A randomised controlled trial with prolonged-release oral oxycodone and naloxone to prevent and reverse opioid-induced constipation

BACKGROUND

Opioid-induced constipation can have a major negative impact on patients' quality of life. This randomised, double-blinded study evaluated the analgesic efficacy of prolonged-release (PR) oral oxycodone when co-administered with PR oral naloxone, and its impact on opioid-induced constipation in patients with severe chronic pain. Another objective was to identify the optimal dose ratio of oxycodone and naloxone.

METHODS

A total of 202 patients with chronic pain (mainly non-cancer related, 2.5% of patients had cancer-related pain) under stable oral oxycodone therapy (40, 60 or 80 mg/day) were randomised to receive 10, 20, 40 mg/day naloxone or placebo. After a 4-week maintenance phase, patients received oxycodone only for 2 weeks. Pain intensity was evaluated using a numerical analogue scale and bowel function was assessed using the bowel function index.

RESULTS

No loss of analgesic efficacy with naloxone was observed. Mean pain intensity scores on randomisation were comparable for placebo, 10mg, 20mg and 40 mg naloxone dose, and remained unchanged during treatment. Bowel function improved with increasing naloxone dose. Naloxone 20mg and 40 mg significantly improved bowel function at the end of the maintenance phase compared with placebo (p<0.05). Overall, the combination was well tolerated, with no unexpected adverse events. There was a trend towards an increased incidence of diarrhoea with higher doses of naloxone. The 2:1 oxycodone/naloxone ratio was identified as the most suitable for further development.

CONCLUSION

Co-administration of PR oral naloxone and PR oral oxycodone is associated with a significant improvement in bowel function compared with PR oral oxycodone alone, with no reduction in the analgesic efficacy of oxycodone.

Fixed-ratio combination oxycodone/naloxone compared with oxycodone alone for the relief of opioid-induced constipation in moderate-to-severe noncancer pain

OBJECTIVE

Opioid therapy is frequently associated with treatment-limiting constipation. Naloxone is an opioid antagonist with low oral systemic bioavailability. This Phase III clinical trial assessed the safety and efficacy of an oral fixed-ratio combination of oxycodone prolonged-release (PR) and naloxone PR compared with oxycodone PR in relieving opioid-induced constipation.

STUDY DESIGN

This double-blind, multicenter trial was conducted in specialist and primary care centers in four European countries in an out-patients setting. The study included 322 adult patients with moderate-to-severe, noncancer pain requiring opioid therapy in a range of >or=20 mg/day and <or=50 mg/day oxycodone. Following a run-in phase patients were randomized to receive oxycodone PR/naloxone PR or oxycodone PR for 12 weeks. The primary outcome was improvement in constipation as measured using the Bowel Function Index (BFI). Secondary/exploratory assessments focused on pain intensity and additional bowel parameters.

TRIAL REGISTRATION

NCT00412152.

RESULTS

A significant improvement in BFI scores occurred with oxycodone PR/naloxone PR compared with oxycodone PR after 4 weeks of double-blind treatment (-26.9 vs. -9.4, respectively; p < 0.0001), observed after only 1 week of treatment and continued until study end. A significant increase in the number of complete spontaneous bowel movements and decrease in laxative use were also reported. This improvement in bowel function was achieved without compromising the analgesic efficacy of the oxycodone component; pain intensity remained constant throughout the study. The incidence of adverse events was comparable in both groups and consistent with those expected of opioid analgesics. As the study was limited to a dose range of up to 50 mg oxycodone equivalent per day, further research on higher doses would be recommended.

CONCLUSION

The fixed-ratio combination of oxycodone PR/naloxone PR is superior to oxycodone PR alone, offering patients effective analgesia while significantly improving opioid-induced constipation.

Combined prolonged-release oxycodone and naloxone improves bowel function in patients receiving opioids for moderate-to-severe non-malignant chronic pain: a randomised controlled trial

BACKGROUND

This randomised, double-blind, double-dummy, parallel-group multicentre study assessed the impact of a total daily dose of 60-80 mg oral oxycodone prolonged-release (PR)/naloxone PR (OXN PR) as fixed-ratio combination for patients with opioid-induced constipation (OIC) having moderate-to-severe, non-malignant pain.

