Repository Corticotropin Versus Glucocorticoid for Nephrotic Syndrome: When Will We See the Evidence?

Despite little evidence supporting its superiority to glucocorticoid therapy, use and expenditures for repository corticotropin (rACTH) injection (H.P. Acthar Gel; Mallinckrodt) have increased dramatically in the last 5 years, particularly among a small number of nephrologists, rheumatologists, and neurologists. Recently, the manufacturer justified the extremely high and rapidly increasing cost of rACTH by citing the ongoing need to generate clinical data to support its use. We test this assertion by investigating the quality and provenance of the evidence likely to emerge in the foreseeable future. We identified all completed, in-progress, and proposed studies of rACTH registered at ClinicalTrials.gov. 75 studies representing 2,953 participants met inclusion criteria. Studies addressed primarily nephrologic (n = 23), rheumatologic (n = 28), and neurologic (n =22) indications. Of the 23 studies proposed for renal indications (enrollment, 33 ± 49 [mean ± SD]), 11 were not randomized, 8 compared only different rACTH treatment regimens, and 4 compared rACTH to placebo. No studies of rACTH proposed for renal indications included an rACTH-free arm receiving active treatment (ie, another form of immunosuppression). We conclude that evidence emerging in the foreseeable future is unlikely to broadly support rACTH use over lower-cost glucocorticoid-based alternatives for renal indications.