Tetomilast is primarily investigated for its anti-inflammatory and immunomodulatory properties, making it a potential therapeutic agent for inflammatory diseases. It has been studied for the treatment of chronic obstructive pulmonary disease (COPD) due to its ability to inhibit phosphodiesterase-4 (PDE4), an enzyme involved in inflammatory responses. By reducing inflammation in the airways, it may help alleviate symptoms and improve lung function in COPD patients. Additionally, Tetomilast has shown promise in treating ulcerative colitis, as it can modulate immune responses and reduce inflammation in the gastrointestinal tract. Its potential application extends to other inflammatory conditions, such as rheumatoid arthritis, where it may help control disease progression by targeting inflammatory pathways. Research continues to explore its efficacy and safety in these and other inflammatory disorders.