Intranasal salcatonin (salmon calcitonin). A review of its pharmacological properties and role in the management of postmenopausal osteoporosis

Evaluation of the efficacy of salmon calcitonin nasal spray on bone healing following open reduction and internal fixation of mandibular fractures - A randomized controlled trial

The objective of this study was to assess the efficacy of calcitonin spray on bone healing following open reduction internal fixation (ORIF) of mandibular fractures. Fourteen patients were subdivided into a study group and a control group. A standardized surgical protocol for ORIF was followed. Postoperatively, salmon calcitonin nasal spray was administered to only the study group. The outcome parameters assessed were serum osteocalcin, pain, and radiographic bone healing. Serum osteocalcin was assessed pre- and postoperatively. Postoperative pain was documented using a visual analogue scale (VAS) on the 7th, 14th, 23rd, and 30th days. An orthopantomogram was used to score fracture healing at four time intervals, as follows: 1 - absence of callus; 2 - presence of minimal callus; 3 - considerable callus; and 4 - complete fusion of fracture. Pain scores were lower for the study group, with no pain from the fifth day, while the control group produced a mean score for day 5 of 2.43 ± 0.98 (p = 0.001). Mean postoperative serum osteocalcin levels were higher for the study group (67.82 ± 8.89) compared with the control group (57.69 ± 6.22; p = 0.029). Bone healing at 12 weeks postoperatively was level 4 for 28.6% of patients in the study group and level 3 for 71.4%. In comparison, 85.7% in the control group demonstrated level 3 healing, while 14.3% remained at level 2 (p = 0.462). Within the limitations of the study, it can be concluded that intranasal salmon calcitonin spray reduces postoperative pain and facilitates fracture healing, although its economic efficiency is still to be proven.

Overview of intranasally delivered peptides: key considerations for pharmaceutical development

INTRODUCTION

Intranasal (IN) delivery for peptides provides unique advantages compared to other invasive systemic delivery routes. However, there still lacks a clear understanding on how to evaluate the potential of the peptides for nasal delivery and key considerations for the nasal formulation development.

AREAS COVERED

A retrospective analysis of intranasally delivered peptides was conducted. The goals of this undertaking were 1) to build a database of the key physicochemical and pharmacokinetic properties of peptides delivered by the nasal route, 2) to evaluate formulation attributes applied to IN peptide delivery systems, and 3) to provide key considerations for IN delivery of peptides.

EXPERT OPINION/COMMENTARY

Extensive data mining showed that peptides with molecular weights up to 6000 Da have been delivered intranasally. The high solubility of some peptides highlighted the possibility of delivering sufficient amounts of peptide in the limited volume available for nasal sprays. Permeation enhancers and mucoadhesives have shown promise in improving the IN bioavailability of peptides. Other formulation considerations, such as the type of formulation, pH, osmolality, as well as drug deposition, are reviewed herein. Based on this retrospective analysis, key considerations for nasal peptides formulations were proposed to guide drug discovery and development for IN delivery of peptides.

Effect of Intranasal Calcitonin in a Patient with McCune-Albright Syndrome, Fibrous Dysplasia, and Refractory Bone Pain

McCune-Albright syndrome (MAS) is a rare disease defined by the triad of polyostotic fibrous dysplasia of bone, café-au-lait skin spots, and precocious puberty. No available treatment is effective in changing the course of fibrous dysplasia of bone, but symptomatic patients require therapeutic support to reduce bone pain and prevent fractures and deformities. We report the case of a 27-year-old woman with MAS and severe fibrous dysplasia. She was diagnosed with MAS at 4 years of age and, during follow-up, she had multiple pathological fractures and bone pain refractory to treatment with bisphosphonates, tricyclic antidepressants, and opioids. The pain was incapacitating and the patient required a wheelchair. Intranasal calcitonin was then started, and, 30 days later, the patient already showed significant improvement in pain severity at the affected sites. After 3 months, she was able to walk without assistance. No adverse effects were observed, nor were any significant changes in serum levels of calcium, phosphorus, and alkaline phosphatase. Calcitonin has a well-recognized analgesic effect on bone tissue. Despite the small number of studies involving patients with MAS, calcitonin may be considered a short-term therapeutic option in cases of severe and refractory bone pain.

Additive effect of elcatonin to risedronate for chronic back pain and quality of life in postmenopausal women with osteoporosis: a randomized controlled trial

Calcitonin has been reported to reduce acute and chronic back pain in osteoporotic patients. The additive effect of calcitonin with a bisphosphonate on chronic back pain remains unclear. The purpose of this study was to evaluate the effect of combining elcatonin (eel calcitonin) with risedronate for patients with chronic back pain. Forty-five postmenopausal women diagnosed as having osteoporosis with chronic back pain persisting for more than 3 months, after excluding women with fresh vertebral fractures within the last 6 months, were randomly allocated to a risedronate group (risedronate alone, n = 22) and a combined group (risedronate and elcatonin, n = 23). The study period was 6 months. Pain was evaluated with a visual analogue scale (VAS) and the Roland-Morris questionnaire (RDQ). Back extensor strength, bone mineral density, and quality of life on the SF-36 and the Japanese osteoporosis quality of life score were also evaluated. Significant improvements were found in the combined group for VAS at final follow-up compared with baseline and 3 months, mental health status on the SF-36, and JOQOL domains for back pain and general health. The JOQOL domain for back pain improved significantly, but no change was found in the VAS or other domains in the risedronate group. Bone mineral density increased significantly in the two groups, but no significant difference was found between the groups. Back extensor strength did not change in both groups. In conclusion, the use of elcatonin in addition to risedronate for more than 3 months reduced chronic back pain. The additional therapy of risedronate with elcatonin may be a useful and practical choice for the treatment of osteoporosis with chronic back pain persisting more than 3 months.

