Rituximab for the treatment of childhood chronic idiopathic thrombocytopenic purpura and hemophilia with inhibitors

Treatment of an infant with severe acute refractory immune thrombocytopenic purpura using combination therapy including rituximab

Some infants with acute immune thrombocytopenic purpura (ITP) do not respond to first-line therapy, and currently there is no consensus on therapy for these refractory cases. We describe a 12-week-old infant with acute ITP who was unresponsive to intravenous immunoglobulin and corticosteroid, and developed gastrointestinal bleeding. Several combination therapies were unsuccessful. After four doses of rituximab followed by intravenous immunoglobulin and corticosteroid, his platelet counts gradually increased. Combined therapy which includes rituximab may be a promising treatment for severe acute refractory ITP.

B-cell depletion for autoimmune thrombocytopenia and autoimmune hemolytic anemia in pediatric systemic lupus erythematosus

OBJECTIVES

Our goal was to determine long-term efficacy and safety of B-cell-depletion therapy for children with autoimmune thrombocytopenia and autoimmune hemolytic anemia in pediatric systemic lupus erythematosus.

PATIENTS AND METHODS

A retrospective, single-center cohort study was conducted including all patients with pediatric systemic lupus erythematosus who were diagnosed with autoimmune thrombocytopenia and/or autoimmune hemolytic anemia and treated with rituximab. Treatment efficacy and safety parameters were monitored and recorded.

RESULTS

Nine patients with pediatric systemic lupus erythematosus were included in the study: 5 had autoimmune thrombocytopenia, 3 had autoimmune hemolytic anemia, and 1 had both. There were 5 female and 4 male patients; median age at diagnosis of pediatric systemic lupus erythematosus was 14 years (range: 8-16 years); and median pediatric systemic lupus erythematosus disease duration to time of rituximab treatment was 6 months (range: 2-30 months). Complete response was achieved in all 6 children with autoimmune thrombocytopenia (median time to complete response: 2 weeks [range: 1-12 weeks]). Two patients' conditions flared at 48 and 68 weeks, respectively, and were re-treated. The remaining 4 patients continued to be in remission at 24, 32, 36, and 88 weeks, respectively. All 4 children with autoimmune hemolytic anemia achieved complete response at a median time of 4 weeks (range: 4-32 weeks). All patients remained in complete response at 24, 44, 84, and 100 weeks of follow-up. Complete B-cell depletion was seen in all children after rituximab treatment. No serious infections occurred, but 1 patient had an infusion reaction.

CONCLUSIONS

Preliminary evidence suggests that B-cell-depletion therapy with rituximab is an efficacious and safe treatment for autoimmune thrombocytopenia and autoimmune hemolytic anemia in pediatric systemic lupus erythematosus. Despite the prolonged effect on B-cell numbers and function, no serious infections were observed.

Immune thrombocytopenic purpura

Immune thrombocytopenic purpura (ITP) is the commonest cause of sudden onset thrombocytopenia in a healthy child. The condition is frequently preceded by a viral infection. The hematological parameters are essentially normal except a low platelet count. Bone marrow examination is not routinely indicated except in specific situations. The pros and cons of drug treatment have been discussed as the disease is benign with excellent prognosis in majority of the cases. The various treatment options including low and high dose steroids, intravenous immunoglobulins and anti D have been discussed at length with other modalities of treatment and role of splenectomy. Current therapeutic options with rituximab and other drugs for stimulating platelet production in chronic cases have also been included in discussion.

The efficacy of rituximab in high-grade pediatric B-cell lymphoma/leukemia: a review of available evidence

PURPOSE OF REVIEW

This review evaluates whether rituximab has efficacy in high-grade pediatric B-cell lymphoma/leukemia. Current pediatric protocols for CD20+ B-cell lymphoma/leukemia significantly improve survival, but with major morbidity. To assess whether rituximab has efficacy in very high-grade pediatric disease, all published data on rituximab therapy for Burkitt's lymphoma/B acute lymphoblastic leukaemia (B-ALL) and pediatric patients with relapsed/refractory large B-cell lymphoma were reviewed.

RECENT FINDINGS

Three trials in adult Burkitt's/B-ALL showed a significant survival advantage when rituximab was added to standard chemotherapy. Minimal pediatric data have been published, but 19 children with mature B-cell lymphoma/B-ALL received rituximab, alone or in combination with chemotherapy, as salvage therapy, after failure of intensive chemotherapy. Fifteen of 19 (79%) responded, 12 (63%) remained alive in continuous complete remission at 5+ to 48+ months of follow-up. Two patients were alive in partial remission. Five patients died, four of progressive disease. Only one patient had no response to rituximab.

SUMMARY

Rituximab has demonstrated efficacy in Burkitt's disease in adults. Although positive reporting bias is suspected, it appears that rituximab, even as monotherapy, has efficacy in heavily pretreated pediatric patients with high-grade B-lymphoma/B-ALL. Rituximab use can be justified in a prospective controlled chemotherapy dose-reduction study.