Lanreotide Autogel 120 mg at extended dosing intervals in patients with acromegaly biochemically controlled with octreotide LAR: the LEAD study

Acromegaly Type 1: A Representative Patient

A 46-year-old woman was troubled by a 3-year history of constant headaches and arthralgias. She was treated with paracetamol with no symptom resolution. An abnormal fasting glucose level prompted endocrine evaluation. On physical examination, she casually mentioned that her wedding ring no longer fit, and she also confirmed an increase in shoe size. There were no characteristic facial features for acromegaly and there was no evidence of acral enlargement. Biochemical evaluation, including insulin-like growth factor type 1 (IGF-1) measurement and oral glucose loading with growth hormone (GH) measurement confirmed excess GH production and a diagnosis of acromegaly. Pituitary magnetic resonance imaging showed a central pituitary microadenoma. After transsphenoidal surgical resection, tissue immunohistochemistry revealed a densely granulated somatotroph adenoma. Currently, the patient is asymptomatic with biochemical disease control, normal fasting glucose levels, and no pituitary hormone deficiencies. This patient is illustrative of a type 1 acromegaly with mild clinical manifestations. Clinicians should be aware of acromegaly subtypes to avoid delay in diagnosis and to individualize therapy.

A systematic literature review to evaluate extended dosing intervals in the pharmacological management of acromegaly

PURPOSE

This systematic literature review investigated whether extended dosing intervals (EDIs) of pharmacological acromegaly treatments reduce patient burden and costs compared with standard dosing, while maintaining effectiveness.

METHODS

MEDLINE/Embase/the Cochrane Library (2001-June 2021) and key congresses (2018-2021) were searched and identified systematic literature review bibliographies reviewed. Included publications reported on efficacy/effectiveness, safety and tolerability, health-related quality of life (HRQoL), and patient-reported and economic outcomes in longitudinal/cross-sectional studies in adults with acromegaly. Interventions included EDIs of pegvisomant, cabergoline, and somatostatin receptor ligands (SRLs): lanreotide autogel/depot (LAN), octreotide long-acting release (OCT), pasireotide long-acting release (PAS), and oral octreotide; no comparator was required.

RESULTS

In total, 35 publications reported on 27 studies: 3 pegvisomant monotherapy, 11 pegvisomant combination therapy with SRLs, 9 LAN, and 4 OCT; no studies reported on cabergoline, PAS, or oral octreotide at EDIs. Maintenance of normal insulin-like growth factor I (IGF-I) was observed in ≥ 70% of patients with LAN (1 study), OCT (1 study), and pegvisomant monotherapy (1 study). Achievement of normal IGF-I was observed in ≥ 70% of patients with LAN (3 studies) and pegvisomant in combination with SRLs (4 studies). Safety profiles were similar across EDI and standard regimens. Patients preferred and were satisfied with EDIs. HRQoL was maintained and cost savings were provided with EDIs versus standard regimens.

CONCLUSIONS

Clinical efficacy/effectiveness, safety, and HRQoL outcomes in adults with acromegaly were similar and costs lower with EDIs versus standard regimens. Physicians may consider acromegaly treatment at EDIs, especially for patients with good disease control.

Self-reported symptoms in patients with acromegaly: a 6-month follow-up in a single neurosurgical center

Acromegaly is characterized by hypersecretion of growth hormone (GH) and insulin-like growth factor 1 (IGF-1), accompanied by a compromise in the perception of wellness. The Patient-Assessed Acromegaly Symptom Questionnaire (PASQ) is relevant to assessing signs and symptoms but is mainly used to evaluate the efficacy of a pharmacological intervention. To explore the perioperative variation in symptom severity, the divergence between subgroups stratified according to clinical outcomes or treatment modalities, and the interaction between symptom scores and clinical indices, we prospectively recruited 106 patients with acromegaly from 2016 to 2018. Oral glucose tolerance and GH tests were performed, and PASQ was administered before treatment and 6 months postoperatively. Patients were divided into active (n = 49) and remission (n = 57) groups according to postoperative GH and IGF-1 levels. PASQ scores and GH and IGF-1 levels decreased significantly postoperatively in both groups. A significantly higher preoperative headache score and greater extent of decrease in arthralgia were seen in the active and remission groups, respectively. No significant variation in PASQ scores was found between patients receiving surgery alone and those receiving preoperative somatostatin analogs. Preoperative fasting GH (GH0) levels were positively correlated with preoperative excessive perspiration. Further regression analyses validated the variation in GH0 as a noteworthy determinant of the extent of change in soft-tissue swelling, excessive perspiration, fatigue, and total PASQ scores. Patient-reported symptoms were substantially alleviated after surgery, independent of endocrine remission or use of preoperative somatostatin. A GH level decrease was a notable coefficient for PASQ scores.