European guidance for the diagnosis and management of osteoporosis in postmenopausal women

Guidance is provided in a European setting on the assessment and treatment of postmenopausal women at risk of fractures due to osteoporosis.

INTRODUCTION

The International Osteoporosis Foundation and European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis published guidance for the diagnosis and management of osteoporosis in 2008. This manuscript updates these in a European setting.

METHODS

Systematic literature reviews.

RESULTS

The following areas are reviewed: the role of bone mineral density measurement for the diagnosis of osteoporosis and assessment of fracture risk, general and pharmacological management of osteoporosis, monitoring of treatment, assessment of fracture risk, case finding strategies, investigation of patients and health economics of treatment.

CONCLUSIONS

A platform is provided on which specific guidelines can be developed for national use.

Metabolism and disposition of the oral absorption enhancer 14C-radiolabeled 8-(N-2-hydroxy-5-chlorobenzoyl)-amino-caprylic acid (5-CNAC) in healthy postmenopausal women and supplementary investigations in vitro

8-(N-2-hydroxy-5-chlorobenzoyl)-amino-caprylic acid (5-CNAC), a compound lacking pharmacological activity enhances the absorption of salmon calcitonin, when co-administered. Disposition and biotransformation of 5-CNAC was studied in six healthy postmenopausal women following a single oral dose of 200mg (14)C-radiolabeled 5-CNAC (as disodium monohydrate salt). Blood, plasma, urine and feces collected over 7 days were analyzed for radioactivity. Metabolite profiles were determined in plasma and excreta and metabolite structures were elucidated by LC-MS/MS, LC-(1)H NMR, enzymatic methods and by comparison with reference compounds. Oral 5-CNAC was safe and well tolerated in this study population. 5-CNAC absorption was rapid (t(max)=0.5h; C(max)=9.00 ± 2.74 μM (mean ± SD, n=6) and almost complete. The elimination half-life (t(½)) was 1.5 ± 1.1h. The radioactive dose was excreted mainly in urine (≥ 90%) in form of metabolites and 0.071% as intact 5-CNAC. Excretion of radioactivity in feces was minor and mostly as metabolites (<3%). Radioactivity in plasma reached C(max) (35.4 ± 7.9 μM) at 0.75 h and declined with a half-life of 13.9 ± 4.3h. 5-CNAC accounted for 5.8% of the plasma radioactivity AUC(0-24h). 5-CNAC was rapidly cleared from the systemic circulation, primarily by metabolism. Biotransformation of 5-CNAC involved: (a) stepwise degradation of the octanoic acid side chain and (b) conjugation of 5-CNAC and metabolites with glucuronic acid at the 2-phenolic hydroxyl group. The metabolism of 5-CNAC in vivo could be reproduced in vitro in human hepatocytes. No metabolism of 5-CNAC was observed in human liver microsomes.

Effects of calcitonin on knee osteoarthritis and quality of life

There has been a recent interest in calcitonin as a potential treatment for osteoarthritis, based on its metabolic activities in both bone turnover and cartilage. The aim of this study was to evaluate the effects of nasal form calcitonin on knee osteoarthritis and quality of life in women who receive calcitonin treatment for postmenopausal osteoporosis. Two hundred and twenty postmenopausal women, aged between 55 and 65 years with knee pain and knee osteoarthritis, graded II-III by using Kellgren-Lawrence radiographic scoring system, were included. Western Ontario and McMaster Universities (WOMAC) osteoarthritis index, the quality of life questionnaire of the European Foundation for Osteoporosis (QALEFFO-41) and visual analog scale were used for the algofunctional assessments. Need of rescue analgesic was recorded. Pain (P < 0.001), stiffness (P < 0.05), functional capability (P < 0.05) and total score of WOMAC (P < 0.05) revealed statistically significant improvements after 3 months of the treatment and remained consistent throughout 1 year of the treatment period. Participants experienced significant reductions in WOMAC perceptions of pain (-53 %), joint stiffness (-44 %) and limitations in physical function (-49 %) at the end of 1 year of calcitonin treatment. Need of rescue analgesic intake was reported to have decreased approximately by 60 % at the end of the 1-year treatment period. QUALEFFO_41 scores improved: 37.6 (baseline), 30.9 (3 months), 28.0 (6 months) and 24.4 (1 year). In conclusion, nasal calcitonin treatment provided dual action on osteoporosis and osteoarthritis with significant improvements in quality of life and algofunctional results in knee osteoarthritis.

Calcitonin for treating acute and chronic pain of recent and remote osteoporotic vertebral compression fractures: a systematic review and meta-analysis

Vertebral collapse is a common fracture associated with osteoporosis. Subsequent pain may be severe and often requires medications and bed rest. Several studies have suggested the use of calcitonin for the treatment of fracture pain. We sought to determine the analgesic efficacy of calcitonin for acute and chronic pain of osteoporotic vertebral compression fractures (OVCF). We searched for randomized, placebo, and controlled trials that evaluated the analgesic efficacy of calcitonin for pain attributable to OVCFs. We performed meta-analyses to calculate standardized mean differences (SMDs) using a fixed or random effects model. The combined results from 13 trials (n = 589) determined that calcitonin significantly reduced the severity of acute pain in recent OVCFs. Pain at rest was reduced by week 1 [mean difference (MD) = -3.39, 95% confidence interval (CI) = -4.02 to -2.76), with continued improvement through 4 weeks. At week 4, the difference in pain scores with mobility was even greater (SMD = -5.99, 95% CI = -6.78 to -5.19). For patients with chronic pain, there was no statistical difference between groups while at rest; there was a small, statistically significant difference between groups while mobile at 6 months (SMD = 0.49, 95% CI = -0.85 to -0.13, p = 0.008). Side effects were mild, with enteric disturbances and flushing reported most frequently. Although calcitonin has proven efficacy in the management of acute back pain associated with a recent OVCF, there is no convincing evidence to support the use of calcitonin for chronic pain associated with older fractures of the same origin.

