[No public or meaningful name is available]

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 June 2017 - 20 July 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

22 January 2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of (1-methylethylidene)bis(4,1-phenyleneoxy-2,1-ethanediyl) bismethacrylate and 2-{4-[2-(4-{2-[2-(methacryloyloxy)ethoxy]ethoxy}phenyl)propan-2-yl]phenoxy}ethyl methacrylate

EC Number:

939-702-5

Molecular formula:

C23H24O4 (C2H4O)n

IUPAC Name:

Reaction mass of (1-methylethylidene)bis(4,1-phenyleneoxy-2,1-ethanediyl) bismethacrylate and 2-{4-[2-(4-{2-[2-(methacryloyloxy)ethoxy]ethoxy}phenyl)propan-2-yl]phenoxy}ethyl methacrylate

Test material form:

liquid

Test animals

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: breeder: Janvier, le Genest-Saint-Isle, France
- Age: at the beginning of the treatment period, the animals were 10-11 weeks old
- Mean body weight: at the beginning of the treatment period, the animals had a mean body weight of 300 g (range: 255 g to 360 g)
- Fasting period before study: no
- Housing: the animals were individually housed in polycarbonate cages (Tecniplast 2154, 940 cm2)
- Diet: SSNIFF R/M-H pelleted diet (free access)
- Water: tap water filtered with a 0.22 µm filter (free access)
- Acclimation period: for a period of 4 or 5 days before the beginning of the treatment period.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2°C
- Humidity (%): 50 ± 20%
- Air changes (per hr): aboutr 8 to 15 cycles/hour of filtered, non-recycled air
- Photoperiod (hrs dark / hrs light): 12 h/12 h.

IN-LIFE DATES: 26 June 2017 to 20 July 2017.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Details on exposure:

PREPARATION OF DOSING FORMULATIONS:
- Emulsion in the vehicle
- Concentration in vehicle: 20, 60 and 200 mg/mL
- Amount of vehicle (if gavage): 5 mL/kg/day

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Type of method: High Performance Liquid Chromatography with UV detection (HPLC/UV)
Test item concentrations: remained within an acceptable range of variations (-1.8% to +8.6%) when compared to the nominal values (± 15% of the nominal concentrations)
Homogeneity: the dose formulations containing the test item and prepared at 2 mg/mL and 200 mg/mL in PEG 400 were found to be homogeneous after preparation. Dose formulations ranging from 2 mg/mL to 200 mg/mL are therefore considered to be suitable for routine administration in GLP Toxicological studies, and have to be maintained under magnetic agitation after preparation and during the administration procedure to animals in follow-up studies.
Stability: not assessed, dose formulation prepared daily

Details on mating procedure:

The females were mated at the breeder's facility. The day of confirmed mating (detection of a vaginal plug) was designated as Day 0 p.c.

Duration of treatment / exposure:

The dose formulations were administered daily from Day 6 to Day 20 p.c. inclusive.

Frequency of treatment:

Daily

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

100 mg/kg bw/day (actual dose received)

Doses / concentrations 2

Dose / conc.:

300 mg/kg bw/day (actual dose received)

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

24 females

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
The dose levels were selected in agreement with the Sponsor, based on the results of a previous OECD 422 study performed in Wistar Han rats.
In the previous study, rats received the test item daily by gavage at dose levels of 62, 250 or 1000 mg/kg/day for 29 days (males) or 43 to 46 days (females).
There were no toxicologically relevant changes in any of the parental parameters (i.e. clinical signs, Functional Observation Battery, motor activity, body weight, body weight change, food consumption, clinical laboratory investigations and histopathology examination). Mating, fertility and conception indices, pre-coital time, numbers of corpora lutea and implantation sites, gestation index, duration of gestation, and pup body weights were unaffected by the treatment and no developmental toxicity was observed up to the dose level of 1000 mg/kg/day.
Based on these available data, the dose levels selected for the present study were 100, 300 and 1000 mg/kg/day.

- Rationale for animal assignment: computerized stratification procedure.

Examinations

Maternal examinations:

MORTALITY/MORBIDITY:
- Time schedule: each animal was checked for mortality and morbidity once a day before the treatment period and at least twice a day during the treatment period, including weekends and public holidays.

CLINICAL SIGNS:
- Time schedule: from arrival, each animal was observed once a day as part of the routine examinations. From the start of the treatment period, each animal was observed once a day, at approximately the same time, for the recording of clinical signs.

BODY WEIGHT:
- Time schedule: the body weight of each female was recorded on Days 2, 4, 6, 9, 12, 15, 18 and 21 p.c.

FOOD CONSUMPTION:
- Time schedule: the quantity of food consumed by each female was recorded for the following intervals: Days 2-4, 4-6, 6-9, 9-12, 12-15, 15-18 and 18-21 p.c.

