Crinetics Pharmaceuticals (CRNX) Reports Positive Top-line Results Including Strong Adrenal Suppression from CRN04894 Phase 1 Study

Crinetics Pharmaceuticals, Inc. (Nasdaq: CRNX) today announced positive results from the multiple-ascending dose (MAD) portion of a first-in-human Phase 1 clinical study of CRN04894, the company’s first-in-class, investigational, oral, nonpeptide adrenocorticotropic hormone (ACTH) antagonist that is being developed for the treatment of Cushing’s disease, congenital adrenal hyperplasia (CAH) and other conditions of excess ACTH. Following administration of CRN04894, results showed serum cortisol below normal levels and a marked reduction in 24-hour urine free cortisol excretion in the presence of sustained, disease-like ACTH concentrations.

“The design of our Phase 1 healthy volunteer study allowed us to demonstrate CRN04894’s potent pharmacologic activity in the presence of ACTH levels that were in similar range to those seen in CAH and Cushing’s disease patients,” said Alan Krasner, M.D., Crinetics’ chief medical officer. “The observation of dose-dependent reductions in serum cortisol levels to below the normal range even in the presence of high ACTH indicates that CRN04894 was effective in blocking the key receptor responsible for regulating cortisol secretion. We believe this is an important finding that may be predictive of CRN04894’s efficacy in patients.”

ACTH is the key regulator of the hypothalamic-pituitary adrenal (HPA) axis controlling adrenal activation. It is regulated by cortisol via a negative feedback loop that acts to inhibit ACTH secretion. This feedback loop is dysregulated in diseases of excess ACTH. In Cushing’s disease, a benign pituitary tumor drives excess ACTH secretion even in the presence of excess cortisol. While in CAH, an enzyme deficiency results in excess androgen synthesis without normal cortisol synthesis, allowing unchecked ACTH production and requiring lifelong glucocorticoid use. In both diseases, excess ACTH drives over-stimulation of the adrenal gland and leads to a host of symptoms including infertility, adrenal rest tumors, and metabolic complications in CAH and, in Cushing’s disease, symptoms include hypertension, central obesity, neuropsychiatric disorders and metabolic complications. To our knowledge, no other ACTH antagonists are currently in clinical development for diseases of ACTH excess such as Cushing’s disease or CAH.

The 49 healthy adults evaluated in the multiple ascending dose portion of the Phase 1 study were administered 40, 60 or 80 mg doses of CRN04894, or placebo, daily for 10 days. After 10 days of dosing was complete, evaluable participants were administered an ACTH challenge to stimulate adrenal activation to disease relevant levels. Safety and pharmacokinetic data were consistent with expectations from the single-ascending dose cohorts in the Phase 1 study. There were no discontinuations due to treatment-related adverse events and no serious adverse events reported. Glucocorticoid deficiency was the most common treatment-related adverse event in the MAD cohorts. This was an expected extension of pharmacology given the mechanism of action of CRN04894. CRN04894 showed consistent oral bioavailability in the MAD cohorts with a half-life of approximately 24 hours, which is anticipated to support once-daily dosing.

Participants in the MAD cohorts who were administered once nightly CRN04894 experienced a dose-dependent suppression of adrenal function as measured by suppression of serum cortisol production of 17%, 29% and 37% on average from baseline over 24 hours for the 40, 60 or 80 mg dosing groups respectively, (despite requirement for glucocorticoid supplementation in some of these subjects to prevent clinical adrenal insufficiency), compared to an average 2% increase in serum cortisol for individuals receiving placebo. The strong, dose-dependent suppression of serum and urine free cortisol was achieved despite ACTH levels in subjects in the 60 and 80 mg cohorts similar to those typically seen in patients with CAH and Cushing’s disease. Even when an additional exogenous ACTH challenge was administered on top of the already increased ACTH levels, cortisol levels remained below the normal range in subjects receiving CRN04894, indicating clinically significant suppression of adrenal activity.

“Due to its central position in HPA axis, ACTH is the obvious target for inhibiting excessive stimulation of the adrenal in diseases of ACTH excess. Even though the field of endocrinology has known about its clinical significance for more than 100 years, we are not aware of any other ACTH antagonist that has entered clinical development. This is an important milestone for endocrinology and for our company.” said Scott Struthers, Ph.D., founder and chief executive officer of Crinetics. “We are very excited to initiate patient studies in Cushing’s disease and CAH with CRN04894, which will be our third home-grown NCE to demonstrate pharmacologic proof-of-concept and enter patient trials.”

Crinetics plans to present additional details of safety, efficacy, and biomarker results from the CRN04894 Phase 1 study at an endocrinology-focused medical meeting in 2022.

Data Review Conference Call Crinetics will hold a conference call and live audio webcast today, May 25, 2022, at 8:00 a.m. Eastern Time to discuss results from the MAD cohorts of the Phase 1 study of CRN04894. To participate, please dial 1-877-407-0789 (domestic) or 1-201-689-8562 (international) and refer to conference ID 13730000. To access the webcast, click here. Following the live event, a replay will be available on the Events page of the Company’s website.

About the CRN04894 Phase 1 Study Crinetics has completed enrollment of the 88 healthy volunteers in this double-blind, randomized, placebo-controlled Phase 1 study. Participants were divided into multiple cohorts in the single ascending dose (n=39) and multiple ascending dose (n=49) portions of the study. In both the SAD and MAD portions of the study, safety and pharmacokinetics were assessed. In addition, pharmacodynamic responses were evaluated before and after challenges with injected synthetic ACTH to assess pharmacologic effects resulting from exposure to CRN04894.


Recordati Rare Diseases Announce Publication in the Journal of Clinical Endocrinology & Metabolism of the Phase III LINC 4 Study Confirming the Efficacy and Safety of Isturisa® (Osilodrostat) in Patients With Cushing’s Disease

The LINC 4 study demonstrated superiority of Isturisa® (osilodrostat) over placebo in achieving cortisol normalisation during the 12-week, double-blind, randomised phase (77% vs 8%, P<0.0001).

Isturisa provided rapid and sustained control of cortisol secretion in the majority of patients throughout the 48-week core phase of the study.

PUTEAUX, France, March 29, 2022–(BUSINESS WIRE)–Recordati Rare Diseases announce today the publication of positive results from the Phase III LINC 4 study of Isturisa in The Journal of Clinical Endocrinology & Metabolism.1 These data reinforce Isturisa as an effective and well-tolerated oral therapy for patients with Cushing’s disease. Isturisa is indicated in the EU for the treatment of adult patients with endogenous Cushing’s syndrome,2 a rare and debilitating condition of hypercortisolism that is most commonly caused by a pituitary adenoma (Cushing’s disease).3

The LINC 4 study augments the efficacy and safety data for Isturisa in patients with Cushing’s disease, confirming the results from the Phase III LINC 3 study. This study in 73 adults is the first Phase III study of a medical treatment in patients with Cushing’s disease to include an upfront, randomised, double-blind, placebo-controlled period during which 48 patients received Isturisa and 25 received placebo for the first 12 weeks, followed by an open-label period during which all patients received Isturisa until week 48; thereafter, patients could enter an optional extension phase.

