Registration Dossier

Administrative data

Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report Date:
1995

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity in Rodents)
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Specific details on test material used for the study:
Compound number: CJ-11,972-27
Lot number: 32,372-136-2
Active moiety: 82.2%
Storage conditions: Bulk was stored at room temperature in an amber bottle wrapped in foil.

Test animals

Species:
rat
Strain:
Sprague-Dawley
Details on species / strain selection:
The rat is our standard small animal test species and is generally accepted as a test
species in toxicity studies. A previous study in rats has demonstrated systemic
exposure following the oral administration of CJ-11,972-27.
Sex:
male/female
Details on test animals and environmental conditions:
Rats [Crl:CD®(SD)BR VAF/Plus®] supplied by Charles River Breeding Laboratories
(Raleigh, NC} were used in this study. A total of 66 males and 66 females were
acclimatized to our laboratory for approximately 3 weeks prior to dosing. From these,
60 males and 60 females were randomly assigned to 4 groups of 15 per sex per group.
Animals were randomized according to body weight using an on-line computer program.
At treatment initiation, individual body weights ranged from approximately 210.5 to
295.9 g for males and 150.2 to 225.4 g for females (approximately 55-56 days old, both
sexes}. ·
Each rat was identified by an individual animal number tattooed on the tail. Each cage
was labeled with the study animal number, pretest animal number, control or compound
number where appropriate, study number, cage number, sex, species, route and dose
group/level on a color coded card. For convenience, consecutive animal numbers were
assigned to the rats at randomization and are used in this report to identify individual
animals.

The rats were housed individually in hanging stainless steel cages in a single room
dedicated to this study. Room environmental conditions had design specifications as
follows: 18 air changes per hour with air filtered through 85-90% efficiency filters and
then through HEPA filters, relative humidity of 50 ± 5%, temperature of 70 ± 2F and a
12 hour light/dark cycle.
Agway PROLAB RMH 3200 certified rodent diet and municipal drinking water, further
purified by reverse osmosis were provided ad libitum. Fresh diet was presented weekly
or more frequently, if required. To the best of our knowledge, there were no
contaminants in the diet or water that could be expected to interfere with the outcome of
this study.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: 0.01M citrate buffer
Details on oral exposure:
Solutions of CJ-11,972-27 were prepared daily for the first two weeks of the study, then
at least once weekly for the remainder of the dosing period. The appropriate amount of
compound was weighed out and placed in an appropriate size glass container. The
sample was then stirred in the required amount of the vehicle (0.01 M citrate buffer) until
the solid CJ-11,972-27 was dissolved. The pH of each dosing solution was determined.
The dosing solutions were covered with aluminum foil and parafilm and stored in a
cabinet away from light at room temperature.
The vehicle, 0.01 M citrate buffer, was also prepared at least once weekly. The
appropriate amount of sodium citrate was weighed out and dissolved in the required
volume of deionized water. The same procedure was followed with citric acid. These
two solutions were then mixed, citric acid:sodium citrate in an approximately 4:1 ratio.
The pH was determined on the resulting solution. The pH ranges for both vehicle and
drug dosing solutions were within the 3.0 to 4.0 range throughout the treatment period.

CJ-11,972-27 was administered orally by gavage once daily using a dosing volume of
1 O ml/kg. Controls were dosed. with vehicle in the same manner.
Analytical verification of doses or concentrations:
no
Duration of treatment / exposure:
All rats were dosed for 3 months (93-95 days).
Frequency of treatment:
daily
Doses / concentrationsopen allclose all
Dose / conc.:
0 mg/kg bw/day (nominal)
Dose / conc.:
5 mg/kg bw/day (nominal)
Dose / conc.:
30 mg/kg bw/day (nominal)
Dose / conc.:
150 mg/kg bw/day (nominal)
No. of animals per sex per dose:
15 per sex per dose

Examinations

Observations and examinations performed and frequency:
Clinical observations/measurements

Mortality/ Appearance/Behavior
All rats were observed at least 5 times daily (3 times on weekends and holidays) in their
· cages for signs of toxicity and any changes in appearance or behavior.

Body weight
Body weights were determined weekly during the study period. Pre-study body weights
were collected -19, -17 and -7 days prior to the initiation of dosing, and again on day 1
prior to dosing.

