The present invention relates to stable formulations of Neisseria meningitis rLP2086 Subfamily B Antigens in immunogenic compositions. The present invention also relates to methods of preserving the conformation of Neisseria meningitis rLP2086 Antigens and methods for determining the potency of Neisseria meningitis rLP2086 antigens.本發明關於腦膜炎奈瑟菌(Neisseria meningitidis)rLP2086亞族B抗原的致免疫組成物之安定調製劑類。本發明亦關於保存腦膜炎奈瑟菌rLP2086抗原之構形的方法及用於測定腦膜炎奈瑟菌rLP2086抗原之效力的方法。