METHODS

During pre-randomisation patients receiving opioids for moderate-to-severe non-malignant pain were converted to oxycodone PR (OXY PR) and titrated to an effective analgesic dose. During randomisation 265 patients on a stable OXY PR dose (60-80 mg/day) and with OIC were included in the full analysis population to receive OXN PR or OXY PR alone. Primary outcome was improvement in symptoms of constipation as measured by the Bowel Function Index (BFI). Secondary/exploratory outcomes examined analgesic efficacy and other bowel function parameters.

RESULTS

After 4 weeks of treatment, patients receiving OXN PR showed a significant improvement in bowel function compared with those in the OXY PR group (-14.9; 95% CI: -17.9, -11.9; p<0.0001) as measured by BFI which was seen after only 1 week of treatment continuing to the end of the study. After 4 weeks of treatment, patients receiving OXN PR had a median number of 3.0 complete spontaneous bowel movements (CSBM) per week compared with only 1.0 for OXY PR alone. Laxative intake was lower in the OXN PR than the OXY PR group. Furthermore, improvements in bowel function were achieved without loss of analgesic efficacy; pain intensity scores were comparable between the groups and consistent for duration of the study. Most frequently reported adverse events were consistent with those reported for opioid analgesics; no new or unexpected adverse reactions attributable to OXN PR used in higher doses were observed.

CONCLUSION

This study shows that the fixed-ratio combination of OXN PR is superior to OXY PR alone in terms of bowel function, while providing effective equivalent analgesia.

A randomized, double-blind, active-controlled, double-dummy, parallel-group study to determine the safety and efficacy of oxycodone/naloxone prolonged-release tablets in patients with moderate/severe, chronic cancer pain

OBJECTIVE

An examination of whether oxycodone/naloxone prolonged-release tablets (OXN PR) can improve constipation and maintain analgesia, compared with oxycodone prolonged-release tablets (OxyPR) in patients with moderate/severe cancer pain.

METHODS

Randomized, double-blind, active-controlled, double-dummy, parallel-group study in which 185 patients were randomized to receive up to 120 mg/day of OXN PR or OxyPR over 4 weeks. Efficacy assessments included Bowel Function Index (BFI), Brief Pain Inventory Short-Form (BPI-SF), laxative and rescue medication use. Quality of life (QoL) and safety assessments were conducted.

RESULTS

After 4 weeks, mean BFI score was significantly lower with OXN PR; mean total laxative intake was 20% lower with OXN PR. Mean BPI-SF scores were similar for both treatments and the average rate of analgesic rescue medication use was low and comparable. QoL assessments were stable and comparable with greater improvements in constipation-specific QoL assessments with OXN PR. Overall, rates of adverse drug reactions were similar.

CONCLUSIONS

OXN PR provides superior bowel function in cancer pain patients, compared with OxyPR, without compromising analgesic efficacy or safety. This study confirms that OXN PR is well tolerated and efficacious in cancer pain patients and results are in line with those seen in non-malignant pain patients.

Long-term efficacy and safety of combined prolonged-release oxycodone and naloxone in the management of non-cancer chronic pain

OBJECTIVE

The aim of this study was to assess safety and efficacy of fixed combination oxycodone prolonged release (PR)/naloxone PR in terms of both analgesia and improving opioid-induced bowel dysfunction (OIBD) and associated symptoms, such as opioid-induced constipation (OIC), in adults with chronic non-cancer pain.

STUDY DESIGN

These were open-label extension studies in which patients who had previously completed a 12-week, double-blind study received oxycodone PR/naloxone PR for up to 52 weeks. The analgesia study assessed pain using the modified Brief Pain Inventory-Short Form (BPI-SF). The bowel function study assessed improvements in constipation using the Bowel Function Index (BFI).

RESULTS

At open-label baseline in the analgesia study (n = 379), mean score [+/- standard deviation (SD)] for the BPI-SF item 'average pain over the last 24 h' was 3.9 +/- 1.52, and this remained low at 6 months (3.7 +/- 1.59) and 12 months (3.8 +/- 1.72). Mean scores for BPI-SF item 'sleep interference', and the BPI-SF 'pain' and 'interference with activities' subscales also remained low throughout the 52-week study. In the bowel function study (n = 258), mean BFI score (+/- SD) decreased from 35.6 +/- 27.74 at the start of the extension study to 20.6 +/- 24.01 after 12 months of treatment with oxycodone PR/naloxone PR. Pain scores also remained low and stable during this study. Adverse events in both extension phases were consistent with those associated with opioid therapy; no additional safety concerns were observed.