Key findings published in the manuscript entitled ‘Randomised trial of osilodrostat for the treatment of Cushing’s disease’ include:1

  • LINC 4 met the primary endpoint: Isturisa was significantly superior to placebo at normalising mUFC at the end of a 12-week randomised, double-blind period (77% vs 8%; P<0.0001).
  • Effects of Isturisa were rapid. Over one-quarter of patients randomised to Isturisa achieved normal mUFC as early week 2 and 58% achieved control by week 5.
  • The key secondary endpoint was also met, with 81% of all patients in the study having normal mUFC at week 36.
  • Improvements in cardiovascular and metabolic parameters of Cushing’s disease, including blood pressure and blood glucose metabolism, were seen by week 12 and were maintained throughout the study.
  • Physical features of hypercortisolism improved during Isturisa treatment, including fat pads, facial rubor, striae, and muscle wasting. Improvements were observed by week 12, with continued improvement throughout the study to week 48.
  • Patient-reported QoL scores (CushingQoL and Beck Depression Inventory) also improved during Isturisa treatment.
  • Isturisa was well tolerated in the majority of patients, with no unexpected adverse events (AEs). The most common AEs overall were decreased appetite, arthralgia, fatigue and nausea.

“These results show convincingly that osilodrostat is an effective treatment for Cushing’s disease,” said Peter J. Snyder MD, Professor of Medicine at the University of Pennsylvania. “Osilodrostat rapidly lowered cortisol excretion to normal in most patients with Cushing’s disease and maintained normal levels throughout the core phase of the study. Importantly, this normalisation was accompanied by improvements in cardiovascular and metabolic parameters, which increase morbidity and mortality in Cushing’s disease.”

“These compelling data build on the positive Phase III LINC 3 study, published in The Lancet Diabetes & Endocrinology in 2020,4 demonstrating that Isturisa enables most patients with Cushing’s disease to gain rapid control of their cortisol levels, which in turn provides relief from a host of undesirable symptoms,” said Alberto Pedroncelli, Clinical Development & Medical Affairs Lead, Global Endocrinology, Recordati AG. “Recordati Rare Diseases is committed to improving the lives of patients with this rare, debilitating and life-threatening condition. I would like to thank everyone who has contributed to LINC 4 and the LINC clinical programme.”

“I had Cushing’s disease for 8 years without being diagnosed,” said Thérèse Fournier from L’association “Surrénales”. “I was trapped in a vicious circle of missed diagnoses and worsening physical and psychological symptoms that became life-threatening. I lost everything – my job, my house, my partner, my friends – I was isolated. When I finally received my diagnosis, I was relieved because I knew the truth. Since my surgery, I have been learning to live again, enjoying the moments that make a life. I am still on the path to remission, but I feel deeply happy, even if I carry this journey that nobody can understand.”

About Cushing’s syndrome
Cushing’s syndrome is a rare disorder caused by chronic exposure to excess levels of cortisol from either an exogenous (eg medication) or an endogenous source.5 Cushing’s disease is the most common cause of endogenous Cushing’s syndrome and arises as a result of excess secretion of adrenocorticotropic hormone from a pituitary adenoma, a tumour of the pituitary gland.5,6 There is often a delay in diagnosing Cushing’s syndrome, which consequently leads to a delay in treating patients.7 Patients who are exposed to excess levels of cortisol for a prolonged period have increased comorbidities associated with the cardiovascular and metabolic systems, which consequently reduce QoL and increase the risk of mortality.3,6 To alleviate the clinical signs associated with excess cortisol exposure, the primary treatment goal in Cushing’s syndrome is to reduce cortisol levels to normal.8

About LINC 4
LINC 4 is a multicentre, randomised, double-blind, 48-week study with an initial 12-week placebo-controlled period to evaluate the safety and efficacy of Isturisa® in patients with Cushing’s disease. The LINC 4 study enrolled patients with persistent or recurrent Cushing’s disease or those with de novo disease who were ineligible for surgery; 73 randomised patients were treated with Isturisa® (n=48) or placebo (n=25).1 The primary endpoint of the study is the proportion of randomised patients with a complete response (mUFC ≤ULN) at the end of the placebo-controlled period (week 12). The key secondary endpoint is the proportion of patients with an mUFC ≤ULN at week 36.1,9

About Isturisa®
Isturisa® is an oral inhibitor of 11β-hydroxylase (CYP11B1), which catalyses the final step of cortisol synthesis in the adrenal glands.2 Isturisa® is available as 1 mg, 5 mg and 10 mg film-coated tablets.2 Isturisa® is approved for the treatment of adult patients with endogenous Cushing’s syndrome in the EU and is now available in France, Germany, Greece and Austria.2

Isturisa® was granted marketing authorisation by the European Commission on 9 January 2020. For detailed recommendations on the appropriate use of this product, please consult the summary of product characteristics.2


1. Gadelha M, Bex M, Feelders RA et al. Randomised trial of osilodrostat for the treatment of Cushing’s disease. J Clin Endocrinol Metab 2022; dgac178,
2. Isturisa® summary of product characteristics. May 2020.
3. Ferriere A, Tabarin A. Cushing’s syndrome: Treatment and new therapeutic approaches. Best Pract Res Clin Endocrinol Metab 2020;34:101381.
4. Pivonello R, Fleseriu M, Newell-Price J et al. Efficacy and safety of osilodrostat in patients with Cushing’s disease (LINC 3): a multicentre phase III study with a double-blind, randomised withdrawal phase. Lancet Diabetes Endocrinol 2020;8:748-61.
5. Lacroix A, Feelders RA, Stratakis CA et al. Cushing’s syndrome. Lancet 2015;386:913-27.
6. Pivonello R, Isidori AM, De Martino MC et al. Complications of Cushing’s syndrome: state of the art. Lancet Diabetes Endocrinol 2016;4:611-29.
7. Rubinstein G, Osswald A, Hoster E et al. Time to diagnosis in Cushing’s syndrome: A meta-analysis based on 5367 patients. J Clin Endocrinol Metab 2020;105:dgz136.
8. Nieman LK, Biller BM, Findling JW et al. Treatment of Cushing’s syndrome: An Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2015;100:2807-31.
9. NCT02697734; available at (accessed March 2021).

Recordati Rare Diseases, the company’s EMEA headquarters are located in Puteaux, France, with global headquarter offices in Milan, Italy.

For a full list of products, please click here:

Recordati, established in 1926, is an international pharmaceutical group, listed on the Italian Stock Exchange (Reuters RECI.MI, Bloomberg REC IM, ISIN IT 0003828271), with a total staff of more than 4,300, dedicated to the research, development, manufacturing and marketing of pharmaceuticals. Headquartered in Milan, Italy, Recordati has operations in Europe, Russia and the other C.I.S. countries, Ukraine, Turkey, North Africa, the United States of America, Canada, Mexico, some South American countries, Japan and Australia. An efficient field force of medical representatives promotes a wide range of innovative pharmaceuticals, both proprietary and under license, in several therapeutic areas including a specialized business dedicated to treatments for rare diseases. Recordati is a partner of choice for new product licenses for its territories. Recordati is committed to the research and development of new specialties with a focus on treatments for rare diseases. Consolidated revenue for 2021 was € 1,580.1 million, operating income was € 490.2 million and net income was € 386.0 million.

For further information:

Recordati website:

This document contains forward-looking statements relating to future events and future operating, economic and financial results of the Recordati group. By their nature, forward-looking statements involve risk and uncertainty because they depend on the occurrence of future events and circumstances. Actual results may therefore differ materially from those forecast as a result of a variety of reasons, most of which are beyond the Recordati group’s control. The information on the pharmaceutical specialties and other products of the Recordati group contained in this document is intended solely as information on the Recordati group’s activities and therefore, as such, it is not intended as medical scientific indication or recommendation, nor as advertising.

