Geer, Eliza B.

Abstract Context Biochemical test results are central to clinical decision-making for the diagnosis and management of Cushing syndrome (CS). With emerging research and increasing availability of different tests, updated consensus on the utility of these biomarkers is warranted. Objective To establish an updated consensus on the role of biomarkers in the diagnosis and monitoring of adrenocorticotropic hormone-dependent CS, address novel therapeutic approaches, and identify areas for future research. Design A modified 2-round Delphi panel was conducted. Consensus was defined as ≥70% agreement/disagreement for Likert-scale statements or ≥70% selection of the same option for single-choice questions. Setting Participants represented a range of international expertise. Participants Forty-one participants took part in the Delphi panel, with no attrition between rounds (one nonclinician was not required to complete the second round). An 8-member Steering Committee guided statement development. Results Of statements designed to reach consensus, 45% (14/31) and 44% (11/25) statements reached consensus in Rounds 1 and 2, respectively. Notably, most panelists reported the use of late-night salivary cortisol for diagnosis of mild CS and for monitoring following pituitary surgery or medical or radiation therapy. Most panelists responded that block-and-replace therapies can be considered in patients with cyclical or severe CS, and consensus was reached that restoration of circadian rhythm is a treatment goal for patients with CS. Conclusion Areas of alignment among experts on the diagnosis and monitoring of CS are presented. The findings from this study are intended to support clinicians in their clinical decision-making and highlight priority areas for future research.

Abstract Disclosure: M. Fleseriu: None. C.P. Badiu: None. I. Bancos: None. E.B. Geer: None. M. Orbetzova: None. J.M. Silverstein: None. I. Uzunova: None. K.C. Yuen: None. T.K. Marmon: None. D.A. Katz: None. F.S. Czerwiec: None. Introduction: 11β-hydroxysteroid dehydrogenase type 1 (HSD-1) regulates exposures of intracellular receptors to active glucocorticoids. HSD-1 deficiency suppresses a Cushing syndrome (CS) phenotype despite presence of hypercortisolism.1-3 Treatment with clofutriben (C), a potent and specific inhibitor of HSD-1, might improve CS comorbidities by decreasing intracellular cortisol. Methods: Seventeen adults with CS (16 pituitary, 1 ectopic), and type 2 diabetes (T2D), impaired glucose tolerance (IGT), hypertension (HTN), hyperlipidemia, or osteopenia were randomized to a total of 12 weeks of oral C 6mg/d and 12 weeks of matching placebo (P) in 2 blinded sequences (PCCP, CCPP; “P” or “C” representing 6-week periods). Patients were offered open-label C treatment on completion. Primary endpoint was urinary ratio of cortisol and cortisone metabolites at Week 6 (hepatocellular HSD-1 activity biomarker). Key exploratory endpoints (and applicable population) at Week 6 were OGTT-AUCglucose decrease 25% (IGT/T2D), HbA1c decrease ≥ 0.5% (T2D), systolic blood pressure decrease ≥ 5mmHg or decreased treatment (HTN), and normalization of urinary free cortisol (baseline >1.5xULN). Results: Mean baseline HSD-1 ratio was 1.95 +/- 0.171. At Week 6, mean ratio was 0.21 +/- 0.091 with C and 2.01 +/- 0.263 with P. More patients responded at Week 6 to C on OGTT-AUCglucose (4/8 v 0/5), HbA1c (4/5 v 0/4), systolic blood pressure (5/7 v 2/4), and urinary free cortisol (3/8 v 0/6). Concomitant medications for T2D were reduced in 4 C-treated but increased in 2 P-treated patients. For HTN there were also 4 reductions for C-treated and 1 increase for P-treated patients. One patient succumbed to ectopic Cushing’s due to cervical carcinoma after discontinuing the trial. Four patients discontinued for reasons other than an adverse event (AE). One serious AE of vomiting (possible glucocorticoid withdrawal syndrome per investigator) led to temporary drug interruption. Common AEs (≥ 3 patients) included Arthralgia, Fatigue, Headache, and Nausea, but only Headache was more common in C during the P-controlled period. There was no evidence of clinical or biochemical (defined by low morning plasma cortisol) adrenal insufficiency. All 13 patients who completed elected to enter the open-label extension (current treatment duration 3-15 months). Conclusions: Clofutriben decreased hepatic HSD-1 activity adequately to confer clinical benefit while maintaining safety and overall tolerability. These limited data support clofutriben’s potential for clinical improvement without adrenal insufficiency. References: 1Tomlinson JW 2002; 2Arai H 2008; 3Weber RJ 2024 Presentation: Sunday, July 13, 2025

