Tolerability of diclofenac sodium 1% gel with concomitant medications known to interact with diclofenac.

BACKGROUND: Topical diclofenac sodium 1% gel (DSG) has demonstrated efficacy and tolerability in patients with osteoarthritis (OA) of the knees or hands, including elderly patients and those with an increased risk of gastrointestinal, cardiovascular, and renal adverse events (AEs). Medications known to interact with diclofenac were disallowed in a clinical trial of DSG for knee OA; however, patients were not to be discontinued for intake of disallowed treatment, unless there was a safety issue. This post hoc analysis examined the frequency and type of AEs in patients who received DSG concomitantly with drugs known to have potential interactions with diclofenac. MATERIALS AND METHODS: This was a post hoc analysis of a randomized controlled trial of DSG for knee OA pain. Patients (n = 254) aged ≥ 35 years with OA in one or both knees, but with clinical OA symptoms in only one knee, administered DSG topically to the target knee four times daily (total dose, 16 g/d) for 12 weeks. Drugs with the potential for major or moderate drug-drug interactions (DDIs) were identified via Drugs.com. AE rates were compared in patients with versus those without ≥1 potential DDI. RESULTS: At least one AE was experienced by 62.6% (107/171) of patients with ≥1 DDI and by 55.4% (46/83) of patients with no DDIs. Gastrointestinal AEs (upper and lower) were reported in 5.3% (9/171) and 7.2% (6/83), cardiovascular AEs in 4.7% (8/171) and 1.2% (1/83), renal AEs in 1.2% (2/171) and 0%, and hepatic AEs in 0% and 1.2% (1/83) of patients with ≥1 DDI compared with patients with no DDIs, respectively. CONCLUSION: Concurrent use of DSG with medications that had potential for major to moderate DDIs had little impact on the frequency of AEs in this population. Further research is needed to consider how factors such as dose, duration, and timing of concomitant drug administration may affect the likelihood of clinically evident AEs resulting from a potential DDI.

Long-term tolerability of topical diclofenac sodium 1% gel for osteoarthritis in seniors and patients with comorbidities.

BACKGROUND: Adverse events associated with nonsteroidal anti-inflammatory drugs (NSAIDs) used to treat knee and hand osteoarthritis may be more frequent in certain patient populations. Topical NSAIDs, such as diclofenac sodium 1% gel (DSG), have equivalent efficacy and fewer adverse events compared with oral NSAIDs. This post hoc analysis assessed the long-term tolerability of DSG in elderly patients and patients with an elevated risk of gastrointestinal, cardiovascular, and renal adverse events. METHODS: Patients ≥ 35 years of age with knee osteoarthritis applied DSG (4 g) to one or both knees for 12 weeks during either of two primary studies and for 9 months during a long-term extension study. Other patients entered the long-term extension study directly and applied DSG for 12 months. Safety was assessed by reported adverse events. Subpopulations were defined based on age, or the comorbidities of hypertension, type 2 diabetes mellitus, and cerebrovascular or cardiovascular disease. RESULTS: The safety population consisted of 947 patients who received at least one dose of DSG during the primary or extension study. Patients aged < 65 years (68.2%) and ≥65 years (67.2%) experienced any adverse event at similar rates. The percentage of patients who experienced any adverse event was similar between patients with and without hypertension (65.5% versus 69.7%, respectively), type 2 diabetes mellitus (64.0% versus 68.2%), or cerebrovascular or cardiovascular disease (61.9% versus 68.5%). Among the 15 patients with all three comorbidities, the percentage of patients with any adverse event (53.3%) was less than that of patients who did not have all three comorbidities (68.0%). CONCLUSION: These results suggest that long-term DSG treatment is safe in patient subpopulations with an elevated risk of NSAID-related adverse events, such as the elderly and those with the comorbidities of hypertension, type 2 diabetes mellitus, and cerebrovascular or cardiovascular disease.

Tolerability of concomitant use of selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors and oxymorphone extended release.

