Treatment of aplastic anaemia with antilymphocyte globulin (ALG)

Clinical aspects of aplastic anemia

Severe aplastic anemia is a disorder characterized by peripheral pancytopenia and marrow hypoplasia. Although its pathophysiology is understood poorly, the majority of patients appear to have some immunologic destruction or suppression of hematopoietic cells. The only curative therapy to date is allogeneic stem cell transplantation, although the success of palliative immunosuppressive therapies has improved over the last two decades. Making the best therapy choice is complex and often requires balancing very divergent toxicity profiles, both acute and long-term.

Treatment of aplastic anemia with an investigational antilymphocyte serum prepared in rabbits

The authors evaluated antilymphocyte serum prepared in rabbits (ALS-R) as an alternative to antilymphocyte serum prepared in horses (ALG-H) in the therapy of aplastic anemia. Between 1980 and 1993, 57 evaluable patients received ALS-R and prednisone +/- cyclosporine +/- androgens. Standard response criteria were used and patients were evaluated at 3 months from the start of therapy. Median age was 43 years. Disease was present for up to 2 months in 24 patients, 2-5 months in 14 patients, and 6 months or more in 19 patients. Disease was severe in 30 patients and moderate in 27. Responses occurred in 16 (28%) of 57 patients. Responses were more frequent in females, in patients treated within 6 months of diagnosis, and in patients with severe disease. Among patients receiving ALS-R and cyclosporine within 2 months of diagnosis, 46% responded. After ALS-R therapy, 20 patients received ALG-H; 8 (40%) of 20 responded. Eight patients receiving ALS-R previously had received ALG-H; 2 (25%) of these 8 patients responded. Toxicity of ALS-R was minimal. Antilymphocyte serum prepared in rabbits, in conjunction with other immunosuppressive agents, represents an effective alternative to ALG-H in aplastic anemia, especially in patients previously treated with ALG-H.

Treatment of severe aplastic anemia with antilymphocyte globulin and androgens: a report on 33 patients

Thirty-three patients with severe aplastic anemia were treated with antilymphocyte globulin (ALG, Mérieux) and androgens (with or without corticosteroids) between 1981 and 1989; 24 patients (72.7%) were responders after one course of ALG, eight were nonresponders, and only one patient had an early death. Eighteen of the 24 responses occurred within 2 months of ALG treatment. Of note is the good response rate we obtained for very severe aplastic anemia (four responders of five evaluable patients). With a median follow-up of 36 months (range 1-97), a survival rate of 77.6% +/- 1.2% was obtained at 30 months. No predictive factor of survival could be identified except response to treatment (p = 0.0001). The duration of the disease before treatment was inversely related to survival, although this difference did not reach statistical significance (p = 0.06). Four initial responders relapsed after 14, 24, 38, and 57 months. Three of these patients received a second course of ALG and two responded. In contrast, four of the non-responders received a second course of ALG, with only one response. Toxicity of androgens was mild. No patient developed a PNH clone or myelodysplastic syndrome. Major toxicity of corticosteroids was femoral osteonecrosis in three patients. In our experience, the combination of ALG and androgens in SAA, with or without corticosteroids, was associated with a higher response rate and better survival than in many previously published reports. This could have been due to the intensive supportive care during the initial weeks of treatment. We suggest that it may also result from the addition of androgens to ALG, although this issue may only be resolved in a randomized study.

Patchy haemopoiesis in long-term remission of idiopathic aplastic anaemia

13 patients with idiopathic aplastic anaemia in remission for more than 2 years were examined to define the haemopoietic status by means of bone marrow scintigraphy, ferrokinetics and bone marrow culture for haemopoietic progenitor cells. Haemoglobin levels reached the normal range in all these patients although mild neutropenia and thrombocytopenia were still observed in 5 patients. Bone marrow scintigrams using indium-111 showed normal distribution in 2, diffuse low accumulation in 3, patchy distribution in 7, and expanded distribution with patchy uptake in 1 patient. The defective haemopoiesis was also confirmed by ferrokinetic and bone marrow culture studies. The patchy haemopoiesis appears to characterize the residual marrow damage in remission of idiopathic aplastic anaemia.