Subclinical acromegaly: to treat or not to treat?

Patients with acromegaly usually present with the classical signs of acromegaly, whereas patients without the specific signs or symptoms are rarely diagnosed. This unique entity can be named "subclinical acromegaly". This was a retrospective study. Our study group consisted of 6 patients (4 females) with incidentally diagnosed acromegaly, most following head MRI for unrelated reasons and without the specific signs of acromegaly. Mean age at diagnosis was 48.8 ± 19.2 years. Baseline IGF-1 ranged between 1.3-2.0 × upper limit of normal (ULN). MRI depicted a pituitary microadenoma in 5 patients, and one patient presented with a 12 mm intra-sellar macroadenoma. Mean calculated SAGIT clinical score was 4.8. Three patients underwent trans-sphenoidal resection; two achieved hormonal remission and one improved but did not normalize IGF-1 following surgery. Four patients (including one following surgery) were given somatostatin analogs, and three normalized IGF-1. Several patients improved clinically following treatment, reporting improvement in snoring, hypertension, or weight loss, and pituitary adenoma decreased in size in 2 patients that responded to medical treatment. We report a series of 6 patients with very mild and subclinical acromegaly. It is uncertain whether all such patients will gain clinical benefit from treatment, but most experienced clinical improvement due to treatment.

Acromegaly: pathogenesis, diagnosis, and management

Growth hormone-secreting pituitary adenomas that cause acromegaly arise as monoclonal expansions of differentiated somatotroph cells and are usually sporadic. They are almost invariably benign, yet they can be locally invasive and show progressive growth despite treatment. Persistent excess of both growth hormone and its target hormone insulin-like growth factor 1 (IGF-1) results in a wide array of cardiovascular, respiratory, metabolic, musculoskeletal, neurological, and neoplastic comorbidities that might not be reversible with disease control. Normalisation of IGF-1 and growth hormone are the primary therapeutic aims; additional treatment goals include tumour shrinkage, relieving symptoms, managing complications, reducing excess morbidity, and improving quality of life. A multimodal approach with surgery, medical therapy, and (more rarely) radiation therapy is required to achieve these goals. In this Review, we examine the epidemiology, pathogenesis, diagnosis, complications, and treatment of acromegaly, with an emphasis on the importance of tailoring management strategies to each patient to optimise outcomes.

Pharmacological and safety profile of a prolonged-release lanreotide formulation in acromegaly

BACKGROUND

Patients with acromegaly require lifelong medication; a longer dosing interval would reduce treatment burden. This study investigated the pharmacokinetics, pharmacodynamics and safety profile of a new prolonged-release formulation (PRF) of lanreotide every 12 weeks.

RESEARCH DESIGN AND METHODS

In this multicenter, open-label, dose-ascending study, cohorts of nine patients with acromegaly received single doses of lanreotide PRF according to a 3 + 3 + 3 scheme in order to determine the maximum tolerated dose (MTD). Following a 12-week treatment period, patients were followed up for a further 12 weeks. Serum lanreotide, insulin-like growth factor-1 and growth hormone concentrations were analyzed. Adverse events were monitored throughout the study.

RESULTS

The MTD was not reached. Peak lanreotide serum concentration values were similar in all cohorts, whereas area under the curve values from time zero to 85 days increased but were not dose-proportional. The apparent elimination half-life of lanreotide PRF was approximately 54-63 days, in line with the expected prolonged-release characteristics. Growth hormone and insulin-like growth factor-1 levels were generally stable.

CONCLUSIONS

The safety and tolerability profile was in-line with the known safety profile of lanreotide autogel. Lanreotide PRF was well tolerated and the pharmacokinetic profile suggests that a dosing interval of 12 weeks could be achievable.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT02396953; EudraCT 2014-002389-62.

