The European and American Osteosarcoma study group (EURAMOS) was formed by four multinational study groups (COG, COSS, EOI, SSG) based upon a common understanding that broad international collaboration facilitating randomised trials was important for further progress in the field of osteosarcoma. Representatives from each group reached quick agreement on a study design; to determine whether altering post-operative therapy based on response to pre-operative chemotherapy improves outcome. Additionally, a quality-of-life sub-study was included in the project. After a three-year process to resolve regulatory and organisational issues the study opened for accrual in April 2005. Important for an efficient conduction of the trial a common infrastructure was established with central sponsorship (Medical Research Council, UK), one coordinating data centre (MRC Clinical Trials Unit, UK) and a common Safety Desk and a coordinating Quality-of-life data centre (Münster, DE). As of Dec 2008, a total of 1268 patients from 290 institution in 15 countries have been registered into the trial (AUS 16 patients; B 27; CAN 54; CH 26; D 266; DK 12; FIN 3; H 14; NL 61; NOR 23; NZ 8; OST 7; SWE 25; UK 174; USA 552) and 937 patients participate in the quality-of-life evaluation. 697 patients have been randomized and 53% are assessed as good histological responders. Due to a lower than expected randomisation rate and a higher than expected number of patients with a good histological response the accrual time will be extended by one year to summer 2010. In conclusion, EURAMOS-1 may serve as a model for a successful non-commercial multinational clinical trial in times of increasing economic and regulatory pressure. It is the fastest accruing and largest osteosarcoma trial ever. In addition, to addressing important questions in a randomised setting a common language in osteosarcoma has been established. Supported by the European Science Foundation (ESF) under the EUROCORES Program European Clinical Trials (ECT), through contract No. ERASCT-2003-980409 of the European Commission, DG Research, FP6