Abstract Disclosure: I. Bancos: Adrenas, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), AstraZeneca, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), Corcept Therapeutics, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), Diurnal, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), HRA Pharma, consulting, advisory board, data safety monitoring board fees (paid to institution outside this work), or funding for investigator-initiated research, Neurocrine, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), NovoNordisk, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), Recordati Rare Diseases, consulting, advisory board, data safety monitoring board fees (paid to institution outside this work), or funding for investigator-initiated research, Sparrow, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), Spruce, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work), Xeris, consulting, advisory board, or data safety monitoring board fees (paid to institution outside this work). F. Castinetti: HRA Pharma, consultancy for and research grants, Lundbeck, consultancy for and research grants, Recordati Rare Diseases, consultancy for and research grants. E.B. Geer: Corcept Therapeutics, research grants to her hospital, Recordati Rare Diseases, research grants to her hospital and occasional consulting honoraria, Sparrow, research grants to her hospital and occasional consulting honoraria, Xeris Pharmaceuticals (Strongbridge), research grants to her hospital and occasional consulting honoraria, Crinetics Pharmaceuticals, occasional consulting honoraria, HRA Pharma, occasional consulting honoraria, Lundbeck, occasional consulting honoraria, Member of the LINC 6 steering committee. S. Espiard: Recordati Rare Diseases, reports invitations to training courses and medical congresses. C. Mouly: Pfizer, consulting and advisory board fees, Recordati Rare Diseases, consulting and advisory board fees. L. Dichtel: Lumos Pharma, consultant and received research support to her hospital, Novo Nordisk, consultant and received research support to her hospital, Perspectum, received research support to her hospital, Recordati Rare Diseases, research support to her hospital, Flare Therapeutics, consultant, Marea Therapeutics, consultant and has equity in company, Third Rock Ventures, consultant, Merida Biosciences, consultant and has equity in company. E.V. Varlamov: Lumiio, research support to her university, Novo Nordisk, research support to her university, Pfizer, research support to her university, Recordati Rare Diseases, research support to her university. A. Ferriere: Novo Nordisk, Recordati Rare Diseases. E. Nowak: Supported by the Else Kröner-Fresenius–Stiftung and the Eva Luise und Horst Köhler–Stiftung within the Clinician Scientist program RISE (2022_EKFKSE.03). C. Simeoli: Neurocrine UK Ltd, consultancy, Recordati Rare Diseases, consultancy. R.A. Feelders: HRA Pharma, consultancy, Recordati Rare Diseases, consultancy, Corcept Therapeutics, research grant, Member of the LINC 6 steering committee. J. Le Mouhaër: Recordati Rare Diseases, employee. P. Raunioniemi: Recordati Rare Diseases, employee. A. Mueller: Recordati Rare Diseases, employee. N. Scheyer: HRA Pharma, invitations to training courses and medical congresses, Pfizer, invitations to training courses and medical congresses, Recordati Rare Diseases, invitations to training courses and medical congresses. Introduction: LINC 6 (NCT05382156) is an ongoing prospective, observational study evaluating the long-term safety and effectiveness of osilodrostat, a potent 11β-hydroxylase inhibitor, over 3 years in patients (pts) with Cushing’s syndrome (CS). We report results from a prespecified 2-year interim analysis. Methods: Adult pts with endogenous CS were enrolled in 5 countries (USA and Europe) where osilodrostat is approved and available. The primary objective is long-term safety and tolerability, assessed by incidence of osilodrostat-related adverse events (AEs) and serious AEs (SAEs), with a focus on hypocortisolism-, adrenal hormone precursor accumulation-, arrhythmia/QT prolongation-, and pituitary tumor enlargement-related AEs. Secondary effectiveness endpoints include change in mean urinary free cortisol (mUFC) and late-night salivary cortisol (LNSC). Here, we report AEs in the safety population (≥1 osilodrostat dose; n=206) among pts with Cushing’s disease (CD) and non-pituitary CS (non-PCS, adrenal or ectopic CS; data cutoff July 2024). Results: Data were available for 205 pts: 75.6% were female, mean (standard deviation) age was 53.0 (14.4) years. 