Use of Rituximab in Opsoclonus-Myoclonus in Children With Neuroblastoma

The purpose of this study is to evaluate the feasibility of giving four weekly doses of Rituximab (anti-CD20 antibody) in the treatment of children with refractory neuroblastoma associated opsoclonus-myoclonus. Patients must have continued symptoms of opsoclonus, myoclonus and or ataxia despite surgical resection and a minimum of one month of steroid therapy. Evaluations include clinical symptoms of opsoclonus-myoclonus and ataxia as well as detailed evaluation of learning and development.

Opsoclonus-myoclonus ataxia syndrome (OMS) is a rare immune mediated paraneoplastic syndrome that occurs in approximately 2 to 3% of children with neuroblastoma. Children with neuroblastoma associated opsoclonus-myoclonus tend to have a favorable prognosis from the standpoint of the cure of their cancer. Unfortunately,approximately two-thirds of this subgroup of patients are left with long term sequellae of the syndrome, including residual symptoms of opsoclonus, myoclonus, ataxia, learning difficulties and disturbance of sleep and mood. Multiple lines of evidence indicate an immune mechanism to this rare disorder. This includes occurence of OMS in the post-infectious state, aggressive lymphocytic infiltration of the tumor in children with OMS, and documented responses to therapries that act through suppression of the immune system. The current study utilizes four weekly doses of anti-CD 20 antibody (rituximab) to treat children with refractory OMS. Refractory disease is defined as continued symptoms of OMS despite surgical resection of the tumor and a minimum of one month of steroid therapy. All patients have baseline OMS evaluation and detailed neurocognitive testing with all studies being repeated at the completion of the four weekly infusions. OMS testing is repeated at Month 3. OMS testing and detailed neurocognitive testing is conducted at 6 months intervals until 2 years from the initial infusion. The goal of the study is to utilize this novel therapy to improve long term neurologic and neurodevelopmental outcome in children with refratory neuroblastoma associated opsoclonus-myoclonus.

To evaluate the feasibility of using 4 weekly Rituximab infusions in the treatment of children with neuroblastoma associated opsoclonus-myoclonus syndrome (OMS). The first infusion involved a slow up titration from an initial rate of 0.5 mg/kg/hour to a maximum of 400 mg/hour. If well tolerated, the subsequent infusions were administered at a starting rate of 1 mg/kg/hour to a maximum of 100 mg/hour for the first hour. In the absence of adverse reaction doses were escalated by 1 mg/kg/hour (maximum 100 mg increase per hour) every 30 minutes to a maximum rate of 400 mg/hour. If hypersensitivity or infusion related events occurred, the infusion was temporarily interrupted and resumed at 50% of the previous rate if reaction resolves. The number of participants for whom the study dosing was feasible is reported.

The trial was to be terminated early for any grade 3 or 4 toxicity that did not resolve in 2 of the first 5 patients treated, or for any infusion related death. The number of participants who experienced these events [grade 3 or 4 toxicity that did not resolve in 2 of the first 5 patients treated, or for any infusion related death] is reported.

OMS Evaluation Scale of Motor-Performance This scoring system utilizes a scale of 0 to 3, with 0 being unaffected by OMS, and 3 representing those with severe impairment. OMS testing will be scored by two independent scorers who have special expertise in the evaluation and management of children with neurologic disorders. The mean of these scores will be obtained, and a standard error of the mean reported.

Blood samples to be evaluated for the occurrence of antibody formation and potential effect on pharmacokinetic profiles.

B cell depletion was measured through analysis of serum IgG levels. The number of participants who experienced B cell depletion is reported.

Inclusion Criteria: Pathologic confirmation of diagnosis of neuroblastoma Surgical resection of primary tumor Symptoms of OMS despite a minimum of one month of steroid therapy Must meet all laboratory criteria to demonstrate adequate organ function - Exclusion Criteria: Patients currently receiving systemic chemotherapy for treatment of neuroblastoma Patients with documented active infection Patients who are HIV, Hep B or Hep C positive Organ toxicity from any prior therapy or surgical intervention must be resolved prior to study entry -