Methylpentylaminopropylidenebisphosphonate (BM 21.0955): a new potent and safe bisphosphonate for the treatment of cancer-associated hypercalcemia

Bisphosphonates have been shown to be effective in lowering serum calcium levels in patients with cancer-associated hypercalcemia. 1-Hydroxy-3-(methylpentylamino)propylidenebisphosphonate (BM 21.0955) was developed as a third generation bisphosphonate and has been recently proven effective in animals and in patients with Paget's disease or tumor osteolysis. Thirty-six patients with cancer-associated hypercalcemia were treated with increasing doses (0.2-2.0 mg) of BM 21.0955 by single i.v. infusion over 4 h in a phase I trial. Six patients were rejected from analysis due to concomitant treatment with other bisphosphonates or chemotherapy. After rehydration and infusion of BM 21.0955 the mean serum calcium levels fell significantly (P < 0.001), from 3.29 +/- 0.49 mmol/l to 3.04 +/- 0.44 mmol/l until day 2 and normalized on day 6 (2.66 +/- 0.33 mmol/l). Serum calcium was reduced in all patients and normalized in 16. No symptomatic hypocalcemia occurred. Mean serum creatinine decreased significantly (P < 0.01), from 1.25 +/- 0.58 mg/dl (day 0) to 1.05 +/- 0.37 mg/dl (day 6). The mean urinary calcium/creatinine concentration fell significantly (P < 0.001), from 1.90 +/- 1.16 mM/mM (day 0) to 0.37 +/- 0.34 mM/mM/l (day 6). There were no subjective drug-related side effects during or after the infusion. Thirteen patients had elevations of morning body temperature above 38 degrees C. This was due to confirmed infections in five patients and possibly drug- or tumor-related in the other eight. We conclude from these preliminary results that a single infusion of BM 21.0955 is an effective and safe way to treat cancer-associated hypercalcemia.

Growth hormone and bone metabolism

GH is a potent anabolic hormone for bone and calcium metabolism, not only via direct effects but also mediated through other systems. The individual effects on bone metabolism are summarized in Table 1. Some of the signs (low BMD and low serum osteocalcin) and symptoms (increased prevalence of vertebral fractures) seen in patients with GHD may be due to the lack of GH itself, others may be due to secondary hormone deficiencies or changes in body composition induced by GHD. GH treatment can reverse changes of calcium metabolism. Whether it is able to increase bone mass still needs to be determined in larger and longer studies. Some patients with established osteoporosis and vertebral fractures seem to suffer from GHD. Treatment of osteoporosis with GH has not previously been successful, but studies with more patients over several years to investigate the effects of GH treatment on vertebral fracture rates are lacking. As GH seems to reverse some signs of old age, such as muscle weakness and reduced exercise capacity, it is possible to speculate that GH could prevent the occurrence of hip fractures in elderly people.

Outcome of bone mineral density in anorexia nervosa patients 11.7 years after first admission

Osteopenia is a typical finding in patients suffering from anorexia nervosa. Unfortunately, available longitudinal studies are limited by a relatively short follow-up period. Therefore cross-sectional long-term followup studies may help to determine both the outcome of this bone lesion and variables that influence its subsequent development. Of an initial 66 consecutive patients with anorexia nervosa, 51 (77.3%) could be further evaluated. After an average of 11.7 years following first admission, cross-sectional measurements of lumbar and proximal radial bone mineral density (BMD) were performed. The ability to predict BMD using variables obtained from anamnestic and clinical data was then determined by multiple-regression analysis. The BMD of both radial and lumbar bone in anorexic patients with poor disease outcome (as defined by the Morgan-Russell general outcome categories) deviated by -2.18 and -1.73 SD (Z score), respectively. In patients with a good disease outcome lumbar BMD was significantly less reduced compared with radial BMD (-0.26 versus -0.68 SD). Variables reflecting estrogen deficiency and nutritional status in the course of the disease, that is, relative estrogen exposure (for lumbar BMD) and years of anorexia nervosa (for radial BMD), allowed the best prediction of BMD. A marked reduction in cortical and trabecular BMD in anorexic patients with poor disease outcome suggests a higher risk of fractures in these patients. Furthermore, the finding of a persistently reduced cortical and a slightly reduced trabecular BMD, even in patients with good disease outcome, suggests that a recovery of trabecular BMD might be possible, at least in part. Recovery of cortical bone, if possible at all, seems to proceed more slowly.

