Shionogi & Co. Ltd. has in-licensed Japan rights to Grunenthal GmbH’s intra-articular injectable, resiniferatoxin, for the treatment of pain associated with osteoarthritis of the knee. Currently in phase III trials, RTX is a transient receptor potential vanilloid 1 agonist, which can reversibly desensitize TRPV1-expressing nociceptors. This mechanism may result in long-lasting pain relief.