An open-label dose-escalation study of once-daily and twice-daily pasireotide in healthy volunteers: safety, tolerability, and effects on glucose, insulin, and glucagon levels

Pasireotide is a multireceptor-targeted somatostatin analogue that has high affinity for 4 of the 5 somatostatin receptor subtypes (sst1,2,3 and sst5) and has therapeutic potential in conditions with tumors of neuroendocrine origin, such as Cushing disease, acromegaly, and neuroendocrine tumors. This phase 1, open-label, dose-escalation study assessed the overall safety and tolerability of once-daily and twice-daily pasireotide and its effects on glucose, insulin, and glucagon levels in healthy volunteers. Eleven cohorts (n = 6 for each) received subcutaneous pasireotide 150, 300, 600, 900, 1200, or 1500 μg once daily, or 150, 300, 450, 600, or 750 μg twice daily, for 8 days. Pasireotide was generally well tolerated at all doses; adverse events were predominantly mild-to-moderate gastrointestinal disorders. All participants experienced fasting and postprandial plasma glucose elevations after all doses of pasireotide; increases in blood glucose level seemed to be dose dependent. Hyperglycemia was associated with a marked suppression of insulin secretion and a mild inhibition of glucagon secretion. In conclusion, pasireotide showed good overall tolerability at doses up to 1500 μg once daily and 750 μg twice daily for 8 days. Both fasting and postprandial hyperglycemia occurred after all doses of pasireotide, which was related to the suppression of insulin secretion.

Clinical applications of somatostatin analogs for growth hormone-secreting pituitary adenomas

Excessive growth hormone (GH) is usually secreted by GH-secreting pituitary adenomas and causes gigantism in juveniles or acromegaly in adults. The clinical complications involving cardiovascular, respiratory, and metabolic systems lead to elevated morbidity in acromegaly. Control of serum GH and insulin-like growth factor (IGF) 1 hypersecretion by surgery or pharmacotherapy can decrease morbidity. Current pharmacotherapy includes somatostatin analogs (SAs) and GH receptor antagonist; the former consists of lanreotide Autogel (ATG) and octreotide long-acting release (LAR), and the latter refers to pegvisomant. As primary medical therapy, lanreotide ATG and octreotide LAR can be supplied in a long-lasting formulation to achieve biochemical control of GH and IGF-1 by subcutaneous injection every 4-6 weeks. Lanreotide ATG and octreotide LAR provide an effective medical treatment, whether as a primary or secondary therapy, for the treatment of GH-secreting pituitary adenoma; however, to maximize benefits with the least cost, several points should be emphasized before the application of SAs. A comprehensive assessment, especially of the observation of clinical predictors and preselection of SA treatment, should be completed in advance. A treatment process lasting at least 3 months should be implemented to achieve a long-term stable blood concentration. More satisfactory surgical outcomes for noninvasive macroadenomas treated with presurgical SA may be achieved, although controversy of such adjuvant therapy exists. Combination of SA and pegvisomant or cabergoline shows advantages in some specific cases. Thus, an individual treatment program should be established for each patient under a full evaluation of the risks and benefits.

A first-in-man study to evaluate the safety, tolerability, and pharmacokinetics of pasireotide (SOM230), a multireceptor-targeted somatostatin analog, in healthy volunteers

Pasireotide (SOM230) is a multireceptor-targeted somatostatin analog with high binding affinity for four of the five somatostatin receptor subtypes (sst_1,2,3 and sst₅), and potential clinical activity in several neuroendocrine and oncologic conditions, including acromegaly, Cushing’s disease, and neuroendocrine tumors (NET). This manuscript reports the first-in-man dose-escalation study of pasireotide, evaluating its safety, tolerability, and pharmacokinetics (PK) in healthy male volunteers. A single dose of pasireotide 1–1200 μg was administered subcutaneously in four to eight subjects per dose level, with two additional subjects per cohort administered placebo. PK and safety evaluations were carried out over 7 days post-dose. Growth hormone (GH) suppression was evaluated using a GH-releasing hormone stimulation test on Day –1 and Day 1 at 3–5 hours post-injection. Seventy-two subjects completed the study. Pasireotide was well tolerated with no serious adverse events observed at any dose. Transient elevations in blood glucose levels were observed 2–6 hours after administration of pasireotide at doses between 200 μg and 1200 μg, but this resolved without intervention by 23 hours post-dosing. The maximum tolerable dose was not established within the tested range. Pasireotide demonstrated a favorable PK profile with fast absorption (t_max: 0.25–0.5 hours), low clearance (CL/F: 8–13 L/hour), long effective elimination half-life (mean t_½,β: 7–11 hours), and a proportional dose-exposure relationship. GH suppression of 79%–96% was observed at single pasireotide doses between 200 μg and 1200 μg. In conclusion, pasireotide demonstrated favorable safety, tolerability, and PK profiles, as well as promising activity in suppressing the release of GH. The efficacy and safety of pasireotide is currently being evaluated in patients with acromegaly, Cushing’s disease, NET, and various non-neuroendocrine disorders.

