Hospitalizations in solid tumor phase I clinical trial patients: Incidence, pattern and clinical outcomes at an Australian phase I clinical trial unit.

BACKGROUND Participation in early-phase clinical trials has become a prominent part of medical oncology patient management. We examined the incidence and pattern of hospitalizations in early-phase clinical trial patients and the associated clinical outcomes. METHOD We conducted a retrospective review of 194 patients with solid tumors treated on phase I clinical trials between July 2014 and October 2018 at a phase I trial unit. Unplanned hospitalizations occurring during the study period were characterized and correlated with treatment response and duration of trial participation. RESULTS Among 194 patients, 104 hospitalizations were recorded involving 62 patients (31%). Nineteen percent of patients were hospitalized for cancer-related complications and 8% for treatment toxicity. No significant correlation was seen between the hospitalization and age, sex, tumor type, or trial drug. Best response to trial therapy was complete response, partial response, stable disease, and progressive disease in 5%, 11%, 37%, and 47% of patients, respectively. Median duration on trial was 86 days (range 0-1,412). Twenty-two patients (11%) remained on trial for more than 12 months. Overall, hospitalization did not impact treatment response or trial duration. However, cancer-related hospitalization was associated with significantly lower response (p < 0.001) and early patient attrition (p < 0.001). Resolution of the hospitalization event was associated with improved response (p = 0.002) and longer duration on trial (p < 0.001). The treatment related mortality was 0.5% (n = 1). CONCLUSION Approximately one third of patients required hospitalization, most commonly for cancer-related complications which correlated with poorer clinical outcomes. Hospitalizations related to treatment toxicity were infrequent. A significant proportion of patients derived significant therapeutic benefit. Phase I clinical trials provide a valuable treatment option for patients with cancer.