161 pts had CD and 44 had non-PCS (adrenal adenoma, n=12; adrenal carcinoma, n=2; bilateral adrenal nodular disease, n=10; ectopic adrenocorticotropic hormone secretion, n=17; other, n=3). Median (min-max) on-study osilodrostat exposure and dose were 8.3 months (0.0-20.8) and 5.0 mg/day (0.5-80.0). 34 (21.1%) CD and 9 (20.5%) non-PCS pts reported 91 and 14 AEs considered treatment related, respectively; most were mild or moderate (95.6% CD and 85.7% non-PCS). Most common (>5% of events) treatment-related AEs: CD, adrenal insufficiency (9.9%, n=9/91 events), diarrhea, dizziness, fatigue (6.6% [n=6/91] each) and nausea (5.5%, n=5/91); non-PCS, adrenal insufficiency (42.9%, n=6/14 events), hypokalemia (14.3%, n=2/14), abnormal hormone (cortisol) level, dizziness, hirsutism, joint stiffness, musculoskeletal stiffness, and nervous system disorder (7.1% [n=1/14] each). 17 (10.6%) CD and 10 (22.7%) non-PCS pts reported 29 and 16 SAEs (7 and 4 were considered treatment related), respectively. 5 (3.1%) CD and 2 (4.5%) non-PCS pts discontinued because of 8 and 3 treatment-related AEs. CD and non-PCS pts reported 21 and 9 hypocortisolism-related AEs, 16 and 6 adrenal hormone precursor accumulation-related AEs, and 3 and 0 arrhythmogenic potential/QT interval prolongation-related AEs, respectively. CD pts had 3 pituitary tumor enlargement-related AEs. At month 3, mUFC and LNSC were normal in 73.9% (n=34/46) and 56.3% (n=18/32) of pts. By month 6, mUFC and LNSC were normal in 63.0% (n=29/46) and 30.4% (n=7/23) of pts. Conclusions: These LINC 6 2-year interim data show that osilodrostat is effective for the management of different etiologies of CS. AEs were mostly mild or moderate, with few leading to treatment discontinuation. Presentation: Sunday, July 13, 2025

Abstract Introduction Endogenous Cushing's syndrome (CS) is a rare endocrine disorder that chronically exposes patients to supraphysiological cortisol levels. Primary therapy for CS consists of surgery. Medical therapies are also considered for many patients with CS, including those who are not surgical candidates or have persistent or recurrent hypercortisolism after surgery. Osilodrostat, an adrenal steroidogenesis inhibitor, demonstrated sustained efficacy and safety in phase 3 clinical trials and is currently approved to treat endogenous CS in Europe and the United States. Because of limited clinical experience, questions remain about how to individualize osilodrostat treatment for different clinical scenarios and special populations. Additional guidance from experts based on clinical study and real-world experiences with osilodrostat is needed. Methods A modified Delphi consensus panel study was conducted consisting of 13 specialists from high-volume endocrinology centers with experience prescribing osilodrostat. Advisors participated in 3 consensus rounds (2 anonymous surveys, 1 virtual workshop) over approximately 10 months to provide guidance and recommendations on optimal osilodrostat use. Results Over 2 surveys and a 2-hour virtual workshop, 26 statements related to osilodrostat achieved consensus among Delphi panelists and 5 were excluded. Topics included patient preparation before osilodrostat initiation, baseline testing, dosing at onset and during treatment, managing dose adjustments, monitoring during dose titration, and treatment alterations for planned and unexpected clinical events. Conclusion Treatment guidance and recommendations for osilodrostat use were obtained using the Delphi method. These statements are intended to provide physicians with education and guidance on using osilodrostat to optimally treat patients with CS.

Abstract Disclosure: I. Bancos: Advisory Board Member; Self; Adrenas, Diurnal, Neurocrine, Spruce, HRA Pharmaceuticals, Sparrow, Recordati Rare Diseases, Xeris, Novo Nordisk, AstraZeneca, Corcept. Consulting Fee; Self; Adrenas, Diurnal, Neurocrine, Spruce, HRA Pharmaceuticals, Sparrow, Recordati Rare Diseases, Xeris, Novo Nordisk, AstraZeneca, Corcept. Grant Recipient; Self; Recordati, HRA Pharmaceuticals. Other; Self; Adrenas, Diurnal, Neurocrine, Spruce, HRA Pharmaceuticals, Sparrow, Recordati Rare Diseases, Xeris, Novo Nordisk, AstraZeneca, Corcept. E.B. Geer: Advisory Board Member; Self; Recordati Rare Diseases. Consulting Fee; Self; Lundbeck, Crinetics, HRA Pharmaceuticals, Recordati Rare Diseases, Sparrow, Xeris Pharmaceuticals (Strongbridge). Grant