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

The role of androgen therapy in acquired aplastic anemia and other bone marrow failure syndromes

Bone marrow failure syndromes are a heterogeneous group of diseases. With the major advancements in diagnostic tools and sequencing techniques, these diseases may be better classified and therapies may be further tailored. Androgens, a historic group of drugs, were found to stimulate hematopoiesis by enhancing the responsiveness of progenitors. These agents have been used for decades to treat different forms of bone marrow failure. With the availability of more effective pathways to treat BMF, androgens are less used currently. Nevertheless, this group of drugs may serve BMF patients where standard therapy is contraindicated or not available. In this article, we review the published literature addressing the use of androgens in BMF patients and we make recommendations on how to best use this class of drugs within the current therapeutic landscape.

Androgens and erythropoiesis: past and present

Association between androgens and erythropoiesis has been known for more than seven decades. Androgens stimulate hematopoietic system by various mechanisms. These include stimulation of erythropoietin release, increasing bone marrow activity and iron incorporation into the red cells. Before the discovery of recombinant erythropoietin (rhEpo), androgens were used in the treatment of anemia associated with renal disease, bone marrow suppression, and hypopituitarism. Anabolism is an additional advantage of androgen therapy. Furthermore, in light of recent reports regarding adverse effects of rhEpo, the role of androgen therapy in various types of anemias should be readdressed. Polycythemia remains a known side effect of androgen therapy. In this review, we will briefly discuss the initial animal and human studies which demonstrated the role of androgens in the treatment of anemia, their mechanism of action, a detailed account of the efficacy of androgens in the treatment of various anemias, the erythropoietic side effects of androgens and finally, the relationship between hematocrit levels and cardiovascular disease.

Long-term outcome in acquired aplastic anemia treated with an intensified dose schedule of horse antilymphocyte globulin in combination with androgens

Aplastic anemia (AA) is a rare hematopoietic stem cell disease, which can be treated with horse antilymphocyte globulin (ALG) for patients not eligible for bone marrow transplantation. ALG gives about 60% overall survival rate (OS) after 5 years, a 30% of persistent complete remission and a 20% early death rate related to failure. ALG has been incriminated in the emergence of 10 to 20% therapy-related AML/MDS (t-AML/MDS) with the usual doses. Questions remain whether higher doses of ALG could improve the response and OS rates and whether the combination with androgens is able to protect patients from t-AML/MDS. We have carried out a single institutional retrospective study of 87 AA treated with higher doses of ALG, twice the usual posology (140 mg/kg instead of 75 mg/kg), combined to androgens. The overall response rate was 77% and the OS rate at 5 years was 78%. Androgens in combination with ALG improved response and OS rates. At diagnosis, 6% of AA had an abnormal karyotype using conventional cytogenetic not related to any time-to-event. Two patients displayed a cytogenetic conversion related to the occurrence of secondary malignancies. The incidence of t-AML/MDS was 2.3% with an estimated 10-year cumulative incidence of 3.1. Our results show that higher doses of ALG combined to androgens are feasible and give results close to those recently describe with the immunosuppressive treatments including ALG associated to cyclosporine, with a low SMD/AML incidence rate.

Diagnosis and treatment of children with aplastic anemia

BACKGROUND

Long-term survival rates among children diagnosed with severe aplastic anemia (SAA) are excellent due to the success of human leukocyte antigen (HLA)-identical related hematopoietic stem cell transplantation (HSCT), concurrent advances in immunosuppressive treatment (IST), and improved supportive care. The challenge in making treatment recommendations for children with SAA, therefore, is to balance the apparent chronicity and morbidity following IST, with the potential up-front toxicity and complications of HSCT.

METHODS

This review provides an update on the diagnosis and a risk-based treatment algorithm for children with acquired SAA. Recent experience using alternative donor HSCT and efforts to extend HSCT eligibility through advances in donor matching, de-escalation of conditioning regimens, and potential marrow graft engineering are highlighted. We discuss IST response rates, risks of relapse, and complications including clonal evolution.

CONCLUSIONS

While good treatment options exist for a majority of children diagnosed with SAA, novel non-transplantation treatments for unresponsive and relapsed patients without suitable transplant donors are needed. Further improvements in outcome will ultimately require a more complete understanding of the pathophysiology of aplastic anemia (AA).

