The discovery and preclinical pharmacology of JNJ-10450232 (NTM-006), a centrally penetrant, non-opioid structural analog of acetaminophen with comparable analgesic and anti-pyretic properties but no evidence of hepatotoxicity.

A mainstay of the analgesic pharmacopeia for nearly seven decades and alone in its class, acetaminophen relieves mild-to-moderate pain and fever, without similar adverse gastrointestinal and cardiovascular effects associated with non-steroidal anti-inflammatory drugs. While safe and effective when used as directed, acetaminophen overdose may produce liver injury. This report describes discovery and pharmacological characterization of JNJ-10450232/NTM-006, an acetaminophen structural analog designed to retain the efficacy and overall safety profile of acetaminophen without risk of hepatotoxicity following overdose. In the carrageenan and complete Freund's adjuvant models of inflammatory pain and yeast model of fever in rats, JNJ-10450232/NTM-006 exhibited statistically significant effects comparable to acetaminophen in both maximal efficacy and potency. In rat pharmacokinetic studies, JNJ-10450232/NTM-006 exhibited a comparable maximal plasma concentration but higher volume of distribution and longer half-life than acetaminophen, potentially conferring an extended duration of action. In a mouse model of liver injury, acetaminophen produced elevations in aspartate and alanine transaminase activities and signs of hepatic necrosis, whereas JNJ-10450232/NTM-006 did not. Finally, following systemic administration, JNJ-10450232/NTM-006 and acetaminophen produced comparable peripheral levels of para-aminophenol and brain levels of pharmacologically active metabolite N-arachidonoyl-phenolamine (AM404), consistent with the hypothesis that both parent molecules are prodrugs and share the same central mechanism of analgesic action. Taken together, these results suggest JNJ-10450232/NTM-006 as a potentially clinically useful analgesic/antipyretic with improved benefit-to-risk ratio compared with current standards of care.