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                                                                     Exhibit 4.1



                           AMENDMENT TO LOAN AGREEMENT


         Reference is made to: (i) the Loan Agreement dated as of June 22, 2001
(the "Loan Agreement") between Pilot Therapeutics, Inc., a North Carolina
corporation ("Pilot"), and PharmaBio Development Inc., a North Carolina
corporation ("PharmaBio"); (ii) Pilot Therapeutics Holdings, Inc., a Delaware
corporation and owner of all of the capital stock of Pilot ("Holdings"); (iii)
the transaction completed on August 24, 2001 whereby Interallied Group, Inc., a
Nevada corporation and the predecessor of Holdings ("Interallied"), acquired all
of the capital stock of Pilot (the "Acquisition Transaction"); and (iv) the
transaction on October 2, 2001 whereby Interallied reincorporated from Nevada to
Delaware by merger into Holdings (the "Reincorporation Transaction").

         For good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties agree as follows:

         1. Section 2.07(c) of the Loan Agreement is hereby amended to: delete
the reference to $5.00 in Section 2.07(c)(i)(x) and insert $2.50 in lieu
thereof; and delete the reference to $3.83 in Section 2.07(c)(ii) and insert
$1.915 in lieu thereof. Notwithstanding the foregoing, the Conversion Price (as
defined in the Loan Agreement) is subject to adjustment from time to time as
provided in the Loan Agreement.

         2. Pursuant to Section 2.07(c)(iii), and in connection with the
Acquisition Transaction and the Reincorporation Transaction, the conversion and
purchase rights of PharmaBio under the Loan Agreement have become conversion and
purchase rights with respect to the common stock of Holdings.

         3. This Amendment is limited as specified and shall not constitute a
modification, acceptance or waiver of any other provisions of the Loan Agreement
or any of the other Loan Documents (as defined in the Loan Agreement). This
Amendment may be executed in one or more counterparts, each of which shall be
deemed to be an original and all of which, when taken together, shall constitute
one and the same instrument. This Amendment may be executed and


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delivered by facsimile or telecopy and any execution by such means shall be
deemed to be an original.

         IN WITNESS WHEREOF, the parties have duly executed this Amendment as of
December 21, 2001.


                                PHARMABIO DEVELOPMENT INC.

                                By: /s/ Tom Perkins
                                    --------------------------------------------
                                    Name: Tom Perkins
                                    Title: VP and General Counsel


                                PILOT THERAPEUTICS, INC.

                                By: /s/ Floyd H. Chilton
                                    --------------------------------------------
                                    Name: Floyd H. Chilton
                                    Title: President and Chief Executive Officer


                                PILOT THERAPEUTICS HOLDINGS, INC.


                                By: /s/ Floyd H. Chilton
                                    --------------------------------------------
                                    Name: Floyd H. Chilton
                                    Title: President and Chief Executive Officer