Effectiveness of Medical Treatment of Cushing’s Disease: A Systematic Review and Meta-Analysis

Abstract

ObjectiveThe objective of this systematic review was to evaluate the effectiveness and safety of pasireotide, cabergoline, ketoconazole, levoketoconazole, metyrapone, osilodrostat, and temozolomide for the treatment of Cushing’s disease (CD).MethodsThe primary outcomes were the proportion of CD control, adverse events (AE), and reduction of urinary free cortisol. Search strategies were applied to Embase, Medline, and CENTRAL. Independent reviewers assessed the study eligibility, extracted data, and evaluated risk of bias. Standardized mean difference was calculated with 95% confidence interval (CI) for continuous data (i.e., pre- and post-intervention). Random meta-analyses for the proportion of CD control and AE were conducted.ResultsTwenty-nine controlled and non-controlled studies were included. No study with temozolomide and levoketoconazole and one study with osilodrostat fulfilled the inclusion criteria. The meta-analyses of proportion of CD control was 35% for cabergoline (95% CI: 27–43%, six studies, 141 participants), 44% for pasireotide (95% CI: 25–35%, eight studies, 522 participants), 41% for ketoconazole (95% CI: 36–46%, six studies, 450 participants), 66% for metyrapone (95% CI: 46–87%, four studies, 66 participants), and of 66.4% for osilodrostat (95% CI: 57.9, 74.3, 97 participants, one study). One study compared two different treatments (cabergoline vs. ketoconazole), and no statistical difference was observed in CD control (RR: 0.53, 95% CI: 0.15 to 1.87, 14 participants, very low certainty of evidence). The most frequent AE associated with pasireotide was hyperglycemia, dizziness and nausea with cabergoline and metyrapone, and elevated transaminases with ketoconazole.ConclusionThe superiority of one drug over another could not be determined due to lack of controlled studies, but the proportion of disease control identified in our meta-analysis may support clinical decision. New therapeutic options should be investigated due to the limited efficacy and tolerability of the currently available medical treatment for patients with Cushing’s disease.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020205567, identifier CRD42020205567.

Pasireotide-Induced Shrinkage in GH and ACTH Secreting Pituitary Adenoma: A Systematic Review and Meta-Analysis

“…The biochemical efficacy of medical treatment with PAS in GHor ACTH-secreting pituitary adenomas has been described in previous metanalyses for acromegaly (29,30) and CD (15), the latter also exploring the clinical benefit. In addition to these reports, this meta-analysis shows that PAS treatment can induce an additional clinically significant tumor shrinkage in approximately 40% of patients.…”

“…Overall, PAS treatment provided significant tumor shrinkage in 41.2% of CD patients. Regarding pituitary-directed drugs, at this moment available for CD treatment, the efficacy of cabergoline has been proven in vitro studies, but its efficacy in clinical trials is still debated (15,37). In a previous prospective study, cabergoline induced significant tumor shrinkage (defined as tumor volume reduction >20%) in 4 out of 20 (20%) of the patients recruited after 24 months (38).…”

“…These benefits could be maintained for up to 5 years in an extension study (13,14). In a recent meta-analysis, PAS treatment provided disease control in 44% of 522 patients with CD (15). Patients harbouring USP-8 mutations demonstrated an increased SSR type 5 expression in the corticotroph adenoma, increasing the likelihood of a positive response to PAS therapy (16).…”

Osilodrostat — an emerging drug for the medical management of Cushing’s disease

“…Overall, osilodrostat is generally well tolerated and seems to have a good safety profile, which may positively impact treatment compliance. Moreover, a recent meta-analysis showed superiority of osilodrostat over other medications in CD [34].…”

Levoketoconazole

“…2,3 Ketoconazole has been used off label in the United States for the treatment of Cushing syndrome; however, use is associated with hepatotoxicity, QT prolongation, and hypogonadism in males. [3][4][5][6][7][8] Table 1 compares select agents used to treat Cushing syndrome. 1,9,10…”