CONCLUSION

Results from these two open-label extension studies demonstrate the long-term efficacy and tolerability of fixed combination oxycodone PR/naloxone PR in the treatment of chronic pain. Patients experienced clinically relevant improvements in OIBD while receiving effective analgesic therapy.

Candida africana sp. nov., a new human pathogen or a variant of Candida albicans?

Atypical Candida strains were isolated from patients in Madagascar, Angola and Germany. These isolates were slow growing and were unable to produce chlamydospores. They had atypical carbohydrate assimilation profiles. All strains were unable to assimilate the amino sugars N-acteylglucosamine and glucosamine as well as the disaccharide trehalose and the organic acid DL-lactate. They were germ-tube-positive in serum, but only some of these organisms produced pseudohyphae after a long incubation. As shown by Fourier transform infrared spectroscopy the atypical Candida isolates clustered as a monophyletic group different from C. albicans and C. dubliniensis. All strains belonged to C. albicans serotype B. Considering all data presented here, this group of Candida strains differs from any other known member of the genus Candida. Therefore, it is suggested to represent a new species within the genus Candida for which the name Candida africana is proposed.

Opioid-induced bowel dysfunction in cancer-related pain: causes, consequences, and a novel approach for its management

Opioids are the mainstay of management for patients with cancer-related pain. Although the analgesic efficacy of opioid therapy is well documented, the recent European Pain in Cancer survey demonstrated that the management of moderate-to-severe pain in patients with cancer is far from optimal. Bowel dysfunction, and importantly constipation, is a common side effect and has a significant impact on the patient's morbidity and quality of life. Nonpharmacological strategies and laxatives are often not effective in the management of opioid-induced constipation (OIC), making it necessary to search for new strategies for the treatment of opioid-induced bowel dysfunction. One promising strategy is the prevention of OIC with peripherally acting opioid antagonists that specifically target the underlying cause of this condition, without affecting centrally mediated analgesia. In recent studies, the novel combination of prolonged-release oral oxycodone and prolonged-release oral naloxone provided effective analgesia with improved bowel function in patients suffering from severe cancer-related and noncancer-related pain. The combination has the potential to improve the quality of pain management significantly in these patients.

Fibroblast growth on surface-modified dental implants: an in vitro study

A major consideration in designing dental implants is the creation of a surface that provides strong attachment between the implant and bone, connective tissue, or epithelium. In addition, it is important to inhibit the adherence of oral bacteria on titanium surfaces exposed to the oral cavity to maintain plaque-free implants. Previous in vitro studies have shown that titanium implant surfaces coated with titanium nitride (TiN) reduced bacterial colonization compared to other clinically used implant surfaces. The aim of the present study was to examine the support of fibroblast growth by a TiN surface that has antimicrobial characteristics. Mouse fibroblasts were cultured on smooth titanium discs that were either magnetron-sputtered with a thin layer of titanium nitride, thermal oxidized, or modified with laser radiation (using a Nd-YAG laser). The resulting surface topography was examined by scanning electron microscopy (SEM), and surface roughness was estimated using a two-dimensional contact stylus profilometer. A protein assay (BCA assay) and a colorimetric assay to examine fibroblast metabolism (MTT) were used. Cellular morphology and cell spreading were analyzed using SEM and fluorescence microscopy. Fibroblasts on oxidized titanium surfaces showed a more spherical shape, whereas cells on laser-treated titanium and on TiN appeared intimately adherent to the surface. The MTT activity and total protein were significantly increased in fibroblasts cultured on titanium surfaces coated with TiN compared to all other surface modifications tested. This study suggests that a titanium nitride coating might be suitable to support tissue growth on implant surfaces.

Efficacy and safety of combined prolonged-release oxycodone and naloxone in the management of moderate/severe chronic non-malignant pain: results of a prospectively designed pooled analysis of two randomised, double-blind clinical trials

BACKGROUND

Two randomised 12-week, double-blind, parallel-group, multicenter studies comparing oxycodone PR/naloxone PR and oxycodone PR alone on symptoms of opioid-induced bowel dysfunction in patients with moderate/severe non-malignant pain have been conducted.

METHODS

These studies were prospectively designed to be pooled and the primary outcome measure of the pooled data analysis was to demonstrate non-inferiority in 12-week analgesic efficacy of oxycodone PR/naloxone PR versus oxycodone PR alone. Patients with opioid-induced constipation were switched to oxycodone PR and then randomised to fixed doses of oxycodone PR/naloxone PR (n = 292) or oxycodone PR (n = 295) for 12 weeks (20-80 mg/day).

