TI   "Urgency Spurs AIDS Vaccine Testing"
 AU   Signor, Roger
 SO   St. Louis Post-Dispatch (12/27/93) P. 1B
 AB   The urgency of testing new AIDS vaccines has heightened in recent
      months, primarily due to obstacles facing the first generation of
      candidate vaccines.  After five years of preliminary trials,
      laboratories are finding that the vaccines are safe, but may be
      ineffective.  The problem is that the vaccines are failing a final
      lab test that they must undergo before they can be used in large
      trials.  In this test, the vaccine is mixed in a test tube with
      viruses taken from AIDS patients, as well as cells that can make
      antibodies to kill the virus at a cue from the vaccine.  The failure
      of a vaccine to kill the "wild" viruses is a warning to researchers
      that it may be ineffective.  Scientists are checking to determine
      whether the test or the vaccine is flawed.  A conclusion that the
      vaccines are ineffective could jeopardize a large, $10-million
      nationwide field trial of the first-generation vaccines by the
      National Institutes of Health.  While some AIDS authorities say that
      the first generation of vaccines still may work, others believe that
      throwing out the vaccines and starting over may be best.  "The virus
      strain used to make the first generation of vaccines is probably not
      the major strain of virus now involved in infecting people," said Dr.
      William G. Powderly, director of the AIDS Clinical Trial Unit at
      Washington University's School of Medicine.  "If you want to prevent
      AIDS you have to hit the virus that's predominant in the early stages
      of infection."  Dr. Margaret Johnston, director of the division of
      AIDS research at NIH says that, after more tests, her agency will
      decide whether or not to abandon the trial.

      Copyright (c) 1993 - Information, Inc., Bethesda, MD.  This
      information is provided by the Centers for Disease Control &
      Prevention (CDC), National AIDS Clearinghouse as a public service. 
      Non-profit reproduction is encouraged.

 * Origin: AEGIS/San Juan Capistrano 714.248.2836 (CASAN)  (1:103/927)
 * Provided as a service of THE BACKROOM - NYC * 718-951-8256