U.S. Food and Drug Administration (FDA) has granted orphan drug designation to 'Leukine' (sargramostim), a product of Partner Therapeutics, Inc., for the treatment of pulmonary alveolar proteinosis (PAP). It is a yeast-derived recombinant human granulocyte-macrophage colony stimulating factor (rhu-GM-CSF) that works by causing stimulation of the leucocyte (WBCs) production and promoting their ability to function properly.
PAP is a rare syndrome characterized by accumulation of surfactant in the lungs that leads to breathing distress. Each year, the disease affects fewer than 5,000 individuals within the U.S. The majority of these patients have antibodies to their own GM-CSF, which is responsible for defective functioning of the macrophages (scavenger cells) in the lung, leading to accumulation of surfactant.
Preliminary clinical trials of Leukine have shown encouraging results. The drug is to be administered via inhalation mode of administration. At present, no approved pharmacological options exist for patients with aPAP. Current standard of care treatment includes whole lung lavage which is invasive and requires hospital admission.
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