80 patients with grade 2-3 gluteal tendinopathy were randomized to an intratendinous injection of either leukocyte-rich platelet rich plasma or corticosteroid. Patients were initially followed-up over the first 24 weeks after injection, after which they were given the option of secondary injection with LR-PRP if they had an unsatisfactory response to the first injection. Modified Harris Hip Score were significantly greater in the LR-PRP group compared to the CS group at 12 and 24 weeks, and at 52 and 104 weeks among patients who remained in their originally allocated group. A total of 27 patients of the CS group requested secondary injection with LR-PRP. After 104 weeks, 2 patients in the LR-PRP group and 3 patients in the CS group were referred for surgical intervention.