Association between Lipid Profile and Glycemic Status in Iraqi patients with Acromegaly Receiving Depot Long-Acting Octreotide

Background: Treatment modalities of acromegaly and disease control impact differently on glucose homeostasis and lipid changes, and consequently on cardiometabolic risk. Aim: To investigate the possible association of lipid profile changes with the glycemic control status in acromegaly patients treated with octreotide LAR. Methods: This cross-sectional study included 52 Iraqi patients with acromegaly treated with octreotide LAR and not using statins. Demographic, anthropometric, and clinical data were collected, as well as the duration of Octreotide LAR administration. The glycemic state was assessed and classified as DM, prediabetes, or normal. Plasma levels of triglycerides, LDL cholesterol, HDL cholesterol, and non-HDL were evaluated using standard methods. Results: Most of the participants presented with low levels of triglycerides, LDL cholesterol, and HDL cholesterol. The lipid profile variables were not significantly correlated with the glycemic control status after treatment with octreotide LAR. Conclusion: Lipid profile parameters were not associated with the different glycemic control status of acromegaly patients treated with octreotide LAR.

Glycemic Status in Acromegaly Patients Receiving Depot Long-Acting Octreotide

Background: Acromegaly is an uncommon, chronic, debilitating condition characterized by hyperinsulinism, insulin resistance, diabetes and prediabetes. One possibility for managing acromegaly's questionable influence on glucose homeostasis is the somatostatin analogues. Aim: To analyze the frequency and risk factors for impaired glucose homeostasis in acromegaly patients treated with depot long-acting octreotide (octreotide LAR), as well as the relationship between risk and treatment duration. Methods: The study included 52 Iraqi adults with acromegaly receiving octreotide LAR. Demographic, anthropometric, and clinical data were collected, as well as the duration of Octreotide LAR administration. Growth hormone, IGF-1, and adenoma size were reported retrospectively from patient data. The glycemic state was assessed and classified as DM, prediabetes, or normal. Results: The prevalence of DM was 39% and prediabetes was 40%, with the exception of being male, which was substantially related with prediabetes. DM and octreotide LAR use had a non-significant correlation. However, octreotide use altered 13% of patients from normal glycemic to prediabetes, with no correlation to treatment duration. Other than hypertension and a family history of diabetes, no other variables were found to be significant. Conclusion: Acromegaly patients have abnormal glucose metabolism, which is associated with prediabetes owing to octreotide LAR medication. Hypertension and family history of diabetes are risk factors.

Population Pharmacokinetic Modelling of the Complex Release Kinetics of Octreotide LAR: Defining Sub-Populations by Cluster Analysis

The aim of the study is to develop a population pharmacokinetic (PPK) model, of Octreotide long acting repeatable (LAR) formulation in healthy volunteers, which describes the highly variable, multiple peak absorption pattern of the pharmacokinetics of the drug, in individual and population levels. An empirical absorption model, coupled with a one-compartment distribution model with linear elimination was found to describe the data well. Absorption was modelled as a weighted sum of a first order and three transit compartment absorption processes, with delays and appropriately constrained model parameters. Identifiability analysis verified that all twelve parameters of the structural model are identifiable. A machine learning method, i.e., cluster analysis, was performed as pre-processing of the PK profiles, to define subpopulations, before PPK modelling. It revealed that 13% of the patients deviated considerably from the typical absorption pattern and allowed better characterization of the observed heterogeneity and variability of the study, while the approach may have wider applicability in building PPK models. The final model was evaluated by goodness of fit plots, Visual Predictive Check plots and bootstrap. The present model is the first to describe the multiple-peak absorption pattern observed after octreotide LAR administration and may be useful to provide insights and validate hypotheses regarding release from PLGA-based formulations.

177Lu-DOTATATE Plus Radiosensitizing Capecitabine Versus Octreotide Long-Acting Release as First-Line Systemic Therapy in Advanced Grade 1 or 2 Gastroenteropancreatic Neuroendocrine Tumors: A Single-Institution Experience