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Celine Plisson, MD
Medical Affairs Director
Telephone: +33(0)147739463

Assessment of Vitamin D Metabolism in Patients with Cushing’s Disease

Endocrinology Research Centre, 117292 Moscow, Russia
Author to whom correspondence should be addressed.
Academic Editor: Spyridon N. Karras
Nutrients 202113(12), 4329;
Received: 12 November 2021 / Revised: 26 November 2021 / Accepted: 27 November 2021 / Published: 30 November 2021


In this study we aimed to assess vitamin D metabolism in patients with Cushing’s disease (CD) compared to healthy individuals in the setting of bolus cholecalciferol treatment. The study group included 30 adults with active CD and the control group included 30 apparently healthy adults with similar age, sex and BMI. All participants received a single dose (150,000 IU) of cholecalciferol aqueous solution orally. Laboratory assessments including serum vitamin D metabolites (25(OH)D3, 25(OH)D2, 1,25(OH)2D3, 3-epi-25(OH)D3 and 24,25(OH)2D3), free 25(OH)D, vitamin D-binding protein (DBP) and parathyroid hormone (PTH) as well as serum and urine biochemical parameters were performed before the intake and on Days 1, 3 and 7 after the administration. All data were analyzed with non-parametric statistics. Patients with CD had similar to healthy controls 25(OH)D3 levels (p > 0.05) and higher 25(OH)D3/24,25(OH)2D3 ratios (p < 0.05) throughout the study. They also had lower baseline free 25(OH)D levels (p < 0.05) despite similar DBP levels (p > 0.05) and lower albumin levels (p < 0.05); 24-h urinary free cortisol showed significant correlation with baseline 25(OH)D3/24,25(OH)2D3 ratio (r = 0.36, p < 0.05). The increase in 25(OH)D3 after cholecalciferol intake was similar in obese and non-obese states and lacked correlation with BMI (p > 0.05) among patients with CD, as opposed to the control group. Overall, patients with CD have a consistently higher 25(OH)D3/24,25(OH)2D3 ratio, which is indicative of a decrease in 24-hydroxylase activity. This altered activity of the principal vitamin D catabolism might influence the effectiveness of cholecalciferol treatment. The observed difference in baseline free 25(OH)D levels is not entirely clear and requires further study.

1. Introduction

Cushing’s disease (CD) is one of the disorders associated with endogenous hypercortisolism and is caused by adrenocorticotropic hormone (ACTH) hyperproduction originating from pituitary adenoma [1]. Skeletal fragility is a frequent complication of endogenous hypercortisolism, and fragility fractures may be the presenting clinical feature of disease. The prevalence of osteoporosis in endogenous hypercortisolism as assessed by dual-energy X-ray absorptiometry (DXA) or incidence of fragility fractures has been reported to be up to 50%. Osteoporosis in CD patients has a complex multifactorial pathogenesis, characterized by a low bone turnover and severe suppression of bone formation [2]. Exogenous glucocorticoids are used in the treatment of a wide range of diseases and it is estimated that 1–2% of the population is receiving long-term glucocorticoid therapy. As a consequence, glucocorticoid-induced osteoporosis is the most common secondary cause of osteoporosis [3].
Native vitamin D (in particular D3, or cholecalciferol) and its active metabolites (such as alfacalcidol) are universally considered as the essential components of the osteoporosis management [4,5]. The search for the optimal treatment of bone complications during chronic exposure to glucocorticoid excess provoked the investigation of vitamin D metabolism in this state. Early studies on this topic were focused predominantly on the general vitamin D status (assessed as 25(OH)D level) and on the levels of the active vitamin D metabolite (1,25(OH)2D). These studies showed inconsistent results, reporting that the chronic excess of glucocorticoids decreased [6,7,8,9], increased [10,11,12] or did not change [13,14,15] the levels of 25(OH)D or 1,25(OH)2D. A likely reason for such inconsistency might have been the high heterogeneity of the studied groups. Some of these studies were performed in humans [6,7,9,10,11,12,13,15] and some in animal models [8,14], and only several of them included subjects with specifically endogenous hypercortisolism [10,12,14,15]. Only two studies assessed both the levels of the active (1,25(OH)2D) and the inactive (24,25(OH)2D) vitamin D metabolites in endogenous hypercortisolism. One of them lacked control group and reported low-normal 24,25(OH)2D levels in patients with Cushing’s syndrome [10]. The second study by Corbee et al. reported similar circulating concentrations of 25(OH)D, 1,25(OH)2D and 24,25(OH)2D in studied groups of dogs regardless of either the presence of CD or hypophysectomy status [14].
Several experimental studies were performed to evaluate the impact of glucocorticoid excess on the enzymes involved in vitamin D metabolism. In mouse kidney glucocorticoid treatment increased 24-hydroxylase expression [16] and 24-hydroxylase activity [17]. An increased expression of 24-hydroxylase was also shown in rat osteoblastic and pig renal cell cultures treated with 1,25(OH)2D [18]. Dhawan and Christakos showed that 1,25(OH)2D-induced transcription of 24-hydroxylase was glucocorticoid receptor-dependent [19]. However, some works showed conflicting results. In particular, the steroid and xenobiotic receptor (SXR) which is activated by glucocorticoids [20], repressed 24-hydroxylase expression in human liver and intestine in work by Zhou et al. [21]. Lower 24-hydroxylase expression was observed in the brain and myocardium of glucocorticoid-treated rats [22] as well as in human osteosarcoma cells and human osteoblasts [23].
Nevertheless, based on experimental data, it has been suggested that the acceleration of 25(OH)D catabolism in the presence of glucocorticoid excess may predispose to vitamin D deficiency. Yet, relatively recent meta-analysis of the studies assessing 25(OH)D levels in chronic glucocorticoid users showed that serum 25(OH)D levels in these patients were suboptimal and lower than in healthy controls, but similar to steroid-naive disease controls [24].
Glucocorticoids also affect calcium and phosphorus homeostasis. In particular, they were shown to reduce gastrointestinal absorption by antagonizing vitamin D action (reducing the expression of genes for proteins involved in calcium transport—epithelial Ca channel TRPV6 and calcium-binding protein calbindin-D9K) [25]. Glucocorticoids increased fractional calcium excretion due to mineralocorticoid receptor-mediated action on epithelial sodium channels [26]. Hypercalciuria is highly prevalent in people with CD [27]. These effects might result in a negative calcium balance, although plasma ionized calcium was normal in people and dogs with hypercortisolism compared to control subjects [12,28]. Glucocorticoids also reduced tubular phosphate reabsorption by inhibiting tubular expression of the sodium gradient-dependent phosphate transporter, and induced phosphaturia [29], which was accompanied by phosphate lowering in humans [12].
Overall, current data on vitamin D status in hypercortisolism are conflicting and need clarification. In particular, clinical data on the state of vitamin D metabolism in the state of glucocorticoids excess are quite scarce. Studies were very heterogeneous in design, some lacked a control group, and the absolute majority of the studies were performed before the introduction of vitamin D measurement standardization [30]. Nevertheless, determining the optimal vitamin D treatment regimen in these high-risk patients is fairly relevant.
The aim of this study was to assess vitamin D metabolism in patients with CD compared to healthy individuals particularly in the setting of cholecalciferol treatment.

