Treatment of Paget's disease with combined calcitonin and diphosphonate (EHDP)

Biochemical assessment of acute and chronic treatment of Paget's bone disease with calcitonin and calcium with and without biphosphonate

Response to acute and chronic administration of calcitonin and calcium and of biphosphonates (EHDP) was evaluated in 14 patients with Paget's bone disease who were grouped on the basis of homogeneous disease activity, as appraised by bone involvement and alkaline phosphatase and hydroxyproline levels. At first, 100 MRC U of calcitonin followed 4 hours later by 500 mg of elemental calcium were given for 10 days; a significant (p less than 0.001; paired and unpaired Student t test) reduction in alkaline phosphatase (-25%) and hydroproline (-55%) was observed. Subsequently, 5 mg/kg/day of EHDP was given for 20 days. Both parameters increased to levels similar to basal values. These increases were significant (p less than 0.001 for the paired and unpaired Student test) compared with those obtained after calcitonin administration; alkaline phosphatase rose +27% and hydroxproline +135%. After this, patients were divided into 2 groups (A and B). Group A was treated with calcitonin and calcium, at the dosage indicated above, for 10 days a month during 6 months. Group B continued with the same protocol with the addition of EHDP for the 20 days during which calcitonin and calcium were not given. The results of 6 months of treatment showed that calcitonin was more active and suggested that EHDP diminishes hormonal effects. These results also demonstrate a short-term absence of EHDP activity.

Biochemical response to combination of disodium etidronate with calcitonin in Paget's disease

The biochemical responses to salmon calcitonin (SCT: 100 MRC units thrice weekly) and disodium etidronate (EHDP: 400 mg daily) alone and in combination for 6 months were compared in 72 patients with symptomatic Paget's disease of bone unresponsive to simple analgesic agents. SCT produced a 53% reduction in alkaline phosphatase (AP) and a 38% reduction in 24 h urinary hydroxyproline excretion (HYPRO). The response to EHDP was not significantly different--56% reduction in AP and 48% reduction in HYPRO. Their use in combination produced a significantly greater reduction of 71% in AP (P less than 0.002) and 69% reduction in HYPRO (P less than 0.0001). In those that remained symptomatic with increased disease activity treatment for longer than 6 months had a unpredictable effect and normal bone turnover was rarely achieved. Once therapy was withdrawn AP and HYPRO increased rapidly in those given SCT alone, returning to initial levels within 6 months. More sustained control of disease activity was achieved in those given EHDP either alone or with SCT but the combination retained the advantage obtained during treatment. Combinations of SCT + EHDP may find a place in the treatment of very active Paget's disease.

Quantitative bone scintigraphy in Paget's disease treated with APD

Half-yearly bone scintigrams of 27 patients with Paget's disease, who were treated with the bisphosphonate APD, were evaluated. Uptake of 99Tcm-Sn-EHDP was determined by computer analysis. All patients reached clinical and biochemical remission, usually within 6 months. The scintigraphic uptake dropped steeply during the first 6 months and only slightly during the second 6 months. The decrease in uptake was proportional to the original uptake and averaged 80% of this value. The residual 20% persisted, although clinical and biochemical remission were attained. The scintigraphic results obtained with APD agree with our earlier findings for patients in remission after treatment with a combination of calcitonin and EHDP. Eight patients suffered a recurrence after discontinuation of APD. In all cases scintigraphic deterioration also occurred, usually simultaneously or 6 months before the recurrence. In two patients with scintigraphic deterioration a recurrence could not be confirmed during this study. The scintigraphic deterioration presented as one of the three patterns seen after combination therapy.

Radiological demonstration of healing in Paget's disease of bone treated with APD

Twenty-three patients with Paget's disease received the bisphosphonate APD and were examined radiologically every 6 months. Because routine roentgenographic procedures were followed, a number of the X rays were not fit for comparison. The radiographic technique, as well as the positioning of the patients, is critical since both could lead to artefacts. All patients reached normal biochemical levels, usually within 6 months. Out of the 23 patients 11 showed definite radiological improvement in one or more lesions; probable improvement was seen in another three. Of the 65 individual lesions, with films that were comparable, 30% definitely and 20% probably improved; 50% did not change but deterioration was never encountered. Osteolytic lesions in the long bones are most suitable for the evaluation of radiological changes and follow-up of these lesions during treatment should be most rewarding.

