Amphotericin B methyl ester hydrochloride and amphotericin B: comparative acute toxicity.

In single-dose parenteral studies with mice and dogs, the methyl ester hydrochloride of amphotericin B proved to be significantly less toxic than the parent compound, especially to the kidney.

Carcinogenicity of the antischistosomal nitrofuran trans-5-amino-3-[2-(5-nitro-2-furyl)vinyl]-1,2,4-oxadiazole.

The antischistosomal and antitrypanosomal drug trans-5-amino-3-[2-(5-nitro-2-furyl)vinyl]-1,2,4-oxadiazole [(SQ18506) CAS: 28754-68-9; (E)-amino-3-(2-(5-nitro-2-furyl)-vinyl)-1,2,4-oxadiazole] was carcinogenic for both male and female CD-1 mice when it was administered either in the diet or by gastric intubation. Dose-dependent increases in tumors of the forestomach and lymphatic tissues were observed in all groups receiving SQ18506 including mice infected with Schistosoma mansoni. The predominant tumor observed was squamous cell carcinoma of the forestomach. The presence or absence of schistosome infection did not appear to alter the incidence or distribution of tumors at comparable doses of SQ18506. The incidence of bladder tumors was positively correlated with the dose in gastric intubation studies and inversely correlated with the dose in dietary studies. The carcinogen N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (CAS: 24554-26-5) was fed to male and female CD-1 mice in the diet as a positive control. The predominant tumor observed in these groups was transitional cell carcinoma of the bladder. These data indicate that SQ18506 is unsuitable for use in the treatment of parasitic diseases.

Preclinical safety testing of new drugs.

Preclinical safety testing is one important step in the development of new medicines. The requirements of such testing are the subject of government regulations and may vary in details, but not in general principles, in different countries around the world. The approach to preclinical safety testing of new drugs is multidisciplinary and requires the expertise of members from many different fields of science. The procedures described are guidelines rather than fixed protocols; they are subject to modifications according to the specific phamracological nature of the drug to be tested and also to the preference of the individual investigator. Under certain circumstances, special studies are necessary, such as electron microscopy, histochemistry, radioautography, and cytogenetics,--just to name a few. Routine studies for the safety assessment of new drugs include: (1) acute studies, (2) multiple-dose studies including carcinogenicity tests, (3) studies of fertility and general reproductive performance, (4) teratology studies, (5) perinatal and postnatal studies, (6) multiple-generation studies and (7) irritation studies.

Efficacy and safety of a combination therapy of methotrexate, chloroquine and cyclophosphamide in patients with refractory rheumatoid arthritis: results of an observational study with matched-pair analysis.

The efficacy and safety of a combination of methotrexate (MTX), chloroquine (CQ) and cyclophosphamide (CYC) were studied in patients with refractory rheumatoid arthritis. A single-centre, matched-pair observational study with prospectively gathered data was performed. Fifty-six patients who had previously failed with MTX were treated with 15 mg MTX per week, 50 mg CYC three times a week and 250 mg CQ per day (group A). A 50% improvement of the swollen joint count was required to continue therapy. Data were compared with the results of the previous MTX therapy in the same group and with a matched-patient cohort receiving MTX monotherapy for the first time (group B). In group A, the combination therapy resulted in a significant decline of the swollen joint count after 1 year, in contrast to the previous MTX monotherapy in the same group. Complete remission of joint swelling was achieved in 13 patients (23%), compared with 26 patients in group B (47%). The median duration of effective combination treatment in group A was significantly longer than preceding therapies with MTX alone (19 vs 13 months, p<0.05). However, patients in group B could be treated for a median of 57.5 months (p<0.0001 compared with group A). Side-effects were comparable in both groups. The applied DMARD combination is safe and beneficial in a significant proportion of patients if MTX monotherapy is ineffective.

Treatment of refractory rheumatoid arthritis with low-dose cyclophosphamide. Long-term follow-up of 108 patients.

Although cyclophosphamide (CYC) is an effective drug in the treatment of refractory rheumatoid arthritis (RA), the application of this drug in RA has largely been abandoned, due to potentially life-threatening adverse events such as myelosuppression and cancer development. However, the question remains open, whether it is possible to balance the toxicity and the efficacy of CYC with low-dose therapy. 108 patients with refractory RA or with vasculitic organ involvement were treated with 50 mg CYC per day. Joint indices and laboratory parameters were gathered prospectively and the occurrence of serious side effects was monitored over a median of 10 years. The efficacy was surveyed in six months intervals. A 50% improvement of the swollen joint count was required to continue therapy. A long-term follow-up was performed to survey the incidence of malignancies. 85 patients dropped out within the first year. Only four patients were treated for longer than 4 years. In the total cohort, 50 patients were withdrawn due to the lack of efficacy, 34 patients had to discontinue because of adverse events, and 9 patients dropped out for both reasons. Gastrointestinal intolerance was the most frequent adverse event that led to the discontinuation of the drug, followed by myelosuppression. Five patients suffered from 6 malignancies occurring after a median of 4.5 years after cessation of treatment. Treatment of RA patients with 50 mg CYC per day resulted in a more favorable rate of serious adverse events and a markedly lower incidence of tumors compared to the treatment with 75 to 150 mg per day described in the literature. However, the long-term efficacy of this regimen was poor in our cohort.

