Long-term treatment of rheumatoid arthritis comparing nabumetone with aspirin

This report summarizes the results of a 17-investigator multicenter six-month randomized double-blind parallel group study. The safety and efficacy of nabumetone 1,000 mg taken at bedtime was compared with that of aspirin 900 mg four times daily in the treatment of adult patients with active class II or III classical or definite rheumatoid arthritis. Two hundred sixty-four patients were entered into the study. Two hundred fifty-seven (126 nabumetone and 131 aspirin) patients were evaluable for safety. Two hundred thirty-four (113 nabumetone and 121 aspirin) patients were evaluable for efficacy. There was significant improvement in each of six clinical measurements of efficacy in both treatment groups and little difference between groups. The somewhat greater improvement in articular index and duration of morning stiffness in the nabumetone-treated group did not reach statistical significance. There was an equal percentage of patient withdrawal for lack of efficacy in each group. Overall, the rate of patient withdrawal due to adverse experiences was greater (p = 0.01) for aspirin-treated patients. These experiences were usually dispepsia, abdominal pain, and tinnitus. It was concluded that nabumetone was an effective anti-inflammatory drug in the treatment of rheumatoid arthritis with less toxicity than aspirin.

Results of a six-month study comparing the safety and efficacy of nabumetone and aspirin in the treatment of osteoarthritis

The safety and efficacy of nabumetone (1,000 mg at bedtime) were compared with those of aspirin (900 mg four times daily) in the treatment of osteoarthritis in adult patients in a private practice setting as part of a six-month, double-blind, controlled, randomized, parallel group study. At screening, baseline, and Days 7, 14, 28, 56, 112, and 168, efficacy was evaluated according to independent assessments by the patients and the physician of overall osteoarthritic activity and pain and by the physician's assessment with respect to a defined activity. Of the 40 patients enrolled, 37 were evaluable for efficacy (19 in the nabumetone group and 18 in the aspirin group). Demographic parameters and diagnostic criteria for osteoarthritis were comparable between the groups, although there was a preponderance of women in the nabumetone group. Significant improvement from baseline in all five efficacy parameters was observed in both groups. Safety was evaluated for all 20 enrolled patients in each group. The percentage of aspirin-treated patients who withdrew from the study due to adverse experiences was greater (60 percent versus 20 percent), as was the number with at least one treatment-related adverse experience (19, or 95 percent, versus 11, or 55 percent). Treatment-related adverse experiences described as moderate or severe were reported by 70 percent of the aspirin-treated patients and by 35 percent of the nabumetone-treated patients. In this study, nabumetone 1,000 mg at bedtime had an acceptable safety profile and was as effective as aspirin 900 mg four times daily in the treatment of osteoarthritis.

Endoscopy-controlled study of the safety of nabumetone compared with naproxen in arthritis therapy

Nonsteroidal anti-inflammatory drug (NSAID) gastropathy is now a commonly recognized and reported complication of such arthritis therapy. Significant gastric lesions develop in up to 40 percent of arthritic patients treated with long-term anti-inflammatory doses of NSAIDs, 20 percent of which represents actual ulcer crater disease. This 12-week endoscopy-controlled, double-blind study was constructed to evaluate the safety and efficacy of nabumetone 1,000 mg at bedtime compared with naproxen 250 mg twice daily. A total of 37 patients completed the study, including 29 patients with a diagnosis of osteoarthritis and eight with a diagnosis of rheumatoid arthritis. By posttreatment endoscopy, nabumetone was significantly less toxic to the gastrointestinal tract than was naproxen. The nabumetone-treated group also showed greater improvement in all efficacy variables, with significant improvement noted in three of these five variables in both rheumatoid and osteoarthritic patients.

Nabumetone in the treatment of active adult rheumatoid arthritis

One hundred patients were entered in a six-month, double-blind comparison of 1,000 mg nabumetone once daily and 250 mg naproxen twice daily. Forty-two patients in each arm of the study were evaluable for efficacy; all were evaluable for safety. There was a low incidence of adverse experiences during this study, with no patients withdrawing from the study because of side effects from either drug. Efficacy was equal, with both compounds sharing the same degree and rate of improvement. All of the patients completing the double-blind phase were then switched to open-label treatment with nabumetone. The dosage of nabumetone was gradually increased. At the end of one year, 84 patients remained in the study (52 taking 1,000 mg per day, 23 taking 1,500 mg, and nine taking 2,000 mg). This gradual increase has continued, and, at this time, 61 patients remain in the study (seven taking 1,000 mg per day, 24 taking 1,500 mg, and 30 taking 2,000 mg). There have been very few side effects. From this study, it can be concluded that nabumetone is at least as effective as naproxen and, even at higher doses, had an acceptable safety profile for extended use in patients with rheumatoid arthritis.