Calcitonin: a drug of the past or for the future? Physiologic inhibition of bone resorption while sustaining osteoclast numbers improves bone quality

Postmenopausal osteoporosis results from a continuous imbalance between bone resorption and bone formation, favoring bone resorption. An increasing number of treatments for osteoporosis are in development and on the market. A range of differences and similarities are found between these treatment options, and these need to be carefully evaluated before the initiation of treatment. This article summarizes data from in vitro and animal studies, as well as clinical trials, on the effect of calcitonin on bone turnover. Calcitonin was found to exert its antiresorptive effects via directly reducing osteoclastic resorption, and thus leads to an increase in bone mineral density and bone strength. Furthermore, calcitonin appears to mainly target the most active osteoclasts, and in contrast to most other antiresorptive agents it does not reduce the number of osteoclasts. Finally, in humans, while attenuating resorption, calcitonin treatment does not interfere markedly with bone formation, in contrast to other currently available antiresorptive agents. Thus, we speculate that calcitonin treatment will lead to a continuously positive bone balance in contrast with other antiresorptive agents currently on the market and thereby, in a physiologic manner, result in improved bone quality. Calcitonin is currently only available in injectable and nasal formulations. An oral formulation may, however, improve patient acceptance and compliance. Currently, several different routes are being pursued to identify an optimal oral formulation, of which the technology based on 5-CNAC is the most advanced. There are promising clinical data available for this formulation from both osteoarthritis and osteoporosis clinical trials, although the antifracture efficacy is not yet known.

European guidance for the diagnosis and management of osteoporosis in postmenopausal women

Guidance is provided in a European setting on the assessment and treatment of postmenopausal women with or at risk from osteoporosis.

INTRODUCTION

The European Foundation for Osteoporosis and Bone disease (subsequently the International Osteoporosis Foundation) published guidelines for the diagnosis and management of osteoporosis in 1997. This manuscript updates these in a European setting.

METHODS

The following areas are reviewed: the role of bone mineral density measurement for the diagnosis of osteoporosis and assessment of fracture risk; general and pharmacological management of osteoporosis; monitoring of treatment; assessment of fracture risk; case finding strategies; investigation of patients; health economics of treatment.

RESULTS AND CONCLUSIONS

A platform is provided on which specific guidelines can be developed for national use.

Salmon calcitonin: a review of current and future therapeutic indications

Salmon calcitonin, available as a therapeutic agent for more than 30 years, demonstrates clinical utility in the treatment of such metabolic bone diseases as osteoporosis and Paget's disease, and potentially in the treatment of osteoarthritis. This review considers the physiology and pharmacology of salmon calcitonin, the evidence based research demonstrating efficacy and safety of this medication in postmenopausal osteoporosis with potentially an effect on bone quality to explain its abilities to reduce the risk of spine fracture, the development of an oral salmon calcitonin preparation, and the therapeutic rationale for this preparation's chondroprotective effect in osteoarthritis.

Intranasal complications in women with osteoporosis under treatment with nasal calcitonin spray: case reports and review of the literature

OBJECTIVE

To describe the nasal side effects of postmenopausal women suffering from osteoporosis and being treated with intranasal calcitonine (InC).

METHOD

Two women who presented with nasal complaints, were diagnosed as having nasal septum perforation and septum-concha inferior synechiae respectively. Both were receiving treatment with InC for postmenopausal osteoporosis. A medline search for similar side effects of InC revealed a range of nasal symptoms and several factors that could induce these symptoms.

RESULTS

Exclusion of other causative conditions leads us to attribute the nasal findings to the use of InC. The literature mentions mild and usually reversible side effects from use of InC. Substances included in the calcitonine spray (preservatives, accelerators of absorption), the development of antibodies against the hormone and possible implication of coexisting diseases or medications to the provocation of nasal side effects, are discussed.

CONCLUSIONS

Intranasal administration of calcitonine is an established therapy for postmenopausal osteoporosis and other skeletal diseases. The side effects from its use are commonly local, mild and transient, but there is not sufficient information on how this process begins. An ENT examination before and during therapy with InC would be beneficial to patients for the recognition and prevention of serious side effects.

Tolerability, safety and pharmacokinetics of the FGLL peptide, a novel mimetic of neural cell adhesion molecule, following intranasal administration in healthy volunteers

BACKGROUND

The FG loop peptide (FGL(L)), a novel mimetic of the neural cell adhesion molecule (NCAM), is in clinical development for neurodegenerative disorders such as Alzheimer's disease. Preclinical studies in rats, dogs and monkeys have demonstrated exposure in plasma and cerebrospinal fluid after parenteral or intranasal administration of FGL(L), with no systemic toxicity. This article reports on the results of the first administration of FGL(L) in humans.

OBJECTIVE

To determine the tolerability, safety and pharmacokinetics of ascending, single intranasal doses of FGL(L) 25, 100 and 200mg in healthy subjects.

METHODS

In an 8-day, open-label, phase I study, 24 healthy male volunteers (mean age 42 [range 24-55] years) received single intranasal doses of FGL(L) (25, 100 and 200mg) in accordance with an ascending dose, sequential-cohort design.