Levels of parathyroid hormone-related protein (PTHrP) in hypercalcemia of malignancy are not lowered by treatment with the bisphosphonate BM 21.0955

Parathyroid hormone-related protein (PTHrP) is a major cause of hypercalcemia in malignancy and serum levels are elevated in many patients suffering from this syndrome. In 10 patients with hypercalcemia of malignancy the levels of the midregional fragment of PTHrP in serum were determined by radioimmunoassay over 7 days during a calcium-lowering treatment with a single dose of the bisphosphonate BM 21.0955. PTHrP concentrations remained unchanged 6 days after administration of the drug as compared with pretherapeutic values, thus apparently excluding an effect of either the drug itself or the rapid fall in serum calcium on the release of PTHrP by the tumors or on its clearance from the circulation. In the patients with elevated midregional PTHrP levels (n = 6), the calcium-lowering effect of the drug was significantly less pronounced than in patients with normal PTHrP (n = 4) (mean serum calcium of 2.89 vs. 2.51 mmol/l at day 6), despite similar pretherapeutic concentrations. Of the six patients with elevated PTHrP, five were still hypercalcemic, whereas in the group with normal PTHrP one out of four patients remained hypercalcemic. In conclusion, PTHrP levels in hypercalcemia of malignancy remained unchanged after calcium-lowering therapy with bisphosphonates. High serum PTHrP levels were, however, predictive of a lesser effectiveness of the drug in lowering serum calcium.

Serum levels of intact parathyroid hormone and alkaline phosphatase correlate with cortical and trabecular bone loss in primary hyperparathyroidism

We examined the relationship between bone loss and several biochemical indices in 38 patients with primary hyperparathyroidism. Bone mineral density was reduced by 12 +/- 4.0% in the lumbar spine, 18 +/- 4.2% at the distal radius and 21 +/- 2.8% at the proximal radius (mean +/- SEM). There were significant negative correlations between the serum concentrations of intact parathyroid hormone (PTH) and the Z-scores of the bone mineral content at the proximal and distal radius. In the lumbar spine, bone mineral density was greater in patients with mildly elevated PTH and less in patients whose PTH levels exceeded 8.6 pmol/l. We also observed a strong association between increased levels of serum alkaline phosphatase and low bone mineral Z-scores. Our data thus indicate that cortical and, with the exception of mild primary hyperparathyroidism, trabecular bone loss is proportional to the concentration of circulating PTH and the severity of PTH-induced bone turnover. For the individual patient, however, the usefulness of intact PTH and alkaline phosphatase measurements for assessing bone loss associated with primary hyperparathyroidism seems to be only limited.

Reduced bone mineral density and low parathyroid hormone levels in patients with the adult form of hypophosphatasia

Hypophosphatasia is a heritable metabolic bone disease with characteristically reduced levels of alkaline phosphatase (ALP) in the blood, liver, kidney and bone. ALP levels are normal in the intestine and placenta. About 300 patients have been reported so far in the literature. Three kindreds with 52 known subjects are described here, whereby 12 subjects could be examined osteologically. Four subjects were patients and had clinical signs of the disease: spontaneous fractures of the metatarsals or femora and low ALP serum levels ranging between 8 and 23 U/l (normal range 40-170 U/l). Four other members without fractures had reduced ALP levels; they might be carriers of the disease and develop symptoms later in life. The four remaining subjects had normal ALP levels and no signs of the disease. Serum levels of intact parathyroid hormone (iPTH) were found to be in the lower normal range and serum calcium levels in the upper normal range. There was a significant (P less than 0.05) negative correlation between iPTH and serum calcium levels (r = -0.78). Urinary calcium excretion was increased in 3 subjects with fractures. 25-OH-D3 levels were increased in 6 of 8 subjects without any treatment. The bone mineral density (BMD) was measured using dual X-ray absorptiometry of the lumbar spine, representing mainly trabecular bone, and single-photon absorptiometry of the forearm, measuring mainly cortical bone. Z-scores of the spinal bone mass ranged between 0.38 and -1.95 SD; Z-scores of the forearm bone mass ranged between 0.53 and -2.47 SD with the lowest values in patients with fractures.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term excess of endogenous calcitonin in patients with medullary thyroid carcinoma does not affect bone mineral density