BACKGROUND: Opioids and antidepressants are frequently prescribed for chronic low back pain (cLBP). This post hoc analysis was conducted to assess the tolerability of oxymorphone extended release (ER) for cLBP in patients taking selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) compared with patients not taking SSRIs/SNRIs. METHODS: Patients in 2 clinical trials (NCT00225797, November 22, 2004 to July 18, 2005; NCT00226421, October 13, 2004 to August 19, 2005) aged ≥ 18 years with moderate to severe cLBP were titrated to a stabilized dose of oxymorphone ER during an open-label titration phase and then randomized to treatment with this dose or placebo every 12 hours for 12 weeks. In a post hoc analysis, adverse events (AEs) were compared between patients taking versus not taking SSRIs/SNRIs. Treatment efficacy was assessed as change from baseline in average daily pain intensity on a 100-mm visual analog scale. RESULTS: Of 575 patients enrolled, 45 of 89 (50.6%) taking SSRIs/SNRIs and 303 of 486 (62.3%) not taking SSRIs/SNRIs successfully titrated to oxymorphone ER. The frequency of any AE did not differ significantly between the 2 subpopulations. During the titration phase, serious AEs occurred more frequently in patients taking SSRIs/SNRIs (3/89; 3.4%) compared with those not taking SSRIs/SNRIs (4/486; 0.8%; P = 0.04); however, during the double-blind treatment phase, there was no significant difference in the frequency of serious AEs in patients treated with oxymorphone ER taking (1/29; 3.4%) versus those not taking (3/146; 2.0%) SSRIs/SNRIs. Visual analog scale scores were similar in patients taking versus those not taking SSRIs/SNRIs throughout the study. CONCLUSION: The concomitant use of oxymorphone ER with SSRIs or SNRIs was well tolerated in patients with cLBP.

A review of pharmacotherapy for chronic low back pain with considerations for sports medicine.

Up to 30% of athletes experience low back pain (LBP) depending on sport type, sex, training intensity and frequency, and technique. United States clinical guidelines define back pain as chronic if it persists for ≥ 12 weeks, and subacute if it persists 4 to < 12 weeks. Certain sports injuries are likely to lead to chronic pain. Persistent or chronic symptoms are frequently associated with degenerative lumbar disc disease or spondylolytic stress lesions. Exercise therapy is widely used and is the most conservative form of treatment for chronic LBP (cLBP). Pharmacotherapies for cLBP include acetaminophen, nonsteroidal anti-inflammatory drugs, and opioids. Acetaminophen is a well-tolerated first-line pharmacotherapy, but high-dose, long-term use is associated with hepatic toxicity. Nonsteroidal anti-inflammatory drugs can be an effective second-line option if acetaminophen proves inadequate but they have well-known risks of gastrointestinal, cardiovascular, and other systemic adverse effects that increase with patient age, dose amount, and duration of use. The serotonin-norepinephrine reuptake inhibitor, duloxetine, has demonstrated modest efficacy and is associated with systematic adverse events, including serotonin syndrome, which can be dose related or result from interaction with other analgesics. Opioids may be an effective choice for moderate to severe pain but also have significant risks of adverse events and carry a substantial risk of addiction and abuse. Because the course of cLBP may be protracted, patients may require treatment over years or decades, and it is critical that the risk/benefit profiles of pharmacotherapies are closely evaluated to ensure that short- and long-term treatments are optimized for each patient. This article reviews the clinical evidence and the guideline recommendations for pharmacotherapy of cLBP.

An open-label, long-term safety and tolerability trial of diclofenac sodium 1% gel in patients with knee osteoarthritis.