2. Materials and Methods

2.1. Study Population and Design

The study group included 30 adult patients with CD admitted for inpatient treatment at a tertiary pituitary center. Diagnosis of CD was established in accordance with the federal guidelines [31]. All patients were confirmed to be positive for endogenous hypercortisolism in at least two of the following tests: 24-h urine free cortisol (UFC) greater than the normal range for the assay and/or serum cortisol > 50 nmol/L after the 1-mg overnight dexamethasone suppression test and/or late-night salivary cortisol greater than 9.4 nmol/L). All patients also had morning ACTH ≥ 10 pg/mL and pituitary adenoma ≥ 6 mm identified by magnetic resonance imaging (MRI) or a positive for CD bilateral inferior petrosal sinus sampling (BIPSS). MRI was performed using a GE Optima MR450w 1.5T with Gadolinium (Boston, MA, USA). BIPSS was performed according to the standard procedure described elsewhere [32,33].
The control group included 30 apparently healthy adult individuals recruited from the staff and the faculty of the facility.
Inclusion criteria were age from 18 to 60 for both groups and the presence of the disease activity for the study group (defined as the presence of endogenous hypercortisolism at the time of participation in the study). Exclusion criteria for both groups were: vitamin D supplementation for 3 months prior to the study; severe obesity (body mass index (BMI) ≥ 35 kg/m2); pregnancy; the presence of granulomatous disease, malabsorption syndrome, liver failure; decreased GFR (less than 60 mL/min per 1.73 m2); severe hypercalcemia (total serum calcium > 3.0 mmol/L); allergic reactions to vitamin D medications; 25(OH)D level more than 60 ng/mL (determined by immunochemiluminescence analysis). All patients were recruited in the period from October 2019 to April 2021. The study protocol ( Identifier: NCT04844164) was approved by the Ethics Committee of Endocrinology Research Centre, Moscow, Russia on 10 April 2019 (abstract of record No. 6), all patients signed informed consent to participate in the study.
All participants received standard therapeutic dose (150,000 IU) of an aqueous solution of cholecalciferol (Aquadetrim®, Medana Pharma S.A., Sieradz, Poland) orally as a single dose [34]. Blood and urine samples were obtained before the intake as well as on days 1, 3 and 7 after administration; time points of sample collection were determined based on the authors’ previous work evaluating changes in 25(OH)D levels after a therapeutic dose of cholecalciferol [35]. The assessment included serum biochemical parameters (total calcium, albumin, phosphorus, creatinine, magnesium), parathyroid hormone (PTH), vitamin D-binding protein (DBP), vitamin D metabolites (25(OH)D3, 25(OH)D2, 1,25(OH)2D3, 3-epi-25(OH)D3 and 24,25(OH)2D3), free 25(OH)D and urine biochemical parameters (calcium- and phosphorus-creatinine ratios in spot urine).

2.2. Socio–Demographic and Anthropometric Data Collection

At the baseline visit, patients underwent a questionnaire aimed to assess their lifestyle: the presence of unhealthy habits, physical activity level, balanced diet (consumption of dairy products, meat, coffee, soft drinks), exposure to ultraviolet (UV) radiation (solarium and sunscreen usage, traveling south and the number of daytime walks in the sunny weather in the 3 months preceding study participation). Smoking status was classified as current smoker, former smoker and non-smoker; current and former smokers were collectively referred to as total smokers. A unit of alcohol was defined as a glass of wine, a bottle of beer or a shot of spirits, approximating 10–12 g ethanol. Serving of dairy products was defined as 100 g of cottage cheese, 200 mL of milk, 125 g of yogurt or 30 g of cheese. Patients’ weight was measured in light indoor clothing with a medical scale to the nearest 100 g, and their height with a wall-mounted stadiometer to the nearest centimeter. BMI was calculated as weight in kilograms divided by height in meters squared.

2.3. Laboratory Measurements

Morning ACTH (reference range 7–66 pg/mL), serum cortisol after a low-dose dexamethasone suppression test (cutoff value for suppression, 50 nmol/L [36]), late-night salivary cortisol (reference range 0.5–9.4 nmol/L [37]) were assayed by electrochemiluminescence assay using a Cobas 6000 Module e601 (Roche, Rotkreuz, Switzerland). The 24-h UFC (reference range 60–413 nmol/24 h) was measured by an immunochemiluminescence assay (extraction with diethyl ether) on a Vitros ECiQ (Ortho Clinical Diagnostics, Raritan, NJ, USA).
Total 25(OH)D levels (25(OH)D2 + 25(OH)D3; reference range 30–100 ng/mL) at the baseline visit were determined by the immunochemiluminescence analysis (Liaison, DiaSorin, Saluggia, Italy). PTH levels were evaluated by the electrochemiluminescence immunoassay (ELECSYS, Roche, Basel, Switzerland; reference range for this and subsequent laboratory parameters are given in the Results section for easier reading). Biochemical parameters of blood serum and urine were assessed by the ARCHITECT c8000 analyzer (Abbott, Chicago, IL, USA) using reagents from the same manufacturer according to the standard methods. Serum DBP and free 25(OH)D levels were measured by enzyme-linked immunosorbent assay (ELISA) using commercial kits. The assay used for free 25(OH)D levels assessment (DIAsource, ImmunoAssays S.A., Ottignies-Louvain-la-Neuve, Belgium) has <6.2% intra- and inter-assay coefficient of variation (CV) at levels 5.8–9.6 pg/mL. The assay used for DBP levels assessment (Assaypro, St Charles, MO, USA) has 6.2% average intra-assay CV and 9.9% average inter-assay CV.
The levels of vitamin D metabolites (25(OH)D3, 25(OH)D2, 1,25(OH)2D3, 3-epi-25(OH)D3 and 24,25(OH)2D3) in serum were determined by ultra-high performance liquid chromatography in combination with tandem mass spectrometry (UPLC-MS/MS) using an in-house developed method, described earlier [38]. With this technique, the laboratory participates in DEQAS quality assurance program (lab code 2388) and the results fall within the target range for the analysis of 25(OH)D and 1,25(OH)2D metabolites in human serum (Supporting Information, Figures S1 and S2). All UPLC-MS/MS measurements were made after the first successful completion (5/5 samples within the target range) of the DEQAS distributions for both analytes simultaneously. Each batch contained control samples (analytes in blank serum) with both high and low analyte concentrations. The samples were barcoded and randomized prior to the measurements to eliminate analyst-related errors.
Serum samples (3 aliquots) collected at each visit were either transferred directly to the laboratory for biochemical analyzes, total 25(OH)D and PTH measurement (1 aliquot) or were stored at −80 °C avoiding repeated freeze-thaw cycles for measurement of DBP, free 25(OH)D and vitamin D metabolites at a later date (2 aliquots).
Albumin-adjusted serum calcium levels were calculated using the formula [39]: total plasma calcium (mmol/L) = measured total plasma calcium (mmol/L) + 0.02 × (40 − measured plasma albumin (g/L)).
Baseline free 25(OH)D levels were also calculated using the formula introduced by Bikle et al. [40,41]. The affinity constant for 25(OH)D and albumin binding (Kalb) used for the calculation was equal 6 × 105 M−1, and affinity constant for 25(OH)D and DBP binding (KDBP) was equal 7 × 108 M−1.

Free 25(OH)D=total 25(OH)D1+Kalbalbumin+KDBPDBP

2.4. Statistical Analysis

Statistical analysis was performed using Statistica version 13.0 (StatSoft, Tulsa, OK, USA). All data were analyzed with non-parametric statistics and expressed as median [interquartile range] unless otherwise specified. Mann-Whitney U-test and Fisher’s exact two-tailed test were used for comparisons between two groups. Friedman ANOVA was performed to evaluate changes in indices throughout the study and pairwise comparisons using Wilcoxon test with adjustment for multiple comparisons (Bonferroni) were also made if the Friedman ANOVA was significant. Spearman rank correlation method was used to obtain correlation coefficients among indices. A p-value of less than 0.05 was considered statistically significant. When adjusting for multiple comparisons, a p-value greater than the significance threshold, but less than 0.05 was considered as a trend towards statistical significance.