In a cross-sectional study of 39 patients with medullary thyroid carcinoma (MTC), we have investigated the effects of long-term calcitonin excess on bone mineral density. Bone mineral density was measured by dual X-ray absorptiometry at the lumbar spine between the second and fourth vertebra and by single photon absorptiometry at the distal forearm. The mean observation time of each patient between diagnosis of tumour and measurement of bone mineral density was 62.4 months (range 1-158 months). The mean calcitonin serum level was 14.4 micrograms/l at the time of measurement of bone mineral density. All patients were substituted with 150-200 micrograms L-thyroxine daily. At both sites, the mean bone mineral densities of all patients with MTC were not significantly different from controls. Patients with normal calcitonin levels (below 0.2 micrograms/l) after treatment had a normal bone mineral density of the spine but significantly (P less than 0.05) reduced bone mineral density values of the forearm. This was due to the decreased body surface areas of patients in this subgroup. Patients with multiple endocrine neoplasia type IIa had significantly higher bone mineral densities. Other bone-influencing factors, such as postoperative hypoparathyroidism, calcium intake, diarrhoea, menopause, tumour stage, previous anti-tumour treatment, or thyroxine substitution dose, did not affect bone mineral density. We thus conclude that long-term excess of endogenous calcitonin in patients with MTC has no positive effect on bone mineral density.

Bone mass of spine and forearm in osteoporosis and in German normals: influences of sex, age and anthropometric parameters

We measured forearm bone mineral density (BMD) using single photon absorptiometry (SPA) and bone mineral content (BMC) and BMD of lumbar spine by dual photon absorptiometry (DPA). The population consisted of 463 bone healthy subjects, 346 females and 117 males aged 20-85 years. Any underlying bone disease or other diseases known to affect bone mass were excluded by physical examination, thoracic and lumbar radiographs and laboratory screening. Patients with osteoarthritis of lumbar spine were excluded as well as patients taking drugs known to affect bone mass. All bone mass values declined with age. Body height also declined with age by 1.2 cm and 1.8 cm per 10 years (-0.7% and -1%) in females and males respectively. Main effects of age, body height, -surface, -weight and -mass index on bone mass were calculated using multiple regression models. In males and females lumbar BMC measured in gHA depended primarily on body height and secondarily on age. Spinal BMD as measured in g cm-2 was primarily dependent on age and then on height. In females forearm BMD depended primarily on age and then on body surface, in males on body surface only. Using receiver operating characteristic (ROC) analysis the ROC area increased from 0.81-0.85 (n.s.) including body height into spinal BMD values leading to a higher sensitivity of measurements of spinal bone mass in recognizing 58 patients with spinal postmenopausal osteoporosis. Including body surface into forearm BMD measurements ROC area increased from 0.66-0.69 (P = 0.055).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of endogenous and exogenous calcitonin on inflammation-mediated osteopenia in the rat