Long-term controlled trial with diphosphonate in patients with osteolytic bone metastases

Thirty-four normocalcaemic women with multiple osteolytic bone metastases from breast cancer were randomly allocated to treatment with disodium dichloromethylene diphosphonate (Cl2MDP) 1600 mg/day orally (17) or placebo (17) for 3-9 months. Fasting urinary hydroxyproline/creatinine and calcium/creatinine ratios declined in the Cl2MDP group but not in the placebo group. Four patients in the placebo group died from hypercalcaemia. New bone metastases were more common in patients on placebo and these patients also required more analgesic drugs than those on Cl2MDP. Cl2MDP seemed to reduce bone pain and bone resorption and prevent the development of hypercalcaemia caused by osteolytic metastases. The formation of new bone metastases and the growth of old ones seemed to be retarded by Cl2MDP.

Bone scintigraphy in Paget's disease treated with combined calcitonin and diphosphonate (EHDP)

Bone scintigraphic results for 28 patients with Paget's disease treated with a combination of EHDP and calcitonin are reported. The uptake of the bone scintigraphic agent decreased considerably during the first year of treatment. There was good correlation between scintigraphic and biochemical changes, but most of the 22 patients who attained normal biochemical values still had one or more active lesions scintigraphically. Remission of disease does not therefore mean normalization of the bone scintigram. All affected bones showed a distinct drop in activity, but lesions with a higher initial activity remained more active than lesions with a lower initial activity. One third of the affected bones normalized completely, although radiographic anomalies persisted. There were slight differences in scintigraphic activity depending on the anatomical site. The success of treatment, however, could not be predicted from the pretreatment scintigram. A recurrence of disease was often visible on the scintigram, in certain cases 6 months prior to the biochemical decline. This could be of importance in the therapeutic management of the recurrence.

Effects of ethane-1 hydroxy-1, 1-diphosphonate (5 mg/kg/day dose) on quantitative bone histology in Paget's disease of bone

The effects of ethane hydroxy diphosphonate (EHDP) on quantitative bone histology have been studied in 43 pagetic patients treated for 6 months at a dose of 5 mg/kg/day. To determine the therapeutic effects on pagetic bone and to appreciate the side effects in non-pagetic bone, the patients were biopsied either in pagetic or non-pagetic areas of the ilium before the beginning of the treatment and at 3, 6 and 9 months (i.e. 3 months post-therapy) after the inception of treatment. Tetracycline double labelling of bone was performed before biopsies in each patient to measure the calcification rate. The results demonstrate that 5 mg/kg/day EHDP given for 6 months has a marked antiosteoclastic effect which is prolonged after the cessation of treatment. Pagetic osteoclasts appear more sensitive to EHDP than normal osteoclasts. The new bone formed during treatment has a regular lamellar texture. At the same time, the high appositional rate of pagetic bone is reduced to a normal value. Marrow fibrosis is reduced along with the reduction in the osteoclast population. Thus, pagetic bone changes to bone normal in quantity, quality and metabolism. Dynamically, in nonpagetic areas, a transitory decrease of calcification rate is noted at the end of the treatment, without morphological evidence of osteomalacia, except for 2 out of 43 cases. Histologically, EHDP given at a dose of 5 mg/kg/day for 6 months appears to be an effective and safe treatment for Paget's disease of bone.

Calcitonin and diphosphonate in the treatment of Paget's disease of bone

The ideal treatment for Paget's disease of bone should control turnover irrespective of its initial activity and produce a sustained remission once treatment is withdrawn. Unfortunately, neither the calcitonins nor the diphosphonates currently available entirely fulfil these requirements. Preliminary studies suggest that combinations of calcitonin and EHDP produce significantly better responses than those of the individual agents alone. This proposition is examined critically in terms of the optimum effects achieved with calcitonin and EHDP alone paying particular attention to variables such as disease activity, dose and duration of treatment.

Salmon calcitonin therapy for Paget's disease of bone. The problem of acquired clinical resistance

During the initial months of long-term treatment of Paget's disease of bone with salmon calcitonin, circulating alkaline phosphatase activity and urinary hydroxyproproline excretion usually decrease by about 50%. In 22 of 85 patients these parameters returned to pretreatment levels despite continuous therapy. Nineteen patients who were resistant to salmon calcitonin had salmon calcitonin antibodies in high titer. Human calcitonin has been effective in suppressing disease activity in these patients. The pathogenesis of calcitonin resistance in patients without antibodies is unknown.

Treatment of Paget's disease with (3-amino-1-hydroxypropylidene)-1, 1-bisphosphonate (A.P.D.)

18 patients with Paget's disease were treated orally with (3-amino-1-hydroxypropylidene)-1, 1-bisphosphonate (A.P.D.). In most cases bone resorption became normal within a week of treatment, whereas the return to normal bone formation took 3-6 months; this difference produced a transient imbalance between resorption and formation. In biopsy specimens taken during treatment the numbers of osteoclasts and osteoblasts decreased towards normal and excess osteoid disappeared.