OBJECTIVE: To evaluate the long-term safety and tolerability of topical diclofenac sodium 1% gel (DSG) in the treatment of knee osteoarthritis (OA) for up to 12 months. METHODS: This was a multicenter open-label, extension of two 3-month, randomized, double-blind studies of DSG in patients with knee OA (NCT ID: NCT00171691, "Safety of Diclofenac Sodium Gel in Knee Osteoarthritis"). To ensure adequate enrollment, some DSG-naïve patients with OA who had not participated in the double-blind studies were also enrolled. Patients applied 4 g DSG to 1 or both knees 4 times daily for 9 to 12 months. Safety was evaluated through adverse event (AE) reporting, physical examination, and laboratory investigations. Patients completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, stiffness, and physical function scales every 3 months to assess long-term effectiveness. RESULTS: The extension study enrolled 583 patients; 294 patients completed the study. Use of DSG was documented for 578 patients (safety population). The mean age was 62.3 years, and 63.7% of patients were women. Overall, 112 (19.4%) patients reported ≥ 1 treatment-related AE, and the only treatment-related AE occurring in ≥ 1% of patients was application-site dermatitis. Treatment-related gastrointestinal, renal-function, hepatic-function, and cardiovascular AEs were reported by 3, 1, 2, and 0 patients, respectively. There were no serious AEs or deaths. At 1 year, improvements from baseline for WOMAC pain, stiffness, and physical function scale scores were 39.8%, 33.4%, and 36.9%, respectively. CONCLUSION: The long-term safety profile of DSG was consistent with previous 12-week studies, and DSG remained effective for a 1-year period.

Factors affecting acceptability of titrated oxymorphone extended release in chronic low back pain - an individual patient analysis.

OBJECTIVE: To evaluate the influence of age, sex, and previous opioid experience on the likelihood of successfully titrating opioid-naive and experienced patients with chronic low back pain (CLBP) to an effective and well-tolerated dose of oxymorphone extended release (ER). METHODS: Post hoc analysis of open-label titration phases of two enriched-enrollment randomized-withdrawal phase III trials in 575 adults with moderate-to-severe CLBP. Opioid-naive patients (n = 325) initiated oxymorphone ER at 10 mg/day (5 mg q12 h). Opioid-experienced patients (n = 250) initiated at a dose equianalgesic to their previous opioid and were allowed doses of 5 mg oxymorphone immediate-release rescue medication every 4-6 h, as needed. Oxymorphone ER was gradually titrated to a dose that reduced pain to or=65 years were less likely than patients aged <65 years to complete titration (45 vs. 63%; p = 0.002; 95% CI, -0.30 to -0.06) and more likely to discontinue owing to adverse events (40 vs. 15%; p < 0.001; 95% CI, 0.14-0.36). Oxycodone-experienced patients were less likely than hydrocodone-experienced patients to complete titration (46 vs. 62%, p = 0.03; 95% CI,-0.30 to -0.02). Among successfully titrated patients, pain decreased regardless of prior opioid therapy, sex, or age. CONCLUSIONS: Most patients with CLBP were titrated to an effective, generally well-tolerated oxymorphone ER dose. Older patients and those converted from oxycodone may require more gradual titration. A study limitation is that patients initiated oxymorphone ER to comply with protocol, whereas treatment failure typically motivates opioid initiation or switching in clinical practice.

Correlation of pain relief with physical function in hand osteoarthritis: randomized controlled trial post hoc analysis.

INTRODUCTION: Nonsteroidal anti-inflammatory drugs are recommended for the relief of pain associated with hand osteoarthritis (OA) but do not alter the underlying structural changes that contribute to impaired physical function. The current analysis examined the relationship of pain relief with measures of function and global rating of disease in patients with hand OA. METHODS: This was a combined analysis of 2 prospective, randomized, double-blind, 8-week, multicenter, parallel-group studies comparing diclofenac sodium 1% gel with placebo gel (vehicle) in patients with radiographically confirmed mild to moderate hand OA. Patients (n = 783) aged > or = 40 years applied diclofenac sodium 1% gel (2 g) or vehicle to each hand 4 times daily for 8 weeks. Outcome measures included pain intensity assessed on a 100-mm Visual Analog Scale (VAS); the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) subscales for pain, stiffness, and physical function (100-mm VAS); and a global rating of disease (100-mm VAS). Change in VAS pain intensity from baseline to week 8 was categorized (<0%, 0%-<15%, 15%-<30%, 30%-<50%, 50%-<70%, and > or = 70%) without regard to treatment and compared in each category with the mean change from baseline in each AUSCAN subindex and the global rating of disease. Pearson correlations between changes in outcome measures from baseline to week 8 were calculated. RESULTS: Changes in VAS pain intensity were accompanied by similar changes in AUSCAN scores and global rating of disease. Pearson correlations confirmed significant associations (P < 0.001) between change in VAS pain intensity and changes in AUSCAN pain (correlation coefficient [r] = 0.81), AUSCAN function (r = 0.75), AUSCAN stiffness (r = 0.66), and global rating of disease (r = 0.76). CONCLUSIONS: Pain relief correlated with improvements in physical function, stiffness, and global rating of disease in patients with hand OA, irrespective of treatment. This suggests that pain or anticipation of pain inhibits physical function and influences patient perception of disease severity in hand OA. These results also suggest that any intervention to relieve the pain of hand OA may improve function and patient perception of disease severity, despite the absence of a disease-modifying mechanism of action. TRIAL REGISTRATION: Clinicaltrials.gov NCT00171652, NCT00171665.

