Samarium-153-EDTMP in the treatment of refractory rheumatoid arthritis.

We examined the preliminary safety and efficacy of intravenous samarium-153-EDTMP (Sm-153) in the treatment of refractory rheumatoid arthritis (RA). In an open-label sequential group comparison of 0.5, 1.0, and 2.0 mCi/kg, Sm-153 was administered as a single intravenous infusion to 24 patients with refractory disease. Across treatment doses, the frequency of American College of Rheumatology (ACR) 20% responses was 25%, 29%, 25%, and 33% at 2, 4, 8, and 12 weeks, respectively. Expected significant declines in absolute neutrophil count, hemoglobin, and platelet counts were observed with nadirs seen between 2-4 weeks. Sm-153, at doses of 0.5 and 1.0 mCi/kg, is well tolerated but minimally effective in the treatment of refractory RA as measured using ACR response criteria.

Rheumatoid arthritis lung disease. Determinants of radiographic and physiologic abnormalities.

OBJECTIVE: To determine the prevalence and important clinical predictors of radiographic and physiologic abnormalities indicative of rheumatoid arthritis interstitial lung disease (RA-ILD). METHODS: An unselected cohort of patients with a confirmed diagnosis of RA and known lung disease were identified (n = 336) and evaluated for RA disease activity and severity. Outcomes included abnormalities determined by the pulmonary function tests of forced vital capacity (FVC) and diffusion capacity for carbon monoxide (DLco), and/or chest radiographic findings of interstitial infiltrates. We used multivariable statistical modeling to determine the independent significance of cigarette smoking and other RA-specific factors on the pulmonary abnormalities of interest. RESULTS: At least 1 of the 3 abnormal findings was identified by pulmonary tests in 32.4% of all patients. These abnormal findings included an FVC < 80% of predicted in 42 patients, a DLco < 80% of predicted in 64 patients, and evidence of radiographic interstitial infiltrates in 40 patients. After statistical adjustment for confounding factors, pack-years of cigarette smoking remained a significant predictor of low DLco (beta = -0.07, 95% confidence interval [95% CI] -0.09, -0.04), low FVC (beta = -0.003, 95% CI -0.006, -0.0004), and interstitial abnormalities on chest radiograph (odds ratio for > or = 25 pack-years = 3.76, 95% CI 1.59, 8.88). The Health Assessment Questionnaire (HAQ) Disability Index (DI) was also an important risk factor for the decline in both the DLco (beta = -1.15, 95% CI -2.00, -0.30) and FVC (beta = -0.23, 95% CI -0.32, -0.13). CONCLUSION: Although RA disease activity/severity (particularly as defined by the HAQ DI) was important, smoking was the most consistent independent predictor of radiographic and physiologic abnormalities suggestive of ILD in RA.

Low-dose methotrexate may cause air trapping in patients with rheumatoid arthritis.

Both rheumatoid arthritis (RA) and methotrexate (MTX) are reported to be associated with the development of pulmonary disease. To determine whether MTX enhanced the risk of developing abnormalities in pulmonary function in patients with RA, we prospectively studied 31 subjects (12 male, 19 female) with the diagnosis of classic RA for an average period of 4.4 yr (range, 1 to 5 yr). Each subject was placed on low-dose weekly MTX (mean 17 mg, range 2.5 to 40) for control of RA symptoms. Other medications included non-steroidal anti-inflammatory agents and prednisone if required for control of arthritis symptoms. No other immunosuppressive therapy was used. Each subject was evaluated by pulmonary function tests (PFT) and chest X-ray initially, and at 1, 2, 3.5, and 5 yr. Chest X-rays obtained initially and at the end of the study period were found to be normal. The percent predicted values for initial PFTs in the study group were within the normal range. From the beginning to the end of the observation period, the following mean changes in lung function were observed: 1.9% increase in TLC, 5.1% increase in residual volume (RV), 1.8% increase in FVC, 0.71% decrease in FEV1, 14.7% improvement in alveolar-arterial oxygen (A-aO2) difference, and a 12.7% increase in single-breath diffusing capacity (DLCO). To determine whether MTX (average dose, weekly dose, or cumulative dose) was significantly related to changes in pulmonary function, we used multivariate techniques to control for the initial measure of lung function while assessing the relationship between MTX and the subsequent measures of lung function.(ABSTRACT TRUNCATED AT 250 WORDS)

Low dose long-term corticosteroid therapy in rheumatoid arthritis: an analysis of serious adverse events.