POST-MORTEM MACROSCOPIC EXAMINATION:
- Sacrifice on Day 21 post-coitum.
- Examined: principal thoracic and abdominal organs.

Ovaries and uterine content:

The ovaries and uterus of the females were examined to determine:
- gravid uterus weight,
- number of corpora lutea,
- number and distribution of dead and live fetuses,
- number and distribution of early and late resorptions,
- number and distribution of uterine scars,
- number and distribution of implantation sites,
- gross evaluation of placentas.

Fetal examinations:

- External examinations: Yes: all fetuses per litter
- Soft tissue examinations: Yes: half fetuses per litter
- Skeletal examinations: Yes: half fetuses per litter
- Head examinations: Yes: half fetuses per litter
- Other: number dead and live, body weight, sex.

Statistics:

Data were compared by one-way analysis of variance and Dunnett test (mean values being considered as normally distributed and variances being considered as homogeneous) or by the Fisher exact probability test (proportions).

Indices:

% Pre-implantation loss = 100 * (Number of corpora lutea - Number of implantation sites) / Number of corpora lutea
% Post-implantation loss = 100 * (Number of implantation sites - Number of live fetuses) / Number of implantation sites

Historical control data:

Cf attached document

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

See table 1.
Test item-related clinical signs consisted of ptyalism, which was observed for 1 to 11 days in many females given 100 mg/kg/day and in most females given 300 or 1000 mg/kg/day. These clinical signs were considered as non-adverse.
Emaciated appearance (without body weight loss), associated with piloerection, was noted in 1/24 females given 100 mg/kg/day from Day 20 p.c. These findings were considered to be unrelated to the test item treatment, as they were not dose-related and were reported in only one animal.

Mortality:

no mortality observed

Description (incidence):

There were no unscheduled deaths.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

See table 2.
There were no effects on mean body weight or mean body weight change.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

See table 3.
There were no effects of treatment with the test item.

Food efficiency:

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Endocrine findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

See table 4.
There were no test item-related macroscopic findings.
The macroscopic observations were not attributed to the test item treatment as they were reported with only isolated incidences, were not dose-related and/or are findings commonly observed in rats of this strain and age.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Other effects:

effects observed, non-treatment-related

Description (incidence and severity):

See table 5.
There were no test item-related effects on mean gravid uterus weight, mean carcass weight or net body weight change.
At 1000 mg/kg/day females had a low mean net body weight change when compared with controls (-15%). This was mainly due to the high value recorded in one control female (one female: +117 g). This difference, which was not statistically significant and which did not correlate with any other findings, was therefore considered not to be test item-related.

Maternal developmental toxicity

Number of abortions:

no effects observed

Pre- and post-implantation loss:

no effects observed

Description (incidence and severity):

See table 6.
There were no test item-related effects.

Total litter losses by resorption:

no effects observed

Description (incidence and severity):

See table 6.
There were no test item-related effects.

Early or late resorptions:

no effects observed

Description (incidence and severity):

See table 6.
There were no test item-related effects.

Dead fetuses:

no effects observed

Description (incidence and severity):

See table 6.
No dead fetuses.

Changes in pregnancy duration:

not examined

Changes in number of pregnant:

effects observed, non-treatment-related

Description (incidence and severity):

See table 6.
There were no test item-related effects.

Other effects:

not specified

Effect levels (maternal animals)

Key result

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Remarks on result:

not determinable due to absence of adverse toxic effects

Maternal abnormalities

Abnormalities:

no effects observed

Results (fetuses)

Fetal body weight changes:

no effects observed

Description (incidence and severity):

See table 7.
There were no effects on mean fetal body weight

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Description (incidence and severity):

See table 7.
There were no effects on sex ratio (percentage of male fetuses).

Changes in litter size and weights:

no effects observed

Anogenital distance of all rodent fetuses:

not examined

External malformations:

effects observed, non-treatment-related

Description (incidence and severity):

See table 8 (variations)
There were no external variations in the test item-treated groups.
In the control group, one fetus had protruding tongue; this finding was within the range of the historical control data.


See table 9 (malformations)
There was no test item-related increase in the frequency of external malformations.
In the 1000 mg/kg/day group, there was one malformed fetus (with anasarca). As anasarca was observed with a similar litter incidence in the control group, it was considered to be unrelated to the test item treatment.
In the 100 and 300 mg/kg/day groups, one litter per dose level had a malformed fetus (2 litters with omphalocele, respectively). As this malformation was observed without a dose-relationship and was within the range of the historical control data, it was considered to be unrelated to the test item treatment.
In the control group, one fetus had anasarca and omphalocele; these findings are commonly observed in this species and strain (Morita et al., 1987).

