Growth hormone replacement in adults with cured acromegaly: Efficacy and safety.

Between 2% and 60% of patients with cured acromegaly may eventually develop growth hormone deficiency. In adults, growth hormone deficiency is associated with abnormal body composition, decreased exercise capacity and quality of life, dyslipidemia, insulin resistance and increased cardiovascular risk. Similar to patients with other sellar lesions, the diagnosis of growth hormone deficiency in adults with cured acromegaly generally requires stimulation testing, with the exception of patients with very low serum insulin-like growth factor I levels and multiple additional pituitary hormone deficiencies. In adults with cured acromegaly, growth hormone replacement may have beneficial effects on body adiposity, muscle endurance, serum lipids and quality of life. Growth hormone replacement is generally well-tolerated. Arthralgias, edema, carpal tunnel syndrome and hyperglycemia may occur in patients with cured acromegaly, as is true of patients with growth hormone deficiency of other etiologies. However, there is evidence of increased cardiovascular risk in some studies of growth hormone replacement in adults with cured acromegaly. More studies are needed to fully establish the beneficial effects and elucidate the risks of growth hormone replacement in adults with cured acromegaly. Until then, growth hormone replacement can be considered in these patients on a case-by-case basis.

Comparing treatment with daily and long-acting growth hormone formulations in adults with growth hormone deficiency: Challenging issues, benefits, and risks.

Daily administration of growth hormone (GH) treatment has been in clinical use for treatment for GH deficiency (GHD) in adults for more than 30 years. Numerous studies have demonstrated evidence that GH treatment improves body composition, cardiovascular risk factors and quality of life with few side effects. Less frequent GH injections are hypothesized to improve adherence and several long-acting GH (LAGH) formulations have been developed and a few have been approved and marketed. Different pharmacological modifications have been applied and the pharmacokinetics and pharmacodynamics of LAGH are different to each other and to those of daily injections and require different dosing and monitoring specific for each LAGH. Studies have shown improved adherence with LAGH, and short-term efficacy and side effects are comparable between daily GH injections and LAGHs. Long-term treatment with daily GH injections is effective and safe, while long-term studies for LAGHs are awaited. In this review challenges, benefits, and risks of treatment with daily and long-acting GH preparations will be compared.

Safety and effectiveness of Omnitrope® (somatropin) in PATRO Children: a multi-center, post-marketing surveillance study comparison of US and international cohort data.

There are known geographical differences in growth hormone deficiency (GHD) patient populations and treatment practices. Here, we present a comparison of safety and effectiveness data from patients treated with recombinant human growth hormone (rhGH) in the USA versus other countries. PAtients TReated with Omnitrope® (PATRO) Children is an international, non-interventional study with Omnitrope® (somatropin, Sandoz Inc.). All visits and assessments are carried out according to routine clinical practice, and doses of Omnitrope® are given according to country-specific prescribing information. By September 2018, 294 patients had been enrolled in the USA (53% rhGH-naïve) and 6206 patients had been enrolled across 13 other countries (international group; 86% rhGH-naïve). The most common indication in both groups was GHD. Overall, 194 US patients (66%) and 2977 international patients (48%) experienced adverse events (AEs; 886 and 11,716 events, respectively), most of which were of mild or moderate intensity. The AEs were suspected to be treatment-related in five US patients (1.7%) and 452 international patients (7.3%). All reported neoplasms were benign, non-serious, and considered unrelated to rhGH therapy. No cases of diabetes mellitus or hyperglycemia were reported. In rhGH-naïve GHD patients, after 3 years of rhGH therapy, the improvement in mean height SD score from baseline was + 1.25 and + 1.35 in US and international patients, respectively. CONCLUSION: Omnitrope® treatment appears to be well tolerated and effective in US patients and those from other countries. Across the pediatric indications included, there was no evidence of an increased risk of developing uncommon or unexpected AEs with rhGH. TRIAL REGISTRATION: NA. WHAT IS KNOWN: • Continued monitoring of patients treated with recombinant human growth hormone (rhGH) is important, particularly in terms of diabetogenic potential and the risk of malignancies. • The PAtients TReated with Omnitrope® (PATRO) Children study is a long-term, post-marketing surveillance program for the rhGH Omnitrope®. WHAT IS NEW: • Omnitrope® is well tolerated and effective in US patients, and those from other countries. • Across all indications included, there were no unexpected adverse events and there was no evidence of an increased risk of developing malignancies or diabetes.

