Rationale for Use of Sphingosine-1-Phosphate Receptor Modulators in COVID-19 Patients: Overview of Scientific Evidence.

Maladjusted immune responses to the coronavirus disease 2019 (COVID-19), for example, cytokine release syndrome, may result in immunopathology and acute respiratory distress syndrome. Sphingosine-1-phosphate (S1P), a bioactive lipid mediator, and its S1P receptor (S1PR) are crucial in maintaining endothelial cell chemotaxis and barrier integrity. Apart from the S1P1 receptor-mediated mechanisms of sequestration of cytotoxic lymphocytes, including Th-17 and S1P1/2/3-mediated endothelial barrier functions, S1PR modulators may also attenuate cytokine release via activation of serine/threonine protein phosphatase 2A and enhance the pulmonary endothelial barrier via the c-Abl tyrosine kinase pathway. Chronic treatment with fingolimod (S1PR1,3,4,5 modulator) and siponimod (S1PR1,5 modulator) has demonstrated efficacy in reducing inflammatory disease activity and slowing down disease progression in multiple sclerosis. The decision to selectively suppress the immunity of a critically ill patient with COVID-19 remains a difficult choice. It has been suggested that treatment with fingolimod or siponimod may be appropriate to attenuate severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-induced hyperinflammation in patients with COVID-19 since these patients are already monitored in an intensive care setting. Here, we review the use of S1PR modulators, fingolimod and siponimod, in regulating the inflammatory response to SARS-CoV-2 with the aim of understanding their potential rationale use in patients with COVID-19.

Pharmacokinetics and Pharmacodynamics of Bimagrumab (BYM338).

BACKGROUND: Bimagrumab is a human monoclonal antibody binding to the activin type II receptor with therapeutic potential in conditions of muscle wasting and obesity. This phase I study evaluated the pharmacokinetics (PK), pharmacodynamics (PD), and safety of various dose regimens of bimagrumab and routes of administration in healthy older adults. METHODS: This was a randomized, double-blind, placebo-controlled, parallel-arm, multiple-dose study in older adult men and women (aged ≥ 70 years, body mass index [BMI] 18-34 kg/m2) with stable health and diet. The study comprised seven treatment groups (Cohorts 1-7). Participants received bimagrumab or placebo treatment every 4 weeks for three doses (Cohorts 1 [700 mg] and 2 [210 mg] intravenous infusion; Cohorts 3 [1500 mg] and 4 [525 mg] subcutaneous infusion), or every week for 12 doses (Cohorts 5 [300 mg], 6 [150 mg], and 7 [52.5 mg] subcutaneous bolus injection) and were followed up until week 20. Blood samples were collected for bimagrumab PK analysis. PD were assessed by dual energy X-ray absorptiometry to quantify the change from baseline in lean body mass (LBM) and fat body mass (FBM) compared with placebo. Safety was assessed throughout the study. RESULTS: Eighty-four of 91 (92.3%) randomized participants (mean age 74.5 years; BMI 28.0 kg/m2) completed the study. Demographic characteristics were generally balanced across the groups. A target-mediated drug disposition profile was observed following both intravenous and subcutaneous administration. The absolute subcutaneous bioavailability was estimated at approximately 40%. LBM increased by 4-6% (1.5-2 kg) from baseline throughout the treatment period for intravenous and subcutaneous regimens, except for the 52.5 mg subcutaneous dose, which did not differ from placebo. Concurrently, there was a decrease in FBM (approximately 2-3 kg) for all intravenous and subcutaneous regimens. Bimagrumab was generally safe and well tolerated; adverse events were mostly mild to moderate in severity. CONCLUSIONS: Dose levels of bimagrumab administered weekly subcutaneously resulted in PK profiles and PD effects comparable with monthly intravenous dosing, which supports the feasibility of the subcutaneous route of administration for bimagrumab for future clinical development.

Effect of Bimagrumab vs Placebo on Body Fat Mass Among Adults With Type 2 Diabetes and Obesity: A Phase 2 Randomized Clinical Trial.

