AMENDMENT TO EMPLOYMENT AGREEMENT


         THIS  AGREEMENT  is made as of April 1, 1999,  by and between  BioTime,
Inc. (the "Company"), and Harold Waitz (the "Employee").

                              W I T N E S S E T H:

         WHEREAS, Employee and the Company desire to amend Employee's Employment
Agreement dated June 1, 1996 ("Employment Agreement");

         NOW,   THEREFORE,   in   consideration  of  the  terms  and  conditions
hereinafter set forth, the parties hereto agree as follows:


         Section  5.1.1 of the  Employment  Agreement is amended to provide that
the Base  Salary  shall be One Hundred  Seventeen  Thousand  Dollars  ($117,000)
during the nine months  beginning  April 1, 1999;  and One  Hundred  Sixty-Three
Thousand Dollars ($163,000) during the calendar year beginning January 1, 2000.


         IN WITNESS WHEREOF,  the parties hereto have executed this Amendment to
Employment Agreement as of the day and year first above written.


                                          /s/Harold Waitz
EMPLOYEE:                           _______________________________
                                          Harold Waitz


COMPANY:                                  BIOTIME, INC.

                                         /s/Ronald S. Barkin
                                By: ___________________________
                                         Ronald S. Barkin,
                                         President

                                         /s/Judith Segall
                                By: ___________________________
                                         Judith Segall,
                                         Secretary