Lack of known hepatitis virus in hepatitis-associated aplastic anemia and outcome after bone marrow transplantation

Viral infection has been shown to induce aplastic anemia, unidentified types of hepatitis being the most common cause for aplastic anemia-associated viral hepatitis. The survival rate for this group of patients after bone marrow transplantation with stem cells from an HLA-matched sibling is not well known. The aim of this study was to determine the prevalence of hepatitis G virus (HGV) and transfusion transmitted virus (TTV) infection in non-A, non-B, non-C hepatitis associated-aplastic anemia (HAAA) patients, and to define the role of bone marrow transplantation (BMT) as a therapeutic modality for this disease. Sixty-eight patients (43 males and 25 females) with aplastic anemia, underwent allogeneic BMT at the Hadassah University Hospital between 1981 and 1997. Onset of hepatitis was defined as jaundice and elevated alanine aminotransaminase (ALT) levels. Onset of aplastic anemia was defined as the first date on which varying degrees of pancytopenia occurred: hemoglobin level below 10 g/dl, WBC below 2 x 10(9)/l and low platelet count 10 x 10(10)/l. Serial serum samples from HAAA patients were assayed for virological and/or serological markers of hepatitis A, B, C, D, E, G viruses, TTV and parvovirus B19. Seventeen of the 68 patients with aplastic anemia (25%) suffered from hepatitis, 12 males and five females, ages 5 to 36 years. The mean interval between onset of hepatitis and first indication of aplastic anemia was 62 days (range 14-225 days). The development of aplastic anemia was unrelated to age, sex or severity of hepatitis. Ten of the 17 patients (59%) achieved complete ALT recovery prior to the diagnosis of aplastic anemia. Serum samples were available for 15 patients; none had evidence of acute or active hepatitis A, B, C, D, E, G and TTV virus infection at the time of diagnosis. Parvovirus B19 DNA sequences were not detectable in 10 of 12 tested cases; two positive results were detected in serum samples obtained after blood transfusion, making the analysis of these positive results difficult. All 17 patients underwent BMT. The mean post-BMT follow-up period was 38 months (range 1 day-123 months), five patients (30%) died 1 to 160 days post BMT, and 12 (70%) are alive 31 to 123 months after BMT. Relapsing hepatitis was not observed in any of the patients. In conclusion, HAAA is a disease of the young and the etiologic agent associated with HAAA remains unknown. HGV, TTV and parvovirus B19 sequences were not detected in any of the HAAA cases. The survival rate after BMT with stem cells from an HLA-matched sibling is similar to that for patients with non-hepatitis-associated aplastic anemia.

Immunosuppressive treatment of aplastic anemia with antithymocyte globulin and cyclosporine

Immunosuppression is the treatment modality for the majority of patients with aplastic anemia, most of whom are not candidates for allogeneic stem-cell transplantation. Antithymocyte globulin (ATG) or antilymphocyte globulin (ALG) have proven to be essential components of all regimens. Initial response rates can be improved by the addition of cyclosporine A (CsA), and this combination has become the standard of care for appropriate patients. Several new approaches to immunosuppression are being studied, including the optimal timing of administration of these drugs, the use of novel immunosuppressive agents, and the addition of early- and late-acting hematopoietic growth factors.

Treatment of aplastic anaemia (AA) with antilymphocyte globulin (ALG) and methylprednisolone (MPred) with or without androgens: a randomized trial from the EBMT SAA working party

134 patients with acquired aplastic anaemia (AA) were given HALG 15 mg/kg/d for 5 d and methylprednisolone for 1 month, and randomized to receive (n = 69) or not (n = 65) oxymetholone 2 mg/kg/d p.o. daily for 4 months. Early mortality (< 120 d) was comparable in the two arms 12/69 (17%) and 11/65 (17%), and correlated with the severity of the disease (39%, 10% and 6% respectively in patients with neutrophil counts (PMN) < 0.2, 0.2-0.5, > 0.5 x 10(9)/l). The response rate at 120 d was significantly greater in patients receiving androgens (56% v 40%; P = 0.04); it was 68% v 48% (P = 0.02) in patients surviving 120 d, and 78% v 27% (P = 0.03) in females with PMN less than 0.5 x 10(9)/l. In a multivariate Cox analysis on patients with less than 0.5 x 10(9)/l PMN, the probability of responding without androgens was reduced compared to the androgen treatment arm (P = 0.05). Survival was comparable in the two groups (71% v 65%). It was superior (74% v 50%), but not significantly (P = 0.1) in females with PMN < or = 0.5 x 10(9)/l receiving androgens. Side-effects, including biochemical abnormalities and virilization, could be controlled and were reversible. In conclusion, the addition of androgens to HALG and methylprednisolone as first line treatment of aplastic anaemia significantly improves the response rate at 4 months, particularly in females with low neutrophil counts, although there is no significant effect on short-term survival. The reversible side-effects warrant the use of androgens as an adjunct to the first course of ALG in females with severe AA.

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.