Effects of Subcutaneous Pasireotide on Cardiac Repolarization in Healthy Volunteers: a Single‐Center, Phase I, Randomized, Four‐Way Crossover Study

An Overview of Cardiovascular Risk in Pituitary Disorders

Cardiovascular comorbidities owing to hormonal excess or deficiency are the main cause of mortality in patients with pituitary disorders. In patients with Cushing's Disease, there is an increased prevalence of cardiovascular diseases and/or risk factors including visceral obesity, insulin resistance, atherosclerosis, arterial hypertension, dyslipidaemia, hypercoagulability as well as structural and functional changes in the heart, like cardiac hypertrophy and left ventricle (LV) dysfunction. Notably, these demonstrate limited reversibility even after remission. Furthermore, patients with acromegaly may manifest insulin resistance but also structural and functional heart changes, also known as "acromegalic cardiomyopathy". Patients with prolactinomas demonstrate an aggravation of metabolic parameters, obesity, dysregulation of glucose and lipid metabolism as well as endothelial dysfunction. Hypopituitarism and conventional hormonal replacement therapy may also contribute to an unhealthy metabolic status, which promotes atherosclerosis and may lead to premature mortality. This review discusses the literature on cardiovascular risk in patients with pituitary disorders to increase physician awareness regarding this aspect of management in patients with pituitary disorders.

Efficacy and Safety of Pegvisomant in the Treatment of Acromegaly

Pegvisomant, the first and currently only clinically available growth hormone receptor antagonist, is an effective therapeutic option for the medical treatment of acromegaly, a rare disorder characterized by excessive growth hormone secretion. With now over 20 years of real world experience, its safety and efficacy is well-established. However, several aspects of its clinical use are still controversially discussed. The high cost of pegvisomant has limited its use in several countries, and recent studies have reported a lower efficacy than the initial clinical trials. A reported increase in tumor volume under therapy varies between studies and has been attributed to either actual growth or re-expansion after cessation of somatostatin receptor ligand therapy. Furthermore, different combinations of pegvisomant and other therapeutic agents aiming at reduction of acromegaly disease activity have been proposed to increase or retain effectiveness while lowering side effects and cost. This review aims to assess current clinical data on the safety and efficacy of pegvisomant while also addressing controversies surrounding its use.

Long-term Efficacy and Safety of Pasireotide in Patients With Acromegaly: 14 Years of Single-Center Real-World Experience

CONTEXT

Acromegaly is a rare, chronic, debilitating disorder caused by prolonged hypersecretion of growth hormone (GH) and overproduction of insulin-like growth factor I (IGF-I). Medical therapies, including the somatostatin receptor ligand (SRL) pasireotide, are frequently used to restore biochemical control.

OBJECTIVE

As patients often receive therapy over prolonged periods, long-term data from real-life settings are needed.

METHODS

A retrospective analysis was performed using a prospectively maintained database of all patients with acromegaly from our primary care center who were enrolled in clinical studies with pasireotide (first visit November 2008). The main outcome measures were safety and biochemical control (age-adjusted IGF-I ≤ upper limit of normal).

RESULTS

Patients (n = 50) entered 4 parental studies and 30 continued in the rollover; at data cutoff (June 2022), 27 were still receiving pasireotide. Overall, median (range) exposure was 58 (3-137) months. Normal IGF-I was achieved in 54%, and acromegaly symptoms and quality of life were improved with treatment. No predictors of pasireotide response were identified; however, controlled patients had smaller tumors and lower GH at baseline. Tumor volume reduction occurred in 63% of evaluable patients (n = 10/16). Most patients presented hyperglycemic events, including 63.2% of patients with normal glucose before treatment. Older patients and those with higher IGF-I, glucose, and HbA1c at baseline had higher glucose and HbA1c during pasireotide treatment.

CONCLUSION

Pasireotide provided clinical benefit and was well tolerated for more than 11 years of treatment in acromegaly patients, most of whom were resistant to first-generation SRLs.

Pharmacokinetics and Safety of Long-Acting Release Formulations of Pasireotide (SOM230) in a Male Population Who Are Hyperendemic Hepatitis B/C and Chronic Kidney Disease: An Open-Label, Phase I Study

BACKGROUND

In patients with kidney or hepatic diseases, an increment of circulating pasireotide is also expected. Therefore, this open-label, phase I study aimed to evaluate the pharmacokinetic profiles and safety of subcutaneous (SC) and long-acting release (LAR) intramuscular injections of pasireotide in male Taiwanese volunteers who are hyperendemic hepatitis B/C and chronic kidney disease (CKD).