RESULTS

All three intranasal doses of FGL(L) were well tolerated and there were no clinical notable abnormalities in ECG recordings, vital signs or laboratory tests. Three subjects (13%) reported five adverse events. A transient (<3 minutes) burning sensation in the nose was reported in two subjects at the 200mg dose level while runny eyes (<2 minutes) were experienced in one subject at 25mg. These events had an onset immediately following intranasal administration, and a relationship to FGL(L) was suspected. One of the latter subjects who had experienced a burning sensation in the nose also experienced dizziness, vomiting and headache with onset >2 days after single-dose administration of FGL(L); no relationship to the study drug was suspected. Quantifiable plasma concentrations of FGL(L) were observed up to 1 hour after intranasal administration of the 100mg dose and up to 4 hours after the 200mg dose (plasma FGL(L) concentrations were undetectable at all timepoints for the 25mg dose). Increasing doses of FGL(L) were associated with higher systemic exposures: mean C(max) 0.52 ng/mL and 1.38 ng/mL (100mg and 200mg, respectively); mean AUC(24) 1.27 ng x h/mL and 4.05 ng x h/mL (100mg and 200mg, respectively).

CONCLUSIONS

Intranasal administration of FGL(L) (25, 100 and 200mg) was well tolerated in healthy male volunteers, with no safety concerns and a pharmacokinetic profile that was generally dose related. Further studies are currently being planned to evaluate the effects of FGL(L) in patients with Alzheimer's disease.

Phase I clinical trial in healthy adults of a nasal vaccine candidate containing recombinant hepatitis B surface and core antigens

BACKGROUND

The nasal vaccine candidate (NASVAC), comprising hepatitis B virus (HBV) surface (HBsAg) and core antigens (HBcAg), has been shown to be highly immunogenic in animal models.

METHODS

A phase I double-blinded, placebo-controlled randomized clinical trial was carried out in 19 healthy male adults with no serologic markers of immunity/infection to HBV. This study was aimed at exploring the safety and immunogenic profile of nasal co-administration of both HBV recombinant antigens. The trial was performed according to Good Clinical Practice guidelines. Participants ranged in age from 18 to 45 years and were randomly allocated to receive a mixture of 50 microg HBsAg and 50 microg HBcAg or 0.9% physiologic saline solution, as a placebo, via nasal spray in a five-dose schedule at 0, 7, 15, 30, and 60 days. A total volume of 0.5 ml was administered in two dosages of 125 microl per nostril. Adverse events were actively recorded 1 h, 6 h, 12 h, 24 h, 48 h, 72 h, 7 days and 30 days after each dose. Anti-HBs and anti-HBc titers were evaluated using corresponding ELISA kits at days 30 and 90.

RESULTS

The vaccine candidate was safe and well tolerated. Adverse reactions included sneezing (34.1%), rhinorrhea (12.2%), nasal stuffiness (9.8%), palate itching (9.8%), headache (9.8%), and general malaise (7.3%). These reactions were all self-limiting and mild in intensity. No severe or unexpected events were recorded during the trial. The vaccine elicited anti-HBc seroconversion in 100% of subjects as early as day 30 of the immunization schedule, while a seroprotective anti-HBs titer (>or=10 IU/l) was at a maximum at day 90 (75%). All subjects in the placebo group remained seronegative during the trial.

CONCLUSION

The HBsAg-HBcAg vaccine candidate was safe, well tolerated and immunogenic in this phase I study in healthy adults. To our knowledge, this is the first demonstration of safety and immunogenicity for a nasal vaccine candidate comprising HBV antigens.

Calcitonin is involved in cartilage homeostasis: is calcitonin a treatment for OA?

OBJECTIVE

Osteoarthritis (OA) is the most common form of degenerative joint diseases and a major cause of disability and impaired quality of life in the elderly. Recent observations suggest that calcitonin may act on both osteoclasts and chondrocytes. The present review was sought to summarize emerging observations from the molecular level to the preliminary clinical findings of possible chondroprotective effects of calcitonin.

METHOD

This review summarizes peer-reviewed articles found using pre-defined search criteria and published in the PubMed database before January 2006. In addition, abstracts from the OsteoArthritis Research Society International (OARSI) conferences in the time period 2000-2005 have been included in the search.

RESULTS

Ample evidence for the effect of calcitonin on bone resorption was found. Support for direct effects of calcitonin on chondrocytes on matrix synthesis and inhibition of cartilage degradation have been published. In addition, clinical evidence for the effect of calcitonin on cartilage degradation is emerging.

CONCLUSION

Several independent lines of evidence suggest a direct chondroprotective effect of calcitonin in addition to the well-established effect on bone resorption. Given the currently limited availability of chondroprotective agents, much expectation regards the ongoing clinical assessment of calcitonin therapy for the prevention and treatment of OA.

Calcitonin for treating acute pain of osteoporotic vertebral compression fractures: a systematic review of randomized, controlled trials

Vertebral collapse is one of the most common fractures associated with osteoporosis. The subsequent back pain is severe and often requires medications, bed rest and hospitalization to control pain and improve mobilization. The purpose of this systematic review was to assess the effects of calcitonin versus placebo for the treatment of acute pain in patients sustaining stable, recent, osteoporotic vertebral compression fractures. MEDLINE (1966-2003), EMBASE (1980-2003), Cochrane Controlled Trial Registry (2003, volume 3), other databases, and conference proceedings were searched for relevant research. Primary study authors and the pharmaceutical manufacturer were contacted, and bibliographies of relevant papers were hand-searched. Randomized, double-blind, placebo-controlled trials comparing calcitonin versus placebo for the acute pain of recent osteoporotic vertebral compression fractures were included. Two reviewers extracted data, performed numeric calculations and extrapolated graphical data independently. The combined results from five randomized controlled trials, involving 246 patients, determined that calcitonin significantly reduced the severity of pain using a visual analogue scale following diagnosis. Pain at rest was reduced as early as 1 week into treatment (weighted mean difference [WMD] =3.08; 95% confidence interval [CI]: 2.64, 3.52) and this effect continued weekly to 4 weeks (WMD =4.03; 95% CI: 3.70, 4.35). A similar pattern was seen for pain scores associated with sitting, standing, and walking. Side effects were gastrointestinal, minor and often self-limited. Calcitonin appears to be effective in the management of acute pain associated with acute osteoporotic vertebral compression fractures by shortening time to mobilization.