Patient and Healthcare Provider Perspectives of First-Generation Somatostatin Analogs in the Management of Neuroendocrine Tumors and Acromegaly: A Systematic Literature Review

Introduction

Somatostatin analogs (SSAs) are used to treat neuroendocrine tumors (NETs) and acromegaly. Two first-generation SSAs, octreotide long-acting release (OCT LAR) and lanreotide autogel/depot (LAN), are available. A systematic literature review (SLR) was conducted to investigate which characteristics beyond efficacy are most important in patient and healthcare practitioner (HCP) experience of LAN and OCT when used to treat acromegaly and NETs.

Methods

MEDLINE, Embase, the Cochrane Library, and Database of Abstracts of Reviews of Effect were searched from database inception to January 2019 with terms for first-generation SSAs, NETs, acromegaly, preferences, decision-making, and human factors. Key congresses in 2016–2018 and SLR bibliographies were hand-searched. Two independent reviewers screened articles at title/abstract and full-text stage. Publications fulfilling pre-specified inclusion criteria reported patient or HCP perspectives of LAN or OCT, or any factors affecting treatment perspectives for NETs or acromegaly.

Results

A total of 1110 unique records were screened, of which 21 studies were included, reporting from the perspectives of patients (n = 18) and/or HCPs (n = 9). Perspectives were collected using shared decision-making frameworks, questionnaires, informal patient opinion, and a Delphi panel. Where patient preference was specifically reported, LAN was preferred in 4/5 studies and OCT LAR in 1/5. Common factors underlying treatment experience included technical problems with injections and associated pain, emotional quality/anxiety of injections, time and convenience of treatment administration, and independence. Immediate aspects of injections appeared most important to patients, though the possibilities of extended dosing intervals and self-/partner-injection with LAN were also notable factors.

Conclusions

Study outcomes favored LAN in this SLR, with factors surrounding injection administration most influential in treatment experience. The findings of this SLR provide a basis that could inform development of decision-making criteria, with patient and HCP treatment perspectives considered. Future studies should utilize a common method to report preference and associated drivers.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-020-01600-x.

A Pituitary Society update to acromegaly management guidelines

Guidelines and consensus statements ensure that physicians managing acromegaly patients have access to current information on evidence-based treatments to optimize outcomes. Given significant novel recent advances in understanding acromegaly natural history and individualized therapies, the Pituitary Society invited acromegaly experts to critically review the current literature in the context of Endocrine Society guidelines and Acromegaly Consensus Group statements. This update focuses on how recent key advances affect treatment decision-making and outcomes, and also highlights the likely role of recently FDA-approved therapies as well as novel combination therapies within the treatment armamentarium.

Improvement in Symptoms and Health-Related Quality of Life in Acromegaly Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Whereas biochemical response is often used as a primary study outcome, improvement in symptoms and health-related quality of life (HRQoL) is the relevant goal for patients to consider treatment successful. We performed a systematic review and meta-analysis to assess the effect of treatment on symptoms and HRQoL in acromegaly.

METHODS

Seven electronic databases were searched for longitudinal studies assessing patient-reported symptoms or HRQoL in acromegaly. Meta-analyses were performed to assess differences during treatment for the Acromegaly Quality of Life Questionnaire (AcroQoL) and Patient-Assessed Acromegaly Symptom Questionnaire (PASQ), and standardized mean difference (SMD) for individual symptoms (interpretation: 0.2 small, 0.5 moderate, and 0.8 large effect). Treatment-naive and previously treated patients were assessed separately.

RESULTS

Forty-six studies with 3301 patients were included; 24 contributed to quantitative analyses. Thirty-six studies used medication as main treatment, 1 transsphenoidal adenomectomy, and 9 various treatments. Symptoms and HRQoL both improved: AcroQoL increased 2.9 points (95% CI, 0.5 to 5.3 points), PASQ decreased -2.3 points (95% CI, -1.3 to -3.3 points), and individual symptom scores decreased for paresthesia -0.9 (95% CI, -0.6 to -1.2), hyperhidrosis -0.4 (95% CI, -0.1 to -0.6), fatigue -0.3 (95% CI, -0.1 to -0.6), arthralgia -0.3 (95% CI, -0.1 to -0.5), headache -0.3 (95% CI, 0.0 to -0.6), and soft-tissue swelling -0.2 (95% CI, 0.0 to -0.4).

CONCLUSION

Symptoms and HRQoL improved during acromegaly treatment. Consensus is needed on which symptoms should be included in a potential core outcome set, taking into account symptom frequency, severity, and sensitivity to change, which can be used in clinical practice and as outcome in trials.