Nabumetone versus naproxen in the treatment of osteoarthritis. A six-month trial

The efficacy and safety of nabumetone (1,000 mg at bedtime) and naproxen (250 mg twice daily) were compared in a six-month, randomized, double-blind study of patients with osteoarthritis. Forty patients were entered in the study and completed a washout phase, and 37 were evaluable for efficacy. Of these, 18 patients received nabumetone and 19 received naproxen. Both treatment groups had significant improvement from baseline in all of the efficacy variables measured. All 40 patients were evaluated for safety. Fifty percent of the patients treated with nabumetone and 65 percent of the patients treated with naproxen had at least one drug-related or unknown-related adverse experience. Fifteen percent of patients in both groups had treatment-related adverse experiences that were moderate or severe. There were no statistically significant differences in the two treatment groups with regard to efficacy or adverse experiences.

Review of the experience with nabumetone in clinical trials outside of the United States

Nabumetone, a new nonsteroidal anti-inflammatory agent, has undergone extensive clinical evaluation in a number of countries. There have been over 4,000 patients treated, including nearly 1,000 elderly patients and over 1,100 patients who have received nabumetone for more than one year. A total of 2,400 of these patients with a variety of rheumatic disorders have been investigated in studies outside of the United States. Studies in rheumatoid arthritis and osteoarthritis have demonstrated that nabumetone is effective in the treatment of these conditions and that this effectiveness is maintained in many patients in the long term. Nabumetone appears to be well tolerated and there is no evidence from patients receiving treatment for 12 months or more of any clinically significant adverse effects on hematologic or biochemical parameters. Thus, these studies support the use of nabumetone in the treatment of rheumatoid arthritis and osteoarthritis.

Evaluation of nabumetone in the treatment of active adult rheumatoid arthritis

The safety and efficacy of nabumetone and placebo were compared in a three-week, multicenter, double-blind, randomized, parallel evaluation involving patients with class II or III definite or classical rheumatoid arthritis. No patient received concomitant treatment with other nonsteroidal anti-inflammatory agents; however, disease-modifying agents (gold, steroids) were permitted. Of the 139 patients who entered the double-blind phase of the study, all were evaluable for safety, and 113 were evaluable for efficacy. Sixty-one patients received 1,000 mg of nabumetone per day at bedtime, and 50 were given placebo tablets; patients in both groups were permitted up to 3,250 mg of acetaminophen per day as needed for pain. After three weeks, nabumetone-treated patients exhibited a greater degree of improvement from baseline than did the placebo-treated patients, and the degree of improvement was statistically significant for four of seven variables.

Single-blind comparative study of nabumetone (Relafen) versus naproxen in the treatment of rheumatoid arthritis

Forty-seven patients with active rheumatoid arthritis were entered into a single-blind study to compare the safety and efficacy of nabumetone with naproxen. Patients were randomly assigned to receive a daily dose of 2 g of nabumetone or 1 g of naproxen after a placebo-washout period of at least three days. In addition to the usual clinical and laboratory measurements of disease activity, thermographic assessment was carried out at each visit and the heat distribution index was calculated. In addition, the safety and tolerance were assessed. Patients had improvement in severity of pain, severity and duration of morning stiffness, and articular index, and there was no statistical difference between the two treatment groups. By the end of six months, 13 patients had withdrawn from treatment; five patients in the naproxen treatment group and five in the nabumetone group were withdrawn from the study due to lack of efficacy. In no patient from the nabumetone group did an adverse reaction develop. In one patient in the naproxen group, a severe decrease in white blood cell count developed, and a skin rash and swollen gums developed in another patient. We conclude that nabumetone is well tolerated and of equal efficacy to naproxen in the treatment of active rheumatoid arthritis.

