A pilot randomized clinical trial of a peer support intervention for hematopoietic stem cell transplantation

Peer support has been associated with improved patient-reported outcomes (PROs), including reduced psychological distress, among patients undergoing hematopoietic stem cell transplantation (HSCT), but structured interventions are limited. This study assessed the feasibility, acceptability, and preliminary effects of a scalable peer support intervention to reduce psychological distress and enhance quality of life (QOL) post-HSCT. We conducted a pilot randomized clinical trial evaluating the Supporting Transplant Experiences with Peer Program (STEPP), a 5-session, telephone-based intervention delivered by an HSCT survivor offering psychoeducation and coping strategies. Participants were recruited 1 to 2 weeks pre-HSCT admission and randomized to STEPP or usual care. Feasibility was defined as ≥60% enrollment and ≥60% completing ≥3 sessions. Acceptability was assessed using the Client Satisfaction Questionnaire (CSQ; ≥3/4 mean benchmark). PRO measures of anxiety, depression (Hospital Anxiety and Depression Scale), posttraumatic stress (Post-Traumatic Stress Disorder Checklist-Civilian Version), QOL (Functional Assessment of Cancer Therapy-Bone Marrow Transplant), social support (Social Support and Effectiveness Questionnaire), and self-efficacy (Cancer Self-Efficacy Scale) were assessed pre-HSCT and at 30 and 60 days post-HSCT. Mixed-effects models explored preliminary effects. We enrolled 77% (90 of 117) of eligible patients (STEPP, n = 45; usual care, n = 45); 12 became ineligible due to HSCT cancellation or postponement. Among 78 active participants (mean age, 58.9 years [standard deviation, 12.3]; 57.7% women), all STEPP participants completed ≥3 sessions, and the mean CSQ score was 3.5. STEPP showed small-to-moderate improvements in day 30 anxiety (d = -0.36) and day 60 anxiety (d = -0.58), depression (d = -0.25), posttraumatic stress (d = -0.28), QOL (d = 0.48), social support (d = 0.36), and self-efficacy (d = 0.46). STEPP exceeds feasibility and acceptability thresholds, showing promising psychosocial benefits warranting a fully powered multisite efficacy trial. This trial was registered at www.clinicaltrials.gov as NCT06010017.