Control of IGF-I levels with titrated dosing of lanreotide Autogel over 48 weeks in patients with acromegaly

Control of acromegaly in more than 90% of patients after 10 years of pegvisomant therapy: an European referral centre real-life experience

PURPOSE

Pegvisomant (PEG) efficaciously controls IGF-I excess in acromegaly and possesses a positive impact on glucose metabolism. Data on very prolonged PEG treatment are still limited, therefore, we investigated the effects of 10-years PEG on disease control, maximal tumour diameter (MTD), and metabolic profile in consecutive patients resistant to somatostatin analogues (SRLs) followed in an European referral centre for acromegaly.

METHODS

Since the 2000s, we collected data on anthropometric, hormonal and metabolic parameters, and MTD of patients receiving PEG. In the current study, we included 45 patients (19 men, 26 women, 46.8 ± 11 years) treated for at least 5 years with PEG mono or combined therapy, analyzing data before, after 5- and 10-years PEG.

RESULTS

After10 years, 91% of patients showed full disease control and in 37% a significant decrease in MTD was found. Diabetes prevalence was slightly increased, whereas HbA1c remained stable over the decade. Transaminases remained stable and no case of cutaneous lipohypertrophy was recorded. A different metabolic impact between mono- or combined therapy was found. Patients in monotherapy showed significantly lower fasting glucose (p = 0.01), fasting insulin (p = 0.008), HbA1c (p = 0.007), HOMA-IR (p = 0.001), and significantly higher ISI₀ (p = 0.002), whereas patients under combined therapy showed significantly lower total (p = 0.03), and LDL cholesterol (p = 0.007). Acromegaly duration before PEG was inversely related to ΔFG (r = - 0.46, p = 0.03) and ΔFI (r = - 0.54, p = 0.05).

CONCLUSIONS

PEG is effective and safe in long term. In patients resistant to SRLs, early beginning of PEG allows a wider gluco-insulinemic improvement.

ACROBAT Edge: Safety and efficacy of switching injected SRLs to oral paltusotine in patients with acromegaly

CONTEXT

Paltusotine is a once-daily, oral, non-peptide small-molecule somatostatin receptor type 2 (SST2) agonist in clinical development for treatment of acromegaly.

OBJECTIVE

To evaluate change in IGF-I levels in patients switched from octreotide LAR or lanreotide depot monotherapy to paltusotine.

DESIGN

Phase 2, open-label, prospective, multicenter, multinational, non-randomized, single-arm exploratory study in which dosage up-titrations were performed in a double-blinded manner.

SETTING

26 global sites.

PARTICIPANTS

Patients with acromegaly switched to paltusotine from injected SRL-based therapy.

INTERVENTIONS

Patients received 13-week treatment with once-daily oral paltusotine (10-40 mg/day).

MAIN OUTCOME MEASURES

Primary endpoint was change from baseline to week 13 in IGF-I for patients who switched from long-acting octreotide or lanreotide monotherapy to paltusotine (Group 1). All patients underwent a 4-week paltusotine washout at end of treatment period (weeks 13-17). IGF-I, GH, patient reported outcome, and safety data were collected.

RESULTS

Forty-seven patients enrolled. In Group 1 (n = 25), IGF-I and GH showed no significant change between SRL baseline and end of paltusotine treatment at week 13 (median change in IGF-I = -0.03×upper limit of normal [ULN], P = 0.6285; GH = -0.05 ng/mL, P = 0.6285). IGF-I and GH rose significantly in the 4 weeks after withdrawing paltusotine (median change in IGF-I = 0.55×ULN, P < 0.0001 [median increase 39%]; GH = 0.72 ng/mL, P < 0.0001 [109.1% increase]). No patients discontinued due to adverse events; no treatment-related serious adverse events were reported.

CONCLUSIONS

These results suggest once daily, oral paltusotine is effective in maintaining IGF-I values in patients with acromegaly who switched from injected SRLs. Paltusotine was well tolerated with a safety profile consistent with other SRLs.

Current and Emerging Medical Therapies in Pituitary Tumors

Pituitary tumors (PT) represent in, the majority of cases, benign tumors for which surgical treatment still remains, except for prolactin-secreting PT, the first-line therapeutic option. Nonetheless, the role played by medical therapies for the management of such tumors, before or after surgery, has evolved considerably, due in part to the recent development of well-tolerated and highly efficient molecules. In this review, our aim was to present a state-of-the-art of the current medical therapies used in the field of PT and the benefits and caveats for each of them, and further specify their positioning in the therapeutic algorithm of each phenotype. Finally, we discuss the future of PT medical therapies, based on the most recent studies published in this field.

External Validity of Somatostatin Analogs Trials in Advanced Neuroendocrine Neoplasms: The GETNE-TRASGU Study

INTRODUCTION

Somatostatin analogs (SSA) prolong progression-free survival (PFS) in patients with well-differentiated gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). However, the eligibility criteria in randomized clinical trials (RCTs) have been restricted, which contrasts with the vast heterogeneity found in NENs.

METHODS

We identified patients with well-differentiated (Ki-67% ≤20%), metastatic GEP-NENs treated in first line with SSA monotherapy from the Spanish R-GETNE registry. The therapeutic effect was evaluated using a Bayesian Cox model. The objective was to compare survival-based outcomes from real-world clinical practice versus RCTs.

RESULTS

The dataset contained 535 patients with a median age of 62 years (range: 26-89). The median Ki-67% was 4 (range: 0-20). The most common primary tumor sites were as follows: midgut, 46%; pancreas, 34%; unknown primary, 10%; and colorectal, 10%. Half of the patients received octreotide LAR (n = 266) and half, lanreotide autogel (n = 269). The median PFS was 28.0 months (95% CI: 22.1-32.0) for octreotide versus 30.1 months (95% CI: 23.1-38.0) for lanreotide. The overall hazard ratio for lanreotide versus octreotide was 0.90 (95% credible interval: 0.71-1.12). The probability of effect sizes >30% with lanreotide versus octreotide was 2 and 6% for midgut and foregut NENs, respectively.

CONCLUSION

Our study evaluated the external validity of RCTs examining SSAs in the real world, as well as the main effect-modifying factors (progression status, symptoms, tumor site, specific metastases, and analytical data). Our results indicate that both octreotide LAR and lanreotide autogel had a similar effect on PFS. Consequently, both represent valid alternatives in patients with well-differentiated, metastatic GEP-NENs.

Discordant GH and IGF-1 Results in Treated Acromegaly: Impact of GH Cutoffs and Mean Values Assessment

CONTEXT

Discordant growth hormone (GH) and insulin-like growth factor-1 (IGF-1) values are frequent in acromegaly.

OBJECTIVE

To evaluate the impact of different GH cutoffs on discordance rate. To investigate whether the mean of consecutive GH measurements impacts discordance rate when matched to the last available IGF-1 value.

DESIGN

Retrospective study.

SETTING

Referral center for pituitary diseases.

PATIENTS

Ninety acromegaly patients with at least 3 consecutive evaluations for GH and IGF-1 using the same assay in the same laboratory (median follow-up 13 years).

INTERVENTIONS

Multimodal treatment of acromegaly.

MAIN OUTCOME MEASURES

Single fasting GH (GHf) and IGF-1 (IGF-1f). Mean of 3 GH measurements (GHm), collected during consecutive routine patients' evaluations.

