Registration Dossier

Administrative data

Endpoint:
basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
21 Apr 2003 - 18 Feb 2005
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2005
Report date:
2005

Materials and methods

Objective of study:
absorption
metabolism
toxicokinetics
Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 417 (Toxicokinetics)
Deviations:
no
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
(5-hydroxy-1,3-dimethyl-1H-pyrazol-4-yl)[2-(methylsulfonyl)-4-(trifluoromethyl)phenyl]methanone
EC Number:
609-256-3
Cas Number:
365400-11-9
Molecular formula:
C14H13F3N2O4S
IUPAC Name:
(5-hydroxy-1,3-dimethyl-1H-pyrazol-4-yl)[2-(methylsulfonyl)-4-(trifluoromethyl)phenyl]methanone
Specific details on test material used for the study:
RADIOLABELLING INFORMATION
[Phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone for dose preparation of the oral low dose experiment (O-LDE-M)
- Radiochemical purity: 97.6%
- Specific activity: 28.6 mCi/mmol
- Locations of the label: phenyl ring

[Pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone for dose preparation of the oral low dose experiment (O-LDE-M)
- Radiochemical purity: 98.4%
- Specific activity: 55.3 mCi/mmol
- Locations of the label: pyrazole position 3

[Phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone for dose preparation of the intravenous low dose experiment (IV-LDE-M)
- Radiochemical purity: 100%
- Specific activity: 28.6 mCi/mmol
- Locations of the label: phenyl ring

[Pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone for dose preparation of the intravenous low dose experiment (IV-LDE-M)
- Radiochemical purity: 100%
- Specific activity: 54.2 mCi/mmol
- Locations of the label: pyrazole position 3

Radiolabelling:
yes

Test animals

Species:
rat
Strain:
Wistar
Details on species / strain selection:
no data provided
Sex:
male
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories (Raleigh, NC, USA)
- Age at study initiation: approximately 9 weeks
- Weight at study initiation: for oral experiments: 188 - 225 g, for intravenous experiments: 193 - 250 g
- Housing: following dosing, rats were housed individually in Nalgene rodent metabolism cages which allowed collection of urine, feces, and respired 14CO2 and volatile metabolites
- Diet: Certified Rodent Diet 5002 Meal (PMI Nutrition International, St. Louis, USA), ad libitum
- Water: not further specified, ad libitum
- Acclimation period: 6 - 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22
- Humidity (%): 50 - 58
- Photoperiod (hrs dark / hrs light):12/12

Administration / exposure

Route of administration:
other: oral or intravenous
Vehicle:
other: oral formulation: water; intravenous formulation: 0.9% sodium chloride
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:

[Phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone Oral Dose Experiment (O-LDE-M)
A 0.2-mL aliquot of the [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone stock solution was transferred into a 5-mL volumetric flask, and the aliquot was diluted to 5 mL with acetonitrile (ACN). The solution was radioassayed and concentrated slightly using a stream of nitrogen gas. An additional aliquot (0.03 mL) of the [phenyl-UL-14C] AE 0317309 stock solution was transferred into the 5-mL volumetric flask, and the solution was diluted to 5 mL with ACN. The solution was radioassayed and transferred to a 50-mL pear-shaped flask. A nonradioactive test substance stock solution was prepared by transferring 65.5 mg of nonradioactive test substance (K-1196) into a 10-mL volumetric flask and diluting the contents to mark with ACN. A 1.77-mL aliquot of the nonradioactive test substance stock solution was transferred to the 50-mL pear-shaped flask. The sample was concentrated to dryness at 30 to 35°C using a rotary evaporator (Büchi; Westbury, NY). The sample was transferred to a 10-mL, graduated mixing cylinder using multiple 1-mL rinses with H2O, and the sample was diluted to 7.0 mL with H2O. The dose solution was mixed, radioassayed (0.056 mCi/mL; 8.54 mCi/mmol; 2.37 mg/mL), and aliquots were analyzed by HPLC and mass spectrometry.

[Pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone Oral Dose Experiment (O-LDE-M)
A 0.2-mL aliquot of the [pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone stock solution was transferred into a 10-mL volumetric flask, and the aliquot was diluted to 10 mL with ACN. The solution was radioassayed and transferred to a 50-mL pear-shaped flask. A nonradioactive test substance stock solution was prepared by transferring 72.4 mg of nonradioactive test substance (K-1196) into a 10-mL volumetric flask and diluting the contents to mark with ACN. A 1.87-mL aliquot of the nonradioactive test substance stock solution was transferred to the 50-mL pear-shaped flask. The sample was concentrated to dryness at 30 to 35°C using a rotary evaporator. The sample was transferred to a 10-mL, Reacti-Vial reaction vial (Pierce; Rockford, IL) containing a magnetic stir bar, using multiple 1-mL rinses with H2O, and the sample was diluted to 7.0 mL with H2O. The dose solution was stirred, radioassayed (0.054 mCi/mL; 8.72 mCi/mmol; 2.26 mg/mL), and aliquots were analyzed by HPLC and mass spectrometry.

[Phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone Intravenous Experiment (IV-LDE-M)
A 3.6-mL aliquot of the [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone stock solution (C-938B) was transferred into a 10-mL volumetric flask, and the aliquot was diluted to 10 mL with ACN. The solution was radioassayed and concentrated slightly using a stream of nitrogen gas. An additional aliquot (1.0-mL) of the [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone stock solution was transferred into the 10-mL volumetric flask, and the solution was diluted to 10 mL with ACN. The solution was radioassayed and transferred to a 50-mL pear-shaped flask. A nonradioactive test substance stock solution was prepared by transferring 65.0 mg of nonradioactive test substance (K-1267) into a 10-mL volumetric flask and diluting the contents to mark with ACN. A 1.90-mL aliquot of the nonradioactive test substance stock solution was transferred to the 50-mL pear-shaped flask. The sample was concentrated to dryness at 30 to 35°C using a rotary evaporator. The sample was transferred to a 10-mL, Reacti-Vial reaction vial containing a magnetic stir bar, using multiple 1-mL rinses with saline solution, and the sample was diluted to 8.3 mL with saline solution. The dose solution was stirred, radioassayed, and filtered using a syringe filter (0.22 μm). The filtered dose solution was mixed and radioassayed (0.063 mCi/mL; 10.0 mCi/mmol; 2.29 mg/mL), and aliquots were analyzed by HPLC and mass spectrometry.

[Pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone Intravenous Experiment (IV-LDE-M)
A 3.0-mL aliquot of the [pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone stock solution (C-1024A) was transferred into a 10-mL volumetric flask, and the aliquot was diluted to 10 mL with ACN. The solution was radioassayed and transferred to a 50-mL pear-shaped flask. A 12.8 mg aliquot of nonradioactive test substance (K-1267) was transferred to the 50-mL pear-shaped flask. The sample was mixed and concentrated to dryness at 30 to 35°C using a rotary evaporator. The sample was transferred to a 10-mL, Reacti-Vial reaction vial containing a magnetic stir bar, using multiple 1-mL rinses with saline solution, and the sample was diluted to 7.1 mL with saline solution. The dose solution was stirred, radioassayed and filtered using a syringe filter. The filtered dose solution was stirred and radioassayed (0.062 mCi/mL; 9.97 mCi/mmol; 2.24 mg/mL), and aliquots were analyzed by HPLC and mass spectrometry.
Duration and frequency of treatment / exposure:
single administration
Doses / concentrationsopen allclose all
Dose / conc.:
10 other: mg/kg bw
Remarks:
oral dose of [phenyl-UL-14C] AE 0317309
Dose / conc.:
9.81 other: mg/kg bw
Remarks:
intravenous dose of [phenyl-UL-14C] AE 0317309
Dose / conc.:
9.88 other: mg/kg bw
Remarks:
oral dose of [pyrazole-3-14C] AE 0317309
Dose / conc.:
9.6 other: mg/kg bw
Remarks:
intravenous dose of [pyrazole-3-14C] AE 0317309
No. of animals per sex per dose / concentration:
5 males per radiolabel (oral administration)
4 - 5 males per radiolabel (intravenous administration)
Control animals:
no
Details on dosing and sampling:
PHARMACOKINETIC STUDY (Absorption, distribution, excretion)
- Tissues and body fluids sampled: urine, faeces, blood, tissues (bone, brain, fat, heart, kidney, liver, lung, muscle, skin, spleen, testes, and thyroid), cage washes
- Time and frequency of sampling:
urine: 6, 12, 24 and 48 hours post-treatment (in the [phenyl-UL-14C] AE 0317309 oral experiment also after 52 hours)
faeces: at 24-hour intervals until sacrifice (in the [phenyl-UL-14C] AE 0317309 oral experiment also after 52 hours)
blood and tissues: at sacrifice (in general 48 hours post-treatment; 52 hours in the [phenyl-UL-14C] AE 0317309 oral experiment)