Long-term application of disease modifying antirheumatic drugs (DMARD). A single-center, observational study of 1681 patients with rheumatoid arthritis (RA).

OBJECTIVE: To study the long-term efficacy and safety of methotrexate (MTX), intramuscular gold, azathioprine (AZA), chloroquine (CQ), sulphasalazine (SASP), and D-penicillamine (DPA) in rheumatoid arthritis (RA) patients. METHODS: Between 1979 and 1994, clinical data were prospectively gathered in a single center. 1681 patients were followed-up for at least 4 years. A 50% reduction of the swollen joint count was required to continue therapy. In addition, a modified Lansbury index, the Keitel function test, and laboratory parameters were determined every six months. Side effects leading to the discontinuation of treatment were recorded as well. RESULTS: After an observation period of more than four years, 39.6% and 28.3% of patients were taking MTX and AZA, respectively; 18.2% were receiving gold, 16.9% remained on DPA. SASP and CQ were still applied in 13.5% and 6.6%. MTX, AZA and SASP had a drop-out rate due to toxicity of 15.9%, 15.3% and 17.7%, whereas 34.8% had to discontinue CQ (gold: 27.4%, DPA: 26.9%). The majority of dropouts occurred within the first year of treatment. Subgroups of seropositive patients and patients with rheumatoid nodules had a poorer treatment efficacy irrespective of the DMARD. CONCLUSION: In the long-term application, MTX was the most efficient compound, followed by AZA, whereas CQ had the poorest drug survival. Our results underline the value of long-term observations under the conditions of clinical practice as a supplement to controlled clinical trials.

Loss of functional capacity caused by a delayed onset of DMARD therapy in rheumatoid arthritis. Long-term follow-up results of the Keitel function test. Brief definite report.

The aim of this analysis was to investigate the impact of the postponement of DMARD therapy on the functional outcome of rheumatoid arthritis after 10 years of disease. 321 individuals with a disease duration of at least ten years were selected out of a cohort of more than 1800 patients. Two groups were analysed separately: patients who started DMARD therapy within the first year of their disease, and patients who received their first DMARD not earlier than five years after the onset of RA. The Keitel functional index was determined in every patient after 10 years of RA. After 10 years of disease, the swollen joint count and the ESR had decreased in both groups to a comparable degree. However, patients with early treatment performed significantly better in the Keitel test compared to the group with delayed therapy. Although patients with seropositive RA or rheumatoid nodules had a worse outcome in general, the benefit of early treatment was also significant in these subgroups.

[Wound infection following surgical intervention for rheumatism and its relationship to preoperative basic therapy]. / Wundinfektionen nach rheumachirurgischen Eingriffen und ihre Beziehungen zur präoperativen Basistherapie.

Theoretically, slow acting antirheumatic drugs are capable of affecting the body's infection resistance. We have therefore analyzed the records of all 558 RA-patients hospitalized and operated on at our department from 1985-1987 with respect to the incidence of post-surgical wound infections and possible links to previous treatment with slow acting antirheumatic drugs. A total of 2456 operations were performed, or 4.4 per patient. Severe complications due to infection occurred in 24 patients (0.98%). The slow acting drugs had no effect on the complications rate.

Detection of insulin-like growth factor I and II in synovial tissue specimens of patients with rheumatoid arthritis and osteoarthritis by in situ hybridization.

OBJECTIVE: To study the expression of insulin-like growth factor I and II (IGF I and II) in synovial tissue specimen of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). METHODS: Synovial tissue sections were examined for the expression of IGF I and II by in situ hybridization using digoxigenin labeled antisense and sense RNA probes. RESULTS: The antisense probe of IGF I reacted with all specimens. IGF II mRNA was expressed in 7/7 RA and 4/5 OA tissues. Cells of the synovial lining and subsynovial layer bound both antisense probes, whereas inflammatory infiltrates of RA tissues were labeled rarely. CONCLUSION: The significant number of cells in the synovium that express IGF I and II mRNA suggests a role of IGF in repair mechanisms of articular cartilage in response to injury and effects on fibroblast growth within the synovium.

Matrix metalloproteinases, but not cathepsins B, H, and L or their inhibitors in peripheral blood of patients with rheumatoid arthritis are potentially useful markers of disease activity.