3. Results

The groups were similar in terms of age, sex and BMI (p > 0.05). Both groups consisted predominantly of young and middle-aged women and the majority of patients were overweight or moderately obese (Table 1). Patients from the study group presented with lower screening levels of total 25(OH)D (p < 0.05).
Table 1. General characteristics of the patients at the baseline visits. For detailed description of the data format please refer to the Section 2.
The features of the underlying disease course in the study group are listed in Table 2. 15 patients (50%) had diabetes mellitus with an almost compensated state at the time of participation in the study, and 7 patients (23%) reported a history of low-energy fractures.
Table 2. Characteristics of the patients with Cushing’s disease (CD) in terms of the underlying disease.
The groups did not differ significantly in the reported smoking status, the level of daily physical activity, dietary habits and UV exposure (p > 0.05) and although there was a slight difference in alcohol consumption (p < 0.05), the absolute values were minor in both groups (Table 3).
Table 3. Questionnaire results.

3.1. Baseline Laboratory Evaluation

Detailed results of laboratory studies are presented in Table 4 and Table 5.
Table 4. Changes in the levels of the biochemical parameters and parathyroid hormone (PTH) during the study.
Table 5. Changes in the levels of free 25(OH)D, vitamin D-binding protein (DBP) and vitamin D metabolites during the study.
Patients with CD had several alterations in biochemical parameters, in particular, lower baseline serum creatinine and albumin levels, while magnesium levels were higher than in the control group (p < 0.05). They also had higher levels of urine phosphorus-creatinine ratio (p < 0.05). The rest of the studied biochemical parameters did not show significant difference between the groups (p > 0.05). 3 patients (10%) from the study group and 5 patients (17%) from the control group had secondary hyperparathyroidism, one patient with CD (3%) was diagnosed with mild primary hyperparathyroidism.
As for the assessment of vitamin D metabolism, unexpectedly the levels of 25(OH)D3 occurred to be equal in the groups (p > 0.05), with only two patients (7%) from the study group and one patient (3%) from the control group having sufficient vitamin D levels, according to the Endocrine Society and the Russian Association of Endocrinologists guidelines (≥30 ng/mL [34,42]). The levels of the active vitamin D metabolite—1,25(OH)2D3—were equal between the groups as well (p > 0.05), whereas the levels of 3-epi-25(OH)D3 and 24,25(OH)2D3 were lower in CD patients. Further calculation of 25(OH)D3/24,25(OH)2D3 and 25(OH)D3/1,25(OH)2D3 ratios corresponded to the observed levels of metabolites: 25(OH)D3/24,25(OH)2D3 ratio was higher in the study group (p < 0.05) assuming lower 24-hydroxylase activity and 25(OH)D3/1,25(OH)2D3 ratio was equal between the groups (p > 0.05).
Levels of free 25(OH)D were lower in CD patients (p < 0.05) and the levels of DBP did not differ between the groups (p > 0.05). Although calculated free 25(OH)D showed prominent positive correlation with the measured free 25(OH)D in both groups (r = 0.63 in the study group, r = 0.87 in the control group, p < 0.05), the association appeared to be weaker in the study group. In the control group, DBP levels correlated with both measured and calculated 25(OH)D levels (r = −0.48, p < 0.05 and r = −0.69, p < 0.05 respectively), while in patients with CD there was no association with measured free 25(OH)D levels (r = 0.04, p > 0.05 and r = −0.50, p < 0.05 respectively).
Correlation with 24-h UFC in CD patients was observed for serum albumin level (r = −0.37, p < 0.05) and urine calcium-creatinine ratio (r = 0.51, p < 0.05) among assessed biochemical parameters, and only with 25(OH)D3/24,25(OH)2D3 ratio among the parameters of vitamin D metabolism (r = 0.36, p < 0.05).

3.2. Laboratory Evaluation after the Intake of Cholecalciferol

All patients from the study group and 28 patients (93%) from the control group completed the study.
The observed baseline differences in biochemical parameters mostly preserved during the follow-up. In the study group there was an increase in serum phosphorus levels by Day 1 (p = 0.006) and a tendency to an increase in the urine phosphorus-creatinine ratio by Day 7 (p = 0.02). Patients from the control group showed a clinically insignificant increase in serum creatinine levels by Day 1 (p = 0.002) and a non-significant trend towards an increase in serum total and albumin-adjusted calcium (p = 0.01 for both measurements). No change in PTH levels was observed in patients with CD during the follow-up (p > 0.05), while in the control group there was a tendency for PTH to decrease by Day 3 (p = 0.02). There were no new cases of hypercalcemia in both groups during the follow-up. One patient from the study group and one patient from the control group had persistently increased urine calcium-creatinine ratio throughout the study. Four patients from the study group (13%) and none from the control group developed hypercalciuria during the follow-up, however these patients had no clinical manifestations during the observation period.
By Day 7, 25 patients (83%) from the study group and 22 patients (79%) reached sufficient 25(OH)D3 levels (≥30 ng/mL). Levels of 25(OH)D3 continued to increase by Day 3 in both groups (p < 0.001), after which tended to decrease in the study group (p = 0.01) and remained stable in the control group (p = 0.65). The increase in 25(OH)D3 after cholecalciferol intake was equal between the groups (18.5 [15.9; 22.5] ng/mL in the study group vs. 16.6 [13.1; 19.8] ng/mL in the control group, p > 0.05). In the presence of obesity, Δ25(OH)D3 was higher in the CD patients than in the control group (18.3 [14.2; 23.0] vs. 12.1 [10.0; 13.1] ng/mL, p < 0.05), while in non-obese patients no difference was observed (p > 0.05).
Obese and non-obese patients with CD had equal Δ25(OH)D3 (18.3 [14.2; 23.0] vs. 19.6 [16.0; 21.5] ng/mL, p > 0.05), while in the control group it was significantly lower in obese patients (12.1 [10.0; 13.1] vs. 18.3 [15.3; 21.4] ng/mL, p < 0.05). BMI showed significant correlation with Δ25(OH)D3 only in the control group (r = −0.47, p < 0.05), while in CD patients there was no such association (r = −0.06, p > 0.05) (Figure 1).
Figure 1. Relationship between Δ25(OH)D3 and BMI in groups.
1,25(OH)2D3 levels increased in CD patients by Day 1 and were stable during the follow-up in the control group. The rest of the studied parameters of vitamin D metabolism changed in a similar way between groups: 3-epi-25(OH)D3 levels increased until the Day 3, after which they decreased by the Day 7; 24,25(OH)2D3 levels showed more graduate elevation throughout the follow-up. In both groups 25(OH)D3/24,25(OH)2D3 ratios increased by Day 1, after which they decreased by Day 7, and 25(OH)D3/1,25(OH)2D3 ratios increased by Day 1, after which they remained stable. DBP levels didn’t change and free 25(OH)D levels showed an increase in both groups during the follow-up. The levels of 25(OH)D2 did not exceed 0.5 ng/mL in all examined individuals throughout the study. Among assessed parameters of vitamin D metabolism, higher 25(OH)D3/24,25(OH)2D3 ratios in the study group was the only difference between the groups which remained significant throughout the observation period (p < 0.05) (Figure 2).
Figure 2. Dynamic evaluation of 25(OH)D3/24,25(OH)2D3 ratios in groups.