METABOLITE CHARACTERISATION STUDIES
- Tissues and body fluids sampled: urine, faeces
- Time and frequency of sampling:
urine: 6, 12, 24 and 48 hours post-treatment (in the [phenyl-UL-14C] AE 0317309 oral experiment also after 52 hours)
faeces: at 24-hour intervals until sacrifice (in the [phenyl-UL-14C] AE 0317309 oral experiment also after 52 hours)
- From how many animals: 4-5 (pooled samples)
- Method type(s) for identification: radioassay and HPLC-MS-MS

Results and discussion

Preliminary studies:
A preliminary experiment was conducted in which male and female rats were administered a single oral dose of [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone at a rate of 100 mg/kg bw. In this preliminary experiment, the [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone was well absorbed, with absorption of approximately 91% of the administered dose for the females and 88% for the males. The elimination of the [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone was very rapid, with the majority of the administered dose being excreted via urine during the first 24 hours following dosing for both male and female rats.
Radioactivity in the tissues was below 0.5% of the administered dose for both sexes at 72 hours after the administration. 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone was observed as the major radioactive component in the urine and feces, representing approximately 82% and 89% of the total excreted radioactivity in males and females, respectively.
Main ADME resultsopen allclose all
Type:
absorption
Results:
The test substance was readily absorbed with 57 - 62% of the dose recovered in urine within 6 hours and 73 and 75% within 52 and 48 hours, respectively.
Type:
distribution
Results:
≤ 2% of the administered dose remained in the carcass and tissues at sacrifice. Residue levels were highest in liver and kidney.
Type:
metabolism
Results:
87 - 95% was excreted unchanged; three minor metabolites were indentified in urine and faeces. The major metabolic pathway occurred via N-demethylation of the test substance.
Type:
excretion
Results:
Total excretion was rapid, > 96% was excreted within 24 hours (approx. 90% in the urine, 10% in the faeces)

Toxicokinetic / pharmacokinetic studies

Details on absorption:
[Phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone:
The [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone was readily absorbed following oral administration, with 62% of the dose recovered in the urine within 6 hours and a total of 73% of the dose recovered in the urine at the time of sacrifice (52 hours). The intravenous experiment showed that 10% of the dose was found in the feces at the time of sacrifice (48 hours).

[Pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone:
The [pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone was readily absorbed following oral administration with 57% of the dose recovered in the urine within 6 hours and a total of 75% of the dose recovered in the urine at the time of sacrifice (48 hours). The intravenous experiment showed that 8% of the dose was found in the feces at the time of sacrifice (48 hours).
Details on distribution in tissues:
In all experiments, ≤ 2% of the administered dose remained in the carcass and tissues at sacrifice. In all experiments, the highest residues were found in the liver and kidney.
Details on excretion:
[Phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone - oral experiment
The distribution of [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone residues among urine, feces, cage wash, and tissues for each rat in the [phenyl-UL-14C] AE 0317309 O-LDE-M experiment is shown in Table 1. Following oral dosing, [phenyl-UL-14C] AE 0317309 residues were rapidly excreted (102% of the administered dose was excreted within 24 hours). The total radioactive recovery was 108% of the administered dose. The majority of the radioactivity was excreted in the urine (73%), with less being excreted in the feces (31%). Much of the administered dose was rapidly excreted in the urine within 6 hours of dosing (62%).

[Pyrazole-3-14C] AE 0317309 - oral experiment
The distribution of [pyrazole-3-14C] AE 0317309 residues among urine, feces, cage wash, and tissues for each rat in the [pyrazole-3-14C] AE 0317309 O-LDE-M experiment is shown in Table 1. Following oral dosing, [pyrazole-3-14C] AE 0317309 residues were rapidly excreted (106% of the administered dose was excreted within 24 hours). The total radioactive recovery was 111% of the administered dose. The majority of the radioactivity was excreted in the urine (75%), with less being excreted in the feces (32%). Much of the administered dose was rapidly excreted in the urine within 6 hours of dosing (57%).

