The National Institute of Neurological Disorders and Stroke, National Institute of Aging, the NIH Helping to End Addiction Long Term (HEAL) initiative, and other participating NIH Institutes/Centers (ICs) seek to support applications to develop in vitro, ex vivo or in vivo assays and conduct screening efforts with the goal of identifying and characterizing potential therapeutic agents for disorders or diseases supported by participating ICs, or for non-opioid analgesic therapeutics with little or no addiction liability as a part of the NIH Helping to End Addiction Long Term (HEAL) initiative. Therapeutic agents include small molecules and biologics. Assays utilizing New Approach Methodologies (NAMs) may be used when appropriate.