RESULTS

At last evaluation GHf values were 1.99 ± 2.79 µg/L and age-adjusted IGF-1f was 0.86 ± 0.44 × upper limit of normality (mean ± SD). The discordance rate using GHf was 52.2% (cutoff 1 µg/L) and 35.6% (cutoff 2.5 µg/L) (P = 0.025). "High GH" discordance was more common for GHf <1.0 µg/L, while "high IGF-1" was predominant for GHf <2.5 µg/L (P < 0.0001). Using GHm mitigated the impact of GH cutoffs on discordance (GHm <1.0 µg/L: 43.3%; GHm <2.5 µg/L: 38.9%; P = 0.265). At receiver-operator characteristic curve (ROC) analysis, both GHf and GHm were poor predictors of IGF-1f normalization (area under the curve [AUC] = 0.611 and AUC = 0.645, respectively). The prevalence of disease-related comorbidities did not significantly differ between controlled, discordant, and active disease patients.

DISCUSSION

GH/IGF-1 discordance strongly depends on GH cutoffs. The use of GHm lessen the impact of GH cutoffs. Measurement of fasting GH levels (both GHf and GHm) is a poor predictor of IGF-1f normalization in our cohort.

Multicenter, Observational Study of Lanreotide Autogel for the Treatment of Patients with Acromegaly in Routine Clinical Practice in Germany, Austria and Switzerland

BACKGROUND

Evidence from controlled trials has shown that lanreotide autogel is effective in achieving biochemical and symptom control in patients with acromegaly. However, it is important to better understand the real-world patient population receiving lanreotide autogel treatment.

METHODS

In this non-interventional study the long-term treatment response to lanreotide autogel in adult patients with acromegaly from office-based centers or clinics in Germany, Austria and Switzerland was studied. Assessments included growth hormone and insulin-like growth factor-I levels, symptoms, quality of life, lanreotide plasma levels and tumor somatostatin receptor subtype expression. The primary endpoint was achievement of full biochemical control, defined as growth hormone ≤2.5 µg/L and insulin-like growth factor I normalization at month 12.

RESULTS

76 patients were enrolled from 21 sites. 7/51 (13.7%) patients of the efficacy population had full biochemical control at baseline, 15/33 (45.5%) at month 12 and 10/26 (38.5%) at month 24 of treatment. At 12 months of treatment higher rates of biochemical control were observed in the following subgroups: older patients (>53 years [median]), females, treatment-naïve patients, and patients with a time since diagnosis of longer than 1.4 years (median). No clinically relevant differences in acromegaly symptoms or quality of life scores were observed. Median fasting blood glucose and glycated hemoglobin levels remained unchanged throughout the study. No new safety signals were observed. Overall tolerability of treatment with lanreotide autogel was judged by 80.8% of the enrolled patients at month 12 as 'very good' or 'good'.

CONCLUSION

Treatment with lanreotide autogel in a real-world setting showed long-term effectiveness and good tolerability in patients with acromegaly.

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.

Octreotide-Resistant Acromegaly: Challenges and Solutions

Acromegaly is a rare and severe disease caused by an increased and autonomous secretion of growth hormone (GH), thus resulting in high circulating levels of insulin-like growth factor 1 (IGF-1). Comorbidities and mortality rate are closely related to the disease duration. However, in most cases achieving biochemical control means reducing or even normalizing mortality and restoring normal life expectancy. Current treatment for acromegaly includes neurosurgery, radiotherapy and medical therapy. Transsphenoidal surgery often represents the recommended first-line treatment. First-generation somatostatin receptor ligands (SRLs) are the drug of choice in patients with persistent disease after surgery and are suggested as first-line treatment for those ineligible for surgery. However, only about half of patients treated with octreotide (or lanreotide) achieve biochemical control. Other available drugs approved for clinical use are the second-generation SRL pasireotide, the dopamine agonist cabergoline, and the GH-receptor antagonist pegvisomant. In the present paper, we revised the current literature about the management of acromegaly, aiming to highlight the most relevant and recent therapeutic strategies proposed for patients resistant to first-line medical therapy. Furthermore, we discussed the potential molecular mechanisms involved in the variable response to first-generation SRLs. Due to the availability of different medical therapies, the choice for the most appropriate drug can be currently based also on the peculiar clinical characteristics of each patient.

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).

Surgical-pharmacological interactions in the treatment of acromegaly

INTRODUCTION

Acromegaly requires a multimodal treatment approach that includes surgery by an expert pituitary neurosurgeon, pharmacological treatment with one or more of the available drugs and radiation therapy. These treatment alternatives are not mutually exclusive but rather complement each other when properly indicated in the individual patient. In this review, we summarize and analyze the available data concerning the choice of the surgical approach (microscopy vs. endoscopy) and the interactions between medical treatment with somatostatin analogs and pituitary surgery.

AREAS COVERED

Technical aspects, complications and outcome of transsphenoidal surgery (TSS); Advantages and disadvantages of the microscopic and endoscopic approaches; Safety and efficacy of somatostatin analogs (SSA); Primary pharmacological therapy versus primary TSS; Benefits of the preoperative treatment with SSA; and the effect of surgical tumor debulking in the therapeutic response to SSA.

EXPERT COMMENTARY

Continuing efforts at improving surgical techniques and at generating more efficacious pharmacological therapies for acromegaly are likely to improve the outcome of these patients. However, an integral approach of the patient aimed not only at achieving biochemical criteria of cure but also at treating the individual comorbidities is mandatory to improve the quality of life of these patients and to reduce their mortality rate.

Evaluation of the Efficacy and Safety of Switching to Pasireotide in Patients With Acromegaly Inadequately Controlled With First-Generation Somatostatin Analogs

Introduction: Acromegaly is a rare, serious endocrine disorder characterized by excess growth hormone (GH) secretion by a pituitary adenoma and overproduction of insulin-like growth factor I (IGF-I). Transsphenoidal surgery is the treatment of choice, although many patients require additional interventions. First-generation somatostatin analogs (SSAs) are the current standard of medical therapy; however, not all patients achieve control of GH and IGF-I. Outcomes from a Phase IIIb open-label study of patients with uncontrolled acromegaly on first-generation SSAs switching to pasireotide are reported. Methods: Adults with uncontrolled acromegaly (mean GH [mGH] ≥1 μg/L from a five-point profile over 2 h, and IGF-I >1.3× upper limit of normal [ULN]) despite ≥3 months' treatment with maximal approved doses of long-acting octreotide/lanreotide received open-label long-acting pasireotide 40 mg/28 days. Pasireotide dose could be increased (maximum: 60 mg/28 days) after week 12 if biochemical control was not achieved, or decreased (minimum: 10 mg/28 days) for tolerability. Patients who completed 36 weeks' treatment could continue receiving pasireotide during an extension (weeks 36-72) when concomitant medication for acromegaly was permitted. Primary endpoint was proportion of patients with mGH <1 μg/L and IGF-I <ULN at week 36. Biochemical control was also assessed during the extension. Safety was assessed throughout. Results: One hundred and twenty-three patients were enrolled and received pasireotide; 88 patients continued into the extension. Overall, 18 [14.6% (95% CI: 8.9-22.1)] patients achieved mGH <1 μg/L and IGF-I <ULN at week 36; biochemical control was achieved in 42.9% with screening mGH 1.0-2.5 μg/L and 6.4% with screening mGH >2.5 μg/L. For patients who entered the extension, 14.8% (95% CI: 8.1-23.9), 12.5% (95% CI: 6.4-21.3), 14.8% (95% CI: 8.1-23.9) and 11.4% (95% CI: 5.6-19.9) had mGH <1 μg/L and IGF-I <ULN at weeks 36, 48, 60, and 72, respectively. During the overall study period, most frequent investigator-reported drug-related adverse events were hyperglycemia (41.5%), diabetes mellitus (23.6%), and diarrhea (11.4%). Conclusions: Switching to long-acting pasireotide provided biochemical control in some patients, which was sustained with continued treatment. Long-term safety and tolerability of long-acting pasireotide was consistent with the known safety profile. These data support long-acting pasireotide for some patients with acromegaly who are uncontrolled on first generation SSAs. Clinical Trial Registration: clinicaltrials.gov, identifier: NCT02354508.