4. Discussion

The main goal of our study was to evaluate the 25(OH)D3 levels and its response to the therapeutic dose of cholecalciferol in patients with CD as compared to healthy individuals. We observed no difference in baseline 25(OH)D3 assessed by UPLC-MS/MS between groups. Similar to our data were obtained in most studies conducted specifically in the state of endogenous hypercortisolism in humans [12,15] and dogs [14]. The study by Kugai et al. lacked control group and reported plasma levels of 25(OH)D corresponding to the vitamin D deficiency in most of the examined patients [10], while in our study only 2/3 of the patients with CD had 25(OH)D levels below 20 ng/mL. As for exogenous hypercortisolism, the meta-analysis aimed to explore serum 25(OH)D levels in glucocorticoid users showed lower levels than in healthy controls, but similar to steroid-naive disease controls, thus causing concern regarding the influence of the disease status on 25(OH)D levels [24]. Somewhat surprisingly, we obtained significantly discordant results in the study group when screening total 25(OH)D by ELISA and when measuring baseline 25(OH)D3 by UPLC-MS/MS, since the initial difference between the groups revealed by ELISA data with lower total 25(OH)D levels in the study group was not replicated by UPLC-MS/MS. It should be noted that our ELISA method did not participate in an external quality control program at the time of the study unlike UPLC-MS/MS; furthermore, a lower analytical performance was previously described for this technique with tendency for low specificity and lower measurement results [45].
When assessing other parameters of vitamin D metabolism, the most significant finding was the higher 25(OH)D3/24,25(OH)2D3 ratio in CD patients, both initially and during the observation after the intake of the cholecalciferol loading dose, indicating consistently reduced activity of 24-hydroxylase, the main enzyme of vitamin D catabolism. Earlier clinical and experimental studies also suggested altered activity of enzymes of vitamin D metabolism in hypercortisolism. However, these studies were heterogeneous and aimed predominantly at studying the activity of 1α-hydroxylase [7,8,10,11,12,14], which was not altered in patients with CD as compared to healthy individuals in our study. In the setting of the short-term glucocorticoid administration, Lindgren et al. showed transient increase in 24,25(OH)2D3 levels in rats [8], while in the study of Hahn et al. there was no change in 24,25(OH)2D3 levels [11]. Dogs with CD had similar 24,25(OH)2D3 levels before and after hypophysectomy as well as compared to control dogs [14]. The only study of considerably similar design by Kugai et al. reported low-normal 24,25(OH)2D3 in patients with Cushing’s syndrome [10], which is consistent with our result, as well as some experimental works indicative of suppression on CYP24A1 expression by glucocorticoids in human osteoblasts [23], liver and intestine [21] and in rat brain and myocardium [22]. However, in the present work, the activity of 24-hydroxylase in patients with hypercortisolism was for the first time evaluated by calculating the 25(OH)D3/24,25(OH)2D3 ratio, which has recently emerged as a new tool for vitamin D status assessment [46,47]. Given the correlation of this parameter with laboratory marker of the underlying disease activity (24-h UFC), a direct effect of cortisol overproduction on 24-hydroxylase activity might be assumed. Interestingly, it seems that the decreased activity of 24-hydroxylase observed in CD influenced the effectiveness of cholecalciferol treatment, decreasing the negative effect of obesity, as patients with CD had similar increase in 25(OH)D3 in obese and non-obese state and lacked correlation between Δ25(OH)D3 and BMI, as opposed to the control group. Moreover, the increase in 25(OH)D3 in obese patients from the control group was lower not only than in non-obese controls, but also than in obese patients with CD.
Another intriguing finding was lower levels of free 25(OH)D observed in patients with CD despite similar DBP levels and lower albumin levels, which, on the contrary, allows one to expect higher values of free 25(OH)D. Considering the weaker correlation between the measured and calculated free 25(OH)D in patients with CD, as well as the lack of correlation of the measured 25(OH)D with the main transport protein, an altered affinity of DBP might be suspected. One possible explanation is protein glycosylation as a consequence of diabetes mellitus, which was present in half of the patients [38,48,49]. After cholecalciferol intake, which was accompanied by an increase in free 25(OH)D, the differences between the groups were leveled; therefore, another suggested explanation might be competitive binding to the ligand. Since actin binds DBP with high affinity [50] and considering catabolic action of glucocorticoids on muscle tissue [51], actin is a presumable competing ligand candidate. Although this is mostly speculative, as far as the authors are aware, the present work was the first to assess free vitamin D in the glucocorticoid excess, so the described findings require verification of reproducibility and further evaluation.
The obtained discrepancies in the biochemical parameters characterizing calcium and phosphorus metabolism were generally consistent with the data of early studies discussed in the introduction [12,25,26,27,28,29], except for similar to controls serum phosphorus levels and lower prevalence of hypercalciuria. An interesting observation was the complete absence of the PTH decrease in patients with CD after receiving a loading dose of cholecalciferol. The mechanism of this phenomenon is not entirely clear, we tend to agree with the earlier hypothesis that this may be an adaptation to chronic urinary calcium loss [52].
Our research is distinguished by a number of important strengths: a prospective design, substantial sample of patients with CD, accounting for social and behavioral factors affecting vitamin levels D, comprehensive spectrum of vitamin D metabolism parameters investigated and participation in an external quality control program for vitamin D metabolites measurement.
Nevertheless, the study also had several limitations: the amount of dietary vitamin D and phosphorus, as well as possible differences in DBP affinity to vitamin D metabolites due to genetic isoforms of DBP [53] or other possible involved parameters (e.g., fibroblast growth factor-23) were not taken into account. A few patients from both groups received therapy with possible impact on vitamin D and calcium metabolism within 3 months preceding the participation in the study (spironolactone, diuretics, proton pump inhibitors, oral contraceptives, antifungal treatment, antidepressants, barbiturates, antiepileptic drugs). The groups had a trend for differences in sex and BMI (p = 0.07 for both parameters). Also, the study lacked a study group of patients with remission of CD to test the hypotheses put forward, however, this is a promising direction for further research.

5. Conclusions

We report that patients with endogenous ACTH-dependent hypercortisolism of pituitary origin have a consistently higher 25(OH)D3/24,25(OH)2D3 ratio than healthy controls, which is indicative of a decrease in 24-hydroxylase activity. This altered activity of the principal vitamin D catabolism might influence the effectiveness of cholecalciferol treatment. There is also a lack of clarity regarding the lower levels of free 25(OH)D observed in patients with CD, which require further study. To test the proposed hypotheses and to develop specialized clinical guidelines for these patients, longer-term randomized clinical trials are needed.

Supplementary Materials

The following are available online at, Method validation against DEQAS, Figure S1: Comparison between DEQAS data for 25(OH)D scheme and our lab results, Figure S2: Comparison between DEQAS data for 1,25(OH)2D scheme and our lab results.

Author Contributions

Conceptualization, L.R., E.P., A.P. and A.Z.; methodology, V.B., Z.B., L.R. and G.M.; formal analysis, A.P.; investigation, A.P., V.B., E.P., L.D. and A.Z.; data curation, A.P. and V.B.; writing—original draft preparation, A.P.; writing—review and editing, V.B., E.P., A.Z., Z.B., L.R.; visualization, V.B.; supervision, L.D., L.R., G.M. and N.M.; project administration, L.R. and N.M.; funding acquisition, L.R. and N.M. All authors have read and agreed to the published version of the manuscript.


This research was funded by the Russian Science Foundation, grant number 19-15-00243.

Institutional Review Board Statement

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Endocrinology Research Centre, Moscow, Russia on 10 April 2019 (abstract of record No. 6).

Informed Consent Statement

Written informed consent was obtained from all individual participants included in the study.

Data Availability Statement

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.


We express our deep gratitude to our colleagues: Natalya M. Malysheva, Vitaliy A. Ioutsi, Larisa V. Nikankina for the help with the laboratory research.

Conflicts of Interest

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.


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Sparrow Pharmaceuticals Hopes To Change The Future Of Endocrinology

By Ed Miseta, Chief Editor, Clinical Leader
Follow Me On Twitter @EdClinical

Go ahead and continuously improvement iStock-1295289697

Sparrow Pharmaceuticals is an emerging biopharma company on a mission to help patients suffering from an excess of corticosteroids, with a focus on Cushing’s syndrome, autonomous cortisol secretion (ACS), and polymyalgia rheumatica (PMR).

