United States

Tumor-induced Osteomalacia (TIO) is a rare condition in which excess FGF23 produced by a tumor leads to renal phosphate wasting, impaired 1,25(OH)2D synthesis, osteomalacia, fractures, weakness, fatigue, and decreased mobility. In an ongoing open-label Phase 2 study (NCT02304367), 17 adults with TIO or cutaneous skeletal hypophosphatemia syndrome (CSHS) were enrolled and received burosumab, a fully human monoclonal antibody against FGF23. Key endpoints were changes in serum phosphorus and osteomalacia as assessed from trans-iliac crest bone biopsies. This report excludes 3/17 subjects who did not have TIO: 2 subjects diagnosed with X-linked hypophosphatemia post-enrollment and 1 subject with CSHS. Serum phosphorus increased from baseline (BL; 1.60 mg/dL) and was maintained after titration, from Week (W) 22 (2.85 mg/dL, dosing cycle midpoint) to W144 (2.56 mg/dL, dosing cycle endpoint, p&lt;0.0001). Serum TmP/GFR and 1,25(OH)2D also increased with burosumab. Eleven subjects underwent paired bone biopsies at BL and W48. Osteoid volume/bone volume decreased from a mean ± SE of 17.6% ± 5.9% at BL to 12.1% ± 4.7% at W48 (p=0.086). Mean ± SE osteoid thickness decreased from 16.5 ± 3.6 µm to 11.3 ± 2.8 µm (p&lt;0.05). Using imputation (Dempster et al. 2012), mineralization lag time decreased from a mean ± SE of 1598 ± 420 days to 1032 ± 712 days (p=0.41). Osteoid surface/bone surface showed no change from BL (mean ± SE BL: 57% ± 9%, W48: 57% ± 7%). Of 249 areas identified with increased uptake on bone scan at BL, 68 (27%) and 81 (33%) were fully healed at W96 and W144, respectively; 56 (23%) and 32 (13%) were partially healed at W96 and W144, respectively. Mean (SD) Global Fatigue Score decreased from 5.6 (2.5) at BL to 3.5 (3.0) at W48, and to 3.8 (2.2) at W144 (both p&lt;0.01). All 3 domains of the Brief Pain Inventory decreased with burosumab (W144 Pain Severity and Pain Interference p&lt;0.05), indicating reduced pain. The SF-36 mean (SD) physical component summary score increased from 33 (10) at BL to 39 (10) at W48 (p&lt;0.05) and to 41 (12) at W144 (p&lt;0.01), indicating improved physical functioning. The mean (SD) number of sit-to-stand repetitions, an assessment of proximal muscle function, increased from 6.7 (4.2) at BL to 8.5 (4.2) at W48 (n=10; p&lt;0.01). All subjects had ≥1 adverse event (AE). Two subjects discontinued: 1 to undergo chemotherapy to treat an AE of neoplasm progression and 1 failed to meet serum phosphorus dosing criteria and therefore received minimal burosumab dosing. There were 16 serious AEs in 7 subjects, all unrelated to drug. Of the 6 subjects with a serious AE of tumor progression/compression, 5 had a history of tumor progression prior to enrollment. There was 1 death, considered unrelated to treatment. In adults with TIO Syndrome, burosumab was associated with improvements in phosphate metabolism, osteomalacia, skeletal metabolism/fracture healing, physical functioning, fatigue, pain, and quality of life.

ENDO 2020

Burosumab Improves Biochemical, Skeletal, and Clinical Features of Tumor-Induced Osteomalacia Syndrome

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ENDO is the place where leading experts, researchers, and the most respected clinicians in the field come together to share the latest findings in hormone science and discuss breakthroughs in clinical care.