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.

Management of hormone-secreting pituitary adenomas

Pituitary adenomas are one of the most common primary central nervous system tumors and have an estimated prevalence of 17%. Approximately half of pituitary adenomas secrete distinct pituitary hormones (most often prolactin, growth hormone, or adrenocorticotropic hormone). While these tumors are histologically benign, they have potent endocrine effects that lead to significant morbidity and shortened lifespan. Because of their pathophysiologic endocrine secretion and anatomic location near critical neural/vascular structures, hormone-secreting pituitary adenomas require defined management paradigms that can include relief of mass effect and biochemical remission. Management of hormone-secreting pituitary adenomas involves a multidisciplinary approach that can incorporate surgical, medical, and/or radiation therapies. Early and effective treatment of hormone-secreting pituitary adenomas can reduce morbidity and mortality. Consequently, understanding clinical features as well as therapeutic options in the context of the specific biological features of each type of hormone-secreting pituitary adenoma is critical for optimal management.

The Growth Hormone Receptor: Mechanism of Receptor Activation, Cell Signaling, and Physiological Aspects

The growth hormone receptor (GHR), although most well known for regulating growth, has many other important biological functions including regulating metabolism and controlling physiological processes related to the hepatobiliary, cardiovascular, renal, gastrointestinal, and reproductive systems. In addition, growth hormone signaling is an important regulator of aging and plays a significant role in cancer development. Growth hormone activates the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway, and recent studies have provided a new understanding of the mechanism of JAK2 activation by growth hormone binding to its receptor. JAK2 activation is required for growth hormone-mediated activation of STAT1, STAT3, and STAT5, and the negative regulation of JAK-STAT signaling comprises an important step in the control of this signaling pathway. The GHR also activates the Src family kinase signaling pathway independent of JAK2. This review covers the molecular mechanisms of GHR activation and signal transduction as well as the physiological consequences of growth hormone signaling.

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.

Remarkable Shrinkage of a Growth Hormone (GH)-secreting Macroadenoma Induced by Somatostatin Analogue Administration: A Case Report and Literature Review

Acromegaly is caused by excessive growth hormone secretion, usually from pituitary adenomas. Somoatostatin analogues are widely used as primary or adjunctive therapy in the management of acromegaly. In this report, we present a case with remarkable shrinkage of a tumor after relatively short-term octreotide long-acting release (LAR) administration. During the 30-month follow-up after starting octreotide LAR, there was no recurrence of acromegaly with remarkable shrinkage of the tumor on pituitary magnetic resonance imaging. A literature review of the predictors for tumor shrinkage after the administration of somatostatin analogues in patients with acromegaly is also discussed in relation to this case.

Effects of long-term combined treatment with somatostatin analogues and pegvisomant on cardiac structure and performance in acromegaly

To date, no data are available on the effects of long-term combined treatment with somatostatin analogues (SA) and pegvisomant (PEG) on cardiovascular complications in acromegaly. The current study aimed at investigating the effects of long-term SA + PEG on cardiac structure and performance. Thirty-six patients (14 M, 22 F, aged 52.3 ± 10.2 years) entered this study. Weight, BMI, systolic (SBP) and diastolic (DBP) blood pressure, IGF-I, fasting glucose (FG), fasting insulin (FI), HOMA-IR, HbA_1c, and lipids were evaluated at baseline (T0), after long-term (median 36 months) SA (T1), after 12 (T12) and 60 (T60) months of SA + PEG, and at last follow-up (LFU, median 78 months). At each time point, all patients underwent echocardiography. At T1, induced a slight but not significant decrease in IGF-I (p = 0.077), whereas FI (p = 0.004), HOMA-IR (p = 0.013), ejection fraction (EF, p = 0.013), early (E) to late (A) ventricular filling velocities (E/A, p = 0.001), and isovolumetric relaxation time (IVRT, p = 0.000) significantly improved. At T12, IGF-I (p = 0.000) significantly reduced compared to T0, and FI (p = 0.001), HOMA-IR (p = 0.000), LVMI (p = 0.000), and E/A (p = 0.006) further improved compared to T1. At T60, FI (p = 0.027), HOMA-IR (p = 0.049), and E/A (p = 0.005) significantly improved as compared to T1. At LFU IGF-I normalized in 83.3 %, FI (p = 0.000), HOMA-IR (p = 0.000), LVMi (p = 0.000), and E/A (p = 0.005) further improved as compared to T1. PEG dose significantly correlated with LVMi at T12 (r = 0.575, p = 0.000) and T60 (r = 0.403, p = 0.037). Long-term PEG addition to SA improves cardiac structure and performance, particularly diastolic dysfunction, in acromegalic patients resistant to SA.

Somatostatin analogs, cabergoline and pegvisomant: comparing the efficacy of medical treatment for acromegaly

Therapies for acromegaly aim at normalizing hormonal excess and controlling tumor growth . Therapeutic approaches are surgery, pharmacotherapy and radiotherapy. Area covered: This review focuses on the role of medical therapy of acromegaly, comparing the efficacy of somatostatin analogues (SSA), dopamine-agonists (DA) and pegvisomant (PEG), the three available drug classes for treating acromegaly. To clarify the difference in response rates reported in the literature for these therapies, we performed a search for original articles published in PubMed. SSA represent the first-line approach to medical treatment. This therapy is effective in controlling acromegaly in about 40% of patients, however there are great differences in the reported hormonal efficacy of SSA in the different series. In patients partially resistant to SSA, cabergoline can be added when hormonal levels are close to normalization, resulting effective in control IGF-I levels in 43% of patients. In patients with higher hormonal levels PEG is indicated, normalizing IGF-I levels in 79.8% and 80.6% of cases when used in monotherapy or in combination with SSA. Pasireotide, the newly developed SSA multi-ligand receptor, represents a new option in SSA resistant patients. Expert commentary: Medical therapy represents an important therapeutic option resulting safe and effective in controlling acromegaly in a high percentage of patients. The best treatment should be individually tailored for each patient, taking into account sex, age, comorbidities, tumor characteristics and hormonal levels.

The ongoing challenge of discrepant growth hormone and insulin-like growth factor I results in the evaluation of treated acromegalic patients: a systematic review and meta-analysis

OBJECTIVE

Growth hormone (GH) and insulin-like growth factor I (IGF-I) are the principal biomarkers used to assess disease activity in acromegaly, and any discrepancy between them renders interpretation of results inconclusive. Purpose of this study was to assess the frequency of this discrepancy and identify parameters that might affect its occurrence.

DESIGN

A systematic review of MEDLINE and Scopus was performed (1987-2013) followed by a meta-analysis to address the frequency of discrepant results between GH and IGF-I levels. Meta-regression and subgroup analyses were performed assessing the effects of the year of publication, the different types of GH testing and GH assays used, as well as the impact of treatment with somatostatin analogues (SSAs) on the occurrence of this discrepancy.