Cushing’s and ACS are both caused by an excess of cortisol produced by tumors. Patients with Cushing’s can present physically with a fatty hump between their shoulders, a rounded face, and pink or purple stretch marks on their skin. Cushing’s syndrome and ACS can both result in high blood pressure, bone loss, type 2 diabetes, weight gain, and mood, cognition, and sleep disorders. Any of those symptoms may be side effects for patients with conditions such as PMR who rely on long-term treatment with corticosteroid medications such as prednisone.

“Cushing’s syndrome impacts around 20,000 patients in the U.S. alone,” says David Katz, Chief Scientific Officer for Sparrow. “Approximately 50% of those patients can be cured by surgery, but some will develop another tumor years later. ACS is an under-recognized condition, but it may affect up to 3 million patients in the U.S. There are also around 2 million people in the U.S. who rely on long-term use of corticosteroid medications to control autoimmune diseases and other conditions.”

The treatments being developed by Sparrow are based on recognition that cortisol and corticosteroid medications are activated in certain tissues such as the liver, bone, fat, and brain, where in excess they act to cause toxicity. The company’s investigational drugs inhibit HSD-1, the enzyme responsible for that activation.

Sparrow is about to launch a Phase 2 trial for Cushing’s syndrome. In early 2022 the company will also begin two additional Phase 2 trials for ACS and PMR, a common autoimmune disease in elderly patients. PMR is an arthritic syndrome characterized by a phenomenon known as claudication, which means the more you use a limb, the more it hurts and the harder it is to use. “For example, the more a PMR patient walks, the more painful and stiff their legs will become,” says Katz. “If they’re trying to do anything with their arms, the arms will get stiffer and more painful. The disease is pretty debilitating in terms of physical function. The only approved treatment for PMR is steroids, which have side effects such as diabetes, hypertension, osteoporosis, and fractures.”

Unknown Clinical Challenges

Katz is excited about the clinical trials for ACS and PMR because no sizable interventional trials have been reported in either of those conditions.

“We’re going into a completely new area, and we don’t know what we’re going to encounter in terms of patient recruitment and retention,” says Katz. “There is also no strong precedent for how to get approval for a drug in these conditions. The only treatment indicated for PMR is steroids, and that came without any efficacy clinical trials. There are no drugs approved for ACS. It’s hard to anticipate the challenges we will face when we are in an area that is very new.”

Patient centricity is a topic that is very important to Katz, and he spends a lot of time thinking about how to make trials a more pleasant experience for patients by limiting the burden placed on them. He notes that can sometimes be a difficult trade-off because of the procedures that must be performed to meet regulatory standards.

“In Cushing’s syndrome clinical care and clinical trials, the standard way for someone’s cortisol level to be measured is a 24-hour urine collection,” states Katz. “That involves looking at the amount of cortisol in the urine over a 24-hour period. That collection is inconvenient and burdensome, and the patient must then carry it somewhere to be analyzed.”

Sparrow hopes to shift that collection to a spot urine sample, like what patients would experience during a physical. The patient would urinate into a cup and hand it off to a clinic employee for analysis. The process would be much simpler and less burdensome for the patient. Sparrow will first need to prove that in a clinical trial the spot sample will work as well or better than the 24-hour collection. Subjects in the initial clinical trials will have to contribute the 24-hour collections so that Sparrow can demonstrate that future patients will not need to do so.

The Future of Endocrinology

Katz has a positive outlook on the future of endocrinology. Sparrow’s leading drug candidate, SPI-62, is an oral, small-molecule HSD-1 inhibitor. In four clinical trials, it demonstrated potent targeting of HSD-1 in both the brain and liver, and significantly lowered cortisol levels in the liver. The studies also showed a favorable safety and tolerability profile.

“If we are successful at developing SPI-62, I believe it will change the field of endocrinology,” says Katz. “We aim to shift the focus in Cushing’s syndrome to intracellular cortisol as the main driver of symptoms. What I mean by that is if we find that SPI-62 substantially reduces symptoms and that the degree of inhibition of our target HSD-1 correlates well with clinical improvement, then we can get to a new standard of care. We can potentially get rid of the 24-hour urine collections, which will be a big relief to patients. Additionally, many of today’s drugs have a side effect called adrenal insufficiency, which results when the drugs either reduce cortisol too much or completely block activity. Many of today’s drugs also require frequent monitoring and dose titration to prevent adrenal insufficiency. We believe that with HSD-1 inhibition we might avoid adrenal insufficiency as well.”

Katz is hopeful patients treated with SPI-62 will not require monitoring and dose titration. That proof will take years and lots of clinical trials. Sparrow may also produce the first targeted therapy for ACS. That could improve the recognition of ACS as a prevalent form of hypercortisolism and a substantial cause of morbidity and mortality.

“ACS is probably the most under-recognized condition in endocrinology based on recent epidemiological studies,” adds Katz. “It’s possible that as few as 3% of patients who have ACS actually have a diagnosis.  That is shocking for a condition that is associated with a lot of cardiometabolic and bone morbidity, negative effects on mood and cognition, sleep, and muscle strength, and is associated with excess mortality. We want to bring attention to this condition by bringing out a targeted therapy to treat a spectrum of symptoms by getting to the root cause of them.”


New Drug Application for RECORLEV® (levoketoconazole) for the Treatment of Endogenous Cushing’s Syndrome

~ RECORLEV® (levoketoconazole) New Drug Application is Supported by Previously-Reported Positive and Statistically Significant Results from the Phase 3 SONICS and LOGICS Studies ~

~ Nearly 40 Percent of Prescription-Treated Endogenous Cushing’s Syndrome Patients in the U.S. Are Not Well-Controlled, Underscoring Need for New, Safe and Effective Pharmaceutical Options to Help Regulate Cortisol Levels ~

~ If Approved Following a Projected 10-Month Review Cycle, RECORLEV is Anticipated to Launch in First Quarter of 2022 ~

DUBLIN, Ireland and TREVOSE, Pa., March 02, 2021 (GLOBE NEWSWIRE) — Strongbridge Biopharma plc, (Nasdaq: SBBP), a global commercial-stage biopharmaceutical company focused on the development and commercialization of therapies for rare diseases with significant unmet needs, today announced that it submitted a New Drug Application (NDA) for RECORLEV® (levoketoconazole) for the treatment of endogenous Cushing’s syndrome to the U.S. Food and Drug Administration (FDA). The submission is supported by previously reported positive and statistically significant results of the SONICS and LOGICS trials: two Phase 3 multinational studies designed to evaluate the safety and efficacy of RECORLEV when used to treat adults with endogenous Cushing’s syndrome.

“The submission of the New Drug Application for RECORLEV® (levoketoconazole) represents not only a significant milestone for Strongbridge but also for the Cushing’s syndrome community as a whole. As an organization focused on developing treatments for underserved rare disease patient populations, we are one step closer to helping address the needs of the estimated 8,000 Cushing’s syndrome patients in the U.S. who are treated with prescription therapy, many of whom, as we learned in our market research, are not well-controlled with current therapies,” said John H. Johnson, chief executive officer of Strongbridge Biopharma. “We look forward to working with the FDA through their review of our application, and we are actively preparing for the potential launch of RECORLEV in the first quarter of 2022, if approved.”

RECORLEV, the pure 2S,4R enantiomer of the enantiomeric pair comprising ketoconazole, is a next-generation steroidogenesis inhibitor being investigated as a chronic therapy for adults with endogenous Cushing’s syndrome. Two Phase 3 studies have demonstrated substantial evidence of efficacy and safety in a combined study population of 166 patients that was representative of the adult drug-treated U.S. population with Cushing’s syndrome. The SONICS study met its primary and key secondary endpoints, demonstrating a statistically significant rate of mean urinary free cortisol normalization after six months of maintenance therapy without a dose increase (detailed results here). LOGICS, a double-blind, placebo-controlled randomized-withdrawal study, which also had statistically significant primary and key secondary endpoints, confirmed that the long-term cortisol-normalizing efficacy demonstrated in SONICS was due to use of levoketoconazole specifically (detailed results here). The long-term open-label extension study, OPTICS, is contributing safety information to the NDA.