PURPOSE: The purpose of this study was to better define the toxicity of low dose (less than or equal to 15 mg/d prednisone or equivalent) long-term (greater than 1 year) corticosteroids in the treatment of rheumatoid arthritis (RA). PATIENTS AND METHODS: We examined an historical cohort of 112 RA patients on low dose (6.1 +/- 3.1 mg/d, mean +/- SD) long-term (6.2 +/- 4.6 years) prednisone (CS) and compared them to 112 matched RA patients not using prednisone (CO). CS were matched one-to-one with CO for sex (75% women), age (+/- 5 yrs), race (98% white), and duration of disease (+/- 5 yrs). Subjects were determined by review of unselected medical records from three distinct rheumatology practice settings. For CS, charts were abstracted from the date of prednisone start for predefined adverse events (AEs). RESULTS: Ninety-two (92) AEs were noted in CS versus 31 in CO and included: fracture (CS:21 versus CO:8), serious infections (CS:14 versus CO:4), gastrointestinal (GI) bleed or ulcer (CS:11 versus CO:4), and cataracts (CS:17 versus CO:5). At time of first AE, CS prednisone average dose was 7.0 +/- 2.6 mg with a duration of 4.9 +/- 3.9 years. Stepwise multiple logistic regression analysis was used to create a model which included all clinically relevant variables and all parameters significantly different at the cohort inception. Prednisone average dose of greater than 10 to less than or equal to 15 mg/d correlated most strongly with the development of an AE (Odds Ratio (OR) = 32.3, 95% Confidence Interval (CI) 4.6, 220). Average prednisone 5 to 10 mg (OR = 4.5, 95% CI 2.1, 9.6), RA nodules (OR = 3.9, 95% CI 1.9, 8.0), and bony erosions (OR = 2.4, 95% CI 1.2, 4.7) also entered the final model. Kaplan Meier survival curves for the development of the first AE showed a dose-response relationship between prednisone and AE occurrence, independent of rheumatoid nodules. Subset analyses utilized a nested case control design for the development of three serious AEs: fractures, serious infections, and GI events. These analyses revealed possible relationships between prednisone use and the development of each specific AE (prednisone use OR: fracture 3.9, 95% CI 0.8, 18.1; infection 8.0, 95% CI 1.0, 64.0; and GI event 3.3, 95% CI 0.9, 12.1). CONCLUSIONS: Although disease severity is an important confounding factor, low dose long-term prednisone use equal to or greater than 5 mg/d is correlated with the development of specific adverse events in a dose-dependent fashion.

Aspirin is not associated with more toxicity than other nonsteroidal antiinflammatory drugs in patients with rheumatoid arthritis treated with methotrexate.

OBJECTIVE: To compare the clinical and laboratory toxicities of aspirin vs nonsteroidal antiinflammatory drugs (NSAID) in combination with low dose methotrexate (MTX). METHODS: We retrospectively examined 34 patients with rheumatoid arthritis (RA) who completed 12 months of a prospective MTX trial. Analysis included descriptive and logistic regression. RESULTS: Twelve patients took an average of 4.5 g aspirin daily; 22 patients took other NSAID at stable doses. Limiting toxicity was not different between aspirin and NSAID treatment groups, respectively, for stomatitis (33 vs 27%), gastrointestinal symptoms (25 vs 18%), hepatic (25 vs 27%), or other toxicity. However, using logistic regression procedures, weight adjusted weekly MTX dose and prednisone dose correlated with toxicity. CONCLUSION: While toxicity is common when aspirin or NSAID are used with MTX to treat RA, there is no clinical difference between aspirin and NSAID with respect to that toxicity during 12 months of therapy.

Adverse experience with methotrexate during 176 weeks of a longterm prospective trial in patients with rheumatoid arthritis.

Adverse experience occurred with a high frequency in a longterm (greater than 3 years), prospective, double blind, followed by an open trial of methotrexate (MTX) therapy in 45 patients with rheumatoid arthritis (RA). Adverse experiences occurred in 96% of patients, and the discontinuation rate was 44% over 176 weeks. No hepatic or pulmonary fibrosis occurred. Unusual toxicities included weight loss (2 patients), systemic fungal infections (2 patients), and transient noncirrhotic ascites (1 patient). Baseline white blood cell counts and creatinine may help predict adverse experiences. The full dose-toxicity spectrum of MTX RA is not yet fully defined.

Effect of aspirin and sulindac on methotrexate clearance.