RESULTS

The analysis retrieved 39 eligible studies totalling 7071 patients. The pooled discordance rate between GH and IGF-I was 25·7% (95% CI: 22·3-29·4), and the predominant format was that of elevated IGF-I with normal GH levels (15·3%, 95% CI: 12·5-18·7). No significant correlation between the discordance rate and the year of publication was shown; whereas, the use of ultrasensitive GH assays resulted in higher discordance rates (30·7%, 95% CI: 25·9-35·9 vs 19·8%, 95% CI: 14·1-27·2, P = 0·04) as did treatment with SSAs (32·5%, 95% CI: 27·8-37·4) vs (21·6%, 95% CI: 17·8-25·6, P = 0·001).

CONCLUSIONS

Discrepancy between GH and IGF-I results is encountered in a quarter of treated patients with acromegaly, especially when using ultrasensitive GH assays or in patients receiving SSAs, a fact that the clinician should take into consideration when making clinical decisions.

Interpreting biochemical control response rates with first-generation somatostatin analogues in acromegaly

CONTEXT

The somatostatin analogues octreotide LAR and lanreotide Autogel have been evaluated for the treatment of acromegaly in numerous clinical trials, with considerable heterogeneity in reported biochemical response rates. This review examines and attempts to account for these differences in response rates reported in the literature.

EVIDENCE ACQUISITION

PubMed was searched for English-language studies of a minimum duration of 24 weeks that evaluated ≥10 patients with acromegaly treated with octreotide LAR or lanreotide Autogel from 1990 to March 2015 and reported GH and/or IGF-1 data as the primary objective of the study.

EVIDENCE SYNTHESIS

Of the 190 clinical trials found, 18 octreotide LAR and 15 lanreotide Autogel studies fulfilled the criteria for analysis. It is evident from the protocols of these studies that multiple factors are capable of impacting on reported response rates. Prospective studies reporting an intention-to-treat analysis that evaluated medically naïve patients and used the composite endpoint of both GH and IGF-1 control were associated with lower response rates. The use of non-composite biochemical control endpoints, heterogeneous patient populations, analyses that exclude treatment non-responders, assay variability and prior responsiveness to medical therapy are just a few of the factors identified that likely contribute to higher success rates.

CONCLUSIONS

The wide range of reported response rates with somatostatin analogues may be confusing and could lead to misinterpretation by both the patient and the physician in certain situations. Understanding the factors that potentially drive the variation in response rates should allow clinicians to better gauge treatment expectations in specific patients.

Switching patients with acromegaly from octreotide to pasireotide improves biochemical control: crossover extension to a randomized, double-blind, Phase III study

BACKGROUND

Many patients with acromegaly do not achieve biochemical control with first-generation somatostatin analogues. A large, multicenter, randomized, Phase III core study demonstrated that pasireotide LAR had significantly superior efficacy over octreotide LAR. This analysis explores the efficacy and safety of switching therapeutic arms in inadequately controlled patients during a 12-month crossover extension.

METHODS

Patients with inadequate biochemical control (GH ≥2.5 μg/L and/or IGF-1 > ULN) at end of core study (month 12) were eligible to switch to pasireotide LAR 40 mg/28 days (n = 81) or octreotide LAR 20 mg/28 days (n = 38). One dose escalation to pasireotide LAR 60 mg/28 days or octreotide LAR 30 mg/28 days was permitted, but not mandatory, at month 17 or 20.

RESULTS

Twelve months after crossover, 17.3 % of pasireotide LAR and 0 % of octreotide LAR patients achieved GH <2.5 μg/L and normal IGF-1 (main outcome measure); 27.2 and 5.3 % of pasireotide LAR and octreotide LAR patients achieved normal IGF-1, respectively; 44.4 and 23.7 % of pasireotide LAR and octreotide LAR patients achieved GH <2.5 μg/L, respectively. Mean (±SD) tumor volume further decreased from the end of the core study by 25 % (±25) and 18 % (±28); 54.3 % of pasireotide LAR and 42.3 % of octreotide LAR patients achieved significant (≥20 %) tumor volume reduction during the extension. The safety profile of pasireotide LAR was similar to that of octreotide LAR, with the exception of the frequency and degree of hyperglycemia-related adverse events.

CONCLUSIONS

Pasireotide LAR is a promising treatment option for patients with acromegaly inadequately controlled with the first-generation somatostatin analogue octreotide LAR.

TRIAL REGISTRATION

clinicaltrials.gov, NCT00600886 . Registered 14 January 2008.

Multi-modal management of acromegaly: a value perspective

PURPOSE

The Acromegaly Consensus Group recently released updated guidelines for medical management of acromegaly patients. We subjected these guidelines to a cost analysis.

METHODS

We conducted a cost analysis of the recommendations based on published efficacy rates as well as publicly available cost data. The results were compared to findings from a previously reported comparative effectiveness analysis of acromegaly treatments. Using decision tree software, two models were created based on the Acromegaly Consensus Group's recommendations and the comparative effectiveness analysis. The decision tree for the Consensus Group's recommendations was subjected to multi-way tornado analysis to identify variables that most impacted the value analysis of the decision tree.

RESULTS

The value analysis confirmed the Consensus Group's recommendations of somatostatin analogs as first line therapy for medical management. Our model also demonstrated significant value in using dopamine agonist agents as upfront therapy as well. Sensitivity analysis identified the cost of somatostatin analogs and growth hormone receptor antagonists as having the most significant impact on the cost effectiveness of medical therapies.

CONCLUSION

Our analysis confirmed the value of surgery as first-line therapy for patients with surgically accessible lesions. Surgery provides the greatest value for management of patients with acromegaly. However, in accordance with the Acromegaly Consensus Group's recent recommendations, somatostatin analogs provide the greatest value and should be used as first-line therapy for patients who cannot be managed surgically. At present, the substantial cost is the most significant negative factor in the value of medical therapies for acromegaly.

Safety and efficacy of oral octreotide in acromegaly: results of a multicenter phase III trial

BACKGROUND

A novel oral octreotide formulation was tested for efficacy and safety in a phase III, multicenter, open-label, dose-titration, baseline-controlled study in patients with acromegaly.

METHODS

We enrolled 155 complete or partially controlled patients (IGF-1 <1.3 × upper limit of normal [ULN], and 2-h integrated GH <2.5 ng/mL) receiving injectable somatostatin receptor ligand (SRL) for ≥ 3 months. Subjects were switched to 40 mg/d oral octreotide capsules (OOCs), and the dose escalated to 60 and then up to 80 mg/d to control IGF-1. Subsequent fixed doses were maintained for a 7-month core treatment, followed by a voluntary 6-month extension.

RESULTS

Of 151 evaluable subjects initiating OOCs, 65% maintained response and achieved the primary endpoint of IGF-1 <1.3 × ULN and mean integrated GH <2.5 ng/mL at the end of the core treatment period and 62% at the end of treatment (up to 13 mo). The effect was durable, and 85 % of subjects initially controlled on OOCs maintained this response up to 13 months. When controlled on OOCs, GH levels were reduced compared to baseline, and acromegaly-related symptoms improved. Of 102 subjects completing the core treatment, 86% elected to enroll in the 6-month extension. Twenty-six subjects who were considered treatment failures (IGF-1 ≥ 1.3 × ULN) terminated early, and 23 withdrew for adverse events, consistent with those known for octreotide or disease related.

CONCLUSIONS

OOC, an oral therapeutic peptide, achieves efficacy in controlling IGF-1 and GH after switching from injectable SRLs for up to 13 months, with a safety profile consistent with approved SRLs. OOC appears to be effective and safe as an acromegaly monotherapy.