Inflammation-mediated osteopenia (IMO) in the rat is characterized by loss of bone mass within 3 weeks after induction of nonspecific inflammation (s.c. talcum injections) in growing rats. Histologically, this shows as marked inhibition of osteoblasts 3 days after the initiation of IMO. The role of calcitonin (CT) was investigated in the present study. A reversible increase of serum CT levels was found after intraperitoneal calcium challenge in rats on day 4 after induction of IMO, which was thought to be a result from calcium efflux from bone. No difference in stimulated serum CT levels between the rats with and without IMO was seen on any other day during 4 weeks after initiation of IMO. Bone loss after IMO was more pronounced in normocalcemic and euthyroid rats with deficiency of endogenous CT (thyroidectomy with parathyroid gland reimplanted) (-12.9%) compared with sham operated controls with IMO (-3.25%). Daily subcutaneous injections of 100 mIU salmon CT in rats with and without IMO did not prevent the development of bone loss. This might have been due to the growing state of rats of this age group. Our results support the hypothesis that endogenous CT physiologically has a bone protective role. They furthermore are consistent with the view that endogenous CT itself is not pathogenetically involved in the development of osteoporosis.

[Increased prevalence of osteoporosis and arteriosclerosis in conventionally substituted anterior pituitary insufficiency: need for additional growth hormone substitution?]

In a retrospective study of 632 patients with pituitary disease we diagnosed pituitary insufficiency without hypersecretion of any pituitary hormone in 122 patients. Patients were substituted with sex hormones (76%), hydrocortisone (74%) and/or L-thyroxine (77%). 76% had additional growth hormone deficiency, as shown by an increase of growth hormone of less than 5 ng/ml after i.v. administration of L-arginine. In 17% of all patients the diagnosis of osteoporosis was proven or suspected radiologically. 57% had low bone mass of lumbar spine (dualphotonabsorptiometry) and 73% had low bone mass of the proximal forearm (singlephotonabsorptiometry). BMD values of pituitary insufficient patients were in the same range as those of patients with established osteoporosis. More than half of all patients (53%) complained of tiredness, exhaustion and muscle weakness. 40% suffered from adipositas. 77% had hyperlipidemia (68% hypertriglyceridemia and 42% hypercholesterinemia), 18% had hypertension. 14% of the patients had arteriosclerotic events in their history (myocardial infarction or stroke). These figures are higher than incidences shown in the German PROCAM-study. These data show an increased prevalence of osteoporosis and vascular diseases. This is in contrast to the general opinion, that patients with pituitary insufficiency are adequately treated by substitution with adrenal, thyroid and sex hormones. Whether other factors such as the additional growth hormone deficiency are responsible for these diseases has to be examined in prospective studies.

Superior local tolerability of human versus salmon calcitonin preparations in young healthy volunteers

Possible local and systemic adverse effects following administration of salmon (sCT) and human (hCT) calcitonin (CT) have been evaluated in a double-blind, within-subject, comparative trial in 30 young, healthy volunteers. Each subject received 0.25 and 0.5 mg hCT and 100 IU sCT s.c.. Adverse effects and hypocalcaemia were recorded 1, 3 and 6 h after each injection. Significantly fewer local adverse reactions were observed after hCT (20 or 33%) than after sCT (80%), possibly due to the different vehicles employed (mannitol solution and acetic acid). The most frequent systemic adverse effects were gastrointestinal (nausea, vomiting), which occurred in 80% after 1 h, independently of the CT--preparation used. Hypocalcaemic changes were generally small and lasted longer after sCT. It is concluded that the hCT preparations were better tolerated locally than sCT in young, healthy volunteers, and that there were no differences in the systemic side effects or hypocalcaemic activity.

Increased incidence of euthyroid and hyperthyroid goiters independently of thyrotropin in patients with acromegaly

