Treatment of aplastic anaemia by antilymphocyte globulin with and without allogeneic bone-marrow infusions.

29 patients with severe aplastic anaemia were treated with either antilymphocyte globulin (A.L.G.) alone (15 patients) or A.L.G. followed by infusion of allogeneic bone-marrow (14 patients). The overall response to both forms of treatment in terms of 1-year survival was 55%; 12 of the 29 patients showed a sustained haematological improvement, during a period of observation of up to 4 1/2 years. No potentially fatal complications were observed. None of the bone-marrow infusions led to a permanent "take" or graft-versus-host disease. How A.L.G. acts is unknown, but our findings accord with the hypothesis that, in a substantial proportion of cases of aplastic anaemia, unspecified autoimmune reactions block the development of residual stem cells A.L.G. seems to offer a good chance of survival, especially for those patients who do not have HLA-matched siblings. Its value should be further established.