Food consumption
Food consumption was measured weekly during the study period taking into account
losses of the diet as a result of spillage by the animals. A preliminary food consumption
was determined 1 week prior to treatment initiation and again on day 1 prior to dosing.
Animals were fasted during urine collection and overnight prior to clinical pathology
workups.

Ophthalmology
Ophthalmoscopic examinations were performed once prior to treatment initiation and on
day 79 (males) and day 80 (females). To facilitate the examination, mydriasis was
induced by 1.0% tropicamide (Mydriacyl®, Alcon Laboratories). A naked eye exam was
performed prior to instilling the mydriatic.

Clinical laboratory measurements

Sample collection
Blood samples for hematology and serum chemistry determinations were collected by
retro-orbital sinus puncture from all rats once prior to treatment initiation and during
weeks 6 and 13. Animals were bled in a fasted state. Urine was collected for urinalysis
once prior to treatment initiation and during weeks 6 and 13. The urine collection period
was approximately 6 hours. Animals were fasted during this time and did not have
access to water. Additionally, fecal samples were obtained from all animals prior to
treatment initiation and during weeks 6, 13 and 14 for the determination of fecal occult
blood using Hemoccult® slides. The following measurements were made:
Hematology
The following parameters were measured on the Technicon H*1, Hematrak 590 or the
Electra 700 (MLA):
red blood cell count (RSC, x10e6/mm^3)
hemoglobin concentration (HGB, g/dl)
hematocrit (HCT, %)
white blood cell count (WBC, x10^3/mm^3)
white blood cell differential count (WBC Differential,%)
N = neutrophils
L = lymphocytes
MO = monocytes
EO = eosinophils
B = basophils
LUC = large unclassified cells
platelet count (PLT, x10^3/mm^3)

fibrinogen (FIBR, mg/di) (Manual)

Mean corpuscular volume (MCV, fl), mean corpuscular hemoglobin (MCH, µµg) and
mean corpuscular hemoglobin concentration (MCHC, %) are calculated values.
Absolute WBC differential counts (NCT, LCT, MOCT, EOCT, BCT, LUCT, /mm^3)
arecalculated from the WBC and WBC differential.

Serum chemistry
The following assays were conducted on either the Hitachi or COBAS-810 instruments:
sodium (NA, meq/1)
potassium (K, meq/1)
calcium (CA, mg/di)
chloride (CL, meq/1)
urea nitrogen (BUN, mg/di)
alanine aminotransferase (ALT, U/L)
aspartate aminotransferase (AST, U/L)
sorbitol dehydrogenase (SDH, U/L)
total protein (TP, g/dl)
albumin (ALBM, g/dl)
5'nucleotidase (5'NT, U/L)
triglycerides (TRIG, mg/di)
glucose (GLUC, mg/di)
cholesterol (CHOL, mg/di)
bile acids (BILA, umole/1)
creatinine (CREA, mg/di)
Globulin (GLOB, g/dl) and albumin/globulin ratios (AG) were calculated.

Urinalysis
The following measurements were conducted on the CLINITEK 200 unless otherwise indicated:
volume (VOL, ml, manual)
specific gravity (SPGR, refrac.)
pH (5 to 9)
protein (PRO, neg to 4+)
blood (BLO, neg to 3+)
glucose (Glu, neg to 4+)
urobilinogen (URO, neg to 4+)
bilirubin (BIL, neg to 3+)
ketones (KET, neg to 4+)
Color (COLA, visual assessment)
Fecal samples were collected for the detection of occult blood (FOB, Hemoccult®).
Sacrifice and pathology:
Postmortem observations
Necropsy
All surviving rats were fasted overnight, anesthetized by an intraperitoneal injection of
pentobarbital sodium and exsanguinated on days 94, 95 or 96. Following an external
and visual examination, samples of the organs listed below plus a sample of any gross
lesion were placed in fixative.

adrenal glands
brain (cerebrum, cerebellum
and pons)
cecum
colon
duodenum
epididymides*
esophagus
eyes
Harderian gland
heart
ileum
jejunum
kidneys
liver (left and right lateral lobes)
lung (both diaphragmatic lobes)
mesenterlc lymph node
ovaries
pancreas
parathyroid
pituitary gland
prostate
salivary gland
seminal vesicle
skin and adnexa
spinal cord (cervical)
spleen
sternum (bone and marrow)
stomach
testes (both)
thymus
thyroid gland
trachea
urinary bladder
uterine horns
vagina
*Note: The right epididymis was used for seminal analysis in surviving males.