Safety evaluation of nabumetone in United States clinical trials

A total of 1,924 persons (rheumatoid arthritis, 835; osteoarthritis, 1,073; volunteers, 16) received nabumetone in United States clinical trials. Nine hundred eighty-eight patients have received nabumetone treatment for periods of more than one year, and 375 patients have received treatment for longer than two years. Four hundred eighty patients over 65 years of age have received treatment with nabumetone, and 224 of these elderly patients have received treatment for periods of more than one year. The nabumetone dose most commonly used in all double-blind trials was 1,000 mg at night. In long-term, open-label studies, which were usually extensions of the double-blind trials, patients could increase the dose to 2,000 mg per day. Nine hundred nineteen patients received doses of more than 1,000 mg per day. Adverse experience information was collected at each visit, including information for some patients receiving treatment for more than three years. Laboratory data were collected periodically throughout the trials, and the data were assessed for trends over time. The adverse experience pattern observed for nabumetone is similar to that described for clinical trial data for other nonsteroidal anti-inflammatory drugs. However, it is noteworthy that the pattern observed for nabumetone is from clinical trials with approximately 1,000 patients receiving treatment for periods of one year or more. This long-term patient exposure in clinical trials far exceeds long-term clinical trial data for other agents. The types and frequencies of adverse experiences reported by persons treated with nabumetone are relatively constant over the long time period covered by these trials. Also, the adverse experience patterns remained generally constant over time for various populations: all patients, patients 65 or older, female patients, male patients, and patients who received an increased dose of nabumetone. Although some statistically significant trends were detected for some laboratory parameters, there was little indication of significant clinical patterns. Although there were patients with individually important laboratory values, nabumetone was not associated with clinically important adverse laboratory patterns. Overall, the adverse experience data and laboratory data indicate that nabumetone is safe for the treatment of adult patients with rheumatoid arthritis or osteoarthritis.

Endoscopic studies of nabumetone in patients with rheumatoid arthritis. A comparative endoscopic and histologic evaluation

Gastric tolerance to 1 g of nabumetone administered in a single nightly dose was assessed in two trials in patients with rheumatoid arthritis. Gastroscopy and histology of mucosal biopsy specimens were performed before and after the end of treatment in both trials. Trial 1 was an open study that compared the effects of 1 g of nabumetone at night with those of naproxen (dose, 500 mg twice daily) and indomethacin (dose, 50 mg three times daily) in 41 hospitalized patients. After three weeks of treatment, nabumetone was significantly better tolerated than naproxen or indomethacin. Trial 2 was a randomized trial with 24 patients per group that compared 1 g of nabumetone given at night with 250 mg of naproxen given in the morning and 500 mg given at night for a period of three months. This single-blind study revealed that the number of patients with microscopic or macroscopic mucosal lesions was significantly smaller following intake of nabumetone. Concerning efficacy, as judged clinically by a rheumatologist, treatment with nabumetone was superior as well.

Nabumetone: a single-center three-week comparison with placebo in the treatment of rheumatoid arthritis

Forty-six patients with definite or classical rheumatoid arthritis were entered into a three-week, double-blind, randomized, parallel study of nabumetone, 1,000 mg at bedtime, compared with placebo. Fifteen nabumetone-treated and 12 placebo-treated patients were evaluated for efficacy variables including physician's opinion of rheumatoid arthritis activity, patient's opinion of rheumatoid arthritis activity, articular index, morning stiffness, 50-foot walking time, grip strength, and acetaminophen consumption. Between-group analysis of improvement over baseline was significantly (p less than 0.05) greater for nabumetone-treated patients for six of the seven variables. Nabumetone was significantly favored over placebo in three global evaluations and significantly more placebo-treated (75 percent) than nabumetone-treated (20 percent) patients withdrew from the study due to an unsatisfactory therapeutic response. Of the 38 patients receiving the study medication, 22 percent of nabumetone-treated and 5 percent of placebo-treated patients reported adverse experiences either related to treatment or for which the relationship to treatment was unknown. No patients were withdrawn from the study as a result of these experiences and no long-term sequelae or clinically significant laboratory abnormalities were reported.

Comparison of the safety and efficacy of nabumetone and aspirin in the treatment of osteoarthritis in adults

A six-month, multicenter, double-blind study compared the efficacy and safety of two therapeutic regimens in 332 patients with osteoarthritis. The patients received either 1,000 mg of nabumetone as a single bedtime dose or 900 mg of aspirin in four divided doses. At the end of the study, patients in both treatment groups showed significant improvement from baseline for all five parameters; no statistically or clinically significant differences were observed between the groups. The safety data did reveal clinically and statistically significant differences between the groups. Aspirin-treated patients experienced a greater frequency of withdrawal from the study because of adverse experiences (34 percent versus 13 percent), a greater incidence of having at least one treatment-related adverse experience (73 percent versus 52 percent), a greater percentage of patients with at least one moderate or severe treatment-related adverse experience (47 percent versus 22 percent), and a greater percentage of patients with treatment-related adverse experiences affecting the gastrointestinal system (43 percent versus 32 percent) or the inner ear (32 percent versus 10 percent). The results of this study demonstrated that nabumetone, 1,000 mg at bedtime, is as efficacious as aspirin, 900 mg four times daily, produces fewer adverse effects, and is indicated in the treatment of osteoarthritis.