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.

Somatostatin analogues for treatment of polycystic liver disease

PURPOSE OF REVIEW

The present review summarizes the existing knowledge on polycystic liver disease (PCLD) and highlights the progress made in medical treatment for this condition in the past year.

RECENT FINDINGS

PCLD is associated with autosomal dominant polycystic kidney disease (ADPKD) and autosomal dominant PCLD. Signaling pathways of adenosine 3',5'-cyclic monophosphate (cAMP) and mammalian target of rapamycin (mTOR) are aberrantly regulated in polycystic livers and promote hepatic cystogenesis. Somatostatin analogues reduce intracellular cAMP, and this might prevent fluid accumulation in hepatic cysts. Several clinical trials published over the last year now show that somatostatin analogues when given for 6-12 months in patients with ADPKD and PCLD decrease total liver volume, attenuate polycystic kidney volume, and improve perception of health. In two recent studies mTOR inhibitors failed to halt the progression of ADPKD. It is still too early to recommend to start somatostatin analogues in PCLD and definitive answers should come from future clinical trials.

SUMMARY

Somatostatin analogues are promising new medical drug options in the treatment of PCLD. However, more needs to be elucidated with regard to molecular mechanisms in hepatic cystogenesis, the uncertainty who will respond to therapy and long-term outcomes.

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.

Lanreotide reduces the volume of polycystic liver: a randomized, double-blind, placebo-controlled trial

BACKGROUND & AIMS

Therapy for polycystic liver is invasive, expensive, and has disappointing long-term results. Treatment with somatostatin analogues slowed kidney growth in patients with polycystic kidney disease (PKD) and reduced liver and kidney volume in a PKD rodent model. We evaluated the effects of lanreotide, a somatostatin analogue, in patients with polycystic liver because of autosomal-dominant (AD) PKD or autosomal-dominant polycystic liver disease (PCLD).

METHODS

We performed a randomized, double-blind, placebo-controlled trial in 2 tertiary referral centers. Patients with polycystic liver (n = 54) were randomly assigned to groups given lanreotide (120 mg) or placebo, administered every 28 days for 24 weeks. The primary end point was the difference in total liver volume, measured by computerized tomography at weeks 0 and 24. Analyses were performed on an intention-to-treat basis.

RESULTS

Baseline characteristics were comparable for both groups, except that more patients with ADPKD were assigned to the placebo group (P = .03). The mean liver volume decreased 2.9%, from 4606 mL (95% confidence interval (CI): 547-8665) to 4471 mL (95% CI: 542-8401 mL), in patients given lanreotide. In the placebo group, the mean liver volume increased 1.6%, from 4689 mL (95% CI: 613-8765 mL) to 4895 mL (95% CI: 739-9053 mL) (P < .01). Post hoc stratification for patients with ADPKD or PCLD revealed similar changes in liver volume, with statistically significant differences in patients given lanreotide (P < .01 for both diseases).

CONCLUSIONS

In patients with polycystic liver, 6 months of treatment with lanreotide reduces liver volume.

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.

Spotlight on lanreotide Autogel in acromegaly

Lanreotide Autogel (ATG) [Somatuline Depot]The use of trade names is for product identification purposes only and does not imply endorsement. is a novel, long-acting preparation of the somatostatin analog lanreotide acetate that acts via somatostatin receptors to reduce both growth hormone (GH) and insulin-like growth factor-I (IGF-I) levels. It is indicated for the management of acromegaly and, relative to most other licensed agents, it has a favorable pharmacokinetic profile that permits administration once every 28-42 days. Subcutaneous lanreotide ATG was an effective and generally well tolerated treatment in patients with acromegaly in well designed trials and extension studies of up to 4 years' duration. It was shown to be no less effective than intramuscular lanreotide long-acting (LA) microparticle treatment in these studies, with more limited data showing that lanreotide ATG therapy was as effective as intramuscular octreotide long-acting repeating (octreotide LAR) treatment. While both of these latter agents offer the advantage of treatment once every 28 days, lanreotide ATG also has the advantage of being available in a convenient pre-filled syringe and is given subcutaneously rather than intramuscularly like other somatostatin analogs. Thus it provides a valuable first-line option for the management of patients with acromegaly.