Single oral, subcutaneous or intravenous administration to mice and rats and oral administration to dogs were performed to investigate the acute toxicity of FUT-187. 1) LD50 values in mice were 4, 395 mg/kg for males and 3, 626 mg/kg for females orally, 6, 284 mg/kg for males and 5, 492 mg/kg for females subcutaneously, and 39.4 mg/kg for males and 41.4 mg/kg for females intravenously. In rats, these values were 4, 653 mg/kg for males and 3, 761 mg/kg for females orally, 6, 799 mg/kg for males and 3, 343 mg/kg for the females subcutaneously and 21.8 mg/kg for males and 15.8 mg/kg for females intravenously. 2) Death occurred 2 hours after administration in a male dog of the 3, 000 mg/kg group just after convulsion and nasal discharge were observed. 3) General symptoms in mice and rats included a creeping gait, convulsion, singultus, cyanosis, decreased locomotor activity, piloerection and salivation which were commonly observed by all routes. All dogs showed vomiting and decreased locomotor activity; the prone or lateral position, crouching, ataxic gait and salivation were also observed in many cases. 4) On autopsy, changes attributable to local irritation by FUT-187 were seen in all species except mice and rats dosed intravenously. For the gastro intestinal-tract (GIT), inflammation of the stomach, adhesions between the stomach and the liver and sclerosis, petechiae or ulcer were observed in mice and rats dosed orally. In the subcutaneous route, retention of the test compound and necrosis at the injection site were observed. Reddening and loss of mucosal smoothness were observed in the GIT of a dog which died; desquamation, congestion, hemorrhage and retention of tested compound in the digestive mucosa were observed on histopathology.
The toxicity of FUT-187, a synthetic protease inhibitor, was investigated in Sprague-Dawley rats. FUT-187 was given orally to the rats at doses of 2, 10, 50, 250 and 1250 mg/kg/day for 13 weeks, then the drug was withdrawn for 5 weeks for recovery. The results are summarized as follows: In the 1250 mg/kg/day group, 9 out of 20 males died with decreased body weight and exhaustion. Histopathological examination revealed renal papillary necrosis, ulcer in the urinary bladder, hemostatic lesions in the lungs and liver, ulcer or erosion in the stomach, duodenum and jejunum. The surviving animals in this group showed swelling of the limbs due to synovitis, transient salivation immediately after administration, suppression of growth with decreased food consumstion. Urinalysis revealed a low pH, increased ketones and bilirubin excretion, dark yellowish change in color, the appearance of "leaflet-shaped" crystals and increased red blood cells and epithelial cells in the urinary sediment, increased water intake, decreased specific gravity and decreased sodium, potassium and chloride in the urine. Hematologically, there was an increase in the white blood cell count. A biochemical analysis of the blood revealed decreased amylase activity, glucose and total protein levels and increased GOT activity and inorganic phosphorus levels. Pathological changes were observed in the pancreas, kidney, digestive tract, urinary bladder and liver. The pancreas showed macroscopical enlargement and increased organ weight. Histopathologically, there were several alterations in the acinar cells, such as vacuolization due to increased fat droplets, nuclear irregularity, prominent nucleoli, irregular arrangement and vesiculation of rough endoplasmic reticulum (rER), dilatation of developed Golgi apparatus and increased free ribosomes. In the kidney, increased weight and pigmentation in the proximal tubular epithelium were noted. Electron microscopically, these pigments were recognized as secondary lysosomes containing filamentous material and electron dense granules within a lucent matrix. In the digestive tract, ulcer or erosion in the stomach and duodenum, and villous proliferation in the small intestine were observed. Furthermore, hyperplasia and vacuolization were noted in the mucosal epithelium of the urinary bladder. In addition, loss of perilobular fat droplets in the liver and increased adrenal weight without histological change were observed. After a 5-week recovery period, these changes disappeared almost completely. In the 250 mg/kg/day group, slight suppression of growth the appearance of "leaflet-shaped" crystals in the urinary, sediment, increased water intake and decreased sodium in the urine were observed. The pancreas showed enlargement, increased weight, acinar cell hypertrophy with increased zymogen granules, fine vacuolization, slight derangement and vesiculation of rER, and dilatation of Golgi apparatus. Also, brown pigmentation of the proximal tubular epithelium in the kidney, vacuolization of the mucosal epithelium of the urinary bladder, edematous change in the fore-stomach and villous proliferation in the duodenum, jejunum and ileum were obserbed. These changes were disappeared completely after the 5-week recovery period. In the 50 mg/kg/day group, the appearance of "leaflet-shaped" crystals in the urinary sediment, hypertrophy of the pancreatic acinar cells with increased zymogen granules, macroscopic enlargement of the pancreas and increased organ weight, and brown pigmentation of the renal proximal tubular epithelium were observed. After the recovery period, these changes disappeared completely. In the l0 and 2 mg/kg/day groups, there were no noticeable chandes in any organs examined except the pancreas, which showed acinar cell hypertrophy with increased zymogen granules in a few males.