RESULTS

No statistically significant differences in analgesic efficacy were observed for the two treatments (p = 0.3197; non-inferiority p < 0.0001; 95% CI -0.07, 0.23) and there was no statistically significant difference in frequency of analgesic rescue medication use. Improvements in Bowel Function Index score were observed for oxycodone PR/naloxone PR by Week 1 and at every subsequent time point (-15.1; p < 0.0001; 95% CI -17.3, -13.0). AE incidence was similar for both groups (61.0% and 57.3% of patients with oxycodone PR/naloxone PR and oxycodone PR alone, respectively).

CONCLUSIONS

Results of this pooled analysis confirm that oxycodone PR/naloxone PR provides effective analgesia and suggest that oxycodone PR/naloxone PR improves bowel function without compromising analgesic efficacy.

TRIAL REGISTRATION NUMBERS

ClinicalTrials.gov identifier: NCT00412100 and NCT00412152.

Membranes for biohybrid liver support systems--investigations on hepatocyte attachment, morphology and growth

The biological properties of four different membranes were studied regarding their possible application in biohybrid liver support systems. Two of them, one made of polyetherimide (PEI), and a second based on polyacrylonitrile-N-vinylpyrollidone co-polymer (P(AN-NVP)), were recently developed in our lab and studied for the first time. Together with pure polyacrylonitrile (PAN) membranes, the three preparations were characterised as ultra-filtration membranes. Their ability to support cell attachment, morphology, proliferation and function of human hepatoblastoma C3A cells was studied. The role of surface morphology for the interaction with hepatocytes was highlighted using a commercial, moderately wettable polyvinylidendifluoride (PVDF) membrane with micro-filtration properties. Comparative investigations showed strongest interaction of C3A cells with PAN membranes, as the focal adhesion contacts were more expressed and cell growth was also high. However, the functional activity in terms of albumin synthesis was reduced. Very similar results were obtained with the most hydrophobic PEI membrane. In contrast, the most hydrophilic membrane P(AN-NVP) was found to provoke stronger homotypic adhesion (E-cadherin expression) of C3A cells and less substratum attachment (focal adhesions), but enhanced albumin secretion. However, proliferation of C3A cells was lowered. Micro-porous PVDF membrane showed very good initial attachment, but the resulting cell material and cell-cell interaction were relatively poor developed. Among four membranes tested, PEI seems to be the most attractive membrane for biohybrid liver devices, as it provides good surface properties for hepatocytes interaction, but in addition it is highly thermostable, which would permit steam sterilisation. No simple relationship, however, between the wettability of the membranes and their ability to support hepatocyte adhesion and function was found in this study.

Long-term safety and efficacy of oxycodone/naloxone prolonged-release tablets in patients with moderate-to-severe chronic cancer pain

Aim

To evaluate the long-term safety and efficacy of prolonged-release oxycodone/naloxone (OXN PR) and its impact on quality of life (QoL), in patients with moderate-to-severe cancer pain.

Methods

This was an open-label extension (OLE) of a 4 week, randomized, double-blind (DB) study in which patients with moderate-to-severe cancer pain had been randomized to OXN PR or oxycodone PR (OxyPR). During the OLE phase, patients were treated with OXN PR capsules (≤20/60 mg/day) for ≤24 weeks. Outcome measures included safety, efficacy and QoL.

Results

One hundred and twenty-eight patients entered the OLE, average pain scores based on the modified Brief Pain Inventory—Short Form were low and stable over the 24-week period. The improvement in bowel function and constipation symptoms as measured by the Bowel Function Index and patient assessment of constipation in patients treated with OXN PR during the 4-week DB study was maintained. In patients treated with OxyPR during the DB phase, bowel function and constipation symptoms were improved during the OLE. In the DB and in the OLE, health status and QoL were similar for patients treated with OXN PR and OxyPR. There were no unexpected safety or tolerability issues.

Conclusions

In patients with moderate-to-severe cancer pain, long-term use of OXN PR is well tolerated and effective, resulting in sustained analgesia, improved bowel function and improved symptoms of constipation.