METHODS

A total of 45 male volunteers were randomized to receive one of nine treatment sequences, involving a single subcutaneous injection of 300, 600, or 900 μg pasireotide, a multiple SC injection of the same dosage of pasireotide [300, 600, or 900 μg, twice daily (b.i.d.) for 4 days and a single dose for 1 day], and a single dose of 20, 40, or 60 mg LAR pasireotide intramuscular injection. The pasireotide SC and LAR formulations were prepared and supplied to the study center by Novartis. Pharmacokinetic parameters were assessed from both formulations. All adverse events that occurred in participants throughout the study period, including abnormalities in fasting levels of glucose, insulin, and glucagon, as well as laboratory measurements and electrocardiograms, were recorded.

RESULTS

Analysis of plasma concentration over time revealed a rapid absorption of pasireotide, with a maximal concentration at 0.5 h after SC injection(s) of pasireotide (300-900 µg). Following a single dose of pasireotide LAR (20-60 mg), a sustained release was observed following an initial increase on day 1, a plateau around day 20, and a decline over the next 7 weeks.

CONCLUSIONS

Both pasireotide formulations showed dose-proportional pharmacokinetics and 300-900 μg of SC pasireotide and 20-60 mg LAR pasireotide treatment showed favorable safety profiles and was well-tolerated when administered in male Taiwanese volunteers who are hyperendemic hepatitis B/C and CKD.

Clinical Management of Acromegaly: Therapeutic Frontiers and New Perspectives for Somatostatin Receptor Ligands (SRLs)

Somatostatin receptor ligands (SRLs) represent a true milestone in the medical therapy for acromegaly. The first-generation SRLs (FG-SRLs), octreotide and lanreotide, have demonstrated good efficacy in disease control and tumor shrinkage, and are still considered first-line medical therapies. The development of long-acting release (LAR) formulations has certainly improved the therapeutic tolerability of these drugs, although many patients still experience therapy-related burden. As such, new formulations have recently been developed to improve adherence and therapeutic efficacy and more solutions are on the way. In the case of FG-SRL-resistant disease, pasireotide, the only second generation SRL currently available, demonstrated superiority in disease control and tumor shrinkage compared to FG-SRLs. However, its use in clinical practice is still limited due to concern for impairment in glucose homeostasis. In this review, we discuss the news about the present and future role of SRLs in acromegaly, exploring the therapeutical frontiers of this drug class. Moreover, we provide practical guidance on the use of pasireotide, based on the data in the literature and our clinical experience.

Electrophysiological features in acromegaly: re-thinking the arrhythmic risk?

BACKGROUND

Acromegaly is disease associated with a specific cardiomyopathy. Hitherto, it has been widely understood that acromegaly carries an increased risk of arrhythmia.

PURPOSE

In this review we show that evidences are limited to a small number of case-control studies that reported increased rates of premature ventricular beats (PVB) but no more significant arrhythmia. In contrast, there are several studies that have reported impaired preclinical markers of arrhythmia, including reduced heart rate variability, increased late potentials, QT interval dispersion, impaired heart rate recovery after physical exercise and left ventricular dysynchrony. Whilst these markers are associated with an adverse cardiovascular prognosis in the general population, they do not have a high independent positive predictive accuracy for arrhythmia. In acromegaly, case reports have described sudden cardiac death, ventricular tachyarrhythmia and advanced atrio-ventricular block that required implantation of a cardio-defibrillator or permanent pacemaker. Treatment with somatostatin analogues can reduce cardiac dysrhythmia in some cases by reducing heart rate, PVBs and QT interval. Pegvisomant reduces mean heart rate. Pasireotide is associated with QT prolongation. In the absence of good quality data on risk of arrhythmia in acromegaly, the majority of position statements and guidelines suggest routine 12-lead electrocardiography (ECG) and transthoracic echocardiography (TTE) in every patient at diagnosis and then follow up dependent on initial findings.

A Consensus on the Diagnosis and Treatment of Acromegaly Comorbidities: An Update

OBJECTIVE

The aim of the Acromegaly Consensus Group was to revise and update the consensus on diagnosis and treatment of acromegaly comorbidities last published in 2013.

