Exhibit 10.1
                                  ------------


                               AMENDMENT NO. 2 TO

                          AGREEMENT AND PLAN OF MERGER
                          ----------------------------


     THIS AMENDMENT NO. 2 TO AGREEMENT AND PLAN OF MERGER (this  "Amendment") is
made as of this 21st day of November,  2002, among Bioanalytical  Systems, Inc.,
an Indiana  corporation  ("BAS"),  PI Acquisition Corp., a Maryland  corporation
("MergerCo"), and PharmaKinetics Laboratories, Inc., a Maryland corporation (the
"Company").  All  capitalized  terms used but not defined  herein shall have the
meanings assigned to such terms in the Merger Agreement (as defined below).

     WHEREAS,  BAS,  MergerCo  and the  Company  are  parties  to  that  certain
Agreement  and Plan of Merger dated as of June 20, 2002, as amended by Amendment
No. 1 to  Agreement  and Plan of Merger  dated as of July 24, 2002 (the  "Merger
Agreement"); and

     WHEREAS,  BAS, MergerCo and the Company desire to amend certain portions of
the Merger Agreement pursuant to the terms and conditions of this Amendment;

     NOW, THEREFORE, in consideration of the mutual agreements herein contained,
and pursuant to Section 10.11 of the Merger  Agreement,  the Merger Agreement is
hereby amended by the parties as follows:

     1. The "Index of Defined  Terms" of the Merger  Agreement is hereby amended
by adding the following after the term "PKLB Common":

            "PKLB Note                          ss.9.1(d)(v)"

     2. Exhibit 2.3 is hereby  amended and restated in its entirety as set forth
on Exhibit 2.3 hereto.

     3. Section A. of the  Background  Information  is hereby  amended by adding
",other than  Parent,"  after "(x) the holders" and before "of common" in clause
(x) of the second  sentence  and the last  sentence  is hereby  restated  in its
entirety as follows "The holders of shares of PKLB Common  (other than  Parent),
Class A Preferred and Class B Preferred are sometimes  hereinafter  collectively
referred to as the 'Shareholders'.".

     4. Section 2.2 is hereby amended and restated in its entirety as follows:

     ss.2.2  Conversion of PKLB Common.  At the Effective Time, by virtue of the
Merger  and  without  any  action on the part of  MergerCo,  the  Company or the
holders of any shares of PKLB Common:

          (a) Subject to the other provisions of this Section 2.2 and to Section
     3.1(k) and (l),  other than  shares of PKLB  Common  held by Parent  (which
     shall be treated as set forth in Section 2.2(c)), each share of PKLB Common
     issued and  outstanding  immediately  prior to the Effective  Time shall be
     converted  into the  right to  receive  one-twelfth  (1/12) of one share of
     Parent Common,  upon surrender of the Common Certificate (as defined below)
     representing such shares of PKLB Common.



<PAGE>


          (b) All such  shares of PKLB  Common,  when  converted  as provided in
     Section  2.2(a),  shall no  longer  be  considered  outstanding  and  shall
     automatically  be canceled  and retired and shall cease to exist,  and each
     Common  Certificate  previously  evidencing  such shares  shall  thereafter
     represent  only the right to receive the number of shares of Parent  Common
     set forth in Section 2.2(a). The holders of Common Certificates (as defined
     below) previously evidencing shares of PKLB Common outstanding  immediately
     prior to the Effective  Time shall cease to have any rights with respect to
     the PKLB Common,  except as otherwise  provided herein or by law, and, upon
     the surrender of Common  Certificates in accordance with Section 3.1, shall
     only have the right to receive  for their  shares of PKLB Common the number
     of shares of Parent  Common as set forth in  Section  2.2(a),  without  any
     interest thereon.

          (c) The parties  acknowledge that Parent may own shares of PKLB Common
     at the Effective  Time and they hereby agree that, in such event,  any such
     shares of PKLB Common held by Parent shall,  as of the  Effective  Time, no
     longer be considered  outstanding and shall  automatically  be canceled and
     retired and shall  cease to exist and shall not  entitle  Parent to receive
     Parent Common or other Merger Consideration. Parent shall not be considered
     to be a  "Shareholder"  of the  Company  as  that  term  is  used  in  this
     Agreement.

     5.  Section  2.3(a) is hereby  amended by deleting  the phrase "Six Dollars
($6.00)" and replacing it with "Four Dollars and Eighty Cents ($4.80)".

     6. Section  9.1(b)(iii) is hereby amended by deleting the phrase  "December
31, 2002" and replacing it with "March 31, 2003".

     7. Section 9.1(d) is hereby amended as follows:

          a.   The "." is deleted  from the end of  subsection  (iii) and ";" is
               added in its place.

          b.   A new section (iv) is added as follows:

          "(iv) if any holder of Class A Preferred has delivered  written notice
     to  the  Company  that  such  holder  intends  to  exercise  or is  thereby
     exercising its right to convert all or any portion of the Class A Preferred
     held by such holder into PKLB Common; or"

          c.   A new section (v) is added as follows:

          "(v) if the registered owners of 100% of the Class B Preferred fail to
     deliver  written  notice to the Company as described  in paragraph  5(b) of
     that certain Secured Convertible Revolving Note (the "PKLB Note") issued by
     the Company to Parent dated as of November 14, 2002,  prior to such time as
     Parent may elect to exercise the Conversion  Rights (as defined in the PKLB
     Note) granted to it in the PKLB Note."

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     IN WITNESS  WHEREOF,  the  undersigned  have  caused this  Amendment  to be
executed by their duly authorized officers as of the date first above written.

                              BIOANALYTICAL SYSTEMS, INC.



                              By /s/ Peter T. Kissinger
                                 -----------------------------------------------
                                     Peter T. Kissinger, Ph.D.
                                     Chief Executive Officer


                              PI ACQUISITION CORP.



                              By /s/ Peter T. Kissinger
                                 -----------------------------------------------
                                     Peter T. Kissinger, Ph.D.
                                     Director


                              PHARMAKINETICS LABORATORIES, INC.



                              By /s/ James M. Wilkinson
                                 ----------------------------------------------
                                     James M. Wilkinson, II, Ph.D.
                                       President and Chief Executive Officer



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