Organ weights
Body weights and the weights of the kidneys, liver, heart, brain, adrenals and testes
were recorded and organ to body weight ratios calculated.
Other examinations:
Seminal Analysis
Whole epididymides were weighed individually from all surviving male rats at necropsy.
Caudae epididymides were collected for analysis of sperm count and sperm motility.
For sperm count, right caudae were weighed, frozen on dry ice, stored at -80 C, and
processed for manual counting of sperm with .a hemacytometer. Sperm counts are
expressed as the number per gram of caudal epididymal tissue. For sperm motility, the
tunicae of the left caudae were individually pierced with a scalpel, allowing dispersion of
sperm into warmed medium for approximately 5 minutes. Percent motility of each
diluted sample was quantified by a Hamilton-Thorn IVOS Version 1 O Motility Analyzer.
Statistical significance of the data was evaluated for the presence of a dose-related
trend using a linear contrast.

Tiss�e processing
Eyes and ,Harderian glands were collected and preserved in 3% glutaraldehyde in
sorenscn's Buffer. Testes and left epididymides were collected and fixed in Bouins. All
other orqans/tissues and macroscopic lesions were collected and fixed in 10% neutral
buffere:1 tormalln. Following fixation, tissues were trimmed, dehydrated, embedded in
paraffin, sectioned, and mounted on glass slides and stained with hematoxylin and
eosin. Selected special stains (Oll-Bed-O and PAS) were also employed in arriving at
some diagnoses.
!vi icroscopic examination
The processed tissues listed above and gross lesions of all rats in the high dose and
control grdups were examined by light microscopy, and the results recorded utlllzinq an
on-line computer program. Liver, lung, thyroid, and any gross lesions from low and
intermediate group animals were also examined.
Following;completion of the tissue evaluation by the study pathologist, a second
pathologist performed a peer evaluation. The histopathology, as presented in this
report, is the consensus of the study and peer review pathologists.·
Statistics:
The following parameters were analyzed statistically: body weight, food consurnpnon,
. clinical pathology and organ weights. Statistical analyses were perfonned separately· for
males andl females as follows: For each collection period, each treated group mean
was compared with the control group mean. Dunnett's multiple comparison
procedure was used if a preliminary Bartlett's test for variance homogeneity was not
signlficant at the a=0.05 level. If there was significant variance heterogeneity, the
cochran-cox modified t-test was used for comparison between treated and control
group means. Statistical significance of the comparisons was indicated at both the
a=0.05 and 0.01 levels.
For hepatic microsomal enzyme data, statistical comparisons between vehicle control
means and sample means from animals given CJ-11,972-27 were completed using the
"compare" program of RS/1 (release 4.3.1, Bolt Beranek & Newman Inc.).
For the purpose of data interpretation, statistical significance was not considered to
automatically imply toxicological significance. Conversely, the absence of a statistically
significant comparison was not considered to imply the lack of a biologically important
effect.
1. Dunnett, C. W. (1955). A Multiple comparison Procedure for Seveiral
Treatments with a Control. Journal American Statistics Association. 50,
1096-1121.
2. Dunnett, C.W. (1964). New Tables for Multiple Comparisons with a Control.
Biometrics. 20, pp. 402-492.
3. Sokal, R. and Rohlf, F.J. (1969). Biometry. W.H. Freeman and Co., San
Francisco.
4. Cochran, W.G. and Cox, G.M. (1959). Experimental Designs. John Wiley,
New York.