Importance: Antibody blockade of activin type II receptor (ActRII) signaling stimulates skeletal muscle growth. Previous clinical studies suggest that ActRII inhibition with the monoclonal antibody bimagrumab also promotes excess adipose tissue loss and improves insulin resistance. Objective: To evaluate the efficacy and safety of bimagrumab on body composition and glycemic control in adults with type 2 diabetes and overweight and obesity. Design, Setting, and Participants: This double-masked, placebo-controlled, 48-week, phase 2 randomized clinical trial was conducted among adults with type 2 diabetes, body mass index between 28 and 40, and glycated hemoglobin (HbA1c) levels between 6.5% and 10.0% at 9 US and UK sites. The trial was conducted from February 2017 to May 2019. Only participants who completed a full treatment regimen were included in analysis. Interventions: Patients were randomized to intravenous infusion of bimagrumab (10 mg/kg up to 1200 mg in 5% dextrose solution) or placebo (5% dextrose solution) treatment every 4 weeks for 48 weeks; both groups received diet and exercise counseling. Main Outcomes and Measures: The primary end point was least square mean change from baseline to week 48 in total body fat mass (FM); secondary and exploratory end points were lean mass (LM), waist circumference (WC), HbA1c level, and body weight (BW) changes from baseline to week 48. Results: A total of 75 patients were randomized to bimagrumab (n = 37; 23 [62.2%] women) or placebo (n = 38; 12 [31.6%] women); 58 (77.3%) completed the 48-week study. Patients at baseline had a mean (SD) age of 60.4 (7.7) years; mean (SD) BMI of 32.9 (3.4); mean (SD) BW of 93.6 (14.9) kg; mean (SD) FM of 35.4 (7.5) kg; and mean (SD) HbA1c level of 7.8% (1.0%). Changes at week 48 for bimagrumab vs placebo were as follows: FM, -20.5% (-7.5 kg [80% CI, -8.3 to -6.6 kg]) vs -0.5% (-0.18 kg [80% CI, -0.99 to 0.63 kg]) (P < .001); LM, 3.6% (1.70 kg [80% CI, 1.1 to 2.3 kg]) vs -0.8% (-0.4 kg [80% CI, -1.0 to 0.1 kg]) (P < .001); WC, -9.0 cm (80% CI, -10.3 to -7.7 cm) vs 0.5 cm (80% CI, -0.8 to 1.7 cm) (P < .001); HbA1c level, -0.76 percentage points (80% CI, -1.05 to -0.48 percentage points) vs -0.04 percentage points (80% CI, -0.23 to 0.31 percentage points) (P = .005); and BW, -6.5% (-5.9 kg [80% CI, -7.1 to -4.7 kg]) vs -0.8% (-0.8 kg [80% CI, -1.9 to 0.3 kg]) (P < .001). Bimagrumab's safety and tolerability profile was consistent with prior studies. Conclusions and Relevance: In this phase 2 randomized clinical trial, ActRII blockade with bimagrumab led to significant loss of FM, gain in LM, and metabolic improvements during 48 weeks in patients with overweight or obesity who had type 2 diabetes. ActRII pathway inhibition may provide a novel approach for the pharmacologic management of excess adiposity and accompanying metabolic disturbances. Trial Registration: ClinicalTrials.gov number: NCT03005288.

Safety and pharmacokinetics of bimagrumab in healthy older and obese adults with body composition changes in the older cohort.