Pasireotide versus continued treatment with octreotide or lanreotide in patients with inadequately controlled acromegaly (PAOLA): a randomised, phase 3 trial

BACKGROUND

Many patients with acromegaly do not achieve biochemical control despite receiving high doses of the first-generation somatostatin analogues octreotide or lanreotide. In the PAOLA trial, we aimed to assess the efficacy and safety of two different doses of the somatostatin analogue pasireotide long-acting release compared with active control (octreotide or lanreotide) in patients with inadequately controlled acromegaly.

METHODS

In a multicentre, randomised, phase 3 trial, we enrolled eligible patients aged 18 years or older with acromegaly who were inadequately controlled (5-point, 2 h mean growth hormone concentration >2·5 μg/L and insulin-like growth factor 1 [IGF-1] concentration >1·3 times the upper normal limit) and had received 30 mg octreotide long-acting repeatable or 120 mg lanreotide (Somatuline Autogel; Ipsen, UK) as monotherapy for 6 months or longer. We randomly assigned patients in a 1:1:1 ratio with an interactive voice-web response system to receive 40 mg pasireotide long-acting release once every 28 days for 24 weeks, 60 mg pasireotide long-acting release once every 28 days for 24 weeks, or continued treatment with octreotide or lanreotide (active control). Patients were stratified according to previous treatment (octreotide or lanreotide) and growth hormone concentrations at screening (2·5-10 μg/L and >10 μg/L). Patients and study investigators were not masked to study drug assignment but were masked to pasireotide dose allocation. The primary endpoint was number of patients achieving biochemical control, defined as mean growth hormone concentration less than 2·5 μg/L and normalised IGF-1 concentration. Efficacy analyses were based on intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01137682.

FINDINGS

Between Dec 17, 2010, and Aug 6, 2012, 198 patients were enrolled and randomly assigned to pasireotide 40 mg (n=65), pasireotide 60 mg (n=65), or active control (n=68) groups. At 24 weeks, ten (15%) patients in the pasireotide 40 mg group and 13 (20%) patients in the pasireotide 60 mg group achieved biochemical control, compared with no patients in the active control group (absolute difference from control group 15·4%, 95% CI 7·6-26·5, p=0·0006 for pasireotide 40 mg group, 20·0%, 11·1-31·8, p<0·0001 for pasireotide 60 mg group). The most common adverse events were hyperglycaemia (21 [33%] for treatment with 40 mg pasireotide, 19 [31%] with 60 mg pasireotide, and nine [14%] with active control), diabetes (13 [21%], 16 [26%], and five [8%]), and diarrhoea (ten [16%], 12 [19%], and three [5%]); most were grade 1 or 2 in severity. Serious adverse events were reported in six (10%) patients in the pasireotide 40 mg group, two (3%) in the pasireotide 60 mg group, and three (5%) in the active control group.

INTERPRETATION

Pasireotide provides superior efficacy compared with continued treatment with octreotide or lanreotide, and could become the new standard pituitary-directed treatment in patients with acromegaly who are inadequately controlled using first-generation somatostatin analogues.

FUNDING

Novartis Pharma AG. Financial support for medical editorial assistance was provided by Novartis Pharmaceuticals Corporation.

Lanreotide autogel in acromegaly - a decade on

INTRODUCTION

The novel formulation of lanreotide, lanreotide (LAN) autogel (ATG), has been available in Europe since 2001 and USA from 2006 for the treatment of acromegaly. It is one of only two clinically available somatostatin analogs available for use in acromegaly. Data relating to the use of ATG in acromegaly, specifically relating to comparison to octreotide (OCT) LAR and patient acceptability and preference, have been slow to accumulate.

AREAS COVERED

We performed a comprehensive review of the original literature relating to development, pharmacokinetics, acceptability and clinical efficacy of ATG.

EXPERT OPINION

LAN ATG is a novel formulation of LAN consequent on self-assembly of nanotubules in water. Diffusion between molecules within the nanotubules and surrounding tissue fluid in vivo leads to pseudo first-order pharmacokinetics. Efficacy is equivalent to the alternate long-acting somatostatin analog, OCT LAR, normalizing growth hormone and IGF-I levels in around 60 and 50% respectively. Control of tumor growth is observed in over 95% of patients, with 64% seeing a clinically significant reduction in tumor size. ATG is provided in a prefilled syringe for deep subcutaneous injection, allowing self-injection, and may be administered up to 8 weeks greatly improving convenience for the patient. The data strongly support consideration of ATG as the medical therapy of choice for patients with acromegaly.

Tumor shrinkage with lanreotide Autogel 120 mg as primary therapy in acromegaly: results of a prospective multicenter clinical trial

CONTEXT

Methodological shortcomings often compromise investigations into the effects of primary somatostatin-analog treatment on tumor size in acromegaly. There are also limited data for the long-acting lanreotide formulation.

OBJECTIVE

The aim of the study was to better characterize the effects of primary lanreotide Autogel treatment on tumor size in patients with GH-secreting macroadenomas.

DESIGN

PRIMARYS was a 48-week, multicenter, open-label, single-arm study.

SETTING

The study was conducted at specialist endocrine centers.

PATIENTS

Treatment-naïve acromegalic patients with GH-secreting macroadenomas participated in the study.

INTERVENTION

Lanreotide Autogel 120 mg was administered sc every 28 days (without dose titration).

OUTCOME MEASURES

The primary endpoint was the proportion of patients with clinically significant (≥20%) tumor volume reduction (TVR) at week 48/last post-baseline value available using central assessments from three readers. The null hypothesis (H0) for the primary endpoint was that the proportion with TVR was ≤55%. Secondary endpoints included: TVR at other time points, GH and IGF-1, acromegalic symptoms, quality of life (QoL), and safety.

RESULTS

Sixty-four of 90 (71.1%) patients completed the study. Clinically significant TVR at 48 weeks/last post-baseline value available was achieved by 62.9% (95% confidence interval, 52.0, 72.9) of 89 patients in the primary analysis (intention-to-treat population; H0 not rejected) and 71.9-75.3% in sensitivity (n = 89) and secondary analyses (n = 63) (H0 rejected). At 12 weeks, 54.1% had clinically significant TVR. Early and sustained improvements also occurred in GH and IGF-1, acromegalic symptoms, and QoL. No patients withdrew due to gastrointestinal intolerance.

CONCLUSIONS

Primary treatment with lanreotide Autogel, administered at 120 mg (highest available dose) without dose titration, in patients with GH-secreting macroadenomas provides early and sustained reductions in tumor volume, GH and IGF-1, and acromegalic symptoms, and improves QoL.

The role of primary pharmacological therapy in acromegaly

BACKGROUND AND OBJECTIVES

Primary pharmacological therapy may be the only viable treatment option for many patients with acromegaly, especially those presenting with advanced disease with large inoperable tumors. Long-acting somatostatin analogs are currently the first-line treatment of choice in this setting, where they provide biochemical control and reduce tumor size in a significant proportion of patients. We herein present a brief overview of the role of primary pharmacological therapy in the treatment of acromegaly within the context of Latin America and support this with a representative case study.

CASE DESCRIPTION

A 20 year old male presented with clinical and biochemical evidence of acromegaly. The glucose-suppressed growth hormone (GH) was 5.3 μg/L, his insulin-like growth factor-1(IGF-1) was 3.5 times the ULN and serum prolactin greater than 4,000 μg/L. Pituitary MRI revealed a large and invasive mass, extending superiorly into the optic chiasm and laterally into the left cavernous sinus. He was treated with a combination of octreotide and cabergoline with remarkable clinical improvement, normalization of GH and IGF-1 values and striking shrinkage of the adenoma.