PARTICIPANTS

The Consensus Group, convened by 11 Steering Committee members, consisted of 45 experts in the medical and surgical management of acromegaly. The authors received no corporate funding or remuneration.

EVIDENCE

This evidence-based consensus was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence following critical discussion of the current literature on the diagnosis and treatment of acromegaly comorbidities.

CONSENSUS PROCESS

Acromegaly Consensus Group participants conducted comprehensive literature searches for English-language papers on selected topics, reviewed brief presentations on each topic, and discussed current practice and recommendations in breakout groups. Consensus recommendations were developed based on all presentations and discussions. Members of the Scientific Committee graded the quality of the supporting evidence and the consensus recommendations using the GRADE system.

CONCLUSIONS

Evidence-based approach consensus recommendations address important clinical issues regarding multidisciplinary management of acromegaly-related cardiovascular, endocrine, metabolic, and oncologic comorbidities, sleep apnea, and bone and joint disorders and their sequelae, as well as their effects on quality of life and mortality.

Thorough QT (TQT) studies: concordance with torsadogenesis and an evolving cardiac safety testing paradigm

Since 2005, when the International Conference on Harmonisation (ICH) E14 guideline was adopted, no drug has been withdrawn because of QTc prolongation or torsade de pointes arrhythmia. There are, however, costs associated with this success. In addition to the time and money invested, thorough QT (TQT) studies have limited the efficiency of the drug development pipeline. In this paper, we discuss the relevance of TQT trials as a tool for proarrhythmic risk prediction as a part of the debate regarding their usefulness.

Phase I trial of combination of FOLFIRI and pasireotide, a somatostatin analogue, in advanced gastrointestinal malignancies

INTRODUCTION

Pasireotide (SOM230) is a somatostatin analog with high binding affinity for somatostatin receptors including sst1, 2, 3 and 5 and inhibit insulin like growth factor-1. Blocking of IGF-1 receptor (IGF-1R) in combination with cytotoxic chemotherapy has demonstrated additive or synergistic activity in pre-clinical models. This study aimed to evaluate the maximum tolerated dose (MTD) of pasireotide in combination with standard FOLFIRI (5-fluorouracil, leucovorin and irinotecan) regimen in patients with gastrointestinal malignancies.

METHODS

This was a phase 1, 3 + 3 design, open-label dose escalation study conducted in sequential cohorts to determine the MTD of pasireotide in combination with FOLFIRI. All patients had gastrointestinal malignancies and were previously treated. Sixteen patients enrolled in five dose cohorts at pasireotide doses of 40, 60, 80, 100 and 120 mg were evaluated for safety and tolerability of the combination.

RESULTS

The tumor types of the enrolled subjects included esophageal (n = 5), biliary tract (n = 3), colon (n = 3), gastric (n = 2), pancreatic (n = 1), anal (n = 1) and small bowel (n = 1). No dose limiting toxicities were observed. The most common adverse events related to the study treatment included hyperglycemia (81 %), neutropenia (62 %), thrombocytopenia (44 %), anorexia (44 %), dehydration (25 %) and elevated alkaline phosphatase (25 %). Two patients had partial response and 7 patients had stable disease. Plasma levels of IGF-1 and IGFBP-3 were significantly reduced after treatment with pasireotide.

DISCUSSION

Combination of pasireotide and FOLFIRI has manageable safety profile and is feasible in patients with gastrointestinal malignancies. Preliminary signals of activity were observed. Larger phase II trials are warranted.

Osilodrostat (LCI699), a potent 11β-hydroxylase inhibitor, administered in combination with the multireceptor-targeted somatostatin analog pasireotide: A 13-week study in rats