Nasal absorption and pharmacokinetic disposition of salmon calcitonin modified with low molecular weight polyethylene glycol

This study was performed to examine the absorption potential of polyethylene glycol (PEG)-modified salmon calcitonin (sCT) in rats administered via the nasal route. Previous studies have used relatively high molecular weight polyethylene glycols (e.g., > or =5000 daltons) for PEG-modification of sCT to provide increased metabolic stability and biological half-life. Unlike these studies, the present study utilized a low molecular weight succinimidyl-propionated monomethoxy-poly(ethylene glycol) (MW 2000). It was hypothesized that the potential for membrane transport would not be significantly altered due to a relatively small increase in the molecular size while the metabolic stability would be enhanced due to resistance to proteolytic degradation. After PEG-modification of sCT, the mono-PEG positional isomer (mono-PEG2k-sCT) was separated from di-PEG2k-sCT, tri-PEG2k-sCT, and unmodified sCT by size exclusion chromatography. The mono-PEG2k-sCT and unmodified sCT were radioiodinated, and the resulting 125I-sCT and 125I-mono-PEG2k-sCT were separated from free iodine by RP HPLC and confirmed by MALDI-TOF MS. The 125I-sCT and 125I-mono-PEG2k-sCT were administered to rats via the nasal route, and serial blood, tissue, and urine samples were taken for up to 36 h for the determination of radioactivity. Mono-PEG2k-sCT exhibited significantly increased AUC (20,638 vs. 3,650 ng.min/ml), tmax (520 vs. 77 min), and t1/2,lambdaz (923 vs. 199 min) compared with unmodified sCT. This study demonstrates that mono-PEG2k-sCT is absorbed systemically when given by the intranasal route, exhibiting altered absorption kinetics compared with unmodified sCT.

Calcitonin intranasal--unigene: Salcatonin intranasal--unigene

An intranasal spray formulation of recombinant salmon calcitonin [salcatonin] is in development with Unigene Laboratories as therapy for postmenopausal osteoporosis. Calcitonin is an endogenous polypeptide hormone that regulates calcium and bone metabolism. It is produced by the parafollicular cells of the thyroid gland in humans and other species. Calcitonin inhibits bone loss through the suppression of osteoclast activity. Salmon calcitonin is approximately 40-50 times more potent than natural human calcitonin at inhibiting osteoclast function. It can be obtained naturally from salmon or can be synthesised with the same chemical structure. Calcitonin was originally available only as an injectable formulation, but in recent years more convenient formulations have become available. Unigene is actively seeking to license its intranasal calcitonin product in Europe and other territories outside the US. nigene licensed its intranasal calcitonin product to Upsher-Smith Laboratories in December 2002, under a $US10 million exclusive US licensing agreement. Under the terms of the agreement, Unigene received an upfront payment of $US3 million from Upsher-Smith and will be eligible to receive milestone payments and royalty payments on product sales. Unigene will be responsible for manufacturing the product at its Boonton facility in New Jersey, USA, and will sell finished calcitonin product to Upsher-Smith. Upsher-Smith will package, market and distribute the product nationwide. Unigene granted an exclusive license to Faran Laboratories in September 2003 for its intranasal calcitonin osteoporosis product in Greece. Unigene will sell the finished product to Faran, who will promote and market it throughout the country after Unigene obtains European regulatory approval and local pricing approval. Unigene will receive an upfront payment and is eligible to receive milestone payments prior to product launch. Faran will pay Unigene a fixed price for each unit of product received. Qingdao General Pharmaceutical Company was a licensee for Unigene's injectable and intranasal calcitonin products in the People's Republic of China, and Unigene had received initial payments from Qingdao General Pharmaceutical in 1996. However, in June 2000, Unigene announced that it has entered into a joint venture with Shijiazhuang Pharmaceutical Group Company for the manufacture and distribution of injectable and intranasal calcitonin for the treatment of osteoporosis in China. Unigene initially will be responsible for supplying bulk calcitonin manufactured in its production facility in New Jersey and the joint venture will be responsible for filling, packaging, promoting and marketing the products. Unigene owns 45% of the contractual joint venture. Unigene is also developing oral and injectable formulations of calcitonin. In January 2004, Unigene announced it had received an approvable letter from the US FDA to market its calcitonin intranasal spray for the treatment of osteoporosis. The letter indicates that the FDA will approve the NDA upon finalisation of the labelling and resolution of specific remaining issues, including the submission of additional information and clinical data. Unigene filed the NDA in March 2003. Using the results from a pilot study completed in the UK, Unigene filed an IND with the FDA and began clinical testing of this intranasal calcitonin in the US. Clinical studies were successfully completed by year end 2001, demonstrating significant bone marker activity and similar serum concentrations between this product and that of an existing nasal calcitonin product. The European Union's regulatory authority, the Committee for Proprietary Medicinal Products (CPMP), has confirmed the efficacy of calcitonin formulations for the treatment of postmenopausal osteoporosis and other bone disorders. The CPMP has recommended revisions to and harmonisation within the European Union of the authorised indications for calcitonin formulations. The CPMP has determined that authorised indications for intranasal calcitonin will be approved for "treatment of established post-menopausal osteoporosis in order to reduce the risk of vertebral fractures", and new prescribing information will clarify that intranasal calcitonin does not appear to reduce the number of hip fractures. These recommendations will be implemented in the near future and will eliminate discrepancies between countries and between formulations. The Chinese regulatory authorities have granted Unigene an import license for calcitonin, and Unigene and Shijiazhuang have submitted an NDA in China. If this NDA is approved, the joint venture will have up to 6 years' market exclusivity for intranasal and injectable calcitonin. Unigene was granted a US patent for the intranasal formulation of calcitonin in 2002.