The incidence of palpable goiters, the thyroid functional state and thyroid radioisotope uptake was analyzed retrospectively in 80 patients with acromegaly and 80 patients with prolactinomas. 71% of all patients with acromegaly had an enlargement of the thyroid (goiter); 49% of them had diffuse and 39% nodular goiters. The incidence of goiters in patients with prolactinomas from the same iodine deficient geographic region was only 35% (82% diffuse and 18% nodular). 17.5% of acromegalic patients underwent thyroid surgery before diagnosis of growth hormone excess. 17.5% of acromegalic patients with goiters had autonomous areas in their thyroids and 5% were clearly hyperthyroid. Goiters developed slightly more often in females (74%) than in males (67%). The mean preoperative growth hormone level was higher in acromegalic patients with goiter. The incidence of goiters was positively correlated with the documented time of elevated growth hormone concentration in serum. Two patients with exaggerated response of thyrotropin (TSH) (delta TSH greater than 20 mU/l) to the application of thyrotropin-releasing hormone (TRH) had no goiters. On the other hand most patients (61%) with goiters had a low TSH-response to TRH (delta TSH less than 10 mU/l) representing in part occult autonomy of thyroid function. No patient with prolactinoma has had previous thyroid surgery nor thyroid autonomy. One patient with prolactinoma suffered from Graves' disease and none of the acromegalic patients had this disease. We finally conclude that the elevation of growth hormone leads to increased incidence of euthyroid and hyperthyroid (autonomous) goiters independently of the influence of TSH.

[Terguride in hyperprolactinemia--experiences with 5 patients]

Hyperprolactinemia can successfully be treated by dopaminagonists such as bromocriptin or lisuride. About 10% of patients complain about side effects like orthostatic hypotension, nausea or vomiting, which may lead to discontinuation of treatment. We therefore conducted a study using terguride--a new dopaminagonist--in 5 patients with hyperprolactinemia and intolerable side effects under conventional treatment. Terguride is the transdihydroderivative of lisuride (Dopergin). We treated 5 patients, 2 men with macroprolactinoma and 3 women with microprolactinoma with terguride. The mean duration of treatment was 15.6 months (7-37 months). Patients were treated with up to 5 mg terguride daily. All 5 patients had a marked initial decrease of elevated prolactin levels 8 h after administration of 0.25 mg terguride orally. Three patients became normoprolactinemic after sufficient increase of the dose of terguride, 2 female patients with a microprolactinoma got eumenorrhoeic thereafter. The treatment with terguride was tolerated without side effects by all patients. There were no significant changes of the examined parameters of clinical chemistry nor the other pituitary hormones. Results of cranial computertomography did not change in 4 patients, one patient had tumor progression. Tergurid as a dopaminagonist is an effective inhibitor of prolactin with little side effects and thus a useful drug in the treatment of hyperprolactinemia.

Bone mass reduction after estrogen deprivation by long-acting gonadotropin-releasing hormone agonists and its relation to pretreatment serum concentrations of 1,25-dihydroxyvitamin D3

Estrogen deficiency results in bone mass reduction of largely varying extent in postmenopausal females, indicating that additional mechanisms influence the response of bone. They are by no ways identified in either the animal experiment or under clinical conditions. In search for factors, conditioning the response of bone to estrogen deficiency, we have conducted a study in females under treatment with the GnRH agonist decapeptyl (D-Trp6-LHRH). This drug blocks ovarian function and was administered for treatment of endometriosis or uterine leiomyoma. We determined spinal (dual photon absorptiometry) and forearm (single photon absorptiometry) bone mineral density before and 3 and 6 months after the onset of therapy and measured biochemical parameters of bone metabolism. Our results showed an increase in bone turnover after initiation of estrogen deficiency, as indicated by the elevation of alkaline phosphatase and osteocalcin. This resulted in a secondary decrease in serum intact PTH and 1,25-dihydroxy-vitamin D3. Furthermore, we found a positive correlation between pretreatment values of serum 1,25-dihydroxyvitamin D3 as well as its decrease and the reduction in bone mass during GnRH agonist treatment. This demonstrates that the patients' metabolic conditions predict their response to estrogen deficiency.

A study of complaints and their relation to vertebral destruction in patients with osteoporosis

Patients with spinal osteoporosis suffer from vertebral deformation, loss of height and back pain, as well as from functional limitations and alterations of mood. So far little is known about the extent of these clinical symptoms at all and whether they are related in a predictable manner to the fractures or damages of bone structure. In the present study we investigated the relation between vertebral deformation and clinical symptoms in 70 patients with osteoporosis. Clinical data like pain, functional limitations and parameters of mood were examined by a standardized questionnaire. The numbers of vertebral fractures were determined, and the vertebral destruction was quantified using the Spine Deformity Index (SDI). The symptoms and functional limitations were graded and correlated to the SDI and the number of fractures. Our results underline a relation between the extent of vertebral deformation and the reduction in quality of life by pain, functional limitations and alterations of mood. This relationship was absent or less evident, if the number of fractures was taken into account. Besides the difficulties concerning the grading and quantification of clinical symptoms and outcome of disease, our study revealed that there is a causal relation between the extent of vertebral destruction measured by the SDI and the extent of these clinical parameters.