Successful treatment of severe refractory aplastic anemia with 3-beta etiocholanolone and nandrolone decanoate

A patient with aplastic anemia, who had been unresponsive to androgens, antithymocyte globulin, high-dose methylprednisolone, and cyclosporine, responded to treatment with 3-beta-etiocholanolone, nandrolone decanoate, and prednisolone acetate. Six months following initiation of therapy, she became red cell and platelet transfusion independent with neutrophils persistently over 1,000/microliters. A sustained partial remission has persisted for over 2 years. This observation suggests that a combined hematostimulatory approach may be of benefit, even in patients with long-standing refractory aplasia.

Immunomodulation therapy for severe aplastic anemia--ALG versus ALG plus cyclosporin A

Immunosuppressive treatment of aplastic anemia has been increasingly used as an alternative treatment to bone marrow transplantation. In this study, the additive effect of Cyclosporin A (CSA) (5mg/kg/day, at least 3 months) for maintenance of immunosuppression after antilymphocyte globulin (ALG) therapy (40mg/kg/day for 4 days) was compared to the previous ALG alone treatment (15mg/kg/day for 10 days). A high dose of methylprednisolone (20mg/kg/day for 5 days and 10mg/kg/day for 5 days) to the ALG group and a low dose of methylprednisolone (2mg/kg/day for 5 days) to the ALG plus CSA group were administered simultaneously. The results were as follows: 1) Sixteen (69.6%) out of twenty-three patients treated with ALG plus Cyclosporin A showed higher responses (CR: 48%, PR: 22%). On the contrary, nine out of nineteen in the ALG group showed lower responses (CR: 21%, PR: 26%). 2) Our data showed a tendency that male patients in age ranging from sixteen to thirty years showed an excellent response to ALG therapy (12/23: 52.2%). 3) The ALG plus CSA group revealed a faster response compared to the ALG alone group (15/16 within 6 months). 4) We speculate that ALG plus CSA therapy might be the treatment of choice for patients with a moderate degree of aplastic anemia. 5) Adding CSA to ALG increased the chance of infection, such as those with URI-like symptoms, but it did not affect the mortality rate. Our data suggest that the ALG plus CSA regimen may be a more useful therapeutic modality for patients with severe aplastic anemia who cannot be candidates for bone marrow transplantation and a randomized multicenter study is needed for confirmation of our preliminary study.

Zygomycosis in aplastic anaemia: response to a combined regimen of amphotericin B and antilymphocyte globulin

A 22-yr-old man with aplastic anaemia was treated with high dose methylprednisolone. A month later he developed severe epistaxis which was not controlled by regular platelet transfusions. A balloon catheter inserted into the left nostril caused necrosis of the left ala nasi accompanied by gross facial oedema. He received treatment with horse ALG for aplastic anaemia but developed gross facial oedema and anaesthesia of incisor and canine teeth on the right side. Radiographs initially showed thickening of the maxillary antral mucosa and later erosion of the maxilla over the anaesthetic region. A biopsy specimen of this region contained hyphae of zygomycetes. He was treated with amphotericin B and a second course of antilymphocyte globulin followed by oxymetholone. He has made a satisfactory clinical and haematological recovery.

Effect of androgens on the response to antithymocyte globulin in patients with aplastic anaemia

30 patients with aplastic anaemia (18/30 with severe aplastic anaemia) were prospectively randomized to be treated with 100 mg/kg ATG with or without the oral androgen Methenolone (3 mg/kg). 15 of 30 patients responded. Among the 15 patients receiving ATG plus androgen, 11 patients (73%) responded, including 8 complete and 3 partial responses. 4 of the 15 patients (31%) receiving ATG only responded, including 2 complete and 2 partial responses. The difference in response rate was statistically significant (p = 0.01). The survival rate in the total population of 30 patients was 64%. The survival rate in the group receiving ATG plus androgen was 87%; in the group receiving ATG only it was 43%. The difference in survival rates between both groups did not reach statistical significance (p = 0.15). Toxicity of ATG and androgens was considerable but manageable. These data support the result of the recent European reevaluation of a large pool of patients by the EBMT (39), that androgens in addition to ATG increase survival in patients with aplastic anaemia. They are, however, in contradiction to a controlled American study showing no benefit of a combined treatment with androgens as compared to ATG only. Further controlled studies on a larger number of patients are indicated to determine the therapeutic efficacy of androgens in addition to immunosuppression in aplastic anaemia.