A subacute oral toxicity study of 6-amidino-2-naphthyl 4-[(4, 5-dihydro-1H-imidazol-2-yl) amino] benzoate dimethanesulfonate (FUT-187), a new protease-inhibiting agent, was carried out in beagle dogs of both sexes. FUT-187 was administrated to dogs at daily oral doses of 15, 50 and 150 mg/kg. Dogs in 150 mg/kg group were given twice a day in a.m. and p.m.. The results were as follows; 1. Changes of physical sign attributed to FUT-187, consisted of vomiting, diarrhea, salivation, decrease of locomotor activity, sedation and hyperemia of eye mucosa. These changes expect vomiting vanished within about 2 hours after treatment. One male given 150 mg/kg died on day 19 and two females given 150 mg/kg were sacrifibed on day 55 and 67 due to deterioration of systemic conditions. 2. Body weight gain was suppressed in males given 150 mg/kg and females given 50 mg/kg or more. 3. In hematological examinations, some changes suggesting anemia or inflammation were observed in a few animals received 50 mg/kg or more 4. In serum biochemical examinations, dogs given 50 mg/kg or more had decrease of albumin, total protein, A/G ratio and total cholesterol, increase of GPT activity. In liver function test, decrease of function was observed in a few animals in l50 mg/kg group. These changes diminished by the end of recovery period. 5. In autopsy findings, ulcer formation and desquamation of mucosa in the digestive tract were observed in dead or sacrificed animals and survived animals given more than 50 mg/kg. In sacrificed animals, liver was yellow in color and intussusception was seen. 6. Plasma levels of infact FUT-187 and metabolites on the day 37 or 83 were higher than that on the first day of administration. 7. In histopathological examinations, ulcer formation, desquamation, degeneration and/or atrophy of mucosa in the digestive tract were observed in the animals from 50 mg/kg and 150 mg/kg groups. In addition, fatty deposition in hepatocytes was observed in one dead animal and two sacrificed animals. From these results, the major toxic effects attributable to FUT-187 were salivation due to its bitterness or irritation on mucosa, lesions of the digestive tract, vomiting, diarrhea and changes suggesting decrease of liver function. Based on the above, no-effect dose of FUT-187 was 15 mg/kg and the definite toxic dose was 50 mg/kg under these experimental conditions.
To assess the subacute toxicity of 6-amidino-2-naphthyl 4-[ (4, 5-dihydro-1H-imidazol-2-yl) amino] benzoate dimethanesulfonate (FUT-187) a 13 week subacute toxicity study by gavage was done in Cynomolgus monkeys at dosage levels of 0, 15, 45 and 135 mg/kg/day. Deaths were seen in the 135 mg/kg/day group; with associated debility. The animals that died had high plasma levels of FUT-l87. Little weight gain was seen in the 135 mg/kg/day group. There were no clear treatment related effects on ophthalmoscopy or electrocardiography or on hematological, biochemical or urinalysis. There were no effects noted at necropsy or on histopathology and the causes of death for each of the 3 animals that died were suppurative glomerulonephritis, bone marrow depression and possible gavage injury respectively. The no-effect level for toxicology was considered to be 45 mg/kg/day.
The chronic toxicity of FUT-187, a synthetic protease inhibitor, was investigated in Sprague-Dawley rats. FUT-187 was given orally to the rats at doses of 0.4, 2, 10, 50 and 250 mg/kg/day for 52 weeks. The drug was then withdrawn for 5 weeks. The results are summarized as follows: There were no deaths or toxic signs caused by the drug throughout the experimental period. There were no drug-related changes in food consumption, ophthalmological examination, hematology or blood chemistry. Slight suppression of growth was observed in males in the 250 mg/kg group. This change was reversed on withdrawal of the drug. Drug crystals were observed in the urinary sediments of both sexes in the 250 mg/kg group, but this change disappeared on withdrawal of the drug. Gross pathological examination revealed the following changes: enlargement and nodule formation in the pancreas in both sexes given more than 10 mg/kg of the drug; dark red spots in the glandular stomach in males in the 250 mg/kg group; thickening of the small intestinal walls in both sexes given more than 50 mg/kg. Of these organs, no changes were observed in the stomach and small intestine at the end of the recovery period. Increased pancreas weight was observed in both sexes given more than 50 mg/kg of the drug. Examination at the end of the recovery period suggested reversibility, showing a lesser degree of change. Histopathological examination revealed the following changes in the pancreatic acinar cells: acidophilic foci and nodules in both sexes given more than 10 mg/kg of the drug; adenoma in one male in the 250 mg/kg group; increased zymogen granules in both sexes given more than 50 mg/kg of drug; fine vacuolization in females in the 250 mg/kg group. At the end of the recovery period, increased zymogen granules and fine vacuolization of the acinar cells were not found. Furthermore, erosion or healed erosion in the glandular stomach, duodenum and jejunum was observed in a few males or females in the 250 mg/kg group, but those changes disappeared after the recovery period. In the liver, altered cell foci was observed more frequently in males in the 250 mg/kg group than the other groups, but this change also disappeared after the recovery period. In addition, brown pigmentation in the proximal renal tubules of the kidney was observed in both sexes in the 250 mg/kg group, but lesions observed in the examination after the recovery period were less noticeable than in the examination at the end of the administration period. Based on these results, it was concluded that the non-toxic dose was 2 mg/kg/day.