The pharmacokinetics of low dose methotrexate (MTX) were evaluated in 12 rheumatoid arthritis patients in the presence and absence of steady-state levels of salicylic acid (ASA) and sulindac (SU). Using a Latin square design, patients were given MTX plus ASA (mean 3.4 g/day), MTX plus SU (mean 400 mg/day), or MTX alone. On a background of at least one year of regular MTX therapy, patients received 10 mg/m2 MTX iv (mean 17.8 mg) given after at least 2 weeks of treatment with each of the above regimens. Plasma concentrations of MTX and 7-hydroxymethotrexate (7-OH-MTX) were measured using HPLC. No differences in MTX clearance (Cl) were found comparing MTX alone, MTX + ASA, and MTX + SU. However, if one particular subject that had a very low clearance when receiving MTX alone was excluded, there was a statistically significant decrease in MTX clearance when either ASA or SUL were present. It is also noteworthy that ASA significantly increased the exposure of the subject to 7-OH-MTX and, to a lesser extent, so did sulindac. Since 7-OH-MTX has been shown to be an active metabolite when given for cytotoxic effects at higher doses and because it has been show to be nephrotoxic at doses a thousand-fold greater than used in rheumatoid arthritis, nonsteroidal anti-inflammatory drugs should be used cautiously with MTX until further large scale safety studies are conducted. The data indicate that if a clinically significant interaction were to occur, ASA is more likely than SU to interact with MTX.

Biliary elimination of low-dose methotrexate in humans.

We studied the pharmacokinetics of methotrexate (MTX) in a 64-year-old man with rheumatoid arthritis. After 6 months of treatment, acute clinical complications arose, requiring emergency laparotomy and cholecystotomy. A biliary tube was inserted, and this allowed for direct analysis of the bile. The pharmacokinetics of 2 separate doses of MTX (orally and intravenously) were assessed (dosage 10 mg/m2). No substantive differences in the pharmacokinetics were found between pre- and post-cholecystotomy MTX treatment, including clearance rates, volumes of distribution, and terminal half-lives. The results, however, demonstrated a change in the bioavailability of the drug (decreasing from 84.7% to 38.9%). Based on extrapolations of the data, with assumed rates of bile flow, the findings also suggest that there is substantial biliary elimination of MTX (8.7-26.0%) and its principal 7-hydroxy metabolite (1.5-4.6%).

Increasing methotrexate effect with increasing dose in the treatment of resistant rheumatoid arthritis.

Forty-six patients with recalcitrant rheumatoid arthritis entered a trial encompassing a 2-week inpatient period plus a 16-week, randomized double blind, parallel study comparing placebo, 5 mg/m2 and 10 mg/m2 oral weekly methotrexate (MTX). An additional 6 patients, given 20 mg/m2 MTX, contributed to the toxicity, but not the efficacy analysis. All patients had "failed" either gold or D-penicillamine. A linear dose response relationship (placebo vs 5 mg/m2 vs 10 mg/m2) was found for 5 of 11 outcome variables: patient pain and patient global scale, physician global scale, joint tenderness count and activity of daily living scale (p less than 0.05 for each). Gastrointestinal toxicity (p = 0.002), dyspepsia (p less than 0.03) and stomatitis (p less than 0.09) occurred more commonly with MTX, and a general trend, although not significant, was found toward a dose toxicity relationship.

Pharmacokinetics of low-dose methotrexate in rheumatoid arthritis patients.

The pharmacokinetics and bioavailability of low-dose methotrexate (MTX) (10 mg/m2) were evaluated in 41 subjects who had definite or classical rheumatoid arthritis as defined by the American Rheumatism Association criteria. Subjects received 10 mg/m2 (to the nearest 2.5 mg) of MTX in a single oral dose and a single intravenous (iv) dose one week apart. Serum concentrations for this low-dose regimen were monitored using a radiochemical ligand binding assay. The results indicate the MTX is cleared from the plasma at a rate of 84.6 mL/min/m2. The terminal half-life was approximately 6 h. The volumes of distribution at steady state and for the central compartment were 22.2 and 13.5 L/m2, respectively. The mean residence time in the body, in the systemic circulation, and in the periphery were estimated to be 4.7, 3.0, and 1.7 h, respectively, with a peripheral single-pass mean transit time of 6.0 h and an intrinsic mean residence time in the periphery of 7.9 h. The mean absorption time was 1.2 h and the oral bioavailability was 0.70. The ratio of synovial fluid concentration to serum concentration 4 and 24 h after a dose was found to be approximately 1.0, indicating that at least within that time range serum and synovial fluid concentrations are approximately equal. Because of conflicting results and insufficient data from previous high-dose pharmacokinetic studies, it is difficult to say whether or not low-dose MTX pharmacokinetics differs from those of high-dose MTX.