No evidence for gamma-interferon mediated haematopoietic inhibition by T cells in aplastic anaemia: an observation in the course of immunosuppressive therapy

Two patients with aplastic anaemia were treated with immunosuppressive agents and peripheral blood T cells were cryopreserved serially. Inhibitory activity of T cells to autologous CFU-E, gamma-IFN production by T cells and T cell subpopulations were assayed after remission. Inhibitory activity to autologous CFU-E was not correlated with the numbers or ratios of T cell subpopulations. gamma-IFN production by T cells were within the normal range when inhibitory activity was found. In addition, gamma-IFN production increased after haematopoietic recovery. These findings suggest that gamma-IFN is not a soluble mediator of T cell-mediated haematopoietic inhibition in aplastic anaemia.

Refractory aplastic anemia: concomitant therapy with antithymocyte globulin and high-dose corticosteroids

Bone marrow transplantation is possible for only a minority of patients with severe aplastic anemia. There has been successful treatment in some patients with immunosuppressive agents: high-dose 6-methylprednisolone, antilymphocyte globulin, and antithymocyte globulin. We report the successful treatment of two patients with severe aplastic anemia with the simultaneous administration of antithymocyte globulin and high-dose 6-methylprednisolone after failure with antithymocyte globulin and low-dose corticosteroids.

Androstane therapy to treat aplastic anaemia in adults: an uncontrolled pilot study

During the past 9 years, 43 adult patients with severe aplastic anaemia have been treated with a combination of 3 alpha etiocholanolone and nandrolone decanoate in an uncontrolled pilot study. Eleven patients were considered acute and the remainder as chronic severe aplasia. 50% (22 patients) had a haematopoietic recovery and 40% have had a sustained remission varying from 1.5 to 8 years. Three patients who did not respond to 3 alpha etiocholanolone had a haematologic response when treated with the isomer 3 beta etiocholanolone. The recovery did not appear to be associated with age or duration of marrow aplasia. In view of the reproducible chemical structure of these androstanes, we believe this group of steroids should be evaluated further in the treatment of severe aplastic anaemia.

Cyclosporine A treatment in four cases of aplastic anemia

Cyclosporine A (CyA) treatment of 4 patients with severe aplastic anemia, who were ineligible for bone marrow transplantation, was carried out for periods of between 12 weeks to 20 months. A normalization of Hb and bone marrow, together with a marked improvement in WBC and platelet counts, were observed in only one of these four patients. The remission was maintained for 20 months under continuous treatment. A relapse occurred only when the patient himself interrupted treatment. No serious side effects were observed with CyA doses of 4-10 mg/kg/daily and blood concentrations of 200-400 ng/ml. No significant changes in T helper/T suppressor ratios were noted during the course of CyA treatment.

Aplastic anemia: analysis of two methods of treatment

Between 1981 and 1985, 27 patients with aplastic anemia have been treated by immunosuppression with antilymphocyte globulin and prednisolone or allogeneic bone marrow transplantation. Fifteen have undergone bone marrow transplantation and have an actuarial survival at 54 months of 65% +/- 12% (95% confidence limits). There have been four deaths from graft rejection, septicemia (two), and graft-versus-host disease. Twelve have received antilymphocyte globulin and have an actuarial survival at 56 months of 67% +/- 21%. Five of these now have a normal blood count and two have had good partial responses and are self supporting. Of the five non-responders, three survived, two with persistent aplasia and one after allogeneic bone marrow transplantation. Two are dead, one of hemorrhage and one after mismatched bone marrow transplantation. In this study antilymphocyte globulin produced survival equivalent to bone marrow transplantation although only 58% of patients had a response to the antilymphocyte globulin. The advantages and disadvantages of these two methods of treatment are discussed.