Pathophysiology of radiation-induced growth hormone deficiency: efficacy and safety of GH replacement.

Radiation-induced growth hormone deficiency (GHD) is primarily due to hypothalamic damage. GH secretion by the pituitary may be affected either secondary to some degree of quantitative deprivation of hypothalamic input or, if the radiation dose is high enough, by direct pituitary damage. As a consequence, the neurosecretory profile of GH secretion in an irradiated patient remains pulsatile and qualitatively intact. The frequency of pulse generation is unaffected, but the amplitude of the GH pulses is markedly reduced. Over the last 25 years, the final heights achieved by children receiving GH replacement for radiation-induced GHD have improved; these improvements are attributable to refinements in GH dosing schedules, increased use of GnRH analogues for radiation-induced precocious puberty, and a reduced time interval between completion of irradiation and initiation of GH therapy. When retested at the completion of growth, 80-90% of these teenagers are likely to prove severely GH deficient and, therefore, will potentially benefit from GH replacement in adult life. Such long-term GH treatment in patients treated previously for a brain tumor means that critical and continuous surveillance must be devoted to the risk of tumor recurrence and the possibility of second neoplasms.

Chemotherapeutic treatment of extensive optic pathway tumors in infants.

Two infants, ages 14 and 4 months, with extensive optic pathway tumors were treated with intensive chemotherapy called MADDOC: nitrogen mustard, doxorubicin, cis-platinum, dacarbazine, vincristine, and cyclophosphamide. The first child had hydrocephalus with an enhancing mass at the hypothalamus which followed the optic radiation to include the lateral geniculate body and medial temporal lobe. A v-p shunt was placed, and biopsy revealed a Grade II astrocytoma. One month later, the child developed malignant ascites. Intensive induction chemotherapy was then begun with cis-platinum 100 mg/m2 and cyclophosphamide 3 g/m2 for two initial cycles. The ascites resolved within one week, and chemotherapy was continued for 10 courses of the 6-drug MADDOC regimen. CT scans showed a gradual shrinkage of the tumor mass by approximately 70%. The enhancing areas continued to decrease in size through 20 months after completing MADDOC. The child has not received radiation and is well 4 years 7 months post diagnosis. The second infant had massive enlargement of the right optic nerve with an enhancing chiasmatic mass extending into the suprasellar space, hypothalamus, and brain stem. This infant was not biopsied; she also received induction MADDOC chemotherapy for 12 cycles. CT scans showed a definite decrease in the chiasmatic mass by the fifth cycle, with continued reduction by approximately 40% after 10 months. Twenty-three months from diagnosis there was asymptomatic evidence of tumor growth. The child is being treated with carboplatinum and remains ophthalmologically and radiographically stable 43 months from diagnosis.

Transgenic mice with inducible dwarfism.

The pituitary gland, composed of the anterior, intermediate and posterior lobe, represents a principal regulatory interface through which the central nervous system controls body physiology. The ontogeny of the growth hormone (GH) and prolactin (Prl) producing cells of the anterior pituitary has been analysed in transgenic mice, using the thymidine kinase obliteration system (TKO). Cells expressing the herpes virus 1 thymidine kinase (HSV1-TK) gene acquire pharmacological sensitivity to synthetic nucleosides such as FIAU (1-(2-deoxy-2-fluoro-beta-delta-arabinofuranosyl)-5-iodouracil), whose metabolites kill dividing cells. Consequently we created transgenic mice carrying the HSV1-TK gene under the control of either the rat growth hormone or the rat prolactin promoter. If transgenic mice expressing HSV1-TK in somatotropes (GH-producing cells) are treated with FIAU, they develop as dwarfs. The anterior pituitary in these animals is nearly devoid of both somatotropes and lactotropes (Prl-producing cells). By contrast, transgenic mice expressing HSV1-TK in the lactotropes, treated with FIAU, have anatomically and histologically normal pituitaries. Because toxicity depends on cell division, we conclude that Prl expression and lactotrope differentiation are post-mitotic events. These results indicate that both somatotropes and lactotropes derive from a common GH-expressing stem-somatotrope. Unexpectedly, the stemsomatotrope is still present in the adult animal and is capable of repopulating the pituitaries of treated animals with mature GH and Prl producing cells.