Results and discussion

Results of examinations

Clinical signs:
effects observed, treatment-related
Description (incidence and severity):
Predominant clinical signs observed at both 30 and 150 mg/kg/day included salivation
and raspy breathing. Salivation generally occurred immediately after dosing and
subsided within 1 - 4 hours post-dose. Raspy breathing in the 150 mg/kg/day dose
group (nearly half to all of the animals affected/week) was first observed immediately
post-dose on day 1 and generally continued until the next day. At 30 mg/kg/day (nearly
a third to all affected/week), this sign was first observed after dosing on day 2 and
generally subsided by the end of each dosing day. Transient and very minor incidents
of salivation and raspy breathing (nearly a tenth to a third affected/week) were also
apparent at 5 mg/kg/day, which also generally subsided by the end of each dosing day.
Urogenital staining was observed during the treatment period, primarily in
150 mg/kg/day females. Sporadic or transient observations of unkempt appearance and
labored breathing were also prominent in some 150 mg/kg/day animals. Head tremors
were also noted in one 150 mg/kg/day male (#95) at approximately 4-6 hours post-dose
on days 24 and 25.
Alopecia was observed among animals in both control and drug-treated groups during
the treatment period. These changes were not considered to be treatment-related due
to their sporadic occurrence and the lack of a consistent relationship with dose or
duration of treatment.
Mortality:
mortality observed, treatment-related
Description (incidence):
All but seven animals survived the 93-day dosing period. Four 150 mg/kg/day animals
died within the first 44 days of dosing (male #'s 101, 102, 104; female #119), while one
150 mg/kg/day female (#116) was found dead on day 84. One 30 mg/kg/day female
(#78) was sacrificed in moribund condition on day 25. The deaths of female #'s 78 and
119 were attributed to complications from gavage dosing trauma, while the remaining
four deaths at 150 mg/kg/day (#'s 101, 102, 104, 116) were considered to be treatment­
related. Most of these drug-treated animals showed an unkempt appearance,
salivation, raspy breathing, urogenital staining, and body weight loss prior to death or
unscheduled sacrifice. One control male (#14) was sacrificed in moribund condition on
day 82 and was later diagnosed with malignant lymphoma.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
Body weight and food consumption were unaffected at 5 mg/kg/day. Mean body weight
gains at 30 mg/kg/day were slightly lower ( 11-12%) when compared to controls. Mean
body weight gains in the 150 mg/kg/day male and female dose groups were 47% and
21% lower, respectively. Transient decreases in food consumption were noted at
150 mg/kg/day in both sexes on day 8. Persistent depressions in food consumption
were only noted in 150 mg/kg/day males during the remaining treatment period.
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
see above
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
no effects observed
Haematological findings:
effects observed, treatment-related
Description (incidence and severity):
Treatment-related changes in hematology parameters consisted of slightly higher group
mean neutrophil counts at 30 and 150 mg/kg/day (1.41 - 2.16X control, both sexes).,
Other occasional differences in mean hematology parameters that achieved statistical
significance were not considered to be treatment-related due to either their small
magnitude, sporadic occurrence, or the lack of a consistent relationship with dose or
duration of treatment.
Clinical biochemistry findings:
effects observed, treatment-related
Description (incidence and severity):
Changes in group mean serum chemistry parameters were apparent at 30 and
150 mg/kg/day but not at 5 mg/kg/day when compared to controls. These changes
were generally observed on both study days that serum chemistries were assessed
(days 37 and 86). The 150 mg/kg/day dose group of both sexes showed slightly
elevated 5' nucleotidase (1.4 - 2.2X control) and alanine aminotransferase (1.3 - 1.6X
control) activities. Serum cholesterol was slightly higher at 30 and 150 mg/kg/day in
females (1.3 - 2.3X control) and at 150 mg/kg/day in males (1.3X control). Serum
triglycerides were also slightly lower at 150 mg/kg/day in males (0.4 - 0.7X control) .
Total protein, albumin, globulin and fibrinogen were slightly higher (1.1 - 1.3X control) at
150 mg/kg/day in females. The slightly higher mean values for blood urea nitrogen (1.2
- 1.4X control) and serum creatinine (1.1 X control) in the 150 mg/kg/day female dose
group were due to higher values reported for one female (#112). No corresponding
