Toreforant (JNJ-38518168) is an orally-dosed selective antagonist of the histamine H₄ receptor that has been studied for various health conditions. It is the successor of a number of H₄-selective compounds developed by Johnson & Johnson. Phase IIa clinical trials completed as recently as November 2018 continue to suggest that toreforant is safe.

As of the end of 2020, there is no regulator-approved H₄ antagonist. In U.S. Phase II clinical trials, toreforant, by itself, did not show efficacy against eosinophilic asthma. The drug did show at least partial efficacy against rheumatoid arthritis in patients who were nonresponsive to methotrexate. As the H₄ receptor is widely implicated in the regulation of inflammatory states, the potential uses for an H₄ antagonist remain significant.