Effectiveness of lanreotide autogel 120 mg at extended dosing intervals for acromegaly

PURPOSE

Recent data indicate that extended dosing intervals (EDIs) with lanreotide autogel 120 mg are effective and well-received among patients with acromegaly who have achieved biochemical control with monthly injections of long-acting somatostatin analogues (SSAs). We further evaluated the effectiveness of lanreotide autogel 120 mg delivered at EDIs (>4 weeks) in routine clinical practice.

METHODS

Cross-sectional, multicentre, observational study conducted to determine the effectiveness-measured by control of serum insulin-like growth factor 1 (IGF-1)-of lanreotide autogel 120 mg at dosing intervals >4 weeks for ≥6 months in selected patients with acromegaly treated in routine clinical practice (NCT02807233). Secondary assessments included control of growth hormone (GH) levels, treatment adherence, patient satisfaction, and quality of life (QoL) using validated questionnaires (EQ-5D, AcroQoL, and TSQM-9). Patients who received radiotherapy within the last 6 months were excluded.

RESULTS

Among 109 patients evaluated, mean (SD) age was 59.1 (13.2) years. IGF-1 values were normal (mean [SD]: 175.0 [74.5], 95% CI: 160.8 -189.1) in 91.7% of cases and normal in 91.4% of patients without previous radiotherapy treatment (n = 81). GH levels were ≤2.5 and ≤1 ng/mL, respectively, in 80.6% and 58.3%. Most patients were treated either every 5-6 (57.8%) or 7-8 weeks (38.5%), with 2.8% treated greater than every 8 weeks. The mean AcroQoL score was 63.0 (20.1). The mean global treatment satisfaction score (TSQM-9) was 75.1 (16.6). Treatment adherence (defined as no missed injections) was 94.5%.

CONCLUSION

Lanreotide autogel 120 mg at intervals of >4 weeks provided IGF-1 control in more than 90% of patients with acromegaly. Treatment satisfaction and adherence were good. These findings support use of extended dosing intervals in patients who have achieved good biochemical control with long-acting SSAs.

Maintenance of Acromegaly Control in Patients Switching From Injectable Somatostatin Receptor Ligands to Oral Octreotide

PURPOSE

The phase 3 CHIASMA OPTIMAL trial (NCT03252353) evaluated efficacy and safety of oral octreotide capsules (OOCs) in patients with acromegaly who previously demonstrated biochemical control while receiving injectable somatostatin receptor ligands (SRLs).

METHODS

In this double-blind study, patients (N = 56) stratified by prior SRL dose were randomly assigned 1:1 to OOC or placebo for 36 weeks. The primary end point was maintenance of biochemical control at the end of treatment (mean insulin-like growth factor 1 [IGF-1] ≤ 1.0 × upper limit of normal [ULN]; weeks 34 and 36). Time to loss of IGF-1 response and proportion requiring reversion to injectable SRLs were assessed as broader control measures.

RESULTS

Mean IGF-1 measurements were 0.80 and 0.97 × ULN for OOC and 0.84 and 1.69 × ULN for placebo, at baseline and end of treatment, respectively. Mean growth hormone (GH) changed from 0.66 to 0.60 ng/mL for OOCs and 0.90 to 2.57 ng/mL for placebo. Normalization of IGF-1 levels (≤ 1.0 × ULN) was maintained in 58.2% for OOCs vs 19.4% for placebo (P = .008); GH levels were maintained (< 2.5 ng/mL) in 77.7% for OOC vs 30.4% for placebo (P = .0007). Median time to loss of response (IGF-1 > 1.0 or ≥ 1.3 × ULN definitions) for patients receiving placebo was 16 weeks; for patients receiving OOCs, it was not reached for both definitions during the 36-week trial (P < .0001). Of the patients in the OOC group, 75% completed the trial on oral therapy. The OOC safety profile was consistent with previous SRL experience.

CONCLUSIONS

OOCs may be an effective therapy for patients with acromegaly who previously were treated with injectable SRLs.

Efficacy and safety of lanreotide autogel compared with lanreotide 40 mg prolonged release in Chinese patients with active acromegaly: results from a phase 3, prospective, randomized, and open-label study (LANTERN)

BACKGROUND

Lanreotide autogel is a somatostatin analog (SSA) approved for the treatment of acromegaly in 73 countries worldwide; however, it is not yet approved in China. The aim of this study was to evaluate the efficacy and safety of lanreotide autogel compared with lanreotide 40 mg prolonged release (PR) in Chinese patients with active acromegaly.