CONCLUSION

This case illustrates how effective the pharmacological therapy of acromegaly can be and yet at the same time, raises several important issues such as the need for life-long treatment with costly medications such as the somatostatin analogs. Access to these agents may be limited in regions where resources are restricted and clinicians face challenges in order to make the most efficient use of available options.

Repeat endoscopic transsphenoidal surgery for acromegaly: remission and complications

Reported biochemical remission rates following surgical intervention for acromegaly range from 38 to 83%. In patients not achieving surgical remission, few options remain, mostly limited to medical management and radiation therapy. There is debate over whether or not to offer reoperation to patients in whom surgical remission is not achieved with initial resection. Retrospective chart review was undertaken to determine all patients having acromegaly with persistently elevated GH and/or IGF-1 levels after initial pituitary adenoma resection, and who underwent reoperation using endoscopic endonasal approach at a single institution. Biochemical remission was defined as a postoperative GH level <1 ng/mL and a normal postoperative IGF-1 level in the absence of any medical therapy. In total, 14 patients underwent repeat surgical intervention for acromegaly via endoscopic transsphenoidal approach. Of the 14 patients, 8 (57%) achieved biochemical remission following repeat surgical intervention. Lower preoperative GH levels were associated with greater chance of biochemical remission (P = 0.048). New endocrinopathies were seen in 2 patients (14%), and both were transient diabetes insipidus. Meningitis occurred in 2 patients (14%); both were aseptic meningitis with no sequelae. No mortality was encountered. Repeat surgical intervention for acromegaly via endoscopic transsphenoidal approach appears safe and effective. With no mortality and minimal morbidity, repeat surgical intervention via endoscopic transsphenoidal approach appears a reasonable option for these hard-to-treat patients and should be considered for patients in whom surgical remission is not achieved with initial surgery.

Efficacy, safety, and pharmacokinetics of sustained-release lanreotide (lanreotide Autogel) in Japanese patients with acromegaly or pituitary gigantism

The somatostatin analog lanreotide Autogel has proven to be efficacious for treating acromegaly in international studies and in clinical practices around the world. However, its efficacy in Japanese patients has not been extensively evaluated. We examined the dose-response relationship and long-term efficacy and safety in Japanese patients with acromegaly or pituitary gigantism. In an open-label, parallel-group, dose-response study, 32 patients (29 with acromegaly, 3 with pituitary gigantism) received 5 injections of 60, 90, or 120 mg of lanreotide Autogel over 24 weeks. Four weeks after the first injection, 41% of patients achieved serum GH level of <2.5 ng/mL and insulin-like growth factor-I (IGF-I) level was normalized in 31%. Values at Week 24 were 53% for GH and 44% for IGF-I. Dose-dependent decreases in serum GH and IGF-I levels were observed with dose-related changes in pharmacokinetic parameters. In an open-label, long-term study, 32 patients (30 with acromegaly, 2 with pituitary gigantism) received lanreotide Autogel once every 4 weeks for a total of 13 injections. Dosing was initiated with 90 mg and adjusted according to clinical responses at Weeks 16 and/or 32. At Week 52, 47% of patients had serum GH levels of <2.5 ng/mL and 53% had normalized IGF-I level. In both studies, acromegaly symptoms improved and treatment was generally well tolerated although gastrointestinal symptoms and injection site induration were reported. In conclusion, lanreotide Autogel provided early and sustained control of elevated GH and IGF-I levels, improved acromegaly symptoms, and was well tolerated in Japanese patients with acromegaly or pituitary gigantism.

Management options for persistent postoperative acromegaly

This article presents management options for the patient with acromegaly after noncurative surgery. The current evidence for repeat surgery, adjuvant medical therapy with somatostatin analogues, dopamine agonists, the growth hormone receptor antagonist pegvisomant, combination medical therapy, and radiotherapy in the context of persistent postoperative disease are summarized. The relative advantages and disadvantages of each of these treatment modalities are explored, and a general treatment algorithm that integrates these modalities is proposed.

Comparative effectiveness review of treatment options for pituitary microadenomas in acromegaly

OBJECT

Acromegaly, a syndrome of excess growth hormone (GH) secretion typically caused by a GH-secreting pituitary adenoma, reduces life expectancy by approximately 10 years when left untreated. Treatment of acromegaly involves combinations of one or more discrete therapeutic modalities to achieve biochemical control. Unfortunately, data capable of informing decisions among alternate management strategies are presently lacking.

METHODS

The authors performed a comparative effectiveness research (CER) review integrating efficacy, cost, and quality of life (QOL) analysis for treatment strategies comprising various combinations of surgery, radiotherapy, stereotactic radiosurgery, and pharmacotherapy in patients with acromegaly caused by a pituitary microadenoma. A management decision tree was used to identify 5 treatment strategies, each with up to 4 potential treatment steps. Efficacy was assessed using recent literature reports of biochemical control rates for each modality. Cost estimations were derived from wholesale drug prices and from the Healthcare Cost and Utility Project. Quality of life data were obtained from studies utilizing the Acromegaly Quality of Life Questionnaire.

RESULTS

Individual treatment modalities were analyzed and ranked in each of 3 domains: highest rate of success, lowest cost, and highest QOL, and these scores were combined to facilitate comparison of overall effectiveness of each of the management strategies. These aggregate effectiveness scores were used to compare the 5 strategies from the decision tree, and a novel strategy was also proposed.

CONCLUSIONS

The choice of management strategy must be individualized for each patient with acromegaly. This CER analysis provides a comprehensive framework to inform clinical decisions among alternate management strategies in patients with GH-secreting pituitary microadenomas.

Clinical experience with lanreotide for the treatment of acromegaly

Acromegaly is a rare disease, characterized in adults by its distinctive appearance of facial dysmorphism and swollen fingers. It is caused by an overproduction of growth hormone (GH) in more than 99% of patients and in nearly all cases is due to a pituitary adenoma. If surgical resection of the adenoma is not effective, medical treatment is usually the next treatment option. The most commonly used medications are the somatostatin analogues octreotide and lanreotide. Lanreotide is a synthetic somatostatin analogue and is available as slow-release microparticle (every 7-14 days) and prolonged-release liquid (autogel, every 28-56 days) formulations. Lanreotide autogel is a supersaturated aqueous formulation for deep subcutaneous injection and is sold in a ready-to-use prefilled syringe. This ease of use allows self or partner administration at home. This article reviews the use of lanreotide in the treatment of acromegaly and its advantages and disadvantages compared with other somatostatin analogues.

Lanreotide depot deep subcutaneous injection: a new method of delivery and its associated benefits

Acromegaly is a rare disease characterized by excessive growth hormone secretion, usually from a pituitary tumor. Treatment options include surgery, medical therapy, and in some cases, radiation therapy. Current medical therapy consists of treatment with somatostatin analog medications or a growth hormone receptor antagonist. There are two somatostatin analogs currently in use, octreotide and lanreotide. Both are supplied in long-acting formulations and are of comparable biochemical efficacy. Lanreotide is supplied in a prefilled syringe and is injected into deep subcutaneous tissue. Studies have been conducted to assess the efficacy of self- or partner administration, and have demonstrated that injection of lanreotide can be accomplished reliably and safely outside a physician's office. For patients who have achieved biochemical control with lanreotide, the FDA has recently approved an extended dosing interval. Selected patients may be able to receive the medication less frequently with injections of 120 mg administered every 6 or 8 weeks. This review focuses on the use of lanreotide in the treatment of acromegaly, the safety and efficacy of the drug, and the benefits afforded to patients because of unique aspects of the delivery of lanreotide.