Recipient; Self; Xeris Pharmaceuticals (Strongbridge), Corcept, Recordati Rare Diseases, Sparrow. F. Castinetti: Consulting Fee; Self; HRA Pharmaceuticals, Recordati. Grant Recipient; Self; HRA Pharmaceuticals, Recordati. R. Feelders: Advisory Board Member; Self; Recordati. Consulting Fee; Self; HRA Pharmaceuticals, Recordati. Grant Recipient; Self; Corcept Therapeutics. M. Fleseriu: Advisory Board Member; Self; Recordati Rare Diseases. Consulting Fee; Self; Recordati Rare Diseases, Sparrow, Xeris Pharmaceuticals (Strongbridge). Grant Recipient; Self; Recordati Rare Diseases, Sparrow, Xeris Pharmaceuticals (Strongbridge). R. Pivonello: Consulting Fee; Self; Corcept Therapeutics, Recordati, Crinetics Pharmaceuticals, H Lundbeck. Grant Recipient; Self; Recordati, Corcept Therapeutics, Xeris Pharmaceuticals (Strongbridge), Neurocrine Biosciences. M. Reincke: Advisory Board Member; Self; Recordati Rare Diseases. Consulting Fee; Self; Recordati Rare Diseases, HRA Pharmaceuticals, Lundbeck, Crinetics. Grant Recipient; Self; Recordati Rare Diseases, HRA Pharmaceuticals, Lundbeck, Crinetics. Speaker; Self; Recordati Rare Diseases, HRA Pharmaceuticals, Lundbeck, Crinetics. A. Tabarin: Advisory Board Member; Self; Recordati Rare Diseases. Consulting Fee; Self; H Lundbeck, Crinetics, HRA Pharmaceuticals, Recordati Rare Diseases. J. Le Mouhaër: Employee; Self; Recordati. J. Stermenska: Employee; Self; Recordati. M. Maldonado: Employee; Self; Recordati. B.M. Biller: Advisory Board Member; Self; Recordati Rare Diseases. Consulting Fee; Self; H Lundbeck, Recordati Rare Diseases, Sparrow, Xeris Pharmaceuticals (Strongbridge). Introduction: Osilodrostat, a potent oral 11β-hydroxylase inhibitor, provides control of cortisol production and improves outcomes in patients (pts), as shown by the clinical development program of Cushing’s disease (CD; Fleseriu M et al. Lancet Diabetes Endocrinol 2021;9:847-75) leading to EMA approval for Cushing’s syndrome (CS) and FDA approval for CD. The prospective LINC 6 study (NCT05382156) evaluates long-term safety and efficacy of osilodrostat in routine clinical practice over a 3-­year follow-up of CS pts. Here, we report 1-year interim data. Methods: Pts aged ≥18 years with endogenous CS are being enrolled in countries where osilodrostat is approved and available (including USA and Europe), irrespective of prior osilodrostat use. Treatment decisions and follow-up are at investigator discretion. The primary endpoint is incidence of osilodrostat-related adverse events (AEs) and serious AEs, focusing on AEs related to hypocortisolism, accumulation of adrenal hormone precursors, QT prolongation and pituitary tumor enlargement. Secondary endpoints include change in mean urinary free cortisol (mUFC), serum cortisol and late-night salivary cortisol (LNSC). Evaluation of biochemical parameters is recommended at baseline, months 1 and 3, and every 3 months thereafter, as available. AEs are recorded at baseline and each visit. Analyses are descriptive. We report change for pts with assessments at baseline and every 3 months. Results: Of 106 pts enrolled at the 1-year interim analysis, 94 were included in the safety population: CD, n=78; non-CD CS, n=16 (adrenal adenoma, n=3; adrenal hyperplasia, n=3; ectopic, n=9; other, n=1). Mean (SD) age was 53.2 years (12.7); 70.2% (n=66) were female. Median (min-max) osilodrostat exposure and dose were 5.5 months (0.1-13.9) and 5.0 mg/day (1.0-60.0). 29 pts reported 109 AEs; 12 pts reported 44 AEs that were considered treatment related. Overall, the most common (≥5%) AEs were asthenia and vomiting (both n=6/109; 5.5%); treatment-related AEs with highest frequency were vomiting and dizziness (both n=4/44; 9.1%). 7 AEs led to discontinuation in 4 pts; 5 AEs were considered osilodrostat related (nausea and vomiting in 1 pt; worsening hypertension, uncontrolled blood pressure and dizziness in another) and 2 were not (pituitary tumor surgery and right adrenalectomy). AEs related to hypocortisolism, accumulation of adrenal hormone precursors, QT prolongation and pituitary tumor enlargement occurred in 7 (7.4%), 4 (4.3%), 2 (2.1%) and 0 pts, respectively. At month 3, mUFC, serum cortisol and LNSC were normalized in 71.4% (n=10/14), 69.2% (n=18/26) and 50.0% (n=7/14) of pts. Conclusions: Results from this real-world clinical setting show that osilodrostat is generally well tolerated and provides early improvements in mUFC and LNSC in pts with endogenous CS, building on evidence from the previous randomized, controlled trials LINC 3 and LINC 4. Presentation: 6/3/2024