Cost-Utility of Acromegaly Pharmacological Treatments in a French Context

Cost-effectiveness analysis of second-line medical therapies in acromegaly: a real-life study

Introduction

Acromegaly is an uncommon disease with important comorbidity and economic cost. Although the pharmacological cost of second-line treatment for refractory acromegaly has been theoretically analyzed, real-life studies are needed.

Objectives

To assess the use of pasireotide and pegvisomant in a third-level center under routine clinical practice.

Methods

Acromegaly patients that had been treated with pasireotide and/or pegvisomant were included in (A) a cross-sectional study (two years after starting these drugs) to analyze the cost of acromegaly, hormone replacement, and type 2 diabetes mellitus (T2DM) treatments, and the cost of surgery and radiotherapy; and (B) a retrospective cohorts study (May 2006-October 2024) to analyze efficacy, safety (adverse events, fasting glucose, glycated hemoglobin, and T2DM diagnosis), and dose evolution. Descriptive statistics were 10% trimmed means and standard deviation. Two-tailed hypothesis testing with Yuen's t and Fisher's test had a P < 0.05 significance.

Results

25 participants were included in the transversal study and 31 participants in the longitudinal study. A typical patient with a poorly granulated GH-producing adenoma underwent in-center surgery once and received radiotherapy. In the transversal study, total pharmacological cost was 34,139.29 (13,472.09) €/person/year, with 33,874.88 (13,468.36) €/person/year for second-line acromegaly drugs. Pasireotide displayed 9,423.26 €/person/year worth of savings (P = .12), reaching 30,415.98 €/person/year at high dose (P < 0.001). In the longitudinal study, pasireotide dose was reduced (P = .06) regardless of treatment modality. Pasireotide affected carbohydrate metabolism (P = .001), but the effect was generally mild.

Conclusions

Pasireotide was found to be a more cost-effective option in patients with first-line treatment failure.

Acromegaly: diagnostic challenges and individualized treatment

INTRODUCTION

Acromegaly is due in almost all cases to a GH-secreting pituitary tumor. GH and IGF-1 excesses lead to its multi-system clinical manifestations and comorbidities. Acromegaly is under-diagnosed and typically presents with advanced disease. When early or mild, clinical recognition and biochemical confirmation are especially challenging. Individualized treatment may optimize patient outcome.

AREAS COVERED

This review covers challenges to diagnosing acromegaly and reviews therapies for acromegaly with a focus on those aspects that can be individualized.

EXPERT OPINION

The first step in diagnosing acromegaly is recognizing it clinically. To improve this, increase awareness and education of the general population and healthcare professionals about the acromegaly phenotype is needed. Once suspected clinically, IGF-1 measurement is the initial step in making the biochemical diagnosis. GH may be < 1.0 µg/L after oral glucose suppression in early/mild cases. GH and IGF-1 should be considered in concert. Providers should be aware of conditions that can alter GH and IGF-1 levels and each assay's performance. An individualized treatment approach is best employed. Surgery is preferred as initial treatment and medical therapy as initial adjuvant therapy. In individualizing therapy, the advantages and disadvantages of each option and predictors of response to them should be considered.

Growth hormone receptor antagonist pegvisomant and its role in the medical therapy of growth hormone excess

Pegvisomant is a growth-hormone (GH) receptor antagonist that prevents the formation of the active heterotrimer of the dimerised GH receptor and the GH molecule necessary for downstream signal transduction. Over the past 20 years, it has become a key therapeutic option for physicians treating syndromes of GH/IGF-1 excess. Sufficient longitudinal follow-up data suggest that it can be deemed both safe and effective. It is the drug with the greatest potential for achieving an amelioration of the biochemical effects of GH excess with a corresponding normalisation of IGF-1 levels; however, insufficient dose titration has lessened real-world therapeutic outcomes. Theoretical concerns about stimulating tumour growth have been resolved as this has not been observed, while derangement of liver enzymes and local skin-related adverse reactions may occur in a minority of the patients. It may be a particularly impactful medication for the treatment of children, young people, and those with inherited disorders of GH excess, where other treatment modalities often fail. Combination therapy of pegvisomant with first- and second-generation somatostatin receptor ligands or with dopamine agonists remains an ongoing area of interest and research. High cost remains a barrier to the use of pegvisomant in many settings.