METHODS

LANTERN was a phase 3, randomized, open-label, non-inferiority study. Patients with active acromegaly who had undergone surgery ≥3 months prior, or were unlikely or unable to undergo surgery, were treated with lanreotide autogel 60/90/120 mg (monthly deep subcutaneous injection) or lanreotide 40 mg PR (intramuscular injection every 7, 10, or 14 days) for 32 weeks. Primary endpoint was mean change-from-baseline in age-adjusted insulin-like growth factor-1 (IGF-1) standard deviation scores (SDS) at the end-of-study. Secondary endpoints included: growth hormone (GH) levels ≤2.5 μg/L or ≤ 1.0 μg/L, ≥20% reduction in tumor volume (TV) and safety.

RESULTS

In total, 128 patients were randomized and received study treatment. Lanreotide autogel was non-inferior to lanreotide 40 mg PR: treatment difference (95% CI) for IGF-1 SDS between groups was - 0.32 (- 0.74, 0.11; per protocol population) and - 0.27 (- 0.63, 0.09; intention-to-treat [ITT] population), respectively. Reductions in IGF-1 (- 6.453 vs - 7.003) and GH levels (- 9.548 μg/L vs - 13.182 μg/L), and the proportion of patients with ≥1 acromegaly symptom (- 20.3% vs - 32.5%) were observed from baseline to end-of-study in lanreotide autogel and lanreotide 40 mg PR groups, respectively. In the lanreotide autogel group, 45.5% (25/55) patients achieved ≥20% reduction in TV compared with 50.9% (25/53) in lanreotide 40 mg PR group (ITT). Safety profiles were similar in both treatment groups.

CONCLUSIONS

Lanreotide autogel was non-inferior to lanreotide 40 mg PR in Chinese patients with active acromegaly after 32 weeks of treatment.

TRIAL REGISTRATION

Retrospectively registered on ClinicalTrials.gov: NCT02493517 (9 July 2015); prospectively registered on chinadrugtrials.org.cn: CTR20140698 (24 October 2014).

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Acromegaly - Part 2: Therapeutic Issues

Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas. The therapeutic management of acromegaly always requires a personalized strategy. Normal age-matched IGF-I values are the treatment goal. Transsphenoidal surgery by an expert neurosurgeon is the primary treatment modality for most patients, especially if there are neurological complications. In patients with poor clinical conditions or who refuse surgery, primary medical treatment should be offered, firstly with somatostatin analogs (SSAs). In patients who do not reach hormonal targets with first-generation depot SSAs, a second pharmacological option with pasireotide LAR or pegvisomant (alone or combined with SSA) should be offered. Irradiation could be proposed to patients with surgical remnants who would like to be free from long-term medical therapies or those with persistent disease activity or tumor growth despite surgery or medical therapy. Since the therapeutic tools available enable therapeutic targets to be achieved in most cases, the challenge is to focus more on the quality of life.

How to Position Pasireotide LAR Treatment in Acromegaly

CONTEXT

Pasireotide long-acting release (LAR) is a somatostatin multireceptor ligand, and in the current consensus criteria pasireotide LAR is considered the second-line medical treatment for acromegaly. We present in this article our recommendations to define the position of pasireotide LAR in the treatment of acromegaly and provide recommendations for the management of pasireotide-induced hyperglycemia.

EVIDENCE ACQUISITION

Our recommendations are based on our experiences with the pasireotide LAR and pegvisomant (PEGV) combination study and the available basic or clinical articles published in peer-reviewed international journals on pasireotide LAR and acromegaly.

EVIDENCE SYNTHESIS

In accordance with the current consensus criteria, we recommend pasireotide LAR monotherapy as a second-line therapy in young patients who show tumor growth during first-generation somatostatin receptor ligand (SRL) therapy and in patients who show tumor growth during PEGV therapy. In addition, we recommend pasireotide LAR monotherapy in patients with headache not responsive to first-generation SRL therapy and in patients who experience side effects or are intolerant to PEGV monotherapy. In contrast to the current consensus criteria, we recommend considering combination therapy with pasireotide LAR and PEGV as third-line treatment in patients without diabetes at low PEGV dosages (≤80 mg/week) and in patients with tumor growth or symptoms of active acromegaly during first-generation SRL and PEGV combination therapy. With respect to pasireotide-induced hyperglycemia, we recommend a more liberal strategy of blood glucose monitoring during pasireotide treatment.