Observational, nonintervention, multicenter study for validation of the Bowel Function Index for constipation in European countries

OBJECTIVE

Constipation is a common adverse event of treatment with opioids for chronic non-malignant pain and may result in a considerable reduction in health-related quality of life. The aim of this study was to assess the psychometric properties of the Bowel Function Index (BFI) in european patients suffering from constipation secondary to opioid analgesic treatment for chronic, non-malignant pain.

METHODS

This was a multinational study conducted at 15 clinical sites in the Czech Republic, Germany, Italy, and the United Kingdom. Patients suffering from constipation secondary to opioid analgesic treatment for chronic, non-malignant pain were recruited to complete a series of questionnaires including a socio-demographic form, the BFI, the Patient Assessment of Constipation - Symptoms (PAC-SYM), a global frequency item, and a clinical form.

RESULTS

A total of 131 patients were included in this study. Inter-item correlations of the BFI were statistically significant in the moderate to large range and the analysis indicated a strong degree of internal consistency (Cronbach's alpha = 0.86). All correlations between the BFI and the global item were statistically significant in the moderate to high range (r = 0.59 to 0.69; p < 0.0001). Correlations between the BFI and the PAC-SYM were moderate and statistically significant (p < 0.01 to 0.0001).

CONCLUSIONS

Although this study was limited by the relatively small sample size, it is a part of an extensive validation program. This study suggests that the BFI is a reliable and valid measure of constipation-related symptomatology in chronic pain patients. This measure may be a valuable indicator of patients' experience of symptoms of opioid treatment of chronic pain in future trials.

Patient assessment of a novel therapeutic approach for the treatment of severe, chronic pain

BACKGROUND AND OBJECTIVES

Opioid-induced constipation can have a major negative impact on patients' quality of life. This randomised clinical trial evaluated patient assessment of the efficacy and tolerability of oral prolonged-release (PR) oxycodone when co-administered with oral naloxone PR.

METHODS

Two hundred and two patients with chronic cancer- or non-cancer-related pain undergoing stable oxycodone PR therapy (40, 60 or 80 mg/day) were randomised to one of four intervention groups: 10, 20 or 40 mg/day naloxone PR or placebo. Following a 4-week maintenance phase, patients were followed-up for 2 weeks in which time they received oxycodone PR only. At the end of the maintenance phase, patients and investigators were asked to assess treatment efficacy and tolerability, as well as preference for the titration or maintenance phase.

RESULTS

Patient and investigator global assessment of efficacy and tolerability improved with increasing naloxone dose. Efficacy was ranked as 'good' or 'very good' by 50.0%, 67.4% and 72.5% of patients in the 10, 20 and 40 mg naloxone PR dose groups, respectively, compared with 43.5% of patients in the placebo group. Patient assessment of tolerability was similar between treatment groups and placebo, being ranked as 'good' or 'very good' by 83.3%, 79.1% and 82.5% of patients in the 10, 20 and 40 mg/day naloxone PR dose groups, respectively, compared with 71.7% of patients in the placebo group. The maintenance treatment phase was preferred by patients in the naloxone groups. A 2 : 1 dose ratio of oxycodone to naloxone was also assessed. Efficacy was ranked as 'good' or 'very good' by 70.4% of patients treated with the 2 : 1 dose ratio compared with 43.5% of patients receiving placebo. Tolerability of the 2 : 1 dose ratio was ranked as being 'good' or 'very good' by 81.5% of patients compared with 71.1% for the placebo group and patients preferred the maintenance phase.

CONCLUSIONS

The co-administration of oral naloxone PR with oxycodone PR improves patient assessment of analgesic opioid therapy for severe chronic pain, in terms of both efficacy and tolerability.

Naloxone as part of a prolonged release oxycodone/naloxone combination reduces oxycodone-induced slowing of gastrointestinal transit in healthy volunteers

OBJECTIVES

This exploratory study in healthy volunteers investigated the effect of single doses of oxycodone on gastrointestinal (GI) transit time and the degree to which a single dose of naloxone reverses the oxycodone-induced effect.

METHODS

Fifteen healthy male volunteers received: oxycodone 10 and2 0 mg, oxycodone/naloxone 10/5 and 20/10 mg (all as prolonged release tablets) and placebo. Each dose was radiolabelled and administered with a capsule containing radiolabelled resin (surrogate for GI contents).