A chronic oral toxicity study of 6-amidino-2-naphthyl 4-[(4, 5-dihydro-1H-imidazol-2-yl) amino] benzoate dimethanesulfonate (FUT-187), a new protease-inhibiting agent, was carried out using male and female beagle dogs. FUT-187 was orally administered to the dogs at dose levels of 7.5, 15, 30 and 60 mg/kg/day for 52 weeks, followed by 5 weeks' recovery period. Results are summarized as follows: 1. In general conditions, vomiting, salivation and the passage of mucousy stools were observed in dogs given 15 mg/kg/day or more, and diarrhea was observed at 30 mg/kg/day or more. One male given 15 mg/kg/day showed transient pallidity of the oral mucosa, and another male in the same group showed apnea and abdominal breathing. In addition, one male given 30 mg/kg/day was euthanatized due to extreme weakness, as weight loss and pallid oral mucosa, and another male in the same group died after showing acute toxic symptoms such as hyperpnea, tonic convulsion and ataxic gait. 2. Weight gain was slightly suppressed in females given 60 mg/kg/day. No significant changes in food consumption were observed. 3. Hematological examination revealed no statistically significant changes. Decreases in RBC counts, Ht values and Hb concentrations, and increased reticulocyte counts were observed in one male of 15 mg/kg/day group, which also showed pallid oral mucosa, and in one male of the 30 mg/kg/day group, which was euthanatized in a moribund state. 4. Blood biochemistry revealed increased GPT activity in males given 15 and 30 mg/kg/day and females given 60 mg/kg/day, which was accompanied by sporadic increases in GOT, AlP and/or γ-GTP activities. Males given 30 mg/kg/day or more showed decreased total protein. 5. Hepatic function testing (ICG test) showed no statistically significant changes. One female given 60 mg/kg/day showed increased accumulating concentration of ICG. 6. There were no toxicological changes in urinalysis, fecal occult blood, renal function (PSP clearance), ophthalmological and electro-cardiographic examinations. 7. In pathological examination, inflammatory cell infiltration and microgranuloma formation in liver were noted periportally or perivenularly in both sexes given 15 mg/kg/day or more (except for 30 mg/kg/day males). In the some cases, atrophy, degeneration and necrosis of hepatocytes and/or fibrosis around inflammatory cells and microgranuloma were observed. In the spleen, one male given 15 mg/kg/day and one female given 60 mg/kg/day showed increased plasma cells in the red pulp. In the case sacrificed in a moribund condition, findings in the liver and spleen similar to those in surviving cases were detected, but were more severe, and the liver showed diffuse fibrosis. Congestive pulmonary edema was observed in one dead animal. 8. After 5 weeks' recovery period, these changes had generally disappeared, suggesting they were reversible. 9. As mentioned above, no toxic changes were observed in 7.5 mg/kg/day group, although various changes were observed in the 15 mg/kg/day or more groups in both male and female dogs. Accordingly, the non-toxic dose level of FUT-187 was estimated to be 7.5 mg/kg/day.
FUT-187 was given orally at 20, 120 and 720 mg/kg during the pre-pairing period (63 days prior to pairing in males and 14 days prior to pairing in females) and the pairing period to male and female rats and in the early stage of pregnancy (days 0 through 7 of gestation) to female rats, and the effects of the test compound on male and female reproductive performance and fetal development were evaluated. One male of the 720 mg/kg group died due to treatment. Temporary salivation was observed in males and females in the 20 mg/kg or more groups. In males, increases in the weight of the pancreas in the 120 mg/kg or more groups and the adrenals in the 720 mg/kg group, a depression of body weight gain and decreases in food intake and weight of the carcass in the 720 mg/kg group were statistically significant in comparison with controls. In females, an increase in the weight of the pancreas in the 120 mg/kg or more groups, a slight depression of body weight gain during the early stage of pregnancy and a decrease in the food intake, and a decrease in the weight of the carcass in the 720 mg/kg group were statistically significant in comparison with controls. No dose-related changes were found in the estrus, copulation, insemination and fertility indices. In fetuses, decreased numbers of corpora lutea, implantation and live fetuses were observed in the 720 mg/kg group. There were no treatment-related abnormalities in fetal mortality, sex ratio, weights of fetuses and placenta, and external and visceral examinations. Based on these results, it is concluded that the no-effect-dose levels of FUT-187 are less than 20 mg/kg for the parents, 720 mg/kg for reproductive performance and 120 mg/kg for fetal development.
