The HLA system and the clinical response to treatment with chlorpromazine.

A group of 33 schizophrenic patients were typed for HLA-SD antigens and their qualitative clinical responses to chlorpromazine therapy determined. A highly significant positive correlation was found between response to chlorpromazine and HLA-AI positive, while HLA-A2 positive subjects showed a significant negative correlation to chlorpromazine treatment. In a second group of 17 patients the clinical response to chlorpromazine were evaluated quantitatively, by WPRS, in HLA-AI positive and HLA-AI negative patients. There were no pre-treatment differences in the scores. After treatment the scores of positive patients were significantly lower, indicating that they responded to a greater degree. Since the frequency of HLA-AI in hebephrenic patients is higher than that in other schizophrenics this may explain our earlier finding that hebephrenics, as a group, respond better to chlorpromazine than do other schizophrenics.