended
or terminated at any time prior to the Effective  Time by action of the Board of
Directors of both the Company and PRI (DEL),  except as otherwise  prohibited by
the NJBCA or the DGCL,  notwithstanding the adoption or approval contemplated by
Section 5 hereof.

     7.  Further  Assurances.  From time to time,  as and when  required  by the
Surviving Corporation or its successors or assigns,  there shall be executed and
delivered on behalf of the Company such  documents  and other  instruments,  and
there  shall be taken or  caused  to be taken by it all such  further  and other
action,  as shall be  appropriate,  advisable  or  necessary  to:  (i) cause the
Surviving  Corporation to have its common stock  registered  with the Securities
and Exchange  Commission  under Section 12(b) of the Securities  Exchange Act of
1934,  as  amended,  and to have its common  stock  listed on the New York Stock
Exchange,  (ii)  vest,  perfect  or  confirm,  of  record or  otherwise,  in the
Surviving Corporation,  the title to and possession of all property,  interests,
assets, rights, privileges,  immunities, powers, franchises and authority of the
Company and (iii) otherwise carry out the purposes of this Agreement and Plan of
Merger.  The executive  officers and directors of the Surviving  Corporation are
fully authorized in the name and on behalf of the Company or otherwise,  to take
any and all such  action and to execute  and  deliver any and all such deeds and
other instruments.

     8. Service of Process;  Appointment  of Agent.  The  Surviving  Corporation
hereby  agrees  that it may be sued in the  State of New  Jersey  for any  prior
obligation  of the Company,  any prior  obligation  of any  constituent  foreign
corporation  qualified under Section  14A:13-4 of the NJBCA, and any obligations
hereafter  incurred  by the  Surviving  Corporation,  so long  as any  liability
remains  outstanding  against  the  Company in the State of New  Jersey,  and it
hereby irrevocably appoints the Secretary of State of New Jersey as its agent to
accept  service  of  process  in any  action  for the  enforcement  of any  such
obligation, including taxes.


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     IN WITNESS WHEREOF,  the Company and PRI (DEL) have executed this Agreement
and Plan of Merger as of the day and year first above written.

                                          PHARMACEUTICAL RESOURCES, INC.
                                           (A New Jersey corporation)

                                          By:    /s/ DENNIS J. O'CONNOR
                                                 ----------------------
                                          Name:  Dennis J. O'Connor
                                          Title: Vice President, CFO and
                                                 Secretary

                                          PHARMACEUTICAL RESOURCES, INC.
                                           (A Delaware corporation)

                                          By:    /s/ JOSEPH SCHOTT
                                                 -----------------
                                          Name:  Joseph Schott
                                          Title: Assistant Secretary


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