Oxymorphone extended release for the treatment of chronic low back pain: a retrospective pooled analysis of enriched-enrollment clinical trial data stratified according to age, sex, and prior opioid use.

OBJECTIVE: This study assessed the potential effects of age, sex, and prior opioid use on the response to oxymorphone extended release (ER) in patients with moderate to severe chronic low back pain. METHODS: Combined data from 2 placebo-controlled clinical trials with an enriched-enrollment, randomized-withdrawal design were analyzed. In patients aged > or =18 years with chronic low back pain, the dose of oxymorphone ER was titrated to a stable, tolerable, effective dose. Patients who completed titration were randomly assigned to a 12-week double-blind study period with oxymorphone ER or placebo. Oxymorphone immediate release 5 mg was permitted q4-6h, as needed for rescue medication or withdrawal symptoms, for 4 days after randomization and restricted to 10 mg/d thereafter. Pain intensity (100-mm visual analog scale [VAS]; 0 = no pain to 100 = worst pain imaginable) and time to study discontinuation due to lack of efficacy were compared with stratification by age (<65 vs > or =65 years), sex, and prior opioid use. Adverse events were categorized by severity and relation to study medication. RESULTS: Of 575 patients, 348 completed titration and 347 entered the double-blind study phase. There were no significant between-group differences in demographic variables, except that the mean age in the oxymorphone ER group was significantly higher (P = 0.04), and the proportion of men was significantly lower (P = 0.01). There was no significant age difference between the oxymorphone ER and placebo groups stratified by age (<65 vs > or =65 years). Fewer patients aged > or =65 years versus <65 years completed titration (45.0% [36/80] vs 63.0% [312/495]; P = 0.002). The least-squares mean (SEM) differences in VAS pain scores between the oxymorphone ER (n = 174) and placebo (n = 169) groups were significant at each postbaseline assessment (P < 0.001) and at study completion (12.3 [2.8] mm; P < 0.001) and was not significantly affected by age, sex, or prior opioid use. Age and sex had no significant influence on adverse events or discontinuations due to lack of efficacy. More discontinuations due to lack of efficacy occurred among patients in the placebo group (hazard ratio, 5.01; P < 0.001) and among opioid-experienced patients. The latter effect was limited to opioid-experienced patients who received placebo. The rates of discontinuation due to lack of efficacy were similar between oxymorphone ER-treated opioid-naive and opioid-experienced patients (11.4% vs 11.6%). The proportion of patients who experienced opioid-related adverse events was significantly greater in the oxymorphone ER group compared with the placebo group (25.7% vs 16.3%; P = 0.03). The most frequent treatment-emergent adverse events in the oxymorphone ER group were nausea (8.0%), constipation (6.3%), vomiting (4.6%), and diarrhea (4.0%); in the placebo group were nausea (5.8%), diarrhea (4.7%), and increased sweating (2.3%). CONCLUSION: In the enriched population of patients who successfully titrated to oxymorphone ER, oxymorphone ER was effective and generally well tolerated, independent of patients' age, sex, or previous opioid use.