Analgesic efficacy of calcitonin for vertebral fracture pain

OBJECTIVE

To evaluate the analgesic efficacy of calcitonin for treating the pain of vertebral fractures associated with osteoporosis.

DATA SOURCES

Searches of MEDLINE (1966-July 2002), Cochrane Library, International Pharmaceutical Abstracts (1977-July 2002), and an extensive manual review of journals were performed using the key search terms calcitonin, analgesic, osteoporosis, vertebral fracture, and pain.

STUDY SELECTION AND DATA EXTRACTION

All articles identified from the data sources were evaluated and all information deemed relevant was included for this review.

DATA SYNTHESIS

Fractures, especially vertebral fractures, are a common complication of osteoporosis, leading to significant pain. Calcitonin has been studied for its analgesic properties. Fourteen double-blind, placebo-controlled trials that evaluated the analgesic efficacy of calcitonin for osteoporosis-related vertebral fracture pain were identified and reviewed. Thirteen of these studies demonstrated statistically significant improvement in pain or function in calcitonin-treated patients.

CONCLUSIONS

Calcitonin has proven efficacy in acute pain associated with osteoporosis-related vertebral fractures. Analgesic effects are seen with intranasal, parenteral, and rectal administration. Future studies comparing calcitonin with other commonly used analgesics are needed to more clearly define its place in therapy.

Meta-analyses of therapies for postmenopausal osteoporosis. VI. Meta-analysis of calcitonin for the treatment of postmenopausal osteoporosis

OBJECTIVE

To review the effect of calcitonin on bone density and fractures in postmenopausal women.

DATA SOURCE

We searched MEDLINE and EMBASE from 1966 to 2000 and examined citations of relevant articles and the proceedings of international osteoporosis meetings. We contacted osteoporosis investigators to identify additional studies and primary authors for unpublished data.

STUDY SELECTION

We included 30 studies that randomized women to calcitonin or an alternative (placebo or calcium and/or vitamin D) and measured bone density or fracture incidence for at least 1 yr.

DATA EXTRACTION

For each trial, three independent reviewers assessed the methodological quality and abstracted data.

DATA SYNTHESIS

Calcitonin reduced the incidence of vertebral fractures, with a pooled relative risk (RR) of 0.46 [95% confidence interval (CI) 0.25-0.87, P = 0.02, n = 1404, 4 trials]. However, the RR from the one relatively large randomized controlled trial (RCT) was 0.79 (95% CI 0.62-1.00, P = 0.05, n = 1108). For nonvertebral fractures, the pooled RR was 0.52 (95% CI 0.22-1.23, P = 0.14, n = 1481, 3 trials). Once again, the single large trial showed a less impressive effect than the smaller trials (RR 0.80, 95% CI 0.59-1.09, P = 0.16, n = 1245). For bone density of the lumbar spine, the pooled weekly dose of 250 to 2800 IU per week resulted in significant increase in the weighted mean difference (WMD) of 3.74 (2.04-5.43, P < 0.01, n = 2260, 24 trials). The combined forearm showed a similar effect, with a WMD of 3.02 (95% CI 0.98-5.07, P < 0.01, n = 468, 9 trials). At the femoral neck, the pooled weighted mean difference showed a nonsignificant trend toward benefit, WMD 3.80 (95% CI -0.32-7.91, P = 0.07, 9 trials, n = 513). Methodologically weaker studies tended to show greater effects on bone density, and the lumbar spine results suggested the possibility of publication bias.

CONCLUSIONS

Calcitonin likely increases bone density in postmenopausal women predominantly at the lumbar spine and forearm for weekly doses of greater than 250 IU, although the true effect may be smaller than the pooled estimate would suggest. Calcitonin likely reduces the risk of vertebral fracture; its effect on nonvertebral fracture remains uncertain.

Pyrazolopyrimidine-2,4-dione sulfonamides: novel and selective calcitonin inducers

A series of pyrazolo[4,3-d]pyrimidine sulfonamides and pyrazolo[3,4-d]pyrimidine sulfonamides have been synthesized. These compounds increase transcription of a calcitonin-luciferase promoter and production of cellular calcitonin in a calcitonin-secretion/RIA assay with minimized phosphodiesterase type 4 inhibitory activity at 30 microM as compared to structurally related xanthine methylene ketones such as denbufyllene. These two series are notable examples of small molecules that act as CT-inducers, a method to potentially treat bone loss diseases.

Comparative safety of bone remodeling agents with a focus on osteoporosis therapies

This article reviews the different treatments currently available for osteoporosis and examines the benefits and adverse events that are associated with each. While emphasizing safety considerations, this review summarizes the following treatments for osteoporosis: calcium supplements, fluoride, hormone replacement therapy, raloxifene, bisphosphonates, salmon calcitonin, and calcitriol. Before prescribing any of these agents, the clinician should review the risk/benefit profile of each drug in the context of the individual patient's history, concomitant diseases, concurrent medications, and general physical condition.

Osteoporosis therapies for rheumatoid arthritis patients: minimizing gastrointestinal side effects

OBJECTIVE

This manuscript identifies characteristics that put people with rheumatoid arthritis (RA) at high risk for osteoporosis or gastrointestinal (GI) disturbances. The manuscript then reviews therapies available for osteoporosis in the United States and makes recommendations about choosing therapies that minimize GI adverse effects in RA patients at high risk for such events.