Tumor-induced Osteomalacia (TIO) is a rare condition in which excess FGF23 produced by a tumor leads to renal phosphate wasting, impaired 1,25(OH)2D synthesis, osteomalacia, fractures, weakness, fatigue, and decreased mobility. In an ongoing open-label Phase 2 study (NCT02304367), 17 adults with TIO or cutaneous skeletal hypophosphatemia syndrome (CSHS) were enrolled and received burosumab, a fully human monoclonal antibody against FGF23. Key endpoints were changes in serum phosphorus and osteomalacia as assessed from trans-iliac crest bone biopsies. This report excludes 3/17 subjects who did not have TIO: 2 subjects diagnosed with X-linked hypophosphatemia post-enrollment and 1 subject with CSHS. Serum phosphorus increased from baseline (BL; 1.60 mg/dL) and was maintained after titration, from Week (W) 22 (2.85 mg/dL, dosing cycle midpoint) to W144 (2.56 mg/dL, dosing cycle endpoint, p<0.0001). Serum TmP/GFR and 1,25(OH)2D also increased with burosumab. Eleven subjects underwent paired bone biopsies at BL and W48. Osteoid volume/bone volume decreased from a mean ± SE of 17.6% ± 5.9% at BL to 12.1% ± 4.7% at W48 (p=0.086). Mean ± SE osteoid thickness decreased from 16.5 ± 3.6 µm to 11.3 ± 2.8 µm (p<0.05). Using imputation (Dempster et al. 2012), mineralization lag time decreased from a mean ± SE of 1598 ± 420 days to 1032 ± 712 days (p=0.41). Osteoid surface/bone surface showed no change from BL (mean ± SE BL: 57% ± 9%, W48: 57% ± 7%). Of 249 areas identified with increased uptake on bone scan at BL, 68 (27%) and 81 (33%) were fully healed at W96 and W144, respectively; 56 (23%) and 32 (13%) were partially healed at W96 and W144, respectively. Mean (SD) Global Fatigue Score decreased from 5.6 (2.5) at BL to 3.5 (3.0) at W48, and to 3.8 (2.2) at W144 (both p<0.01). All 3 domains of the Brief Pain Inventory decreased with burosumab (W144 Pain Severity and Pain Interference p<0.05), indicating reduced pain. The SF-36 mean (SD) physical component summary score increased from 33 (10) at BL to 39 (10) at W48 (p<0.05) and to 41 (12) at W144 (p<0.01), indicating improved physical functioning. The mean (SD) number of sit-to-stand repetitions, an assessment of proximal muscle function, increased from 6.7 (4.2) at BL to 8.5 (4.2) at W48 (n=10; p<0.01). All subjects had ≥1 adverse event (AE). Two subjects discontinued: 1 to undergo chemotherapy to treat an AE of neoplasm progression and 1 failed to meet serum phosphorus dosing criteria and therefore received minimal burosumab dosing. There were 16 serious AEs in 7 subjects, all unrelated to drug. Of the 6 subjects with a serious AE of tumor progression/compression, 5 had a history of tumor progression prior to enrollment. There was 1 death, considered unrelated to treatment. In adults with TIO Syndrome, burosumab was associated with improvements in phosphate metabolism, osteomalacia, skeletal metabolism/fracture healing, physical functioning, fatigue, pain, and quality of life.

