In October 2008, the North American Opiate Medication Initiative (NAOMI) research team released the primary outcomes of a randomized controlled trial aimed at testing whether the provision of pharmaceutical-grade heroin under medical supervision benefits people suffering from chronic opiate addictions who have not benefitted from other treatments. The treatment phase was completed in June 2008. Retention and response rates were high, suggesting that heroin-assisted therapy is a safe and highly effective treatment for people with chronic heroin addiction.