Safety review: dose optimization of somatostatin analogs in patients with acromegaly and neuroendocrine tumors

INTRODUCTION

Patients with either acromegaly or neuroendocrine tumors (NET) can be treated with somatostatin analogs to relieve symptoms and improve disease control. However, there is an absence of large clinical trials specifically designed to document the safety when increases in somatostatin analog dosing are needed in patients who do not achieve their treatment goals. To fully explore and communicate any potential risks, we conducted a literature review and present a summary of the studies documenting the safety and tolerability of dose optimization with somatostatin analogs in patients with acromegaly and NET.

METHODS

A literature search was undertaken to find clinical studies specifically reporting the effects of dose titration using the depot formulations of the somatostatin analogs, octreotide long-acting repeatable (LAR) or lanreotide, in patients with acromegaly and NET.

RESULTS

Publications that described the treatment and management of patients with acromegaly and NET were reviewed. The rationale for dose optimization, including high-dose treatment in patients who are inadequately controlled on conventional doses and the safety and tolerability of somatostatin analogs, is discussed.

CONCLUSION

A review of published clinical studies demonstrates that dose optimization provides additional biochemical control in patients with acromegaly and NET who are inadequately controlled with conventional starting doses of octreotide LAR and lanreotide ATG. The benefits of dose optimization include improved efficacy without a significant change in the recorded adverse events and the tolerability of the treatment. Therefore, patient response to treatment should be routinely monitored and their somatostatin analog dose increased or decreased thereafter according to their individual response.

Six-month preoperative octreotide treatment in unselected, de novo patients with acromegaly: effect on biochemistry, tumour volume, and postoperative cure

OBJECTIVE

Treatment with somatostatin analogues is the primary medical treatment of acromegaly. Controversies still exist whether acute octreotide effect predicts long-term biochemical effects, tumour regression or surgical cure. This prospective study investigates effect of 6-month treatment with octreotide long-acting repeatable (LAR) on insulin-like growth factor-1 (IGF-1) and growth hormone (GH) levels, pituitary function, tumour regression and postoperative cure in de novo acromegalic patients.

DESIGN AND METHODS

After a baseline evaluation including fasting hormone levels, MRI scan and an acute 50 μg octreotide test, 32 patients were treated with octreotide LAR 20 mg every 28th day for 6 months before surgery. Treatment effects on IGF-1 and GH levels, serum hormone levels and tumour volume were monitored. Surgical cure was evaluated 3 months postoperatively.

RESULTS

Mean tumour volume reduction was 35%, in one-third of the patients more than 50%, while approximately one-third achieved biochemical remission evaluated by normalized IGF-1 levels. The GH reduction following an acute octreotide test was 81 ± 19% and associated with long-term GH reduction (r = 0·78, P < 0·0005). However, neither acute (r = 0·29, P = 0·12) nor the long-term octreotide effect (r = 0·11, P = 0·58) on GH levels was associated with tumour volume reduction and did not predict subsequent surgical cure.

CONCLUSION

Six months of long-acting octreotide using a fixed dose, 1/3 of the patients came in biochemical remission, while 2/3 had significant tumour reduction. Moreover, an acute effect of octreotide seemed to be a prerequisite for long-term effect.

Clinical efficacy and safety results for dose escalation of somatostatin receptor ligands in patients with acromegaly: a literature review

Acromegaly is a rare disease with a multifaceted clinical presentation. In 90-95% of patients with acromegaly, the disease is caused by a growth hormone (GH)-secreting pituitary adenoma with elevated GH levels that ultimately induce excessive hepatic secretion of insulin-like growth factor-1 (IGF-1). Somatostatin receptor ligands (SRLs) are considered the standard medical choice for the treatment of acromegaly, and normalization of GH and IGF-1 is attainable with effective therapy. This review aims to summarize the literature relative to SRL dose escalation therapy in patients with acromegaly. A United States National Library of Medicine PubMed search of SRL's was conducted using the following search terms: ((((LAR) OR ATG) OR octreotide) OR lanreotide Autogel) AND acromegaly. Related articles in non peer-reviewed journals were excluded. The rationale and benefits of SRL dose optimization therapy were investigated with emphasis on describing the clinical recognition, treatment, and management of patients with acromegaly. We found that dose escalation could provide additional biochemical control of acromegaly in patients who are inadequately controlled with conventional starting doses of octreotide LAR and lanreotide Autogel(®). Furthermore, patients should routinely have their GH and IGF-1 levels closely monitored and their SRL dose increased or decreased thereafter according to individual response.

Resistance to somatostatin analogs in acromegaly

Somatostatin analogs (SA) are widely used in acromegaly, either as first-line or adjuvant treatment after surgery. First-line treatment with these drugs is generally used in the patients with macroadenomas or in those with clinical conditions so severe as to prevent unsafe reactions during anesthesia. Generally, the response to SA takes into account both control of GH and IGF-I excess, with consequent improvement of clinical symptoms directly related to GH and IGF-I excess, and tumor shrinkage. This latter effect is more prominent in the patients treated first-line and bearing large macroadenomas, but it is also observed in patients with microadenomas, even with little clinical implication. Predictors of response are patients' gender, age, initial GH and IGF-I levels, and tumor mass, as well as adequate expression of somatostatin receptor types 2 and 5, those with the highest affinity for octreotide and lanreotide. Only sporadic cases of somatostatin receptor gene mutation or impaired signaling pathways have been described in GH-secreting tumors so far. The response to SA also depends on treatment duration and dosage of the drug used, so that a definition of resistance based on short-term treatments using low doses of long-acting SA is limited. Current data suggest that response to these drugs is better analyzed taking together biochemical and tumoral effects because only the absence of both responses might be considered as a poor response or resistance. This latter evidence seems to occur in 25% of treated patients after 12 months of currently available long-acting SA.

Conventional and novel biomarkers of treatment outcome in patients with acromegaly: discordant results after somatostatin analog treatment compared with surgery

CONTEXT

Control of disease activity in acromegaly is critical, but the biochemical definitions remain controversial.

OBJECTIVE

To compare traditional and novel biomarkers and health status in patients with acromegaly treated with either surgery alone or somatostatin analog (SA).

DESIGN AND METHODS

Sixty-three patients in long-term remission based on normalized total IGF1 levels after surgery alone (n=36) or SA (n=27) were studied in a cross-sectional manner. The groups were comparable at diagnosis regarding demographic and biochemical variables. Each subject underwent 3 h of serum sampling including a 2-h oral glucose tolerance test (OGTT). Health status was measured by two questionnaires: EuroQoL and Acrostudy (Patient-assessed-Acromegaly symptom questionnaire (PASQ)).

RESULTS

Total and bioactive IGF1 (μg/l) levels were similar (total: 185 ± 10 (SA) versus 171 ± 8 (surgery) (P=0.28); bioactive: 1.9 ± 0.2 vs 1.9 ± 0.1 (P=0.70)). Suppression of total and free GH (μg/l) during OGTT was blunted in the SA group (total GH(nadir): 0.59 ± 0.08 (SA) versus 0.34 ± 0.06 (surgery) (P=0.01); free GH(nadir): 0.43 ± 0.06 vs 0.19 ± 0.04 (P<0.01)). The insulin response to OGTT was delayed, and the 2-h glucose level was elevated during SA treatment (P=0.02). Disease-specific health status was better in patients after surgery (P=0.02).