BACKGROUND: Bimagrumab prevents activity of myostatin and other negative regulators of skeletal muscle mass. This randomized double-blind, placebo-controlled study investigated safety, pharmacokinetics (PK), and pharmacodynamics of bimagrumab in healthy older and obese adults. METHODS: A cohort of older adults (aged 70-85 years) received single intravenous infusions of bimagrumab 30 mg/kg (n = 6) or 3 mg/kg (n = 6) or placebo (n = 4) and was followed for 20 weeks. A second cohort of obese participants [body mass index (BMI) 30-45 kg/m2 , aged 18-65 years] received a single intravenous infusion of bimagrumab 30 mg/kg (n = 6) or placebo (n = 2) and was followed for 12 weeks. Outcomes included the safety, tolerability, and PK of bimagrumab, in both cohorts. Measures of pharmacodynamics were performed in the older adult cohort to evaluate the effects of bimagrumab on thigh muscle volume (TMV), total lean body mass (LBM), total fat body mass, and muscle strength. RESULTS: All 24 randomized participants completed the study. The older adults had a mean (±SD) age of 74.5 ± 3.4 years and BMI of 26.5 ± 3.5 kg/m2 . The obese participants had a mean (±SD) age of 40.4 ± 11.8 years, weight of 98.0 ± 11.3 kg, and BMI of 34.3 ± 3.9 kg/m2 . Adverse events in both cohorts were mostly mild. In older adults, most commonly reported adverse events were upper respiratory tract infection, rash, and diarrhoea (each 3/16, 19%). Obese participants reported muscle spasms and rash (both 5/8, 63%) most often. Non-linearity was observed in the PK concentration profiles of both cohorts due to target-mediated drug disposition. Bimagrumab 3 and 30 mg/kg increased mean (±SD) TMV (Week 4: 5.3 ± 1.8% and 6.1 ± 2.2%, vs. placebo: 0.5 ± 2.1%, both P ≤ 0.02) and LBM (Week 4: 6.0 ± 3.2%, P = 0.03 and 2.4 ± 2.2%, vs. placebo: 0.1 ± 2.4%), which were maintained longer with higher dose level, while total fat body mass (Week 4: -2.7 ± 2.9% and -1.6 ± 3.0%, vs. placebo: -2.3 ± 3.2%) decreased from baseline in older adults, with no change in muscle strength. CONCLUSIONS: Bimagrumab was safe and well tolerated and demonstrated similar PK in older and obese adults. A single dose of bimagrumab rapidly increased TMV and LBM and decreased body adiposity in older adults. Muscle hypertrophy and fat loss were sustained with extended drug exposure.

Bimagrumab vs Optimized Standard of Care for Treatment of Sarcopenia in Community-Dwelling Older Adults: A Randomized Clinical Trial.

Importance: The potential benefit of novel skeletal muscle anabolic agents to improve physical function in people with sarcopenia and other muscle wasting diseases is unknown. Objective: To confirm the safety and efficacy of bimagrumab plus the new standard of care on skeletal muscle mass, strength, and physical function compared with standard of care alone in community-dwelling older adults with sarcopenia. Design, Setting, and Participants: This double-blind, placebo-controlled, randomized clinical trial was conducted at 38 sites in 13 countries among community-dwelling men and women aged 70 years and older meeting gait speed and skeletal muscle criteria for sarcopenia. The study was conducted from December 2014 to June 2018, and analyses were conducted from August to November 2018. Interventions: Bimagrumab 700 mg or placebo monthly for 6 months with adequate diet and home-based exercise. Main Outcomes and Measures: The primary outcome was the change in Short Physical Performance Battery (SPPB) score after 24 weeks of treatment. Secondary outcomes included 6-minute walk distance, usual gait speed, handgrip strength, lean body mass, fat body mass, and standard safety parameters. Results: A total of 180 participants were recruited, with 113 randomized to bimagrumab and 67 randomized to placebo. Among these, 159 participants (88.3%; mean [SD] age, 79.1 [5.3] years; 109 [60.6%] women) completed the study. The mean SPPB score increased by a mean of 1.34 (95% CI, 0.90 to 1.77) with bimagrumab vs 1.03 (95% CI, 0.53 to 1.52) with placebo (P = .13); 6-minute walk distance increased by a mean of 24.60 (95% CI, 7.65 to 41.56) m with bimagrumab vs 14.30 (95% CI, -4.64 to 33.23) m with placebo (P = .16); and gait speed increased by a mean of 0.14 (95% CI, 0.09 to 0.18) m/s with bimagrumab vs 0.11 (95% CI, 0.05 to 0.16) m/s with placebo (P = .16). Bimagrumab was safe and well-tolerated and increased lean body mass by 7% (95% CI, 6% to 8%) vs 1% (95% CI, 0% to 2%) with placebo, resulting in difference of 6% (95% CI, 4% to 7%) (P < .001). Conclusions and Relevance: This randomized clinical trial found no significant difference between participants treated with bimagrumab vs placebo among older adults with sarcopenia who had 6 months of adequate nutrition and light exercise, with physical function improving in both groups. Bimagrumab treatment was safe, well-tolerated, increased lean body mass, and decreased fat body mass. The effects of sarcopenia, an increasing cause of disability in older adults, can be reduced with proper diet and exercise. Trial Registration: ClinicalTrials.gov Identifier: NCT02333331; EudraCT number: 2014-003482-25.