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Background: Patients with congenital adrenal hyperplasia (CAH) due to classic 21-hydroxylase deficiency have poor health outcomes related to inadequate glucocorticoid (GC) replacement. We compared disease control of adults with classic CAH treated with a modified release hydrocortisone (MRHC), which replicates physiological diurnal cortisol secretion, versus standard GC therapy.Methods: 6 month, open label, study in 122 patients randomised either to treatment with MRHC (Chronocort®, Diurnal Ltd, Cardiff, UK) twice daily at ~ 0700h & ~2300h, or to remain on their standard GC regimen (hydrocortisone, prednisolone, prednisone, dexamethasone). Patients had 24-hr profiling of serum 17-hydroxyprogesterone (17-OHP) at baseline and for dose titration at 4 and 12 weeks. The primary efficacy endpoint was the change from baseline to 24 weeks in the natural logarithm of the mean of the 24-hr standard deviation score (SDS) profile for 17-OHP.Results: Both groups achieved improved hormonal control at 24 weeks. The mean 24-hour 17-OHP SDS was significantly lower on MRHC compared to standard GC at 4 weeks (p = 0.0074) and 12 weeks (p = 0.019), but not at 24 weeks. In post-hoc analyses at 24 weeks, MRHC treatment showed a greater reduction in 17-OHP SDS compared to standard GC in the morning, 0700-1500h (p = 0.0442) and a greater reduction in log transformed 17-OHP 24 hour AUC (p=0.0251). Defining a morning 17-OHP <1200ng/dl (<36 nmol/L) as good control, for patients not controlled at baseline 85% were well controlled at 24 weeks with MHRC versus 50% on standard GC. For patients controlled at baseline 100% were controlled at 24 weeks on MHRC versus 84% with standard GC (p = 0.0018). The variability of 17-OHP over 24 hours was significantly reduced in the MRHC group compared to standard GC: the ratio of amplitude at 24 weeks divided by amplitude at baseline was for MRHC, 0.361 [95% CI: 0.235, 0.651], and standard GC, 0.917 [0.773, 1.366]; (p = 0.0001).There were no adrenal crises on MRHC and fewer stress doses despite similar incidence of inter-current illness to the standard GC group which had 3 adrenal crises. MRHC was associated with patient reported benefit including restoration of menstruation in 4 patients on MRHC and 1 on standard GC and two partner pregnancies in patients on MRHC and none on standard GC.Discussion: This is the largest randomised controlled trial of GC treatment in CAH and showed that intensification of therapy could improve control of the androgen-precursor, 17-OHP, and that this hormonal control was superior in the morning with MRHC. MRHC reduced the fluctuations in 17-OHP such that in the majority of patients the 17-OHP profile was within the reference range throughout 24 hours, providing consistent and optimal disease control.Conclusion: Diurnal cortisol replacement with a MRHC improves the biochemical control of classic CAH with a twice-daily therapeutic regimen.

A Phase 3 Study of a Modified-Release Hydrocortisone in the Treatment of Congenital Adrenal Hyperplasia

Introduction: Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21OHD CAH) is a rare autosomal recessive disease that results in impaired cortisol synthesis and excess androgen production. Compounds that inhibit adrenocorticotropic hormone (ACTH) release could reduce adrenal androgen production and thus the amounts of exogenous glucocorticoids needed to decrease these androgen levels. This study evaluated the effect of crinecerfont (NBI-74788), a novel, non-steroidal, and selective corticotropin-releasing factor-1 (CRF1) receptor antagonist on adrenal androgens and precursors in adults with 21OHD CAH.Methods: This open-label, multiple-dose study enrolled men and women (18-50 years old) with 21OHD CAH. A sequential-cohort design evaluated 4 crinecerfont oral dosing regimens: 50 mg QHS (Cohort 1); 100 mg QHS (Cohort 2); 100 mg QD (Cohort 3); and 100 mg alternative dosing (Cohort 4). Each regimen was administered for 14 consecutive days. ACTH, 17-hydroxy-progesterone (17OHP), and androstenedione (A4) were measured serially over a 24-hour period, at baseline and after 14 days of dosing.Results: Analyses included 23 participants: Cohort 1 (4 women, 4 men: mean age 31.1 years); Cohort 2 (5 women, 2 men: mean age 32.9 years); and Cohort 3 (3 women, 5 men: mean age 30.9 years). Cohort 4 is ongoing. At baseline, median plasma ACTH, serum 17OHP, and serum A4 levels were as follows: Cohort 1 (ACTH, 151 pg/mL; 17OHP, 5352 ng/dL; A4, 270 ng/dL); Cohort 2 (ACTH, 232 pg/mL; 17OHP, 12821 ng/dL; A4, 597 ng/dL); and Cohort 3 (ACTH, 470 pg/mL; 17OHP, 6451 ng/dL; A4, 299 ng/dL). After 14 days of once-daily crinecerfont 50 mg, Cohort 1 patients had median percent reductions from baseline in plasma ACTH (-54%), serum 17OHP (-60%), and serum A4 (-21%). Median percent reductions were generally larger with 100 mg in Cohort 2 (ACTH, -67%; 17OHP, -75%; A4, -47%) and Cohort 3 (ACTH, -69%; 17OHP, -55%; A4, -43%), consistent with a dose-related response. Adverse events were mostly mild; no clinically significant findings from routine laboratory tests, vital signs, or electrocardiograms were noted.Conclusions: Results of this Phase 2 study of crinecerfont, a novel, orally administered, selective CRF1-receptor antagonist, indicated clinically meaningful reductions of elevated ACTH, 17OHP, and A4 in adults with 21OHD CAH after 14 days of treatment. Further studies are warranted to evaluate the effects of chronic crinecerfont therapy on maintenance of adrenal steroid production, clinical endpoints of disordered steroidogenesis, and reductions in GC exposure in both adult and pediatric patients with 21OHD CAH.