[Phenyl-UL-14C] AE 0317309 - intravenous experiment
The distribution of [phenyl-UL-14C] AE 0317309 residues among urine, feces, cage wash, and tissues for each rat in the [phenyl-UL-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone IV-LDE-M experiment is shown in Table 1. Following intravenous dosing, [phenyl-UL-14C]5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone residues were rapidly excreted (96% of the administered dose was excreted within 24 hours). The total radioactive recovery was 100% of the administered dose. The majority of the radioactivity was excreted in the urine (87%), with less being excreted in the feces (10%). Much of the administered dose was rapidly excreted in the urine within 6 hours of dosing (83%).

[Pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone - intravenous experiment
The distribution of [pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone residues among urine, feces, cage wash, and tissues for each rat in the [pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone IV-LDE-M experiment is shown in Table 1. Following intravenous dosing, [pyrazole-3-14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone residues were rapidly excreted (97% of the administered dose was excreted within 24 hours). The total radioactive recovery was 106% of the administered dose. The majority of the radioactivity was excreted in the urine (91%), with less being excreted in the feces (8%). Much of the administered dose was rapidly excreted in the urine within 6 hours of dosing (84%).

Metabolite characterisation studies

Metabolites identified:
yes
Remarks:
, 3 minor metabolites were identified
Details on metabolites:
All individual residues which accounted for ≥ 5% of the administered dose were identified; additionally, some components that were present in smaller quantities were also identified. Identification of the residues was accomplished by comparison of the mass spectral data to that of authentic reference standards when available. Some residues were tentatively identified by comparison of their HPLC retention times with those of authentic reference standards or components which had been identified in other matrices.

The total amount of hydroxymethyl (5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone identified in the urine and feces from both oral experiments was 2% of the administered dose. The total amount of hydroxymethyl (5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone identified in the urine and feces from both intravenous experiments was 1 - 2% of the administered dose.

The total amount of desmethyl (5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone identified in the urine and feces from both oral experiments was 8% of the administered dose. The total amount of desmethyl (5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone identified in the urine and feces from both intravenous experiments was 6% of the administered dose.

The total amount of AE B197555 identified in the urine and feces from the [phenyl-UL-14C] oral and intravenous experiment was 1% of the administered dose.

From all experiments, 87 to 95% of the administered dose was excreted unchanged as (5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone. Hydroxymethyl (5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone, desmethyl 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone, and AE B197555 were observed as minor metabolites in the urine and feces. Greater than 96% of the administered dose in each experiment was identified. The major metabolic pathway occurred via N-demethylation of the test substance.

Any other information on results incl. tables

Table 1: Recovery of radioactivity in tissues and excreta of rats after administration of [14C] 5-hydroxy-1,3-dimethylpyrazol-4-yl)(α,α,α-trifluoro-2-mesyl-p-tolyl)methanone.

 

Percent of Radioactive Dose Recovered (%)

 

[Phenyl-UL-14C]

p.o.

[Pyrazole-3-14C]

p.o.

[Phenyl-UL-14C]

i.v.

[Pyrazole-3-14C]

i.v.

Expired air

< 0.1

< 0.1

n.a.

n.a.

Tissues

1.0

1.0

0.8

1.0

Carcass

0.1

0.2

0.4

0.8

Cage wash

2.3

2.5

2.0

3.1

Urine

 

 

 

 

     0 to 6 hour

62.5

56.8

82.7

84.1

    6 to 12 hour

8.2

15.2

1.8

3.6

  12 to 24 hour

1.3

2.5

1.5

1.8

  24 to 48 hour

1.1

0.5

0.7

1.2

  48 to 52 hour

0.1

n.a.

n.a.

n.a.

 Total for urine

73.1

74.9

86.6

90.7

Feces

 

 

 

 

  0 to 24 hour

30.0

31.1

9.6

7.4

  24 to 48 hour

1.2

0.8

0.8

0.6

  48 to 52 hour

< 0.1

n.a.

n.a.

n.a.

  Total faeces

31.2

32.0

10.4

8.0

Total

108

111

100

106

p.o.   per os                 i.v. intravenously n.a.  not applicable

 

Applicant's summary and conclusion