Treatment of primary Sjögren's syndrome with ianalumab (VAY736) targeting B cells by BAFF receptor blockade coupled with enhanced, antibody-dependent cellular cytotoxicity.

OBJECTIVES: To evaluate the efficacy and safety of ianalumab (VAY736), a B cell-depleting, B cell activating factor receptor-blocking, monoclonal antibody, in patients with active primary Sjögren's syndrome (pSS) in a double-blind, placebo-controlled, phase II, single-centre study. METHODS: Patients with pSS, EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) ≥6, were randomised to ianalumab single infusion at either 3 mg/kg (n=6), 10 mg/kg (n=12) or placebo (n=9). Outcomes were measured blinded at baseline and weeks 6, 12, 24, and unblinded at end of study (EoS) when B cell numbers had recovered. Clinical outcomes included ESSDAI, EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI), salivary flow rate, ocular staining score, physician global assessment and patient assessments of fatigue and general quality of life. Laboratory-based measures included circulating leucocyte subsets and markers of B cell activity. RESULTS: A similar trend showing positive therapeutic effect by ianalumab was observed across the primary clinical outcome (ESSDAI) and all secondary clinical outcomes (ESSPRI, Multidimensional Fatigue Inventory, Short Form-36, global assessments by physician and patient) versus the placebo-treated group. Rapid and profound B cell depletion of long-lasting duration occurred after a single infusion of ianalumab at either dose. Serum Ig light chains decreased, with return to baseline levels at EoS. Changes in some clinical outcomes persisted through to EoS in the higher dose group. Adverse effects were largely limited to mild to moderate infusion reactions within 24 hours of ianalumab administration. CONCLUSIONS: Overall results in this single-dose study suggest potent and sustained B cell depletion by ianalumab could provide therapeutic benefits in patients with pSS without major side effects.

Safety, tolerability, and preliminary efficacy of an IGF-1 mimetic in patients with spinal and bulbar muscular atrophy: a randomised, placebo-controlled trial.

BACKGROUND: Spinal and bulbar muscular atrophy is an X-linked neuromuscular disease caused by CAG repeat expansion in the androgen receptor gene. Patients with this disease have low concentrations of insulin-like growth factor-1 (IGF-1), and studies of overexpression and administration of IGF-1 showed benefit in a transgenic model; thus the IGF-1 pathway presents as a potential treatment target. We assessed safety, tolerability, and preliminary efficacy of BVS857, an IGF-1 mimetic, in patients with spinal and bulbar muscular atrophy. METHODS: In this randomised, double-blind, placebo-controlled trial, we recruited patients from neuromuscular centres in Denmark (Copenhagen), Germany (Ulm), Italy (Padova), and three sites within the USA (Bethesda, MD; Irvine, CA; and Columbus, OH). Eligible patients were 18 years or older with a confirmed genetic diagnosis of spinal and bulbar muscular atrophy, were ambulatory, had symptomatic weakness, and had serum IGF-1 concentrations of 170 ng/mL or lower. Patients were randomly assigned (2:1) to study drug or placebo by a number scheme. Patients, investigators, and study personnel were masked to treatment assignment. After a safety and tolerability assessment with eight patients, BVS857 was administered once a week (0·06 mg/kg intravenously) for 12 weeks. Primary outcome measures were safety, tolerability, and the effects of BVS857 on thigh muscle volume (TMV) measured by MRI. The ratio of TMV at day 85 to baseline was analysed with ANCOVA per protocol. Secondary outcomes of muscle strength and function were measured with the Adult Myopathy Assessment Tool, lean body mass through dual energy x-ray absorptiometry, and BVS857 pharmacokinetics. This trial was registered with ClinicalTrials.gov, NCT02024932. FINDINGS: 31 patients were assessed for eligibility, 27 of whom were randomly assigned to either BVS857 treatment (n=18) or placebo (n=9), and 24 were included in the preliminary efficacy analysis (BVS857 group, n=15; placebo group, n=9). BVS857 was generally safe with no serious adverse events. No significant differences were found in adverse events between the BVS857 and placebo groups. Immunogenicity was detected in 13 (72%) of 18 patients in the BVS857 group, including crossreacting antibodies with neutralising capacity to endogenous IGF-1 in five patients. TMV decreased from baseline to day 85 in the placebo group (-3·4% [-110 cm3]) but not in the BVS857 group (0% [2 cm3]). A significant difference in change in TMV was observed in the BVS857 group versus the placebo group (geometric-mean ratio 1·04 [90% CI 1·01-1·07]; p=0·02). There were no differences between groups in measures of muscle strength and function. INTERPRETATION: TMV remained stable in patients with spinal and bulbar muscular atrophy after being given BVS857 for 12 weeks. The intervention was associated with high incidence of immunogenicity and did not improve muscle strength or function. Additional studies might be needed to assess the efficacy of activating the IGF-1 pathway in this disease. FUNDING: Novartis Pharmaceuticals and the US National Institutes of Health.

