Background: Phase 1 clinical trials remain vital for oncology care. Patients on these trials require supportive care for quality-of-life (QOL) concerns. Objective: To test a Palliative Care Intervention (PCI) for patients with solid tumors enrolled in Phase I therapeutic trials with a priori hypothesis that psychological distress, QOL, satisfaction, symptoms, and resource utilization would be improved in the PCI group. Design: This unblinded randomized trial compared the PCI with usual care in patients accrued to Phase I Clinical Trials. Subjects (n = 479) were followed for 24 weeks, with 12 weeks as the primary outcome. Setting: Two Comprehensive Cancer Centers in the United States. Subjects: A consecutive sample, 21 years or older, English fluency, with solid tumors initiating a Phase 1 trial. Measurements: Psychological Distress (Distress Thermometer), QOL total and subscales (FACT-G), satisfaction (FAM-CARE), survival, and resource utilization (chart audit). Results: PCI subjects showed improved Psychological Distress (-0.47, p = 0.015) and Emotional Well-Being (0.81, p = 0.045), with differences on variables of QOL and distress between sites. High rates of symptommanagement admissions (41.3%) and low rates of Advance Directive completion (39.0%), and hospice enrollment (30.7%), despite a median survival in both groups of 10.1 months from initiating a Phase 1 study. Conclusions: A nurse-delivered PCI can improve some QOL outcomes and distress for patients participating in Phase 1 trials. Greater integration of PC is needed to provide quality care to these patients and to support transitions from treatment to supportive care, especially at the end of life. ClinicalTrials.gov Identifier: NCT01612598.