6-Amidino-2-naphthyl 4-[(4, 5-dihydro-1H-imidazol-2-yl) amino] benzoate dimethanesulfonate (FUT-187) was given orally to pregnant Crj: CD (Sprague-Dawley) rats from days 7 through 17 of gestation at dose levels of 50, 200 and 800 mg/kg/day. In the 800 mg/kg/day group, salivation just after dosing, suppression in body weight gain and decreased food consumption were observed. No external, visceral and skeletal anomalies attributable to FUT-187 were observed in fetuses. From the present result, it is considered that the no-effect dose level of FUT-187 for dams and fetuses are 200 mg/kg/day and 800 mg/kg/day respectively.
A postnatal study of F1 offspring exposed to FUT-187 during fetal organogenesis was carried out using Crj: CD rat. FUT-l87 was dosed by gavage at 0, 50, 200 and 800 mg/kg/day from day 7 to 17 of gestation. All pregnant rats were allowed to deliver newborns, and F1 offspring were examined for development indices and reproduction and learning ability. Effects at 800 mg/kg included temporary salivation, body weight depression and decreased food intake. There were no adverse effects on delivery and lactation and no significant changes on neonatal development, growth, reproduction and learning ability in the F1 offspring. These results indicate that the no effect dose level of FUT-187 is 200 mg/kg/day in dams, and 800 mg/kg/day in offspring.
Oral administration of 6-amidino-2-naphthyl 4-[(4, 5-dihydro-1H-imidazol-2-yl)amino] benzoate dimethanesulfonate (FUT-187) at doses of 10, 30 and l00 mg/kg was given to New Zealand White rabbits on days 6 to 18 of gestation. The following results were obtained. Decreased food consumption and suppression of body weight gain in dams were observed and these changes contributed to the increase in aborted or prematured births and increased fetal mortality at the l00 mg/kg group. There were changed attributable to FUT-187 on external, skeletal and visceral examinations of fetuses. Based on the above, the no-effect dose level in dams and fetuses in the present study is 30 mg/kg/day.
FUT-187 was given orally at 20, 120 and 720 mg/kg to female rats during the perinatal and postnatal periods and the effect on dams and offspring were evaluated. One dam during the terminal period of gestation and 3 dams after delivery in the 720 mg/kg group died due to FUT-187. In dams, an increased pancreas weight in the 20 mg/kg or more groups, temporary salivation after dosing in the 120 mg/kg or more groups, and a depression of body weight gain and decreased food intake and weight of the carcass in the 720 mg/kg group were statistically significant in comparison with controls. In offspring, postnatal death rate in the 720 mg/kg group tended to increased. Decreased body weight gain and delayed appearence of abdominal hair and descent of testis in the 720 mg/kg group were statistically significant in comparison with controls. There were no treatment-related abnormalities in visceral examination, organ weight, skeletal examination, sensory function, behavioral function, learning ability or reproductive function. Based on these results, it is concluded that the no-effect-dose levels of FUT-187 are less than 20 mg/kg for dams, and 120 mg/kg for reproductive performance of dams and offspring development.
Antigenicity study of 6-amidino-2-naphthyl 4-[(4, 5-dihydro-1H-imidazol-2-yl) amino] benzoate dimethanesulfonate (FUT-187), a new protease inhibitor, was investigated in guinea pigs and mice and the following results were obtained. 1. In guinea pigs immunized with FUT-187 plus adjuvant by intramuscular / subcutaneous routes, ASA, ACA and PCA reactions challenged intraveneously or intradermally were positive. 2. In guinea pigs immunized with FUT-187 plus adjuvant by intramuscular / subcutaneous routes, ASA and PCA reactions challenged orally were negative. 3. In guinea pigs immunized with FUT-187 by the oral route, ASA, ACA and PCA reactions were negative. 4. In guinea pigs immunized with IABA and AN plus adjuvant by intramuscular / subcutaneous routes, ASA and PCA reactions were negative. 5. 48-hr PCA reactions were elicited with sera obtained from BALB / c and C3H / He mice immunized with FUT-187 plus adjuvant by the intraperitoneal route, responses were negative. 6. From the results of hapten inhibition tests using anti-FUT-187 guinea pig serum, it is suggested that the antigenicity of FUT-187 is attributable to the its benzoic acid.