PURPOSE To compare the efficacy and safety of 177Lu-DOTATATE plus radiosensitizing capecitabine and octreotide long-acting release (LAR) as first-line systemic therapy in advanced well-differentiated gastroenteropancreatic neuroendocrine tumors (GEP-NETs). MATERIALS AND METHODS Data of consecutive patients of advanced inoperable or metastatic grade 1 or 2 GEP-NETs treated with first-line 177Lu-DOTATATE plus radiosensitizing capecitabine or octreotide LAR from September 2012 to December 2019 were collected and analyzed for response, toxicity, and survival outcomes. RESULTS Seventy-six patients (median age: 53 years; range 14-81 years) with treatment-naïve advanced grade 1 or 2 GEP-NETs were included. Thirty-six patients received a median cumulative dose of 27.3 GBq of 177Lu-DOTATATE intravenously at 8-12 weeks' intervals along with 1,250 mg/m2 oral capecitabine on days 0-14 of each cycle of 177Lu-DOTATATE, whereas 40 patients were administered 30 mg octreotide LAR intramuscularly every 4 weeks. Using response evaluation criteria in solid tumor 1.1, the objective response rate was 38% in the 177Lu-DOTATATE arm compared with 15% in the octreotide LAR arm ( P = .025), whereas the disease control rates were 88% and 67% in 177Lu-DOTATATE and octreotide LAR arms, respectively ( P = .035). The median durations of progression-free survival in the 177Lu-DOTATATE and octreotide LAR arms were 54 months and 16 months, respectively ( P = .017), whereas the median overall survival was not reached and not significantly different across both the arms. Of the treatment-related adverse events, no major difference was observed in the occurrence of grade 3 or 4 toxicities between the two treatment arms. CONCLUSION First-line systemic 177Lu-DOTATATE plus radiosensitizing capecitabine achieved better radiologic response and longer progression-free survival compared with octreotide LAR in patients with advanced grade 1 or 2 GEP-NETs. Future randomized controlled trials are, however, required to determine the best treatment sequence for the treatment-naïve patients with advanced GEP-NETs.

Randomized blinded study comparing injection site pain from octreotide long-acting-release (LAR) versus lanreotide during the treatment of well differentiated neuroendocrine tumors (WDNETs).

e16204 Background: The somatostatin analogs (SSAs) octreotide LAR and lanreotide are equally acceptable in the NCCN guidelines to treat WDNETs. Average Sales Price for 1 year of lanreotide at 120mg is $106,802 versus $53,471 for 1 year of octreotide LAR 20mg and $80,206 for 1 year of 30mg. Lanreotide is given by “deep subcutaneous injection” while octreotide LAR is given intramuscularly. We conducted a randomized, blinded trial evaluating patient (pt) experience, as measured by injection site pain, with octreotide LAR and lanreotide, during the treatment of advanced, nonfunctional, WDNETs. We also investigated drug preference and financial toxicity in this pt population. Methods: This randomized single-blinded pilot study enrolled 51 pts recommended to begin SSA therapy. Pts received injections q 4 weeks and received 6 injections on study; Arm 1: octreotide LAR for 3 injections then lanreotide for 3 injections; Arm 2: lanreotide for 3 injections then octreotide LAR for 3 injections. Pts were blinded as to which agent they received throughout the study. Self-reported injection site pain scores were obtained after each of the first 3 injections using a 0 to 10 scale (0: “I didn’t feel it”; 10: “worst pain ever”). Primary endpoint was comparison of mean pain scores over the first 3 injections of octreotide LAR (Arm 1) or lanreotide (Arm 2). Secondary endpoints, evaluated with descriptive statistics, included pt-reported preference of octreotide LAR versus lanreotide, and willingness to pay for the preferred therapy, both assessed after 6 months of therapy by questionnaire. Results: 51 pts were enrolled (Arm 1: N = 26, Arm 2: N = 25). All pts were evaluable for the study primary endpoint. All pts received lanreotide at a dose of 120mg monthly; among those pts (49) receiving octreotide LAR, 30 (61%) received 20mg, 18 (37%) received 30mg, 1 (2%) received 10mg. No significant difference was identified in mean pain scores over the first 3 SSA injections; Arm 1: mean 2.4, standard deviation 1.9 versus Arm 2: mean 1.9, standard deviation 1.5 (p = 0.5). 34/51 (67%) pts (15 pts in Arm 1; 19 pts in Arm 2) were evaluated for secondary endpoints and completed post-therapy questionnaires. 7 (47%) in Arm 1 and 8 (42%) in Arm 2 indicated no drug preference at the end of the 6 months. There was a trend towards preference for octreotide LAR versus lanreotide in both arms, with more pts indicating mild or strong preference for octreotide LAR. 7 (50%) and 10 (56%) of pts in Arms 1 and 2, respectively, were unwilling to pay more for their preferred SSA; the rest of the cohort was willing to experience increased financial toxicity to receive their preferred SSA. Conclusions: This randomized, blinded study evaluating pt comfort with SSAs found minimal pain with both agents and no significant differences in pain scores between octreotide LAR versus lanreotide. Clinical trial information: NCT03289741.