The somatostatin analog pasireotide and the 11β-hydroxylase inhibitor osilodrostat (LCI699) reduce cortisol levels by distinct mechanisms of action. There exists a scientific rationale to investigate the clinical efficacy of these two agents in combination. This manuscript reports the results of a toxicology study in rats, evaluating different doses of osilodrostat and pasireotide alone and in combination. Sixty male and 60 female rats were randomized into single-sex groups to receive daily doses of pasireotide (0.3mg/kg/day, subcutaneously), osilodrostat (20mg/kg/day, orally), osilodrostat/pasireotide in combination (low dose, 1.5/0.03mg/kg/day; mid-dose, 5/0.1mg/kg/day; or high dose, 20/0.3mg/kg/day), or vehicle for 13weeks. Mean body-weight gains from baseline to Week 13 were significantly lower in the pasireotide-alone and combined-treatment groups compared to controls, and were significantly higher in female rats receiving osilodrostat monotherapy. Osilodrostat and pasireotide monotherapies were associated with significant changes in the histology and mean weights of the pituitary and adrenal glands, liver, and ovary/oviduct. Osilodrostat alone was associated with adrenocortical hypertrophy and hepatocellular hypertrophy. In combination, osilodrostat/pasireotide did not exacerbate any target organ changes and ameliorated the liver and adrenal gland changes observed with monotherapy. Cmax and AUC0-24h of osilodrostat and pasireotide increased in an approximately dose-proportional manner. In conclusion, the pasireotide and osilodrostat combination did not exacerbate changes in target organ weight or toxicity compared with either monotherapy, and had an acceptable safety profile; addition of pasireotide to the osilodrostat regimen may attenuate potential adrenal gland hyperactivation and hepatocellular hypertrophy, which are potential side effects of osilodrostat monotherapy.

Aspiration sclerotherapy combined with pasireotide to improve reduction of large symptomatic hepatic cysts (SCLEROCYST): study protocol for a randomized controlled trial

BACKGROUND

Aspiration sclerotherapy is an effective therapeutic option for large symptomatic hepatic cysts. However, incomplete cyst reduction following aspiration sclerotherapy is frequently reported. Strong post-procedural cyst fluid secretion by cholangiocytes, which line the epithelium of the hepatic cyst, seems to be associated with lower reduction rates. Previous studies showed that somatostatin analogues curtail hepatic cyst fluid production. This trial will evaluate the effect of aspiration sclerotherapy combined with the somatostatin analogue pasireotide on cyst reduction. By combining treatment modalities we aim to improve cyst reduction leading to greater symptomatic relief and reduced rates of cyst recurrence.

METHODS/DESIGN

This single center, randomized, double-blind, placebo-controlled clinical trial evaluates the additional effect of pasireotide when combined with aspiration sclerotherapy in patients with a large (>5 cm) symptomatic hepatic cyst. A total of 34 participants will be randomized in a 1:1 ratio. In the active arm, patients will receive pasireotide (long-acting release, 60 mg injection) two weeks prior to and two weeks following aspiration sclerotherapy. Patients in the control arm will receive placebo injections at corresponding intervals. The primary outcome is proportional cyst diameter reduction four weeks after aspiration sclerotherapy compared to baseline measurements, obtained by ultrasonography. As secondary outcomes, proportional volume reduction, recurrence, symptomatic relief and improvement of health-related quality of life will be assessed. Furthermore, safety and tolerability of the combination of pasireotide and aspiration sclerotherapy will be evaluated.

DISCUSSION

This trial aims to improve efficacy of aspiration sclerotherapy by a combined approach of two treatment modalities. We hypothesize that pasireotide will decrease fluid re-accumulation after aspiration sclerotherapy, leading to effective hepatic cyst reduction and symptomatic relief.

TRIALS REGISTRATION

This trial is registered with ClinicalTrials.gov (identifier: NCT02048319 ; registered on 6 January 2014) and EudraCT (identifier: 2013-003168-29; registered on 16 August 2013).

Safety Pharmacology Evaluation of Biopharmaceuticals

Biotechnology-derived pharmaceuticals or biopharmaceuticals (BPs) are molecules such as monoclonal antibodies, soluble/decoy receptors, hormones, enzymes, cytokines, and growth factors that are produced in various biological expression systems and are used to diagnose, treat, or prevent various diseases. Safety pharmacology (SP) assessment of BPs has evolved since the approval of the first BP (recombinant human insulin) in 1982. This evolution is ongoing and is informed by various international harmonization guidelines. Based on these guidelines, the potential undesirable effect of every drug candidate (small molecule or BP) on the cardiovascular, central nervous, and respiratory systems, referred to as the "core battery," should be assessed prior to first-in-human administration. However, SP assessment of BPs poses unique challenges such as choice of test species and integration of SP parameters into repeat-dose toxicity studies. This chapter reviews the evolution of SP assessment of BPs using the approval packages of marketed BPs and discusses the past, current, and new and upcoming approach and methods that can be used to generate high-quality data for the assessment of SP of BPs.