“We want to thank the patients, their families, investigators, collaborators, and employees who have contributed to the RECORLEV clinical program leading to this important regulatory milestone,” said Fredric Cohen, M.D., chief medical officer of Strongbridge Biopharma.

RECORLEV has received orphan drug designation from the FDA and the European Medicines Agency for the treatment of endogenous Cushing’s syndrome.

Strongbridge will host a conference call tomorrow, Wednesday, March 3, 2021 at 8:30 a.m. ET to discuss the Company’s fourth quarter and full-year 2020 financial results and recent corporate highlights, including the RECORLEV NDA submission.

About Cushing’s Syndrome
Endogenous Cushing’s syndrome is a rare, serious and potentially lethal endocrine disease caused by chronic elevated cortisol exposure – often the result of a benign tumor of the pituitary gland. This benign tumor tells the body to overproduce high levels of cortisol for a sustained period of time, and this often results in undesirable physical changes. The disease is most common among adults between the ages of 30 to 50, and it affects women three times more often than men. Women with Cushing’s syndrome may experience a variety of health issues including menstrual problems, difficulty becoming pregnant, excess male hormones (androgens), primarily testosterone which can cause hirsutism (growth of coarse body hair in a male pattern), oily skin, and acne. Additionally, the internal manifestations of the disease are potentially life threatening. These include metabolic changes such as high blood sugar, or diabetes, high blood pressure, high cholesterol, fragility of various tissues including blood vessels, skin, muscle and bone, and psychologic disturbances such as depression, anxiety and insomnia. Untreated, the five-year survival rate is only approximately 50 percent.

About the SONICS Study
SONICS is an open-label, Phase 3 study of RECORLEV as a treatment for endogenous Cushing’s syndrome that enrolled 94 patients at centers in North America, Europe and the Middle East. Following a screening phase, SONICS has three treatment phases: (1) Dose Titration Phase: Patients started RECORLEV at 150 mg twice daily (300 mg total daily dose) and titrated in 150 mg increments with the goal of achieving a therapeutic dose – a dose resulting in mUFC normalization – at which point titration was stopped; (2) Maintenance Phase: The dose was fixed and should not have been changed other than for safety reasons or loss of efficacy. At the end of the six-month maintenance phase, the mUFC response rate was measured; and (3) Extended Evaluation Phase: Patients continued on RECORLEV for another six months to evaluate long-term safety and tolerability and explore efficacy durability.

About the LOGICS Study
The Phase 3, multinational, double-blind, placebo-controlled, randomized-withdrawal study, LOGICS, randomized Cushing’s syndrome patients with baseline mean urinary free cortisol (mUFC) at least 1.5 times the upper limit of normal (ULN) following completion of a single-arm, open-label treatment phase of approximately 14 to 19 weeks, with RECORLEV individually titrated according to mUFC response.

A total of 79 patients were dosed during the open-label titration-maintenance phase, 7 of whom had previously received RECORLEV during the SONICS study, and 72 who had not previously received RECORLEV. At study baseline, the median mUFC was 3.5 times the ULN, indicative of significant hypercortisolemia.

A total of 44 patients (39 who had completed the titration-maintenance phase and five who directly enrolled from the SONICS study), were randomized to either continue RECORLEV (n=22) or to have treatment withdrawn by receiving a matching placebo regimen (n=22) for up to 8 weeks, followed by restoration to the prior regimen using blinded drug. Of the 44 patients randomized, 11 patients (25 percent) had previously received RECORLEV during the SONICS study. Patients who required rescue treatment with open-label RECORLEV during the randomized-withdrawal phase were considered to have lost mUFC response at the visit corresponding to their first dose of rescue medication. Patients who did not qualify for randomization were removed from open-label treatment prior to randomization and excused from the study.

RECORLEV® (levoketoconazole) is an investigational cortisol synthesis inhibitor in development for the treatment of patients with endogenous Cushing’s syndrome, a rare but serious and potentially lethal endocrine disease caused by chronic elevated cortisol exposure. RECORLEV is the pure 2S,4R enantiomer of ketoconazole, a steroidogenesis inhibitor. RECORLEV has demonstrated in two successful Phase 3 studies to significantly suppress serum cortisol and has the potential to be a next-generation cortisol inhibitor.

The Phase 3 program for RECORLEV includes SONICS and LOGICS: two multinational studies designed to evaluate the safety and efficacy of RECORLEV when used to treat endogenous Cushing’s syndrome. The SONICS study met its primary and secondary endpoints, demonstrating a statistically significant normalization rate of urinary free cortisol at six months. The LOGICS study, which met its primary endpoint, is a double-blind, placebo-controlled randomized-withdrawal study of RECORLEV that is designed to supplement the long-term efficacy and safety information supplied by SONICS. The ongoing long-term open label OPTICS study will gather further useful information related to the long-term use of RECORLEV.

RECORLEV has received orphan drug designation from the FDA and the European Medicines Agency for the treatment of endogenous Cushing’s syndrome.

About Strongbridge Biopharma
Strongbridge Biopharma is a global commercial-stage biopharmaceutical company focused on the development and commercialization of therapies for rare diseases with significant unmet needs. Strongbridge’s rare endocrine franchise includes RECORLEV® (levoketoconazole), a cortisol synthesis inhibitor currently being studied in Phase 3 clinical studies for the treatment of endogenous Cushing’s syndrome, and veldoreotide extended release, a pre-clinical next-generation somatostatin analog being investigated for the treatment of acromegaly and potential additional applications in other conditions amenable to somatostatin receptor activation. Both RECORLEV and veldoreotide have received orphan drug designation from the FDA and the European Medicines Agency. The Company’s rare neuromuscular franchise includes KEVEYIS® (dichlorphenamide), the first and only FDA-approved treatment for hyperkalemic, hypokalemic, and related variants of primary periodic paralysis. KEVEYIS has orphan drug exclusivity in the United States.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the federal securities laws. The words “anticipate,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “project,” “target,” “will,” “would,” or the negative of these terms or other similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. All statements, other than statements of historical facts, contained in this press release, are forward-looking statements, including statements related to data from the LOGICS and SONICS studies, the potential advantages of RECORLEV, the anticipated timing for potential approval of a marketing authorization for RECORLEV and for the potential launch of RECORLEVStrongbridge’s strategy, plans, outcomes of product development efforts and objectives of management for future operations. Forward-looking statements involve risks and uncertainties that could cause actual results to differ materially from those expressed in such statement, including risks and uncertainties associated with clinical development and the regulatory approval process, the reproducibility of any reported results showing the benefits of RECORLEV, the adoption of RECORLEV by physicians, if approved, as treatment for any disease and the emergence of unexpected adverse events following regulatory approval and use of the product by patients. Additional risks and uncertainties relating to Strongbridge and its business can be found under the heading “Risk Factors” in Strongbridge’s Annual Report on Form 10-K for the year ended December 31, 2019 and its subsequent Quarterly Reports on Form 10-Q, as well as its other filings with the SEC. These forward-looking statements are based on current expectations, estimates, forecasts and projections and are not guarantees of future performance or development and involve known and unknown risks, uncertainties and other factors. The forward-looking statements contained in this press release are made as of the date of this press release, and Strongbridge Biopharma does not assume any obligation to update any forward-looking statements except as required by applicable law.


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