gross or microscopic renal lesions were observed in this animal.
Other occasional differences in mean serum chemistry parameters that achieved
statistical significance were not considered to be treatment-related due to either their
small magnitude, sporadic occurrence, or the lack of a consistent relationship with dose
or duration of treatment.
Urinalysis findings:
no effects observed
Description (incidence and severity):
females (1.3 - 2.3X control) and at 150 mg/kg/day in males (1.3X control). Serum
triglycerides were also slightly lower at 150 mg/kg/day in males (0.4 - 0.7X control) .
.,,--- " .
Total protein, albumin, globulin and fibri�were slightly higher (1.1 - 1.3X control) at
150 mg/kg/day in females. The slightlynigller mean values for blood urea nitrogen (1.2
- 1.4X control) and serum creatinine (1.1 X control) in the 150 mg/kg/day female dose
group were due to higher values reported for one female (#112). No corresponding
gross or microscopic renal lesions were observed in this animal.
Other occasional differences in mean serum chemistry parameters that achieved
statistical significance were not considered to be treatment-related due to either their
small magnitude, sporadic occurrence, or the lack of a consistent relationship with dose
or duration of treatment.
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Description (incidence and severity):
Group mean relative liver weights were higher at 150 mg/kg/day in males and females
(1.5X and 1.8X control, respectively), due to increases in absolute liver weight (1.2X and
1.7X control, respectively). Mean relative liver weight was also slightly higher at
30 mg/kg/day in females (1.1 X control). ·
Mean absolute and relative adrenal weights were slightly higher at 150 mg/kg/day (1.2 -
1 .3X control) in females. The slightly higher mean relative weights of various other
organs (kidney, adrenal, brain, heart, testis, epididymis) noted in 150 mg/kg/day males
were attributed to decreased body weights at necropsy.
Gross pathological findings:
effects observed, non-treatment-related
Description (incidence and severity):
Focal red pulmonary discoloration was noted in one 30 mg/kg/day female (#78) and five
150 mg/kg/day animals (#s 97, 100, 102, 104, 110). This change correlated
microscopically with aspiration-induced bronchopneumonia in all but one of the affected
150 mg/kg/day males (#97).
Necropsy findings attributed to gavage dosing trauma were confined to one
30 mg/kg/day female (#78) and one 150 mg/kg/day female {#119) which either died or
was sacrificed in moribund condition during the study. These changes consisted of
periesophageal and axillary masses or swelling which correlated microscopically with
abscesses or edema.
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
Treatment-related microscopic findings were confined to the lungs of 30 and
150 mg/kg/day animals and the liver of 150 mg/kg/day animals.
Pulmonary foam cell foci were noted in 150 mg/kg/day males (8 of 15) and females (7 of
15) as well as in 30 mg/kg/day males (6 of 15). The incidences of this change in both
dose groups were higher compared to the background incidence in controls (1 to 3 of
15). These foci were slightly more extensive in 150 mg/kg/day animals, and were
characterized by the intra-alveolar accumulation of macrophages having foamy, neutral­
lipid-rich cytoplasm.
Aspiration-induced bronchopneumonia occurred in three 150 mg/kg/day males (#'s 100,
102, 104), one 150 mg/kg/day female (#110), and one 30 mg/kg/day female (#78). The
pneumonia was characterized histologically by inflamed airways and associated alveoli
filled with mucous secretions and debris, usually accompanied by evidence of foreign
material.
Diffuse hepatocellular hypertrophy was noted in 150 mg/kg/day males (11 of 15) and
females (14 of 15). The hypertrophy was characterized by slight enlargement of
hepatocytes in all lobular zones, often resulting in compression of sinusoids. There was
no evidence of any other treatment-related microscopic hepatic changes.
Other microscopic changes in some drug-treated animals were considered to be stress­
related. Thymic atrophy occurred in 3 animals (#s 78, 102, 104) that died or were
sacrificed in moribund condition during the study. One 30 mg/kg/day female (#78) had
adrenal infarction with hemorrhage, which can be sporadically associated with severe
inflammation and stress (1 ). '
The slightly higher adrenal weights noted at 150 mg/kg/day in females were not
correlated with any microscopic tissue changes.
All remaining microscopic findings were minor gavage-related or common background
changes in laboratory rats seen at comparable incidences between control and drug-
treated animals.