Effects of bimagrumab, an activin receptor type II inhibitor, on pituitary neurohormonal axes.

BACKGROUND: Bimagrumab is a human monoclonal antibody inhibitor of activin type II receptors (ActRII), with anabolic action on skeletal muscle mass by blocking binding of myostatin and other negative regulators of muscle growth. Bimagrumab is under evaluation for muscle wasting and associated functional loss in hip fracture and sarcopenia, and in obesity. Bimagrumab also blocks other endogenous ActRII ligands, such as activins, which act on the neurohormonal axes, pituitary, gonads and adrenal glands. AIM: To evaluate the effect of bimagrumab on the pituitary-gonadal and pituitary-adrenal axes in humans. METHODS: Healthy men and women, aged 55 to 75 years, received bimagrumab intravenously 10 mg/kg or placebo on Day 1 and Day 29. Pituitary-gonadal and pituitary-adrenal functions were evaluated with basal hormone measurement and standard gonadotropin-releasing hormone (GnRH) and adrenocorticotropic hormone (ACTH) stimulation tests at baseline, Week 8 and at the end of study (EOS)-Week 20. RESULTS: At Week 8, follicle-stimulating hormone (FSH) levels were reduced by 42.16 IU/L (P < .001) and luteinizing hormone (LH) levels were increased by 2.5 IU/L (P = .08) over placebo in response to bimagrumab in women but not in men. Effects that were reversible after bimagrumab was cleared. Gonadal and adrenal androgen levels were not affected by exposure to bimagrumab. CONCLUSION: Bimagrumab alters the function of pituitary gonadotroph cells, consistent with blockade of activin on local ActRII. This effect is reversible with clearance of bimagrumab. Bimagrumab did not impact gonadal and adrenal androgen secretion.

Bimagrumab improves body composition and insulin sensitivity in insulin-resistant individuals.

AIM: To test the hypothesis that an improving body composition in insulin-resistant individuals could enhance insulin sensitivity. METHODS: A total of 16 people with a mean body mass index of 29.3 kg/m2 and insulin resistance, received a single dose of bimagrumab or placebo and were assessed at week 10 for insulin sensitivity, using a hyperinsulinaemic-euglycaemic clamp and an intravenous glucose tolerance test (IVGTT), and for body composition using dual energy X-ray absorptiometry and positron-emission tomography. RESULTS: Bimagrumab increased lean mass by 2.7% (P < .05) and reduced fat mass by 7.9% (P = .011) at week 10 compared with placebo, and had a neutral effect on body weight. Bimagrumab reduced glycated haemoglobin by 0.21% at week 18 (P < .001) and improved insulin sensitivity by ~20% (according to the clamp) to ~40% (according to the IVGTT). CONCLUSION: Taking the observed changes together, and given that these occurred without accompanying dietary intervention and without any prescribed regular physical exercise, bimagrumab may offer a novel approach for the treatment of the metabolic complications of obesity.

Treatment of Sarcopenia with Bimagrumab: Results from a Phase II, Randomized, Controlled, Proof-of-Concept Study.

