GPT and empyema: Four patients encountered non-fatal serious adverse events (SAEs) during the study, including bilateral pulmonary embolism (0.06 mg/kg ALT-836-treated patient), hypoxic respiratory failure (0.1 mg/kg ALT-836-treated patient), worsening acute renal failure (placebo-treated patient), and worsening anemia and empyema (placebo-treated patient).