Erwinia carotovora asparaginase in patients with prior anaphylaxis to asparaginase from E. coli.

Abstract

Asparaginase prepared from Erwinia carotovora was well tolerated when given to four patients with acute lymphocytic leukemia who previously had had anaphylactic reactions from E. coli asparaginase. The Erwinia enzyme was cleared from plasma with a half life of 7 to 13 hours, a time similar to some preparations of E. coli asparaginase in patients who had not sustained anaphylaxis. Serum asparagine levels decreased to unmeasurable levels after Erwinia asparaginase in a manner reminiscent of the E. coli enzyme. No positive precipitin reaction or skin test to either E. coli or Erwinia enzyme was detected. These results indicate that there is no great degree of immunologic cross reaction to prevent the use of the Erwinia enzyme in patients who sustained anaphylaxis to the E. coli preparation. The availability of a second active asparaginase from a different microbiological source extends the usefulness of asparaginase in clinical therapy. Stabilization and protective effect of Erwinia enzyme activity by human plasma was demonstrated.