Validation of the Royal Marsden Hospital (RMH) prognostic score on an enriched early treatment line cohort for phase I trial patients

Background: The RMH score has been validated to predict survival in different populations of patients starting phase I clinical trials. Most of the populations where it has been validated are of heavily treated patients that lack other treatment options. The type of phase I trials is changing and we aimed to validate the score in a new cohort with more patients treated on an early line, rahter than the usual classic phase I trials heavily pretreated patient population. Methods: We analyzed the RMH score in the patients treated in our center in a phase I trial between 2012 and 2017. We collected demographics data, overall survival after starting the trial, the RMH score (albumin, LDH, and number of metastatic sites) for all patients and the treatment line. We considered a late line anything over two treatment lines and in any case if the patient did not have any other treatment available depending on the tumor type. An early line was the first or second treatment line when the patient did have further lines available. Results: We treated 77 patients on a phase I trial in our institution, 23 males and 54 females. Mean age was 55 years (26-77). RMH score was (0/1/2/3) in (31/23/20/3) patients. Thirty-three patients were treated on an early line. Median survival for low score (0/1) was 639 days and for high score (2/3) was 327 days p = 0.0834. The mean survival for patients with low RMH score was higher than those with a high RMH score in every treatment line, although due to the low number of patients in some of those categories the difference was not significant. Conclusions: The RMH score did predict well the overall survival in our patients. The survival times in our institution are higher than those previously published, probably due to the inclusion of patients on earlier treatment lines than those used before to calculate and validate the score. Our findings support the use of the RMH score for the selection of patients entering phase I trials irrespectively of the design of the trial (early vs. late line). Legal entity responsible for the study: Medical Oncology Department, Hospital General Universitario Gregorio Marañón Funding: Instituto de Investigación Sanitaria Hospital Gregorio Marañón Disclosure: All authors have declared no conflicts of interest.