Preclinical overview of nabumetone. Pharmacology, bioavailability, metabolism, and toxicology

Nabumetone is a novel nonacidic nonsteroidal anti-inflammatory drug (NSAID) developed by Beecham Pharmaceuticals. After absorption, nabumetone undergoes extensive metabolism, the main circulating material being 6-methoxy-2-naphthylacetic acid, (BRL 10720). This, unlike nabumetone, is a potent inhibitor of prostaglandin synthesis and is considered to be the active anti-inflammatory metabolite. Nabumetone is active in all standard laboratory models of inflammation and has a greater ratio of active to gastric irritant doses (therapeutic ratio) in the rat than any other NSAID tested. The lack of effect on the gastric mucosa in all species has been a notable feature of the toxicology studies. In humans, relative bioavailability is similar after administration of different dose levels, the mean terminal plasma half-life of BRL 10720 being about 24 hours, allowing for once-daily dosing. The half-life of BRL 10720 does not change on repeated dosing, and no unexpected or irreversible accumulation occurs in elderly patients.

Nabumetone in the treatment of skin and soft tissue injury

Nabumetone, a new nonsteroidal anti-inflammatory agent, has been evaluated for the treatment of skin and soft tissue injury, including sports injury, in clinical trials involving nearly 1,000 patients. Its efficacy, safety, and tolerance in these patients is reviewed. The efficacy of nabumetone in the treatment of soft tissue injury has been demonstrated to be similar to that of soluble aspirin, ibuprofen, and naproxen. It was not possible in these studies to demonstrate a definite advantage over placebo, and the reasons for this are discussed along with some suggestions for future studies. There were no serious adverse experiences reported, and nabumetone was well tolerated and compared favorably with the other agents used, including placebo. It caused significantly fewer gastrointestinal side effects than soluble aspirin. Nabumetone is an appropriate choice of nonsteroidal anti-inflammatory drug for the treatment of sports injury.

Nabumetone therapy of osteoarthritis. A six-week, placebo-controlled study

Following a washout period, one hundred six patients with osteoarthritis were randomly assigned single daily doses of either 1,000 mg of nabumetone or placebo given at bedtime as part of a six-week, controlled, double-blind study. Forty-seven patients received nabumetone, whereas 48 patients were given placebo. Treatment groups were comparable for demographic characteristics, baseline efficacy assessments, and diagnostic criteria for osteoarthritis. Nabumetone-treated patients had absolute improvement, as well as relative improvement in comparison with placebo, both clinically and statistically. There were no clinical or statistical differences in safety variables between the two groups. When given once daily at bedtime, nabumetone was effective and had a good safety profile in patients with osteoarthritis.

Six-month multi-center study comparing nabumetone with naproxen in the treatment of osteoarthritis

This six-month, double-blind, controlled, randomized, parallel study at 13 medical centers compared the safety and efficacy of nabumetone (1,000 mg taken at bedtime) with that of naproxen (250 mg twice daily) in the treatment of osteoarthritis in symptomatic adult outpatients. Five efficacy parameters were measured: patients' assessment of overall osteoarthritis activity and pain, physicians' assessment of overall osteoarthritis activity and pain, and physicians' assessment of pain with respect to a declined activity. All 489 patients who took medication were included in the evaluation of safety, and 455 patients (227 in the nabumetone group and 228 in the naproxen group) were evaluated for efficacy. Significant improvement in all five efficacy parameters occurred in both groups. No significant differences were found between the two groups at the end of the study in any of the five efficacy parameters. Twenty-three percent of nabumetone and 17 percent of naproxen patients withdrew from the study for lack of efficacy. At least one possible or probable treatment-related adverse experience was reported for 45 percent of nabumetone-treated patients and 42 percent of those given naproxen, and in 19 percent of the nabumetone-treated and 18 percent of the naproxen-treated patients these experiences were moderate or severe. However, only 7 percent of patients in each group withdrew from the study due to adverse experiences. Nabumetone and naproxen have comparable safety and efficacy, suggesting that a single, nighttime dose of nabumetone is a convenient, effective, and safe treatment for osteoarthritis.

