- Due to risk of IL2 associated vascular leak and pulmonary edema, patients must have normal respiratory function; this is defined as no evidence of dyspnea at rest, no exercise intolerance, and a pulse oximetry > 94% on room air; if pulmonary function tests (PFTs) are performed, the forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) must be greater than 60%