ATB-346 is a hydrogen sulfide-releasing derivative of naproxen designed to provide anti-inflammatory and analgesic effects with reduced gastrointestinal side effects compared to traditional nonsteroidal anti-inflammatory drugs (NSAIDs). It is primarily investigated for the treatment of osteoarthritis and other chronic inflammatory conditions. By releasing hydrogen sulfide—a molecule known to protect the gastric mucosa—ATB-346 maintains the pain-relieving and anti-inflammatory benefits of naproxen while significantly lowering the risk of stomach ulcers and gastrointestinal damage. This makes it a promising candidate for long-term pain management in patients who require NSAID therapy but are at high risk for GI complications. Clinical studies have focused on its safety profile and efficacy in reducing inflammation and pain with improved gastrointestinal tolerance.