CONCLUSIONS

i) Despite similar and normalized IGF1 levels, SA treatment compared with surgery alone was associated with less suppressed GH levels and less symptom relief; ii) this discordance may be due to specific suppression of hepatic IGF1 production by SA; iii) we suggest that biochemical assessment during SA treatment should include both GH and IGF1.

Rapid and sustained reduction of serum growth hormone and insulin-like growth factor-1 in patients with acromegaly receiving lanreotide Autogel therapy: a randomized, placebo-controlled, multicenter study with a 52 week open extension

The study was designed to evaluate the long-term efficacy and safety of the 28-day prolonged-release Autogel formulation of the somatostatin analogue lanreotide (Lan-Autogel) in unselected patients with acromegaly. The study comprised four phases: washout; a double-blind comparison with placebo, at a single randomized dose (60, 90 or 120 mg) of Lan-Autogel; a single-blind, fixed-dose phase for four injections (placebo group was re-allocated to active treatment); and eight injections with doses tailored according to biochemical response. Serum samples were assessed for growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels, at weeks 4, 13, 14, 15, 16, 32 and 52. 108 patients were enrolled and 99 completed 52 weeks' treatment. Four weeks after the first injection, serum GH levels decreased by >50% from baseline in 63% of patients receiving Lan-Autogel compared with 0% receiving placebo (P < 0.001). After four injections, 72% of patients had a >50% reduction in GH levels; 49% patients achieved GH levels < or = 2.5 ng/ml; 54% had normalized IGF-1; and 38% achieved the combined criterion of GH level < or = 2.5 ng/ml and normalized IGF-1. The corresponding proportions by week 52 were 82, 54, 59 and 43%, respectively. In patients not requiring dose escalation to 120 mg, 85% achieved biochemical control (combined criterion). Treatment was well tolerated by all patients. In conclusion, Lan-Autogel was effective in controlling GH and IGF-1 hypersecretion in patients with acromegaly and showed a rapid onset of action.

Cost-effectiveness of lanreotide Autogel in treatment algorithms of acromegaly

The introduction of effective pharmacological treatments has changed the management of acromegaly. However, chronic, life-long treatment with somatostatin analogues and/or growth hormone receptor antagonists is very expensive. We estimated the costs of treatment algorithms to control acromegaly from a Dutch perspective. We used the following assumptions: after the diagnosis of acromegaly there is a mean remaining lifespan of approximately 33 years; the success rates of surgery and somatostatin analogues in controlling the disease are approximately 60%; and the lifelong costs of different algorithms to control acromegaly in 100 patients ranged from 43 million euros (primary surgery and secondary somatostatin analogues) to 57 million euros (primary somatostatin analogues and secondary surgery) and even reached 95 million euros (medical treatment only). In algorithms that include trans-sphenoidal surgery, the lifetime treatment costs are almost 46-59% cheaper per 100 patients than in algorithms with medical treatment but without trans-sphenoidal surgery. Algorithms with primary surgery and secondary somatostatin analogs are 30% cheaper per 100 patients than algorithms with primary somatostatin analogues and secondary surgery. Per 100 patients, algorithms including lanreotide Autogel are 14-34% more expensive than algorithms including octreotide long-acting release. These life-long costs should be taken into consideration when making choices between treatment algorithms.

Significant tumour shrinkage after 12 months of lanreotide Autogel-120 mg treatment given first-line in acromegaly

OBJECTIVE

To evaluate GH and IGF-I control and tumour shrinkage in newly diagnosed patients with acromegaly treated first-line with lanreotide-Autogel (ATG) 120 mg. Design Open, prospective.

PATIENTS

Twenty-six patients (17 women, aged 31-70 years): eight enclosed and 12 extrasellar (eight invasive) macroadenomas and six microadenomas (one invasive). ATG 120 mg initially given every 4 weeks for 12 weeks; then intervals between injections increased to every 6 or 8 weeks if GH levels were <or= 2.5 or < 1 microg/l (equal to 6.5 and 2.6 mU/l), respectively.

RESULTS

Final dosage was ATG 120 mg every 4 weeks in nine patients (34.6%), every 6 weeks in eight patients (30.8%) and every 8 weeks in the remaining nine patients (34.6%). After 12 months, both GH and IGF-I were controlled in 14 patients (53.8%). The mean tumour volume decreased from 1405 +/- 1827 mm(3) at study entry to 960 +/- 1381 mm(3) after 6 months, and 799 +/- 1161 mm(3) after 12 months (P < 0.0001). Overall tumour shrinkage was 35.8 +/- 28.1% after 6 months and 48.4 +/- 27.6% after 12 months. After 12 months, 20 patients (76.9%) achieved > 25% tumour shrinkage: 12 of 14 with controlled disease (85.7%) and 8 of 12 with noncontrolled disease (66.7%; P = 0.49). Hyperhydrosis, paresthesiae and arthralgias significantly reduced after treatment. No patient withdrew from the study because of adverse events.

CONCLUSION

ATG 120 mg in newly diagnosed patients with acromegaly controls GH and IGF-I secretion in 53.8% and induces >or= 25% tumour shrinkage in 76.9% during a 12-month period. The treatment was associated with improvement of clinical symptoms and with a good safety profile.

Recent advances in the treatment of acromegaly

PURPOSE OF REVIEW

Description of recent outcomes and approaches to the treatment of patients with de-novo and recurrent acromegaly.

RECENT FINDINGS

Radiosurgery for acromegaly results in a higher likelihood of remission and an earlier time to remission than does conventional radiotherapy. Somatostatin analogs results in control of acromegaly and one half of patients. Combining treatment with pegvisomant and somatostatin analogs results in overall improved quality of life.

SUMMARY

Existing treatments offer patients and their treating physicians opportunities to restore life expectancy to normal and reverse many of the symptoms and signs of acromegaly.

Lanreotide for the treatment of acromegaly

Lanreotide is an eight-amino acid peptide, which is an analog of the native somatostatin peptide, physiological inhibitor of growth hormone (GH). The drug shows high binding affinity for somatostatin receptors, SSTR2 and SSTR5, which is the primary mechanism considered to be responsible for decreasing GH secretion and GH cell proliferation in acromegaly. Two different formulations of lanreotide are currently available: lanreotide slow release, which requires intramuscular injection every 7-14 days, and lanreotide autogel, which requires deep subcutaneous injection every 4-8 weeks. Several studies have been published to date on the use of lanreotide in acromegaly. Antisecretory efficacy has been reported in 35%-70% of cases; this huge variability is probably explained by different indications (eg, primary or adjunctive postsurgical treatment), or the fact that some studies were based on patients known to be responders to somatostatin analogs. As a primary treatment, antisecretory efficacy was very similar, confirming the possibility of lanreotide as an option in cases of unsuccessful surgery, contraindication, or surgery refusal. Lanreotide also has antitumoral effects as it induces a decrease in tumor volume of [Symbol: see text]25% in 30%-70% of patients. This could be beneficial before transsphenoidal surgery, as a pretreatment, to decrease tumor volume and ease surgery; however, to date, advantages in terms of final remission or uncured status remain a matter of debate. Side effects are rare; the most frequent being gastrointestinal discomfort and increased risk of gallstone formation, and glucose metabolism modifications. Comparison with the other somatostatin analog, octreotide, tends to show identical levels of efficacy between both drugs. Lanreotide thus seems to be an effective treatment in acromegaly. To date, however, lanreotide is still considered as only suspending GH secretion, thus requiring prolonged and costly treatment.