What is the fine-grained topic of the following text: "Primary HLH is a rare and life-threatening condition typically affecting children and this approval fills an unmet medical need for these patients," commented Dr Richard Pazdur, Director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. Only return the topic.
FDA approval of treatment for Primary HLH (Hemophagocytic lymphohistiocytosis)