The Effects of Crinecerfont (NBI-74788), a Novel CRF1 Receptor Antagonist, on Adrenal Androgens and Precursors in Patients with Classic Congenital Adrenal Hyperplasia: Results from A Multiple-Dose Phase 2 Study

Background: The management of youth presenting with delayed puberty is challenging because it can be difficult to predict which children will eventually progress through puberty and which children will not. We have previously shown that exogenous administration of the neuropeptide kisspeptin, which stimulates GnRH release, can be used to probe the integrity of the reproductive endocrine axis. We hypothesized that responses to kisspeptin could predict outcomes for individuals with pubertal delay. Methods: We conducted a longitudinal study of 16 children (3 girls and 13 boys) with delayed or stalled puberty who had undergone stimulation testing with kisspeptin and GnRH. Participants were followed with serial physical examinations and laboratory studies every six months for evidence of progression through puberty. Inhibin B was measured in boys. A subset of participants underwent exome sequencing. Results: “Kisspeptin responders” who had responded to kisspeptin with a rise in LH of 0.8 mIU/mL or greater all subsequently progressed through puberty (n = 8). In contrast, “kisspeptin nonresponders” who had exhibited LH responses to kisspeptin ≤0.4 mIU/mL all reached age 18 years without developing physical signs of puberty (n = 8). Thus, responses to kisspeptin accurately predicted later pubertal outcomes (p = 0.0002), with sensitivity and specificity of 100% (95% CI 74-100%). Moreover, the kisspeptin-stimulation test outperformed overnight LH measurements, GnRH-stimulated LH, inhibin B, and genetic testing in predicting pubertal outcomes. Conclusion: The kisspeptin-stimulation test can be used to reveal future reproductive endocrine potential in prepubertal children and is a promising novel tool for predicting pubertal outcomes for children with delayed puberty. Trial registration: ClinicalTrials.gov NCT01438034

