"The central result of the German model project shows a significant superiority of heroin over methadone treatment for both primary outcome measures. Heroin treatment has significantly higher response rates both in the field of health and the reduction of illicit drug use. According to the study protocol, evidence of the greater efficacy of heroin treatment compared to methadone maintenance treatment has thus been produced. Heroin treatment is also clearly superior to methadone treatment when focusing on patients, who fulfill the two primary outcome measures."
Haasen C, Vertheim U, Degkwitz P. The German Model Project for Heroin Assisted Treatment of Opioid Dependent Patients. A Multicentric, Randomized, Controlled Treatment Study. Centre for Interdisciplinary Addiction Research of Hambur University (ZIS); Germany: 2006.