Genentech and Biogen Idec Announce Positive Results From a Phase II Trial of Rituxan in Relapsing-Remitting Multiple Sclerosis
August 28 -- PRNewswire-FirstCall -- Genentech and Biogen Idec announced today that a Phase II study of Rituxan (Rituximab) for relapsing-remitting multiple sclerosis (RRMS) met its primary endpoint. The study of 104 patients showed a statistically significant reduction in the total number of gadolinium enhancing T1 lesions observed on serial MRI scans of the brain at weeks 12, 16, 20 and 24 in the Rituxan-treated group compared to placebo. Genentech and Biogen Idec will continue to analyze the study results and will submit the data for presentation at an upcoming medical meeting.
"These initial results exceeded our expectations," said Hal Barron, M.D., Genentech senior vice president, development and chief medical officer. "Showing a significant benefit at 24 weeks in this small Phase II trial supports our hypothesis that selective B-cell targeted therapy may play an important role in the treatment of MS."
"Biogen Idec is committed to offering multiple options for people living with MS, a devastating disease. We are very encouraged by these data and look forward to learning more about the potential of Rituxan as a therapy to treat MS," said Alfred Sandrock, M.D., Ph.D., senior vice president, neurology research and development, Biogen Idec.
Rates of overall adverse events and serious adverse events were comparable between the two treatment groups. Serious infectious adverse events occurring in Rituxan-treated patients included gastroenteritis and bronchitis. The overall rates of infection were comparable among the two treatment groups with an increase in the rates of nasopharyngitis, upper respiratory tract infections, urinary tract infections and sinusitis in the Rituxan-treated patients. There were more first infusion-related reactions with Rituxan, the majority of which were mild to moderate and were generally reversible with medical intervention. The companies continue to monitor the long-term safety of Rituxan treatment.
About the Study
This Phase II randomized, double-blind, parallel-group, placebo-controlled, multi-center study was designed to evaluate safety and efficacy of Rituxan in adults with RRMS. A total of 104 patients at 48 sites in the U.S. and Canada were randomized to receive either a single treatment course of Rituxan or placebo. Gadolinium-enhancing lesions visible by MRI scans were assessed at 12, 16, 20 and 24 weeks. Patients will continue to be followed for 48 weeks.
Rituxan Safety Profile in Oncology and Autoimmune Diseases
The safety profile of Rituxan has been established in more than 960,000 patient exposures over a period of eight years.
In general, the adverse events observed in patients with RA, an autoimmune disease, were similar in type to those seen in patients with non-Hodgkin's lymphoma (NHL). The most common adverse events observed in patients treated with Rituxan for RA in clinical trials were infusion reactions and infections. No significant change in average immunoglobulin levels was observed in Rituxan-treated patients in clinical trials. There was no increase in hematologic malignancies, demyelinating events or risk of opportunistic infections (including tuberculosis) in Rituxan-treated patients over 24 weeks of treatment. Although 5 percent of Rituxan-treated patients developed human anti-chimeric antibodies (HACA), this was not associated with loss of clinical response or additional safety observations.
The majority of patients experience infusion-related symptoms with their first Rituxan infusion. These symptoms include but are not limited to: flu-like illness, fever, chills/rigors, nausea, urticaria, headache, bronchospasm, angioedema, hypotension and hypoxia. These symptoms vary in severity and generally are reversible with medical intervention.
Severe infusion reactions have been reported in patients treated with Rituxan, some with fatal outcomes in patients with NHL. These severe reactions typically occur during the first infusion. The most severe manifestations and sequelae include pulmonary infiltrates, acute respiratory distress syndrome, myocardial infarction, ventricular fibrillation, cardiogenic shock, and anaphylactic and anaphylactoid events. Patients who develop clinically significant infusion reactions should have their Rituxan infusion discontinued and receive medical treatment. Acute renal failure requiring dialysis with instances of fatal outcome has been reported in the setting of tumor lysis syndrome following treatment with Rituxan. Severe mucocutaneous skin reactions, some with fatal outcome, have been reported in association with Rituxan treatment. Patients experiencing a severe mucocutaneous reaction should not receive any further infusions and seek prompt medical evaluation. Abdominal pain, bowel obstruction and perforation, in some cases leading to death, were observed in patients receiving Rituxan in combination with chemotherapy for diffuse large B-cell (DLBCL), CD20-positive, non-Hodgkin's lymphoma. Other serious or potentially life-threatening adverse reactions that have been reported following Rituxan therapy include Hepatitis B reactivation with fulminant hepatitis, other viral infections, hypersensitivity reactions, and cardiac arrhythmias.
Rituxan is a therapeutic antibody that targets and selectively depletes CD20-positive B-cells without targeting stem cells or existing plasma cells. In addition to RRMS, Rituxan is being studied in primary progressive MS, for which there is currently no FDA-approved therapy. Rituxan is being studied in other autoimmune diseases with significant unmet medical needs, including systemic lupus erythematosus, lupus nephritis and ANCA-associated vasculitis.
Rituxan, discovered by Biogen Idec, first received FDA approval in November 1997 for the treatment of relapsed or refractory, low-grade or follicular, CD20-positive, B-cell non-Hodgkin's lymphoma. It was also approved in the European Union under the trade name MabThera® in June 1998. In addition, Rituxan received FDA approval in February 2006 for the treatment of diffuse large B-cell lymphoma (DLBCL) in combination with CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or other anthracycline-based chemotherapy regimens in previously untreated patients, as well as in combination with methotrexate to reduce signs and symptoms in adult patients with moderately-to-severely active rheumatoid arthritis who have had an inadequate response to one or more tumor necrosis factor antagonist therapies.