RESULTS

Scintigraphic analysis showed that 20 mg oxycodone significantly increased colon arrival time (mean 7.19 vs 5.15 h for placebo, p = 0.0159). Mean colon arrival time for oxycodone/naloxone 20/10 mg (5.16 h) was similar to placebo, although the difference between oxycodone/naloxone 20/10 mg versus oxycodone 20 mg was not significant (p = 0.0653). Colonic geometric centre analysis showed a significant increase in mean time for the resin to reach the colon following oxycodone 10 and 20 mg compared with placebo (increases of 5.3 and 8.8 h). There was no significant effect of naloxone at the lower dose; however, oxycodone/naloxone 20/10 mg significantly reduced mean colonic transit time by 2.1 h (p = 0.0376).

CONCLUSION

A single dose of oxycodone 20 mg significantly prolonged GI transit time but this effect was reduced by co-administration of naloxone.

A Liposome Hydrogel With Polyvinyl-Pyrrolidone Iodine in the Local Treatment of Partial-Thickness Burn Wounds

Local treatment of burn injuries with conventional anti-infective preparations does not provide the moist environment that promotes fast wound healing. In a randomized controlled trial the effects of liposome polyvinyl-pyrrolidone-iodine (PVP-I) hydrogel, a novel formulation of PVP-I in a liposome hydrogel with high water-binding capacity, were investigated in 43 patients with partial-thickness burn wounds in an intraindividual comparison with a conventional silver-sulfadiazine cream. Treatment with liposome PVP-I hydrogel resulted in significantly faster complete healing of the burn wounds compared with silver-sulfadiazine cream (9.9 +/- 4.5 days versus 11.3 +/- 4.9; P < 0.015). The cosmetic result (smoothness, elasticity, appearance) was rated as excellent for 37.0% of study wounds with liposome PVP-I hydrogel compared with 13.0% of wounds treated with silver-sulfadiazine cream. Local tolerability was good; handling and change of dressing were rated as easy. Local treatment with liposome PVP-I hydrogel thus provides fast wound healing with a favorable cosmetic result.

Long-term evaluation of combined prolonged-release oxycodone and naloxone in patients with moderate-to-severe chronic pain: pooled analysis of extension phases of two Phase III trials

BACKGROUND

While opioids provide effective analgesia, opioid-induced constipation (OIC) can severely impact quality of life and treatment compliance. This pooled analysis evaluated the maintenance of efficacy and safety during long-term treatment with combined oxycodone/naloxone prolonged-release tablets (OXN PR) in adults with moderate-to-severe chronic pain.

METHODS

Patients (N = 474) received open-label OXN PR during 52-week extension phases of two studies, having completed 12-week, double-blind, randomized treatment with oxycodone prolonged-release tablets (Oxy PR) or OXN PR. Analgesia and bowel function were assessed at each study visit using 'Average pain over last 24 h scale and Bowel Function Index (BFI), respectively. Treatment Satisfaction Questionnaire for Medication was assessed at study end only.

KEY RESULTS

Improvement in bowel function was particularly marked in patients who switched from Oxy PR in the double-blind phase to OXN PR during the extension phase, resulting in a clinically meaningful reduction (≥12 points) in BFI score: at the start of the extension phases, mean (SD) BFI score was 44.3 (28.13), and was 29.8 (26.36) for patients who had received OXN PR in the double-blind phase. One week later, BFI scores were similar for the two groups (26.5 [24.40] and 27.5 [25.60], respectively), as was observed throughout the following months. Fewer than 10% of patients received laxatives regularly. Mean 24-h pain scores were low and stable throughout the extension phases. No unexpected adverse events were observed.

CONCLUSIONS & INFERENCES

Pooled data demonstrate OXN PR is an effective long-term therapy for patients with chronic non-cancer pain, and can address symptoms of OIC. No new safety issues were observed which were attributable to the long-term administration of OXN PR.

A phase III randomized controlled study on the efficacy and improved bowel function of prolonged-release (PR) oxycodone-naloxone (up to 160/80 mg daily) vs oxycodone PR

BACKGROUND

Oxycodone/naloxone (OXN PR) is a prolonged-release formulation containing oxycodone and naloxone in a 2:1 ratio. This study aimed to evaluate the tolerability and efficacy of doses up to OXN160/80 mg PR compared with oxycodone prolonged-release formulation (OxyPR) in a randomised controlled trial.