CONCLUSIONS

In contrast to the current consensus criteria, we recommend a more reluctant use of pasireotide LAR therapy for the treatment of acromegaly.

Medical Treatment with Somatostatin Analogues in Acromegaly: Position Statement

The Korean Endocrine Society (KES) published clinical practice guidelines for the treatment of acromegaly in 2011. Since then, the number of acromegaly cases, publications on studies addressing medical treatment of acromegaly, and demands for improvements in insurance coverage have been dramatically increasing. In 2017, the KES Committee of Health Insurance decided to publish a position statement regarding the use of somatostatin analogues in acromegaly. Accordingly, consensus opinions for the position statement were collected after intensive review of the relevant literature and discussions among experts affiliated with the KES, and the Korean Neuroendocrine Study Group. This position statement includes the characteristics, indications, dose, interval (including extended dose interval in case of lanreotide autogel), switching and preoperative use of somatostatin analogues in medical treatment of acromegaly. The recommended approach is based on the expert opinions in case of insufficient clinical evidence, and where discrepancies among the expert opinions were found, the experts voted to determine the recommended approach.

ACROSTART: A retrospective study of the time to achieve hormonal control with lanreotide Autogel treatment in Spanish patients with acromegaly

OBJECTIVES

The ACROSTART study was intended to determine the time to achieve normalization of GH and IGF-I levels in responding patients with acromegaly administered different dosage regimens of lanreotide Autogel (Somatuline^® Autogel^®).

METHODS

From March 2013 to October 2013, clinical data from 57 patients from 17 Spanish hospitals with active acromegaly treated with lanreotide for ≥4 months who achieved hormonal control (GH levels <2.5ng/ml and/or normalized IGF-I levels in ≥2 measurements) were analyzed. The primary objective was to determine the time from start of lanreotide treatment to hormonal normalization.

RESULTS

Median patient age was 64 years, 21 patients were male, 39 patients had undergone surgery, and 14 patients had received radiotherapy. Median hormonal values at start of lanreotide treatment were: GH, 2.6ng/ml; IGF-I, 1.6×ULN. The most common starting dose of lanreotide was 120mg (29 patients). The main initial regimens were 60mg/4 weeks (n=13), 90mg/4 weeks (n=6), 120mg/4 weeks (n=13), 120mg/6 weeks (n=6), and 120mg/8 weeks (n=9). An initial treatment regimen with a long interval (≥6 weeks) was administered in 25 patients. Mean duration of lanreotide treatment was 68 months (7-205). Median time to achieve hormonal control was 4.9 months. Injections were managed without healthcare assistance in 13 patients. Median number of visits to endocrinologists until hormonal control was achieved was 3. Fifty-one patients were "satisfied"/"very satisfied" with treatment and 49 patients did not miss any dose.

CONCLUSIONS

Real-life treatment with lanreotide Autogel resulted in early hormonal control in responding patients, with high treatment adherence and satisfaction despite disparity in starting doses and dosing intervals.

International Union of Basic and Clinical Pharmacology. CV. Somatostatin Receptors: Structure, Function, Ligands, and New Nomenclature

Somatostatin, also known as somatotropin-release inhibitory factor, is a cyclopeptide that exerts potent inhibitory actions on hormone secretion and neuronal excitability. Its physiologic functions are mediated by five G protein-coupled receptors (GPCRs) called somatostatin receptor (SST)1-5. These five receptors share common structural features and signaling mechanisms but differ in their cellular and subcellular localization and mode of regulation. SST₂ and SST₅ receptors have evolved as primary targets for pharmacological treatment of pituitary adenomas and neuroendocrine tumors. In addition, SST₂ is a prototypical GPCR for the development of peptide-based radiopharmaceuticals for diagnostic and therapeutic interventions. This review article summarizes findings published in the last 25 years on the physiology, pharmacology, and clinical applications related to SSTs. We also discuss potential future developments and propose a new nomenclature.

How are growth hormone and insulin-like growth factor-1 reported as markers for drug effectiveness in clinical acromegaly research? A comprehensive methodologic review

OBJECTIVE

In rare disease research, most randomized prospective clinical trials can only use limited number of patients and are comprised of highly heterogeneous populations. Therefore, it is crucial to report the results in such a manner that it allows for comparison of treatment effectiveness and biochemical control between studies. The aim of this review was to investigate the current methods that are being applied to measure and report growth hormone (GH) and insulin-like growth factor-1 (IGF-1) as markers for drug effectiveness in clinical acromegaly research.