Using Kisspeptin to Predict Pubertal Outcomes for Youth With Pubertal Delay

De novo lipogenesis (DNL) plays a role in the development of hepatic steatosis and non-alcoholic fatty liver disease (NAFLD). In rodent models of both health and lipodystrophy (LD), leptin decreases DNL. In human patients with LD, reduced adipose tissue results in adipokine deficiencies, including lower plasma leptin, which contributes to insulin resistance, dyslipidemia and ectopic accumulation of triglycerides (TG). The mechanisms by which leptin regulates serum and hepatic-TG are not well elucidated. Studying patients with LD before and after leptin therapy provides an important clinical model for understanding leptin’s effect on DNL. We hypothesized that leptin treatment in lipodystrophic patients would decrease DNL by decreasing insulin resistance and glycemia, resulting in reduced circulating and hepatic-TG.Leptin-naïve patients with LD (n=11) were treated with recombinant leptin (metreleptin) for 6 months. All measurements were performed after an 8-12 hr fast. The % of TG in TG-rich lipoproteins (TRLP-TG) derived from DNL (% DNL) was measured using body water labeling (oral D2O) of TG and mass spectrometry analysis. Absolute DNL was calculated as the product of TRLP-TG and % DNL. HbA1c and serum-TG were measured biochemically, hepatic-TG by MRI, and total body and hepatic insulin sensitivity measured during a hyperinsulinemic-euglycemic clamp.DNL decreased after metreleptin: % DNL from 22.8±6.8 to 9.1±5.1% (p=0.0008) and absolute DNL from 54.2±32.1 to 8.6±6.5 mg/dl (p=0.003). TRLP-TG decreased from (median [interquartile range]) 160 [107, 280] to 98 [66, 147] mg/dl (p=0.01). Total body and hepatic insulin sensitivity increased from 3.7 [3.0, 7.3] to 8.4 [5.1,10.6] mg/kgFFM/min (p=0.03) and from 61.0 [48.5, 69.3] to 84.7 [75.2, 107.6] % (p =0.01), respectively. HbA1c decreased from 8.6±1.8 to 7.1±1.4% (p=0.04), hepatic-TG decreased from 17.6±11.9 to 10.3±9.1% (p=0.02), and serum-TG from 386 [216, 686] to 223 [118, 497] mg/dl (p=0.06). DNL correlated negatively with insulin sensitivity both before (r=-0.73, p=0.03) and after (r=-0.85, p=0.004) metreleptin. DNL correlated positively with hepatic-TG before (r=0.70 p=0.03) and tended to correlate after metreleptin (r=0.65, p=0.06). The change in DNL correlated with change in serum-TG (r=0.77, p=0.04) but not the change in hepatic-TG (p=0.80).We show here for the first time that 6 months of metreleptin treatment in humans with LD decreased DNL by 84% and was associated with reductions in glycemia and improved peripheral and hepatic insulin sensitivity. These data indicate a strong link between metreleptin’s effects to increase clearance of blood glucose by peripheral tissues and reduce hepatic carbohydrate flux, resulting in DNL reductions. This led to lowered hepatic steatosis and dyslipidemia and suggests treatments that target multi-organ insulin resistance may lead to decreased NAFLD and cardiovascular risk.

Leptin Decreases De Novo Lipogenesis in Lipodystrophic Patients

Objective: There is limited data regarding the use of diabetes technology such as continuous glucose monitor (CGM) and continuous subcutaneous insulin infusion (CSII) among patients with type 1 diabetes (T1D) in a minority serving and safety-net hospital. We examined racial differences in the use of CGM and CSII in this setting.Methods: A retrospective review of 227 patients ≥ 18 years of age with T1D seen in the Endocrinology clinic at a safety-net hospital from October 2016 and September 2017 was completed. Statistical analysis assessed the likelihood of diabetes technology use among different races.Results: The mean age was 39, 59% male, mean duration of diabetes was 21 years, 30% overweight, 22% obesity, 80% English speaking, and 50% had government insurance. In terms of the distribution of race/ethnicity, 43% were Caucasian, 25% African American (AA), 15% Hispanic, 15% defined as other, and 2% Asian. Mean HbA1c ± standard deviation (SD) of any technology (either CGM or CSII or both) and non-technology users were 8.27 ± 1.58 and 9.49 ± 2.04, respectively. Patients who had government health insurance were found to have lower odds of using technology (odds ratio [OR], 0.43; 95% confidential interval [CI], 0.25 - 0.74) compared to patients who had private health insurance. Overall, 26% of the patients used CSII with 43% of this population Caucasian, 10.5% AA and 14.2% Hispanic. The overall CGM use was 30% with 47% of users Caucasian, 14% AA and 22% Hispanic. In a multivariable logistic regression model that adjusted for insurance and language, AA or other were found to have statistically significant lower odds of using technology (AA OR 0.25 [95% CI 0.11 - 0.53] and other OR 0.33 [95% CI 0.12 - 0.89]) compared to the Caucasian group.Conclusion: Our study showed that the use of technology in the Caucasian group was statistically significantly higher than in the non-Caucasian groups except for the Asian group. After adjusting for insurance and language, AA and other demonstrated statistically lower rates of technology use. Racial differences in diabetes technology use were observed in our study as well as the association between technology use and lowered HbA1c. Given diabetes technology is a useful tool in reducing HbA1c and hypoglycemia, the barriers to accessing diabetes technology in non-Caucasian individuals should be addressed to decrease health disparities.