T cell-mediated inhibition of haematopoiesis in aplastic anaemia: serial assay of inhibitory activities of T cells to autologous CFU-E during immunosuppressive therapy

T cell-mediated inhibition of autologous erythroid colony formation was found in two patients with aplastic anaemia. Each patient was treated separately with ALG and methylprednisolone. Peripheral blood T cells were cryopreserved serially during the course of the disease. The inhibitory activity of T cells was assayed after remission using autologous bone marrow. The inhibitory activity of T cells was lost following the treatment and preceded haematopoietic recovery.

Severe aplastic anaemia following the use of hair dye: report of two cases and review of literature

We describe two female patients aged 31 and 62 y who developed severe aplastic anaemia following the use of hair dye containing para-toluenediamine. One received a bone marrow transplant but died after developing graft versus host disease and severe opportunistic infection. The second responded to treatment with methylprednisolone, oxymetholone and antithymocyte globulin and 3 y later she has a normal blood count apart from mild thrombocytopenia. In this paper we also review previously described case reports of aplastic anaemia apparently associated with the use of hair dye.

Cyclosporin A in the treatment of severe acute aplastic anaemia

Twelve consecutive adults with severe acute aplastic anaemia, not having a bone marrow transplantation option, were prospectively randomized to receive either cyclosporin A alone or an equivalent amount of this immunosuppressive agent in combination with antilymphocyte serum. The minimum follow-up is 36 months, with half the patients developing nephrotoxicity, which was easily reversible in all but one. No response could be attributed to either regimen. Cyclosporin A does not appear to have a place as primary form of treatment for adults with severe acute aplastic anaemia, either on its own or in combination with antilymphocyte serum.

Current considerations of the etiology of aplastic anemia

Aplastic anemia is a disorder characterized by marrow aplasia and pancytopenia. The pathogenetic mechanisms that lead to bone marrow aplasia have been intensively studied. Data obtained from these studies suggest that aplastic anemia is a heterogeneous disorder with regards to pathogenesis. Bone marrow aplasia may result from a number of abnormalities including qualitative or quantitative abnormalities of hematopoietic stem cells, abnormal interaction between bone marrow accessory cells (lymphocytes and macrophages) and hematopoietic stem cells, cytotoxic humoral inhibitors of hematopoiesis, and abnormalities of the bone marrow microenvironment. A number of new therapeutic options have improved the survival of patients with aplastic anemia. Allogeneic bone marrow transplantation has actually resulted in the cure of patients. Unfortunately, only a minority of patients have a suitable bone marrow donor and alternate modes of therapy have been sought. Encouraging results have been reported from several centers concerning the use of antilymphocyte serum in patients with aplastic anemia. Certainty of the ultimate long-term benefit of this type of immunosuppressive therapy is not possible until careful, randomized, prospective studies of its use are completed.

Comparison between bone marrow transplantation and antithymocyte globulin in treatment of young patients with severe aplastic anemia

Fifty-seven patients younger than 25 years with severe aplastic anemia underwent either bone marrow transplantation or antithymocyte globulin therapy (ATG) to ascertain which approach should be used in young patients. Thirty-five patients who had an HLA-identical sibling donor underwent bone marrow transplantation after conditioning with cyclophosphamide and low-dose total-body radiation. Twenty-two patients who did not have an HLA-identical donor received ATG. The 2-year actuarial survival of patients after transplant is 72% (95%, CI 64% to 80%), versus 45% (95%, CI 29% to 61%) in those given ATG therapy (P = 0.18). In those patients surviving 6 months after treatment, return of peripheral blood counts to normal values was more common in patients who received marrow transplant compared with those given ATG therapy (P less than 0.001). Furthermore, 24 of 26 transplant survivors had Karnofsky performance scores greater than 90%, compared with only five of 13 ATG survivors. These data suggest that bone marrow transplantation is the preferred therapy for severe aplastic anemia in young patients who have an HLA-identical sibling donor. ATG should be reversed for those young patients with severe aplastic anemia who do not have a histocompatible marrow donor.