Growth Modulation Index (Gmi) As A Metric Of Clinical Benefit Assessment Among Advanced Soft Tissue Sarcoma (Asts) Patients Receiving Trabectedin As Salvage Therapy

10013 Background: Von Hoff has proposed GMI u003e1.33 in cancer clinical trials as a sign of drug activity. GMI is the ratio between time to progression (TTP) with the nth line (TTPn) of therapy divided by the TTPn-1 with the n-1th line of therapy. With this endpoint, each patient is his/her own control. Methods: We have carried out a retrospective analysis of 279 pretreated ASTS patients treated in four consecutive phase II trials with trabectedin 1.5 mg/m², given as a 24-hour infusion every 3 weeks. Results: The study population consisted of 170 women and 109 men with a median age of 52. The two most common histologies were leiomyosarcoma (145 patients, 52%) and liposarcoma (59, 21%). 142 (51%) patients received one prior line and 137 (49%) ≥2 lines. The median TTPn was 2.8 months (range: 0.2-26.8), whereas the median TTPn-1 was 4.0 months (range: 0.3-79.5). The Spearman correlation coefficient between TTPn-1 and TTPn was 0.07 (p=0.23). The median GMI was 0.6 (range: 0.0-14.4). 177 patients (63%) had a GMI ...