[Cardiomyopathy in hypocalcemia]

A 48-year-old woman developed a hypocalcaemic cardiomyopathy, the hypocalcaemia being due to hypoparathyroidism after three previous thyroid operations for goitre with tracheal compression. She had signs of severe cardiac failure, but no tetany. She was put on calcium and vitamin D3 medication which raised calcium concentration. The cardiac status improved, as did the radiological and echocardiographic findings, without the patient having received any diuretics, digitalis or afterload lowering drugs.

A newly developed spine deformity index (SDI) to quantitate vertebral crush fractures in patients with osteoporosis

The available methods to quantitate vertebral deformity in osteoporotics are not satisfactory in comparing follow-up measurements in patients. This paper describes a newly developed 'spine deformity index' (SDI) which allows the quantitation of the extent of vertebral fractures. It is based on the observation that, in 110 normal persons, the heights of all vertebral bodies were related to each other in a predictable and constant manner. This relation was independent of the body height of the individual and was preserved despite growth acceleration during the last century. Since in all but one of our osteoporotic patients the 4th thoracic vertebra was unfractured we were able to compare the actual size of their fractured vertebrae to the calculated presumable original heights. The differences between presumable original and actual heights gave a measure of the extent of vertebral compression and allowed to define an index representing the sum of all spinal fractures in osteoporotics. The method was applied retrospectively to X-rays of 39 patients with idiopathic osteoporosis. Thirty-two of them were treated orally with 80 mg sodium fluoride, 1,000 mg calcium and 3000 IE vitamin D daily. Treatment resulted in a reduction of the progression of vertebral deformity. Seven inadequately treated patients had more pronounced progression of vertebral deformity.

Inflammation-mediated osteopenia (IMO) during acute inflammation in rats is due to a transient inhibition of bone formation

Local inflammation was induced in rats through the subcutaneous injection of magnesium silicate. Trabecular bone volume of the tibia decreased progressively during a 3 week observation period following the inflammatory stimulus. The trabecular bone surface covered with osteoblasts was strikingly reduced during the first week but had normalized by the end of the third week. Calcification rate in the cortical bone of the tibia was reduced with a parallel reduction in endosteal osteoid seam width. Both calcification rate and tetracycline double-labeled surface of vertebral trabecular bone were reduced during the first 2 weeks. Neither total bone resorption surface nor active bone resorption surface were increased. There was a decrease in osteoclast numbers/mm2 bone tissue associated with decreasing bone volume. Our data demonstrate a transient inhibition of bone formation during acute inflammation in the rat and indicate that changes in osteoblast function are part of the acute phase response following local inflammation.

[Treatment of tumor hypercalcemia with clodronate. Effect on parathormone and calcitriol]

Clodronate (dichlormethylene diphosphonate) was administered to 21 patients with hypercalcemia due to malignant tumor. The drug was initially given intravenously, then orally. In 20 patients the serum calcium level had been reduced to the normal range within one week of the start of treatment (from 3.3 +/- 0.5 mmol/l to 2.4 +/- 0.3 mmol/l). With oral administration there was a renewed rise in calcium levels in some patients, which had to be treated with higher oral doses or intravenous administration. Parallel with the reduction in calcium levels there was an improvement in the originally impaired renal function. The serum level of intact parathormone(1-84) and 1.25-dihydroxy-vitamin-D3 (calcitriol) rose significantly from usually lowered initial levels. There was a non-linear inverse correlation between parathormone and calcium. No side effects were noted, even after long-term administration.