There were no differences in group mean sperm count or percent motility between drug­
treated and control rats that were attributable to drug exposure.
Other effects:
effects observed, treatment-related
Description (incidence and severity):
HEPATIC MICROSOMAL ENZYME DETERMINATIONS
Treatment of rats with CJ-11,972-27 resulted in multiple changes in the hepatic
microsomal drug-metabolizing enzyme system. In males, there were significant
increases (1.47 - 2.7X control) in cytochrome P-450 content and all associated enzyme
activities at 150 mg/kg/day. In females, significant elevations in EROD, PROD and EMD
activities (1.85X, 6.0X and 6.9X control, respectively), indicative of CYP1A1, CYP281
and CYP3A, respectively; and cytochrome c reductase (2.34X control) were noted at
150 mg/kg/day. Slight elevations in PNOD. activity ( 1.47X control), indicative of CYP2E,
were noted at 150 mg/kg/day in males but not females.
Details on results:
The oral administration of CJ-11,972-27 to rats produced evidence of toxicity at 30 and
150 mg/kg/day.
Persistent raspy breathing was noted in the majority of animals at 30 and 150 mg/kg/day
throughout the study. This change was consistent with findings in previous rat
toxicology studies with CJ-11,972-27 and structurally-related compounds, and has been
associated with inflammation and stenosis of the upper respiratory tract. These upper
respiratory changes are likely related to topical irritant effects of the compound when
administered by gavage. This is supported by previous findings in acute toxicity studies
in rats with CJ-11,972-27 (Study No. 95-1044-13) and related compounds, in which
raspy breathing was noted after drug was administered by oral gavage but not when
given intravenously.
Treatment-related pulmonary lesions were also apparent which may be secondary to the
upper respiratory irritant effects. The raspy breathing at 30 and 150 mg/kg/day was
associated with a higher incidence of pulmonary foam cell foci in both dose groups
when compared to controls. Although these foci occur spontaneously at low incidence
especially in aging rats, they can increase in incidence and severity as a nonspecific
response to various pulmonary insults (2). Aspiration-induced bronchopneumonia was
also observed in several drug-treated animals, including one 30 mg/kg/day female (#78)
which died from gavage-related trauma and two 150 mg/kg/day animals (#'s 102 and
104) which died during the study. This change is possibly attributed to the inadvertent
deposition of compound or aspiration of biological fluids into the pulmonary tract during
or after dosing by gavage. This may have been facilitated by compound-related topical
respiratory tract irritation.
The death of four rats given 150 mg/kg/day during the study were therefore attributable
to topical or secondary respiratory effects of the compound. All of the animals showed
persistent raspy breathing prior to death. In three of the four animals, microscopic
respiratory tract lesions were evident. These changes consisted of either marked
tracheal inflammation (#101) or bronchopneumonia (#'s 102 and 104).
Body weight gains were also lower at 30 and 150 mg/kg/day which correlated with
decreased food consumption in males at the high dose. A few slight serum chemistry
changes (triglycerides, proteins) also noted at 150 mg/kg/day were considered effects
secondary to either decreased food consumption or poor hydration status (3). Slightly
higher neutrophil counts were also apparent at 30 and 150 mg/kg/day, consistent with
findings in previous rat toxicology studies with CJ-11,972-27 and related compounds.
These minimal changes may be related to the noted respiratory effects. Transient head
tremors were noted in one 150 mg/kg/day animal (#95) on days 24 and 25 of the study,
consistent with findings in a preliminary rat toleration study. No further episodes were
observed in this animal or any of the other high dose animals during the study. Tremors
have also been observed in dogs given CJ-11,972-27 at high doses.
Higher liver weights were observed at both 30 and 150 mg/kg/day, with hepatocellular
hypertrophy observed in the latter dose group. Increased liver weight coupled with
hepatocellular hypertrophy is generally associated with hepatic microsomal enzyme
induction and is considered an adaptive response of the liver to xenobiotic exposure (4).
In both sexes at the high dose, CJ-11,972-27 was consistently an inducer of hepatic
CYP1 A 1, CYP2B 1 and CYP3A on the basis of altered microsomal enzyme activities
associated with these specific cytochromes in the rat. Slight elevations in serum hepatic
marker enzymes and cholesterol were also apparent at 150 mg/kg/day, but these
changes did not correspond to any clinical or microscopic evidence of hepatic toxicity.
Minimal changes in serum hepatic enzymes may accompany the adaptive response of
the liver to microsomal enzyme inducers (5).
Slightly higher adrenal weights were apparent at 150 mg/kg/day in females, consistent
with gross evidence of adrenal enlargement noted in a preliminary rat toleration study at
this dose. In the present study, this subtle change was not associated with any clinical
or microscopic evidence of adrenal toxicity. The absence of any corroborative evidence
of adrenal toxicity in the present study precludes the assignment of these subtle adrenal
weight changes as clearly treatment-related.

