Two years of maintenance therapy with rituximab halves the risk of follicular lymphoma relapse compared with observation among patients with high tumor burden who had initial responses to standard immunochemotherapy regimens, investigators from the international PRIMA phase III study report. The progression-free survival rate among 505 patients randomized to maintenance with rituximab ( Rituxan in the United States, MabThera in Europe) was 82 percent at two years, compared with 66 percent for 513...