METHODS

Two hundred and forty-three patients were randomised to treatment with OXN PR (n = 123) or OxyPR (n = 120) during the 5-week double-blind study. Measured were: opioid-induced constipation [bowel function index score (BFI)]; analgesic efficacy (NRS 0-10); daily laxative rescue medication use; rescue medication use, and the number of complete spontaneous bowel movements (CSBMs) per week. A subanalysis was conducted in cancer patients.

RESULTS

Greater reductions in mean BFI scores were reported for the OXN PR group compared with OxyPR from Week 1 onwards; at Week 5 the mean change from baseline was -32.5 versus -14.2. Average 24-h pain scores were low and remained stable in the range 3-4 in both treatment groups. Analgesic rescue medication use was similar between the groups. Patients receiving OXN PR used significantly lower mean daily doses of laxative rescue medication than those receiving OxyPR (P = 0.006). The number of CSBM in the OXN PR group approximately doubled compared with a 25% decrease in the OxyPR group. Comparable results to the total study population were reported in the cancer patient subgroup.

CONCLUSIONS

OXN PR in daily doses of up to 160/80 mg significantly improves bowel function compared with equivalent doses of OxyPR while still providing comparable analgesic efficacy.

SIGNIFICANCE

Effective analgesia can be achieved using oxycodone/naloxone PR up to 160/80 mg daily without compromising bowel function. A similar outcome was reported in cancer and non-cancer patients.

Testing the cytotoxicity of metal alloys used as magnetic prosthetic devices

Technical magnetic materials are increasingly used for the development of magnetic retained dental prosthetic and orofacial epithetic devices. Since most of the magnets based on rare earth metals, such as samarium-cobalt based alloys have a high tendency for corrosion they were first coated by tin and then encapsulated by titanium. However, the high mechanical load particularly on dental devices may cause a rupture of the titanium capsule and the alloys contact directly biological fluids. Hence, it is important to know the cytotoxicity of these magnets to assess their potential effects on the surrounding tissue. In this study, the cytotoxicity of neodymium-iron-boron and samarium-cobalt (plain, tin and titanium coated) magnets was tested. First, magnets were incubated up to 7 days in culture medium to prepare extracts for cytotoxicity measurements. Changes in the surface morphology due to corrosion were visualized by scanning electron microscopy and analysis of the elemental composition. 3T3 mouse fibroblasts were cultured in the presence of extracts and their viability measured by neutral red and metabolic assays. To learn more about a possible toxic activity of the main components of magnets, salt solutions of different concentrations resembling those elements, which are main constituents of the magnets, were used. 3T3 fibroblasts were also cultured in direct contact with the materials and material induced effects on cell morphology and growth monitored by microscopy. As a result of this study it was found that samarium-cobalt magnets have a strong tendency for corrosion and exert a considerable cytotoxicity. Neodymium-iron-boron magnets have a lesser tendency for corrosion and are only moderate cytotoxic. Coating of samarium-cobalt magnets with tin or titanium makes the materials non-toxic. Application of salt solutions shows that cobalt has a tendency to be cytotoxic at higher concentrations, but enhances cell metabolism and proliferation at lower concentrations while the other magnet constituents had a lower or negligible cytotoxic potential.

[Prerequisites for effective therapy of chronic recurrent vaginal candidiasis]

67 women with chronic recurrent or persistent vaginal candidosis between 5-79 years of age were seen in our outdoor department. In 34 cases, yeasts could be isolated in a vaginal swab taken at the first consultation. On average the patients reported 5 episodes per year during the last years. Typical symptoms consisted of pruritus vulvae, local inflammation and a curdy vaginal discharge. Nearly all of the women had received local or systemic antimycotic treatment for several times. In 53% (18 patients), C. albicans had been isolated, in 29% (10 patients) C. glabrata and in 9% (3 patients) C. krusei. While candidosis due to C. albicans and C. krusei was frequently associated with distressing complaints, infections with C. glabrata caused only very few symptoms. Independent of the species, severe and persistent infections were characterized by long term persisting specific IgM-antibody-titers and remarkable lack of IgG-antibodies. The laboratory parameters of WBC, CRP and immunelectrophoresis were normal. The minimum inhibitory concentrations (MIC) of 60 Candida strains against fluconacole were determined by microdilution assay. The MIC for C. albicans (n = 35) were between 0.78 and 3.125 micrograms/ml, for C. glabrata (n = 20) between 8 and 32 micrograms/ml and for C. krusei (n = 5) between 25 and 128 micrograms/ml. In 7 cases, local antimycotic treatment was sufficient. Correlating to the sensitivity, 18 women were treated with 100-800 mg fluconacole/d for 10-20 days. In 13 of them, clearance of symptoms and yeasts was achieved. The treatment of fluconacole-resistant strains with itraconazole (100-200 ml/d for 10-20 days) together with local application of nystatin (2 x 1 Mio. IE for 10 days) was without any effect. Three women with C. albicans, C. glabrata and C. krusei infection received a candidin-vaccination (0.005 BE/ml-500 BE/ml). In all of these cases, production of IgM-antibodies was induced. However, the clinical symptoms could not be influenced. Only in two cases it was not possible to reach a clearance of symptoms and yeasts. The results show the benefit of a precise differentiation before therapy. Serologic controls of antibody titers seem to be useful tools to control the efficacy of treatment.