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.

The socioeconomic burden of acromegaly

Acromegaly is a rare and insidious disease characterized by chronic excess growth hormone, leading to various morphological changes and systemic complications. Despite its low prevalence, acromegaly poses a significant socioeconomic burden on patients and healthcare systems. This review synthesizes the current state of knowledge on the psychosocial burden, disability, impact on daily life, and cost of acromegaly disease, focusing on the quality of life, partnership, medical care and treatment afflictions, participation in daily activities, professional and leisure impairment, and cost of treatment for acromegaly and its comorbidities. It also examines management strategies, coping mechanisms, and interventions aimed at alleviating this burden. A comprehensive understanding of the extent of the socioeconomic burden in acromegaly is crucial to develop effective strategies to improve treatment and care. Further research is warranted to explore the myriad factors contributing to this burden, as well as the efficacy of interventions to alleviate it, ultimately enhancing the quality of life for patients with acromegaly.

Structure and function of a dual antagonist of the human growth hormone and prolactin receptors with site-specific PEG conjugates

Human growth hormone (hGH) is a pituitary-derived endocrine protein that regulates several critical postnatal physiologic processes including growth, organ development, and metabolism. Following adulthood, GH is also a regulator of multiple pathologies like fibrosis, cancer, and diabetes. Therefore, there is a significant pharmaceutical interest in developing antagonists of hGH action. Currently, there is a single FDA-approved antagonist of the hGH receptor (hGHR) prescribed for treating patients with acromegaly and discovered in our laboratory almost 3 decades ago. Here, we present the first data on the structure and function of a new set of protein antagonists with the full range of hGH actions-dual antagonists of hGH binding to the GHR as well as that of hGH binding to the prolactin receptor. We describe the site-specific PEG conjugation, purification, and subsequent characterization using MALDI-TOF, size-exclusion chromatography, thermostability, and biochemical activity in terms of ELISA-based binding affinities with GHR and prolactin receptor. Moreover, these novel hGHR antagonists display distinct antagonism of GH-induced GHR intracellular signaling in vitro and marked reduction in hepatic insulin-like growth factor 1 output in vivo. Lastly, we observed potent anticancer biological efficacies of these novel hGHR antagonists against human cancer cell lines. In conclusion, we propose that these new GHR antagonists have potential for development towards multiple clinical applications related to GH-associated pathologies.

Patient-reported outcomes in patients with acromegaly treated with pegvisomant in the ACROSTUDY extension: A real-world experience

PURPOSE

To report the effects of pegvisomant (PEGV) treatment on patient-reported outcomes in acromegaly patients.

METHODS

We conducted an extension study of an open-label, multinational, non-interventional study (ACROSTUDY) evaluating the long-term safety and efficacy of PEGV for acromegaly in routine clinical practice. Enrolled patients were rollover patients from ACROSTUDY, or treatment naïve/semi-naïve (NSN; no PEGV within 6 months of enrollment). Exploratory efficacy endpoints were changes in symptoms with the Patient-Assessed Acromegaly Symptom Questionnaire (PASQ) and quality of life with the Acromegaly Quality of Life questionnaire (AcroQoL) analyzed by controlled or uncontrolled IGF-I levels. Results were analyzed in all patients, in NSN patient subgroup, and by diabetes status.

RESULTS

A total of 544 patients with acromegaly were enrolled, including 434 rollover subjects from ACROSTUDY and 110 NSN patients. Mean PEGV treatment duration was 7.8 years (range, 0-19.6 years). Overall, the majority of PASQ scores improved over time, but there was no significant difference between IGF-I controlled or uncontrolled groups. In the NSN subgroup, most PASQ and AcroQoL scores remained similar to baseline up to 1 year, regardless of IGF-I control. Patients with diabetes reported better PASQ scores over time with PEGV treatment, regardless of IGF-I control. IGF-I normalization increased from 10% of patients at baseline to more than 78% at year 10, with a mean daily PEGV dose of 18.7 mg.

CONCLUSIONS

Overall, patients treated with PEGV had small improvements in PASQ. While IGF-I normalization increased with PEGV treatment, IGF-I control had no effects on PASQ and AcroQoL scores.