DATA SOURCES

References identified through MEDLINE, abstracts, and prescribing information for individual drugs.

DATA EXTRACTION

Characteristics that predispose patients to osteoporosis and GI problems were identified. Data on individual osteoporosis therapies were assessed by risk-benefit analysis and appropriateness for use in patients at risk for GI disturbances.

DATA SYNTHESIS

High risk of osteoporosis in people with RA is caused by disease activity, medication effects, physical inactivity, and standard risk factors such as postmenopausal status and increased age. Patients with RA are frequently at high GI risk if they are receiving nonsteroidal anti-inflammatory drugs or corticosteroids. Because of the high potential for erosive esophagitis and other upper GI disorders with alendronate, caution is warranted in prescribing alendronate to RA patients with high GI risk. In such patients, estrogen replacement therapy, selective estrogen receptor modulators, or calcitonin should be considered for treatment, and either estrogen replacement therapy or selective estrogen receptor modulators should be considered for osteoporosis prevention.

CONCLUSIONS

Assessment of GI risk is important in patients with RA and osteoporosis. Risk factors should be considered when choosing osteoporosis therapies.

Oral delivery of salmon calcitonin

Calcitonin plays a crucial role in both calcium homeostasis and bone remodeling. Establishing an oral delivery system for CT is of great importance since CT is currently administered only parenterally or nasally. Poor absorption and rapid proteolytic degradation have impeded the clinical development of an orally administered sCT drug product. Potential approaches to enhance sCT absorption include the use of formulation additives in the drug product to transiently modulate the intestinal environment or targeting specific intestinal regions that may have favorable peptide delivery properties (e.g., low residual volume, high absorptive surface area or reduced enzymatic activity). Potential approaches to limit the activity of intestinal enzymes include adjusting the pH of the intestinal contents to the pH minima of specific enzymes or maintaining high local drug concentrations in order to saturate enzyme systems. In this review, pharmacokinetic studies elucidating the rate-limiting steps for achieving adequate sCT oral bioavailability are detailed. Further, several approaches for enhancing the oral absorption of sCT are presented. Specific emphasis is placed on regio-specific targeting (e.g., intestinal regional differences in dilution and spreading, etc.) and modulation of the intestinal environment (e.g., changing pH, etc.). The approaches are evaluated in in vitro and in vivo models. Finally, this paper closes with a brief section of concluding remarks.

Raloxifene: a review of its use in postmenopausal osteoporosis

Raloxifene is a selective estrogen receptor modulator that partially mimics the effects of estrogens in bone and the cardiovascular system, while functioning as an antiestrogen in endometrial and breast tissue. In randomised placebo-controlled studies involving postmenopausal women or patients with osteoporosis, raloxifene 60 to 150 mg/day was effective in increasing bone mineral density (BMD) over 12- to 36-month periods. At the 60 mg/day recommended dosage, increases of 1.6 to 3.4%, 0.9 to 2.3% and 1.0 to 1.6% were reported in lumbar spine, femoral neck and total hip, respectively, versus < or =0.5% with placebo. Raloxifene 60 or 120 mg/day decreased the risk of vertebral fractures over a 36-month period in postmenopausal patients with osteoporosis. Significant reductions in radiographic fracture risk versus placebo (30 and 50%) occurred regardless of whether patients had existing fractures at baseline. Although raloxifene did not affect the overall incidence of nonvertebral fractures, a reduction in the incidence of ankle fracture was reported in comparison with placebo. In postmenopausal women, raloxifene 60 mg/day significantly reduced serum levels of total and low density lipoprotein cholesterol from baseline, compared with placebo. High density lipoprotein cholesterol and triglyceride levels were unaffected. Raloxifene 60 or 120 mg/day reduced the risk of invasive breast cancer by 76% during a median of 40 months' follow-up in postmenopausal patients with osteoporosis and no history of breast cancer. A relative risk reduction of 90% was reported for estrogen-receptor positive invasive breast cancers; estrogen-receptor negative cancer risk was unaffected by raloxifene. Raloxifene was generally well tolerated in clinical trials at dosages up to 150 mg/day. Adverse events thought to be related to raloxifene treatment were hot flushes and leg cramps. Venous thromboembolism was the only serious adverse event thought to be related to raloxifene treatment and a relative risk of 3.1 compared with placebo treatment was reported in patients with osteoporosis. Vaginal bleeding occurred in < or =6.4% of raloxifene-treated women but was reported by 50 to 88% of those receiving estrogens or hormone replacement therapy (HRT). Raloxifene treatment was not associated with stimulatory effects on the endometrium.

CONCLUSIONS

Raloxifene significantly increases BMD in postmenopausal women and reduces vertebral fracture risk in patients with osteoporosis. In clinical trials, raloxifene was generally well tolerated compared with placebo and HRT, although its propensity to cause hot flushes precludes use in women with vasomotor symptoms. In particular, the lack of stimulatory effects on the endometrium and the reduction in invasive breast cancer incidence indicate raloxifene as an attractive alternative to HRT for the management of postmenopausal osteonorosis.

Novel and selective calcitonin-inducing agents

A series of xanthine sulfonamides is presented as a class of calcitonin (CT) inducers - a potentially new method for treating diseases associated with postmenopausal bone loss such as osteoporosis. We have found that certain di-n-butylxanthine sulfonamides 4 upregulate CT transcription in a CT-luciferase reporter gene assay (CT-luci) and increase the production and release of CT in a CT secretion/RIA assay (CTS). In addition, these compounds do not have potent PDE4 inhibitory activity as do the related xanthine methylene ketones such as denbufyllene (2). One compound in particular (9) shows a transcription activation ratio (TAR) of 2.1 in CT-luci, a CTS increase of 3.6-fold, and a PDE4 (phosphodiesterase type IV) IC(50) = 4.1 microM. In addition, this compound showed a statistically significant 47% trabecular bone protection in ovariectomized-induced osteopenia (OVX) rats as determined by assay when administered for 4 weeks at 30 mg/kg/day, i. p. by quantitative computed tomography (QCT). When administered p.o., compound 9 shows 50% trabecular bone protection when administered for 3 weeks at 50 mg/kg/day, i.p. This compared with salmon CT which shows 62% trabecular bone protection when administered at 50 IU/kg/day for 4 weeks.