OBJECTIVES: To assess the effects of bimagrumab on skeletal muscle mass and function in older adults with sarcopenia and mobility limitations. DESIGN: A 24-week, randomized, double-blind, placebo-controlled, parallel-arm, proof-of-concept study. SETTING: Five centers in the United States. PARTICIPANTS: Community-dwelling adults (N = 40) aged 65 and older with gait speed between 0.4 and 1.0 m/s over 4 m and an appendicular skeletal muscle index of 7.25 kg/m2 or less for men and 5.67 kg/m2 or less for women. INTERVENTION: Intravenous bimagrumab 30 mg/kg (n = 19) or placebo (n = 21). MEASUREMENTS: Change from baseline in thigh muscle volume (TMV), subcutaneous and intermuscular fat, appendicular and total lean body mass, grip strength, gait speed, and 6-minute walk distance (6MWD). RESULTS: Thirty-two (80%) participants completed the study. TMV increased by Week 2, was sustained throughout the treatment period, and remained above baseline at the end of study in bimagrumab-treated participants, whereas there was no change with placebo treatment (Week 2: 5.15 ± 2.19% vs -0.34 ± 2.59%, P < .001; Week 4: 6.12 ± 2.56% vs 0.16 ± 3.42%, P < .001; Week 8: 8.01 ± 3.70% vs 0.35 ± 3.32%, P < .001; Week 16: 7.72 ± 5.31% vs 0.42 ± 5.14%, P < .001; Week 24: 4.80 ± 5.81% vs -1.01 ± 4.43%, P = .002). Participants with slower walking speed at baseline receiving bimagrumab had clinically meaningful and statistically significantly greater improvements in gait speed (mean 0.15 m/s, P = .009) and 6MWD (mean 82 m, P = .022) than those receiving placebo at Week 16. Adverse events in the bimagrumab group included muscle-related symptoms, acne, and diarrhea, most of which were mild in severity and resolved by the end of study. CONCLUSION: Treatment with bimagrumab over 16 weeks increased muscle mass and strength in older adults with sarcopenia and improved mobility in those with slow walking speed.

Clinical pharmacokinetics of intranasal sumatriptan.

A substantial proportion of migraine patients have gastric stasis and suffer severe nausea and/or vomiting during their migraine attack. This may lead to erratic absorption from the gastrointestinal tract and make oral treatment unsatisfactory. For such patients, an intranasal formulation may be advantageous. Sumatriptan is a potent serotonin 5HT(1B/1D) agonist widely used in the treatment of migraine; the effectiveness of the intranasal formulation (20mg) has been well established in several clinical studies. This article reviews the pharmacokinetics of intranasal sumatriptan and includes comparisons with oral and subcutaneous administration. After intranasal administration, sumatriptan is directly and rapidly absorbed, with 60% of the maximum plasma concentration (C(max)) occurring at 30 minutes after administration of a single 20mg dose. Following intranasal administration, approximately 10% more sumatriptan is absorbed probably via the nasal mucosa when compared with oral administration. Mean C(max) after a 20mg intranasal dose is approximately 13.1 to 14.4 ng/mL, with median time to C(max) approximately 1 to 1.75 hours. When given as a single dose, intranasal sumatriptan displays dose proportionality in its extent of absorption and C(max) over the dose range 5 to 10mg, but not between 5 and 20mg for C(max). The elimination phase half-life is approximately 2 hours, consistent with administration by other routes. Sumatriptan is metabolised by monoamine oxidase (MAO; predominantly the A isozyme, MAO-A) to an inactive metabolite. Coadministration with a MAO-A inhibitor, moclobemide, leads to a significant increase in sumatriptan plasma concentrations and is contraindicated. Single-dose pharmacokinetics in paediatric and adolescent patients following intranasal sumatriptan were studied to determine the effect of changes in nasal morphology during growth, and of body size, on pharmacokinetic parameters. The pharmacokinetic profile observed in adults was maintained in the adolescent population; generally, factors such as age, bodyweight or height did not significantly affect the pharmacokinetics. In children below 12 years, C(max) is comparable to that seen in adolescents and adults, but total exposure (area under the concentration-time curve from zero to infinity) was lower in children compared with older patients, especially in younger children treated with 5mg. Clinical experience suggests that intranasal sumatriptan has some advantages over the tablet (more rapid onset of effect and use in patients with gastrointestinal complaints) or subcutaneous (noninvasive and fewer adverse events) formulations.