Exposure concentration versus environmental concentration: a field survey in organic solvent workplaces

The relationship was investigated between the environmental concentrations in workplaces and the concentrations in the breath zones of the workers therein. The former was measured in 47 organic solvent workplaces of various types taking both the grid-sampling strategy (Measurement A) and a spot-air sampling to detect possible maximum exposure (Measurement B), while the latter was determined by the application of personal samplers to 328 workers. Although a low yet significant correlation was observed between the results of Measurement A (i.e., the combination of the geometric mean and the geometric standard deviation of the environmental concentration) and the exposure concentration, excess exposure (i.e., over occupational exposure limit exposure) would occur in some workplaces when the occupational exposure limit itself be used as the limit value for the setting of criterion for environmental concentration. The analyses of the experiences suggest no excess exposure would be expected if half the occupational exposure limit be employed as the limit value.

Long-term mortality study of oil refinery workers. IV. Exposure to the lubricating-dewaxing process

A retrospective cohort mortality study of 1,008 male oil refinery workers who ever worked on the lubricating-dewaxing process of the lube oil department and who have been followed for a period of 43 years is presented. These workers were exposed to a number of solvents, primarily methyl ethyl ketone [(MEK) CAS: 78-93-3] and toluene (CAS: 108-88-3), but at levels far below the current Occupational Safety and Health Administration's standard. The standardized mortality ratio (SMR) for all causes (0.70) and the SMR for cancer (0.86) are much lower than unity when they are compared to the mortality experience of the U.S. population. Also observed in this study were 8 prostate cancer deaths (4.4 expected) with an SMR of 1.82, which was not statistically significant (P = .16). Seven of these 8 prostate cancer deaths occurred among nonwhite males, who showed an SMR of 2.47 (P = 0.53). However, only 1 prostate cancer death was seen among workers specifically assigned to the MEK units. The remaining deaths occurred among maintenance workers who had lube oil department-wide assignments. This cancer risk increased with increasing duration of employment in the lube oil department. A latency of 20 years or more was also observed for these prostate cancer deaths. In this study the processing of lubricating oils was found to be at least as important as the MEK solvents, and department-wide maintenance workers were as much at risk as the MEK unit workers. In view of this finding and findings obtained by others, it seems prudent to continue to study lubricating-dewaxing process workers, including the medical monitoring of all such workers for prostate cancer.

Cases from the Aerospace Medicine Residents' Teaching File

"From the aerospace medicine residents' teaching file: toxic peripheral neuropathy, sacroiliitis, and mitral valve prolapse." The clinical presentation, evaluation and diagnosis of an aviator exposed to N-Hexane and Butanone are discussed. The aeromedical disposition of this patient, who also had mitral valve prolapse and subclinical sacroiliitis, is also presented.

Nabumetone: a double-blind study in osteoarthrosis

A double-blind, placebo-controlled, crossover trial was carried out to assess the efficacy and tolerance of nabumetone in patients with osteoarthrosis of the hip or knee. Patients were allocated at random to receive either 1 g nabumetone twice daily or matching placebo for 2 weeks and then crossed over to the alternative treatment for a further 2 weeks. Clinical assessments of pain and function were made before and at the end of each treatment period. Seventeen of 18 patients completed the trial and the results showed that most clinical parameters assessed were improved during active treatment, with significantly more patients preferring nabumetone (p less than 0.001) to placebo. Only 1 patient reported what was considered to be a drug-related adverse event (irritation of the scalp) during nabumetone treatment.

Nabumetone, a new non-steroidal anti-inflammatory drug: a comparison with naproxen

Nabumetone, 500 mg two nocte, was compared with naproxen, 250 mg two nocte and one mane, in the management of 24 patients with rheumatoid arthritis attending an outpatients clinic. Both drugs were generally well tolerated and were of comparable efficacy in the dose employed. Similar numbers incurred side effects while taking either drug, but severe side effects, requiring withdrawal from the trial in two cases, were restricted to those patients taking naproxen. As patients known to be intolerant to naproxen were excluded from the trial, the results could have been expected to favour naproxen in this respect. Nabumetone may have a useful role in the management of patients with poor tolerance of other anti-inflammatory drugs.