Diagnosis and treatment of nonsteroidal anti-inflammatory drug-associated upper gastrointestinal toxicity

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely prescribed in the United States to treat pain and reduce inflammation from chronic inflammatory disorders such as rheumatoid arthritis and osteoarthritis. Approximately 40% of older Americans take NSAIDs. Chronic NSAID use carries a risk of peptic ulcer and other gastrointestinal disturbances. This article reviews the diagnosis of medication-induced ulcers based on clinical presentation, laboratory tests, and endoscopic findings to assist the clinician in early diagnosis and appropriate therapy. Risk factors for NSAID-induced ulcers include old age, poor medical status, prior ulcer, alcoholism, smoking, high NSAID dosage, prolonged NSAID use, and concomitant use of other drugs that are gastric irritants, such as alendronate, a bone resorption inhibitor prescribed for osteoporosis. Appropriate treatment options for patients with medication-induced ulcers include dosage reduction, medication substitution, medication withdrawal, antiulcer therapy, and discontinuation of other gastrotoxic drugs.

Effect of calcitonin on bone and connective tissue metabolism in hemiplegic patients: a two-year prospective study

OBJECTIVES

To test the effects of 200 IU/day of a nasal spray of salmon calcitonin in modulating the increased bone tissue metabolism observed in hemiplegic patients.

DESIGN

A two-year, prospective, randomized, double-blind, placebo-controlled study.

PATIENTS

Thirty-four patients with hemiplegia due to a cerebrovascular accident were included in the study during the first month after onset of hemiplegia after giving their informed consent. All patients followed a suitably planned course of active rehabilitation according to Bobath. They were randomly allocated to either the calcitonin or the placebo group but all of them received a daily oral calcium supplementation of 1000 mg.

RESULTS

Biochemical markers of bone formation, serum total alkaline phosphatase, osteocalcin and type I procollagen did not vary during the two years of follow-up. Cross-linked carboxy-terminal telopeptide of type I collagen, a biochemical marker of bone resorption, was elevated initially after stroke and then decreased significantly (p <0.001), stabilizing as of month 12. Urinary calcium/creatinine and total hydroxyproline/creatinine ratios presented with similar profiles. The serum levels of the type III procollagen, a marker of connective tissue metabolism, were also elevated upon entry and decreased thereafter. No significant difference could be found between the calcitonin-treated and the placebo group for any of the biochemical markers at any time point.

CONCLUSION

This prospective study demonstrated that biochemical markers of bone and connective tissue metabolism were elevated shortly after the occurrence of stroke and then gradually decreased during the first two years after injury. The daily administration of 200 IU of intranasal calcitonin did not influence the levels of these markers.

Human Anti-Animal Antibody Interferences in Immunological Assays

Purpose: The scope and significance of human anti-animal antibody interference in immunological assays is reviewed with an emphasis on human anti-animal immunoglobulins, particularly human anti-mouse antibodies (HAMAs).

Issues: Anti-animal antibodies (IgG, IgA, IgM, IgE class, anti-isotype, and anti-idiotype specificity) arise as a result of iatrogenic and noniatrogenic causes and include human anti-mouse, -rabbit, -goat, -sheep, -cow, -pig, -rat, and -horse antibodies and antibodies with mixed specificity. Circulating antibodies can reach gram per liter concentrations and may persist for years. Prevalence estimates for anti-animal antibodies in the general population vary widely and range from &lt;1% to 80%. Human anti-animal antibodies cause interferences in immunological assays. The most common human anti-animal antibody interferent is HAMA, which causes both positive and negative interferences in two-site mouse monoclonal antibody-based assays. Strategies to prevent the development of human anti-animal antibody responses include immunosuppressant therapy and the use of humanized, polyethylene glycolylated, or Fab fragments of antibody agents. Sample pretreatment or assay redesign can eliminate immunoassay interferences caused by anti-animal antibodies. Enzyme immunoassays, immunoradiometric assays, immunofluorescence, and HPLC assays have been designed to detect HAMA and other anti-animal antibodies, but intermethod comparability is complicated by differences in assay specificity and lack of standardization.

Conclusions: Human anti-animal antibodies often go unnoticed, to the detriment of patient care. A heightened awareness on the part of laboratory staff and clinicians of the problems caused by this type of interference in routine immunoassay tests is desirable. Efforts should be directed at improving methods for identifying and eliminating this type of analytical interference.

Effect of salmon-calcitonin on the analgesic effect of selective mu, delta and kappa opioid agonists in mice

The analgesic effect of three different opioid agonists, DAMGO ([D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin), U-50,488H (trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidynyl)cyclohexyl] benzene-aceramide methane sulphonate), and [D,Pen2-D,Pen5]-enkephalin, which act upon mu, delta and kappa opioid receptors, respectively, was compared in the presence and absence of salmon-calcitonin (s-CT). The analgesic test used was the writhing test in mice. The analgesic effect of the opioids was significantly enhanced by pretreatment of the animals with s-CT intraperitoneally (i.p.) administered. This effect was more evident for the delta and kappa-agonists. The present result suggests that the joint administration of s-CT and opioids may be a useful and interesting alternative in the treatment of painful diseases resistant to other treatments.