Effect levels

Key result
Dose descriptor:
NOAEL
Effect level:
5 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
clinical signs
body weight and weight gain
organ weights and organ / body weight ratios
histopathology: non-neoplastic

Target system / organ toxicity

open allclose all
Critical effects observed:
yes
Lowest effective dose / conc.:
30 mg/kg bw/day (nominal)
System:
respiratory system: lower respiratory tract
Organ:
lungs
Treatment related:
yes
Dose response relationship:
yes
Relevant for humans:
yes
Critical effects observed:
yes
Lowest effective dose / conc.:
30 mg/kg bw/day (nominal)
System:
hepatobiliary
Organ:
liver
Treatment related:
yes
Dose response relationship:
yes
Relevant for humans:
yes

Applicant's summary and conclusion

Conclusions:
The oral administration of CJ-11,972-27 to rats produced persistent salivation, dose­
dependent decreased body weight gain, and upper respiratory (raspy breathing) and
secondary pulmonary tract changes at 30 and 150 mg/kg/day. The respiratory changes
were possibly initiated by topical irritant effects of the compound when administered by
oral gavage, and most likely contributed to four deaths at 150 mg/kg/day. Liver weights
were higher at 30 and 150 mg/kg/day, with hepatocellular hypertrophy and hepatic
microsomal enzyme induction noted at the high dose. No changes occurred at
5 mg/kg/day except for transient and minor occurrences of raspy breathing, possibly a
consequence of topical effects of the compound. Based upon these data, 5 mg/kg/day
was identified as a "no observed adverse effect level" (NOAEL) in this 93-day oral
toxicity study in rats with CJ-11,972-27.
Executive summary:

CJ-11,972-27,was administered by oral gavage to Sprague-Dawley rats (15/sex/dose) at doses of 5, 30 and 150 mg/kg/day for

93 consecutive days (3 months). A separate group of rats received 0.01 M citrate buffer

and served as vehicle controls. All animals were examined daily for clinical signs while

body weights and food consumption were recorded weekly. Ophthalmoscopic

examinations were performed, and hematology, chemistry and urinalysis parameters

measured. Serum drug concentrations were measured on days 1, 31 and 81. At the

conclusion of the dosing period, survivlng rats were necropsied and examined.

Selected organs were weighed and a comprehensive set of tissues was collected and

processed for microscopic examination. Liver samples were collected from some of the

rats (control and 150 mg/kg/day) to assess hepatic microsomal enzyme activities, and

seminal analysis was performed on all surviving male rats at necropsy.

Predominant and persistent clinical signs noted at both 30 and 150 mg/kg/day included

salivation and raspy breathing, with transient and minor incidents of these signs

observed in some 5 mg/kg/day animals. In addition to clinical signs of raspy breathing,

secondary microscopic pulmonary lesions were .noted at 30 and 150 mg/kg/day. These

consisted of a high incidence of pulmonary foam cell foci at 30 and 150 mg/kg/day, and

aspiration-induced bronchopneumonia noted in some animals primarily at

150 mg/kg/day. These changes were possibly initiated by topical irritant effects

produced by locally high concentrations of orally administered compound to the upper

respiratory tract, and most likely contributed to the deaths of four 150 mg/kg/day animals

during the study. Body weight gains were lower at 30 and 150 mg/kg/day which

correlated with decreased food consumption in males at the high dose. Changes in

clinical pathology parameters were generally limited to the 150 mg/kg/day dose group

and consisted of slightly elevated serum hepatic enzymes, alterations in serum lipids

and proteins and slightly higher neutrophil counts when compared to controls. Liver

weights were higher at 30 and 150 mg/kg/day, with hepatocellular hypertrophy and

induction of hepatic microsomal enzymes noted at the high dose. Adrenal weights were ·

slightly higher at 150 mg/kg/day in females but were not accompanied by clinical or

pathological evidence of adrenal toxicity. No treatment-related changes in sperm count

or motility were apparent. In general, serum exposure (as assessed by AUG) increased

in a supraproportional manner with increases in dose, and was generally higher in

females than in males. An increase in drug exposure over the course of treatment was

most apparent at 150 mg/kg/day, with:no difference in exposure noted between days 31

and 81.

Based upon these data, 5 mg/kg/day was identified as a "no observed adverse effect

level" (NOAEL) in this 93-day oral toxicity study in rats with CJ-11,972-27.