Racial Differences in Technology Use Among Type 1 Diabetes in a Safety-Net Hospital

Background: Pediatric obesity is a chronic disease with rising prevalence and limited treatment options; first-line intervention is lifestyle therapy, which is typically unsuccessful.1 Liraglutide (3.0 mg) as an adjunct to lifestyle therapy has provided weight loss and improved cardiometabolic risk factors in adults.2 Here we report the results of liraglutide 3.0 mg in adolescents with obesity who failed to respond to lifestyle therapy.Methods: A multinational, randomized, double-blind trial (NCT02918279) with a 12-wk run-in of lifestyle therapy, 4-8-wk dose escalation, 52-wk maintenance period and 26-wk follow-up off trial drug. Adolescents aged 12-<18 years with obesity, stable weight and suboptimal response to lifestyle therapy alone were randomized 1:1 to once-daily subcutaneous liraglutide 3.0 mg (or maximum tolerated dose) or placebo (PBO), both as an adjunct to lifestyle therapy. Randomization was stratified by pubertal and glycemic (normal vs prediabetes/type 2 diabetes) status. Primary endpoint was change in BMI standard deviation score (SDS)3 from wk 0 to 56.Results: Of 125 adolescents randomized to liraglutide 3.0 mg and 126 to PBO, 101 and 100 completed treatment at wk 56, respectively; 99 in each arm completed the trial at wk 82. 40.6% were male; mean age 14.5 years; mean BMI 35.6 kg/m2; mean BMI SDS 3.17. Liraglutide 3.0 mg was superior to PBO for change in BMI SDS at wk 56 (estimated treatment difference [ETD] -0.22; 95% CI -0.37, -0.08; p=0.0022). In the liraglutide 3.0 mg vs PBO arm, 43.25% vs 18.73% (p=0.0002) and 26.08% vs 8.11% (p=0.0006) of adolescents had ≥5% and ≥10% reduction in baseline BMI at wk 56, respectively. A significant difference in change in BMI was seen for liraglutide 3.0 mg vs PBO: ETD -4.64%; 95% CI -7.14, -2.14; p=0.0003. A significant reduction in waist circumference with liraglutide 3.0 mg was shown at wk 56 (p=0.0126). Greater weight regain/rebound in BMI SDS at wk 82 was seen for liraglutide 3.0 mg vs PBO after drug discontinuation (ETD 0.15; 95% CI 0.07, 0.23; p=0.0002). There were no significant differences in blood pressure, fasting lipids, fasting plasma glucose or HbA1c at wk 56. No unexpected safety concerns and no severe hypoglycemia were reported. During treatment (0-56 wks), more adolescents in the liraglutide 3.0 mg (64.8%) vs PBO arm (36.5%) reported gastrointestinal adverse events (AEs), and 3 vs 5 adolescents, respectively, reported serious AEs. Mental health questionnaire results were similar in both arms at wk 56. No effect on growth or pubertal development was found.Conclusions: This trial demonstrates clinically meaningful4 weight loss in adolescents with obesity treated with liraglutide 3.0 mg as an adjunct to lifestyle therapy. The safety profile was similar to that observed in adults.References1. Ryder et al Obesity 2018;26:9512. Pi-Sunyer et al N Engl J Med 2015;373:113. EMA doc. ref. EMEA/402888/20084. Grossman et al JAMA 2017;317:2417

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Burosumab Improves Biochemical, Skeletal, and Clinical Features of Tumor-Induced Osteomalacia Syndrome

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