SEARCH STRATEGY

A systematic search of recent prospective and retrospective studies, published between 2012 and 2017, that studied the effects of somatostatin analogues or dopamine agonists in acromegaly patients was performed. The markers of interest were GH, IGF-1, and the suppression of GH after an oral glucose tolerance test (OGTT). Additionally, the use of pharmacokinetic (PK) measurements in these studies was analyzed. The sampling design, cut-off for biochemical control, reported units, and used summary statistics were summarized.

RESULTS

A total of 49 articles were selected out of the 263 screened abstracts. IGF-1 concentrations were measured in all 49 studies, GH in 45 studies, and an OGTT was performed in 11 studies. A wide range of different cut-off values and sampling designs were used to determine biochemical control in acromegaly patients. The summary statistics were reported in various ways, with the percentage of biochemical control most frequently used. Nine studies sampled the PK at one or more time points. Non-compartmental analyses were commonly performed on the available PK data.

CONCLUSIONS

The way GH and IGF-1 are measured and reported in acromegaly research varies considerably. A consensus on how to report study results would enable better comparisons between studies, thereby improving evidence based decision making to optimize treatment in acromegaly.

Biochemical efficacy of long-acting lanreotide depot/Autogel in patients with acromegaly naïve to somatostatin-receptor ligands: analysis of three multicenter clinical trials

PURPOSE

In clinical research involving acromegalic patients naïve to somatostatin-receptor ligands (SRLs), 19 and 31% of those receiving the SRLs octreotide LAR and pasireotide LAR, respectively, achieved GH < 2.5 ng/mL + normalized IGF-1 concentrations. The proportions achieving control appeared higher in the post-surgery compared with the de-novo setting with pasireotide, but more similar with octreotide. Using pooled data from multicenter clinical trials, we examined the biochemical efficacy of lanreotide depot/Autogel in similar settings.

METHODS

Inclusion criteria: Ipsen-sponsored, 48-52-week trials in SRL-naïve acromegalic populations receiving lanreotide depot (60-120 mg); patients were included if de novo (no prior acromegaly treatment) or post-surgery (no medical treatment; radiotherapy allowed unless within previous 3 years). Efficacy endpoints included normalized IGF-1 levels and GH < 2.5 ng/mL + normalized IGF-1 at study end/last value available.

ANALYSES

all patients (analysis #1) and subset with baseline GH > 5 ng/mL (analysis #2).

RESULTS

Three studies were included. Analysis #1: normalized IGF-1 was achieved by 42% (71/171) of patients overall (post-surgery, 46% [21/46]; de-novo, 40% [50/125]); GH < 2.5 ng/mL + normalized IGF-1 was achieved by 35% (59/171) (39% [18/46] and 33% [41/125], respectively). Analysis #2: normalized IGF-1 levels, 39% (46/118) (post-surgery, 40% [10/25]; de-novo, 39% [36/93]); GH < 2.5 ng/mL + normalized IGF-1, 31% (36/118) (28% [7/25] and 31% [29/93], respectively).

CONCLUSION

In these pooled analyses of SRL-naïve patients receiving lanreotide depot, 39-42% achieved IGF-1 control and 31-35% achieved GH and IGF-1 control. Control rates within post-surgery cohorts did not differ markedly from those in corresponding de-novo cohorts.

Novel Somatostatin Receptor Ligands Therapies for Acromegaly

Surgery is considered the treatment of choice in acromegaly, but patients with persistent disease after surgery or in whom surgery cannot be considered require medical therapy. Somatostatin receptor ligands (SRLs) octreotide (OCT), lanreotide, and the more recently approved pasireotide, characterized by a broader receptor ligand binding profile, are considered the mainstay in the medical management of acromegaly. However, in the attempt to offer a more efficacious and better tolerated medical approach, recent research has been aimed to override some limitations related to the use of currently approved drugs and novel SRLs therapies, with potential attractive features, have been proposed. These include both new formulation of older molecules and new molecules. Novel OCT formulations are aimed in particular to improve patients' compliance and to reduce injection discomfort. They include an investigational ready-to-use subcutaneous depot OCT formulation (CAM2029), delivered via prefilled syringes and oral OCT that uses a "transient permeability enhancer" technology, which allows for OCT oral absorption. Another new delivery system is a long-lasting OCT implant (VP-003), which provide stable doses of OCT throughout a period of several months. Finally, a new SRL DG3173 (somatoprim) seems to be more selective for GH secretion, suggesting possible advantages in the presence of hyperglycemia or diabetes. How much these innovations will actually be beneficial to acromegaly patients in real clinical practice remains to be seen.