Successful Pregnancies in an Acromegalic Woman After Non-Radical Pituitary Adenomectomy for Somatoprolactinoma

Background: Pregnancy is unusual in patients with acromegaly due to somatotropinomas or somatoprolactinomas. Fertility is impaired because of hormonal hypersecretion, pituitary damage by tumor compression or both. Managing somatoprolactinomas and fertility issues are often challenging. Clinical Case: A 20-year woman with primary amenorrhea and headache was diagnosed with hypogonadotrophic hypogonadism secondary to hyperprolactinemia (2500 µg/L, n<23 µg/L). No other abnormalities were found on the pituitary function screening tests. MRI revealed an intra and suprasellar adenoma (2.5x1.8x1.8 cm) with optic chiasm compression. The onset of menses occurred after 11 months under dopaminergic treatment, and tumor size diminished (1.9x1.5x1.5 cm), bringing on optic chiasm decompression. She remained under dopamine agonist treatment for 6 years, when she realized extremities enlargement and height increase by 3 cm. Acromegaly was confirmed by blood levels of IGF-1 (3.37xULN), GH (8 µg/L, n<8 µg/L), and GH nadir (4.3 µg/L, n<1 µg/L) during OGTT. Then, octreotide LAR was added to cabergoline treatment while waiting for elective surgical treatment. She underwent to transsphenoidal endonasal neurosurgical microscopy approach guided by neuronavigation, with the removal of a large portion of tumor. However, it was not possible to extract the part of invasive adenoma close to right carotid artery due to the risk of vascular and intracavernous cranial nerves injury. Immunohistochemistry analysis of the adenoma was positive only for GH cells with low Ki67 index (<1%). Due to the poor biochemical control (unsuppressed post-OGTT GH, IGF-1 1.66xULN and PRL 301 µg/L) and the presence of a small stable tumor residue, treatment with cabergoline and somatostatin analogues was maintained (3-year octreotide LAR, transitioned to lanreotide in an attempt to achieve a better biochemical response). After 14 years of the initial diagnosis and 5 years post-surgery, the patient expressed the desire to get pregnant and all medications in use were suspended. In the following 3 years, she had two uneventful gestation without complications or worsen of acromegaly; she only breastfed for few months after her first pregnancy. The second one was a twin pregnancy. After one year, the MRI revealed no increase of tumor mass (1.0x0.3x1.0 cm), and PRL levels withing normal range, IGF-1 slightly elevated, but GH not suppressed by OGTT. Cabergoline was reintroduced and the biochemical control of acromegaly was achieved. Conclusion: We reported the very unusual spontaneous conception and normal course of pregnancies in a woman with acromegaly, who was submitted to successful transsphenoidal neurosurgical microscopy approach in which large part of the tumor was removed and the normal pituitary tissue was preserved, allowing fertility restoration.

Giant Pituitary Adenoma Presenting With Disinhibition: A Case Report of a 25-Year-Old Male

Background: Giant growth hormone secreting pituitary adenomas (defined by a diameter >4cm) are rare and difficult to treat (1). These typically invade surrounding structures, making surgery challenging or impossible (1). This report highlights a giant mammosomatotrophinoma with an unusual clinical presentation. Clinical Case: A 25-year-old male presented with personality changes, disinhibition and executive dysfunction progressing over a 3 to 4-year period. Further enquiry elicited a history of increasing headaches and significant visual loss, on the background of unilateral childhood visual loss in the contralateral eye. He was noted to have clinical features of acromegaly and complete temporal visual field loss in the left eye. On initial testing plasma IGF-1 was 137 nmol/L (reference interval [RI] 13-43nmol/L), GH >100 ug/L and prolactin 23,900 mIU/L (RI 0-400mIU/L). GH remained >100ug/L at 120 minutes after a 75g oral glucose load. He has hypogonadotropic hypogonadism, however thyrotropic and corticotropic function remained normal. MRI of the brain with contrast revealed an 8.0 x 7.1 x 7.4 cm mass arising from the pituitary fossa, extending into the suprasellar region and displacing both frontal lobes. The mass encased the basilar and right internal carotid arteries. It was deemed inoperable due to its exceptionally large size and encasement of vascular structures. Medical treatment was initiated with cabergoline (3.5mg per week in divided doses) and octreotide LAR, initially 30mg then increased to 60mg 4-weekly. A weaning course of steroids was initiated for oedema of his optic nerve. Within one month of treatment there was improvement of clinical symptoms of headaches, sweating, irritable mood and disinhibition with associated modest biochemical improvement (reduction of IGF-1 to 129 nmol/L and prolactin reduction to 2119 mIU/L). MRI of the brain revealed a reduction in the size of the adenoma to 7.8 x 7.1 x 6.3 cm, with a reduction in the mass effect on the frontal lobes. The patient continues medical management and close clinical monitoring with the aim of ongoing tumour shrinkage to allow reassessment for possible surgical debulking. Conclusion: This unique case of a GH and prolactin co-secreting giant pituitary adenoma posed a therapeutic challenge due to the significant surgical risk, limiting treatment to aggressive medical therapy. The cognitive and behavioral changes experienced due to tumour size and location added to the management complexity. Although early on in the treatment course, there is improvement of symptoms and tumour size on cabergoline and octreotide LAR injections. (1) Iglesias P, Rodríguez Berrocal V, Díez JJ. Giant pituitary adenoma: histological types, clinical features and therapeutic approaches. Endocrine. 2018 Sep;61(3):407-421.