OBJECTIVE: The clinical activity of rheumatoid arthritis (RA) is not reliably reflected by laboratory measures. Proteolytic enzymes involved in the cascade of joint destruction are potentially useful parameters to monitor the extent of joint inflammation in RA. This study compares the validity of two classes of proteolytic enzymes, matrix metalloproteinases (MMP) and lysosomal cysteine proteinases (cathepsin B, H, and L) as well as their respective inhibitors to serve as parameters of RA disease activity. METHODS: The proteolytic activity of cathepsin B, H, and L was determined by fluorometry in sera of 20 patients with active RA and of 20 healthy donors. In addition, the concentrations of cathepsin B and L as well as of cathepsin inhibitors stefin A, stefin B, and cystatin C were measured by ELISA. The plasma concentrations of MMP-1 (collagenase), MMP-3 (stromelysin), tissue inhibitor of metalloproteinases 1 (TIMP-1), and of MMP-1/TIMP-1 complex (MT complex) were analyzed by ELISA as well. RESULTS: A significant increase of MMP-1, MMP-3, and MT complex was observed in RA plasma, compared to normal controls, whereas TIMP-1 concentrations did not differ. In contrast, neither serum activity nor protein concentration of any of the cathepsins or cathepsin inhibitors were elevated in RA. CONCLUSION: Despite ample evidence in the literature that cathepsin activity contributes to the pathogenesis of inflammatory joint disease, this is not reflected by the conditions in peripheral blood. In contrast to the cysteine proteinases, MMP-1 and MMP-3 as well as MT complex are elevated in RA. In the context of findings in the literature, this stresses the importance of MMP as disease activity markers, compared to cysteine proteinases or their inhibitors.

Circulating levels of matrix metalloproteinases MMP-3 and MMP-1, tissue inhibitor of metalloproteinases 1 (TIMP-1), and MMP-1/TIMP-1 complex in rheumatic disease. Correlation with clinical activity of rheumatoid arthritis versus other surrogate markers.

OBJECTIVE: To investigate whether plasma levels of matrix metalloproteinases 3 (MMP-3, stromelysin), MMP-1 (collagenase), tissue inhibitor of metalloproteinases 1 (TIMP-1), and MMP1/TIMP-1 complex (MT complex) are specifically elevated in erosive joint diseases compared to nonerosive rheumatic diseases, and to assess how these markers reflect the clinical activity of rheumatoid arthritis (RA) compared to circulating cytokines and markers of connective tissue turnover as well as established variables [C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factor titer]. METHODS: Plasma levels of MMP-3, MMP-1, TIMP- 1, and MT complex were determined by ELISA. One hundred fifteen patients with RA, 20 with osteoarthritis (OA), 28 with psoriasis arthritis (PsA), 24 with ankylosing spondylitis (AS), 3 groups with systemic autoimmune diseases, and 30 healthy controls were analyzed. In patients with RA routine laboratory variables, circulating inflammatory cytokines [interleukin 1 (IL-1), tumor necrosis factor-alpha (TNF-alpha), and IL-6], collagen degradation products, and markers of bone formation were determined in parallel and were correlated to 4 variables of clinical activity. RESULTS: MMP-3 levels were markedly elevated in RA compared to controls and OA, but also in all other groups, including 26 patients with systemic lupus erythematosus (SLE). MMP-1 levels were significantly elevated in RA, but also in OA, PsA, SLE, and mixed connective tissue disease. In contrast, MT complex was elevated in RA only. TIMP-1 was not different from controls. CRP levels, MMP-3, and ESR correlated best with clinical activity of RA. In contrast, there was no correlation of IL-1 and TNF-alpha and only a weak correlation of IL-6 with clinical measures. Among variables of connective tissue turnover, only pyridinoline and deoxypyridinoline crosslinks were weakly correlated with disease activity. CONCLUSION: Elevated MMP-3 and MMP-1 levels are not specific for RA or for erosive joint diseases in general. In contrast, elevated MT complex levels were observed in patients with RA. However, the correlation of MT-1 with clinical data was weaker than that of MMP-3. Elevated MMP-3 levels reflected disease activity of RA better than cytokine levels or markers of connective tissue turnover. However, MMP-3 levels do not exceed the association of CRP with clinical activity.

Preclinical safety evaluation of the nadolol/bendroflumethiazide combination in mice, rats, and dogs.

Nadolol, a beta-adrenergic antagonist, and bendroflumethiazide, a thiazide diuretic, were administered orally alone and in combination to animals in acute and 6-month toxicity studies and in a rat teratology study. The two drugs in combination showed no evidence of potentiation of acute toxicity in mice. Nadolol and/or bendroflumethiazide were administered orally to rats at daily doses of 1000 or 160 mg/kg of nadolol and 125 or 20 mg/kg of bendroflumethiazide and to dogs at daily doses of 160 or 40 mg/kg of nadolol and 20 or 5 mg/kg of bendroflumethiazide for 6 months. The two drugs, alone and in combination, caused only minor changes in clinical-laboratory tests and no major gross or histopathologic changes. Many of the changes noted were expected pharmacologic effects of the individual agents. The drugs, alone or in combination, produced no evidence of embryotoxicity, fetotoxicity, or teratogenicity in rats. The results of these studies indicate that nadolol and bendroflumethiazide have a low order of toxicity individually, and when given in combination show no additional or potentiated toxicity.