A multicenter, observational study of lanreotide depot/autogel (LAN) in patients with acromegaly in the United States: 2-year experience from the SODA registry

PURPOSE

This analysis evaluates the 2-year effectiveness and safety of lanreotide depot/autogel (LAN), as well as treatment convenience and acromegaly symptom relief, from the Somatuline^® Depot for Acromegaly (SODA) registry, a post-marketing, open-label, observational, multicenter, United States registry study.

METHODS

Patients with acromegaly treated with LAN were eligible for enrollment. Demographics, LAN dose, extended dosing interval (EDI) (interval of injections ≥42 days), insulin-like growth factor 1 (IGF-1), growth hormone (GH), glycated hemoglobin, adverse events (AEs), injection convenience, and symptom data were collected.

RESULTS

As of September 29, 2014, 241 patients were enrolled in SODA. IGF-1 levels below age- and gender-adjusted upper normal limit (ULN) were achieved in 71.2% at month (M) 12 and 74.4% at M24; GH ≤2.5 µg/L in 83.3% at M12 and 80.0% at M24; GH <1.0 µg/L in 61.7% at M12 and 61.4% at M24. Both IGF-1 < ULN and GH ≤2.5 µg/L were achieved in 65.0% at M12 and 54.8% at M24; both IGF-1 < ULN and GH < 1.0 µg/L were achieved in 51.7 and 42.9% at M12 and M24, respectively. EDI regimen was 5.0% at baseline and 12.0% at M24. At M24, acromegaly symptoms appeared stable or improved. The most common AE was arthralgia (25.7%). Among 106 serious AEs reported by 42 patients, 10 were deemed related to therapy in 9 patients. At M24, 73.1% of patients rated LAN as convenient.

CONCLUSIONS

SODA indicates 2-year biochemical control with majority of patients achieving both IGF-1 < ULN and GH ≤2.5 µg/L. LAN was generally well tolerated with no new or unexpected safety signals reported during the observation period. clinicaltrials.gov Clinical Trial Identifier: NCT00686348.

CLINICAL OUTCOMES AND SELF-REPORTED SYMPTOMS IN PATIENTS WITH ACROMEGALY: AN 8-YEAR FOLLOW-UP OF A LANREOTIDE STUDY

OBJECTIVE

The aim of this study was to evaluate the proportion of patients with acromegaly who remained on long-term lanreotide depot after completion of an open-label multicenter phase III clinical trial (SALSA: A Multi Center Open Label Study to Assess the Ability of Subjects With Acromegaly or Their Partners to Administer Somatuline Autogel), compare baseline and long-term follow-up symptoms scores, and correlate scores with individual longitudinal clinical outcomes.

METHODS

Records of all subjects previously enrolled at the Massachusetts General Hospital site of SALSA were reviewed. Those who remained on lanreotide were interviewed and asked to complete a questionnaire that they had filled out in SALSA in 2007 regarding their current symptomatology and injection side effects, as well as to complete the Acromegaly Quality of Life Questionnaire. Furthermore, clinical, biochemical, and radiographic data related to acromegaly and its comorbidities were tracked throughout follow-up.

RESULTS

Six out of 7 patients chose to remain on lanreotide, and 5 of them continued lanreotide depot through last follow-up, for up to 8 years or in 1 case until death. In all cases, lanreotide remained well tolerated, and insulin-like growth factor-1 levels and pituitary imaging remained well controlled on stable doses. While comorbidities persisted or developed, the self-reported symptom score after up to 8 years of therapy showed a significant decrease in frequency or resolution in symptoms that were reported at baseline.

CONCLUSION

This study shows a significant decrease in frequency or resolution in self-reported symptoms in well-controlled patients receiving long-term lanreotide therapy.

ABBREVIATIONS

AcroQoL = Acromegaly Quality of Life Questionnaire GH = growth hormone GI = gastrointestinal IGF-1 = insulin-like growth factor-1 SALSA = A Multi Center Open Label Study to Assess the Ability of Subjects With Acromegaly or Their Partners to Administer Somatuline Autogel.