Long-term efficacy and safety of oxycodone-naloxone prolonged-release formulation (up to 180/90 mg daily) - results of the open-label extension phase of a phase III multicenter, multiple-dose, randomized, controlled study

Background

The inclusion of naloxone with oxycodone in a fixed combination prolonged‐release formulation (OXN PR) improves bowel function compared with oxycodone (Oxy) alone without compromising analgesic efficacy. In a recent 5‐week, randomized, double‐blind comparative trial of OXN PR and OxyPR, it could be shown that the beneficial properties of OXN PR extend to doses up to 160/80 mg.

Methods

Bowel function, pain, quality of life (QoL) and safety of OXN PR up to 180/90 mg daily were evaluated in a 24‐week open‐label extension phase of the 5‐week randomized comparative study in patients with non‐malignant or malignant pain requiring opioids and suffering from opioid‐induced constipation.

Results

During treatment with a mean (SD) daily dose OXN PR of 130.7 (26.56) mg (median, maximum: 120 and 180 mg), the Bowel Function Index (BFI) decreased from 45.3 (26.37) to 26.7 (21.37) with the largest decrease seen in the first week. The average pain over the last 24 h remained stable (median Pain Intensity Scale score 4.0) and QoL was maintained throughout the study. Adverse events were consistent with the known effects of OXN PR and no new safety concerns emerged. Equivalent efficacy and safety benefits were observed in cancer patients.

Conclusions

The OXN PR in doses up to 180/90 mg provides effective analgesia with maintenance of bowel function during long‐term treatment. The beneficial effects of such dose levels of OXN PR contribute to stable patient‐reported QoL and health status despite serious underlying pain conditions, such as cancer.

Significance

In patients with pain requiring continuous opioid therapy at doses above 80 mg of oxycodone, stable and effective long‐term analgesia can be achieved using OXN PR up to 180/90 mg daily without compromising bowel function and may be preferential to supplemental oxycodone.

Modified-release prednisone for polymyalgia rheumatica: a multicentre, randomised, active-controlled, double-blind, parallel-group study

Objective

To assess the efficacy and safety of modified-release (MR) versus immediate-release (IR) prednisone in newly diagnosed glucocorticoid (GC)-naïve patients with polymyalgia rheumatica (PMR).

Methods

Patients were randomised to double-blind MR prednisone (taken at approximately 22:00) or IR prednisone (taken in the morning), 15 mg/day for 4 weeks. The primary end point was complete response rate (≥70% reduction in PMR visual analogue scale, duration of morning stiffness and C reactive protein (CRP) (or CRP <2× upper limit of normal (ULN))) at week 4. Non-inferiority was decided if the lower 95% confidence limit (MR vs IR prednisone) was above −15%. 400 patients were planned but only 62 were enrolled due to difficulties in recruiting GC-naïve patients with PMR with CRP ≥2×ULN.

Results

The percentage of complete responders at week 4 was numerically greater for MR prednisone (53.8%) than for IR prednisone (40.9%). Non-inferiority of MR versus IR prednisone was not proven in the primary analysis on the per protocol population (N=48; treatment difference: 12.22%; 95% CI −15.82% to 40.25%). However, sensitivity analysis on the full analysis population showed an evident trend favouring MR prednisone (N=62; treatment difference: 15.56%; 95% CI −9.16% to 40.28%). Adverse events were generally mild and transient with no unexpected safety observations.

Conclusions

The study showed a clear trend for favourable short-term efficacy of MR prednisone versus IR prednisone in early treatment of PMR. Further studies are warranted.

Trial registration number

EudraCT number 2011-002353-57; Results.