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

See table 10 (cartilage)
There were no relevant differences from controls in the frequency of cartilage observations.
In the 1000 mg/kg/day group and when compared with controls, there was a slight increase in presence of sternebra(e) cartilage. As the fetal and litter incidences were of low magnitude and within or very close to the range of the historical control data, these effects were considered to be of no toxicologically importance (see § Variations).
The other findings were observed in control and treated groups, without a dose relationship and/or with an isolated incidence and/or with an incidence similar to the historical control data. Therefore they were considered to be unrelated to the test item treatment.

See table 11 (variations)
There were no relevant differences from controls in the frequency of skeletal variations.
In the 1000 mg/kg/day group and when compared with controls, there was a slight increase in skeletal variations (i.e. incomplete ossification of 6th sternebra and/or extra external ossification site). As the fetal and litter incidences were of low magnitude and within or very close to the range of the historical control data, these test item-related effects were considered to be of no toxicologically importance in absence of test item-related effects on mean fetal body weight.
The other variations [i.e. incomplete ossification of interparietal, incomplete ossification of thoracic vertebra(e) centrum and incomplete ossification of caudal vertebra(e) arch] were observed in control and/or treated groups, without a dose relationship and/or with an isolated incidence and/or with an incidence similar to the historical control data. Therefore they were considered to be unrelated to the test item treatment although the incidences were sometimes statistically significant.

See table 12 (malformations)
There was no test item-related increase in the frequency of skeletal malformations.
In the 1000 mg/kg/day group, one litter had a malformed fetus (with split interparietal) and one other litter had two malformed fetuses (with less than 15 caudal vertebrae). As these malformations were of isolated occurrence and/or as fetal and litter incidences were within or close to the historical control data, a test item-related effect was considered to be unlikely.
In the 300 mg/kg/day group, one litter had a malformed fetus (with split interparietal). As the malformation was of isolated occurrence, a test item-related effect was considered to be unlikely.
In the 100 mg/kg/day group, one litter had a malformed fetus (with fused ribs). As this malformation was observed without a dose-relationship and was within the range of the historical control data, it was considered to be unrelated to the test item treatment.
In the control group, two litters had one malformed fetus (one with an extra sternebra, and one with absent digits).

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

See table 13 (variations)
There was no test item-related increase of the frequency of soft tissue variations.
Tissue variations (i.e. irregular color of the liver, colored focus on the liver, short or absent innominate artery, dilated renal pelvis, dilated ureter, fluid-filled abdomen and/or fluid-filled thoracic cavity) were observed in control and/or treated groups, without a dose-relationship, with an isolated incidence and/or with an incidence similar to the historical control data. Therefore they were considered to be unrelated to the test item treatment.

See table 14 (malformations)
There was no test item-related increase in the frequency of soft tissue malformations.
In the 1000 mg/kg/day group, one litter had a malformed fetus with absence of the left kidney and the left ureter.
In the 300 mg/kg/day group, one litter had a malformed fetus with marked dilated renal pelvis and marked dilated ureter on the right side.
In the 100 mg/kg/day group, one litter had a malformed fetus with marked dilated renal pelvis and marked dilated ureter on the right side.
In the control group, one litter had a malformed fetus with marked dilated renal pelvis.
These tissue malformations were observed in control and treated groups, without a dose relationship, with an isolated incidence and/or with an incidence similar to the historical control data. Therefore they were considered to be unrelated to the test item treatment.

Other effects:

not specified

Effect levels (fetuses)

Key result

Dose descriptor:

NOEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Fetal abnormalities

Abnormalities:

no effects observed

Overall developmental toxicity

Developmental effects observed:

no

Any other information on results incl. tables

Table 1: Clinical signs

 

Dose level (mg/kg/day)	0	100	300	1000
Ptyalism		13	22	21
Piloerection		1
Emaciated appearance		1
Number of affected animals	0/24	14/24	22/24	21/24

 

Table 2: Body weight

 

Dose level (mg/kg/day)	0	100	300	1000
Body weight (g)
Day 6p.c.	302	300	300	299
	-	(-1)	(-1)	(-1)
Day 9p.c.	317	314	315	313
	-	(-1)	(-1)	(-1)
Day 12p.c.	338	335	334	332
	-	(-1)	(-1)	(-2)
Day 15p.c.	354	352	352	351
	-	(-1)	(-1)	(-1)
Day 18p.c.	401	396	395	396
	-	(-1)	(-1)	(-1)
Day 21p.c.	455	449	447	451
	-	(-1)	(-2)	(-1)
Body weight change (g)
Days 6 - 9p.c.	+15	+14	+15	+14
Days 9 - 12p.c.	+21	+21	+19	+19
Days 12 - 15p.c.	+17	+18	+18	+18
Days 15- 18p.c.	+46	+44	+43	+46
Days 18 - 21p.c.	+55	+53	+51	+54
Days 6 - 21p.c.	+153	+149	+147	+152
	-	(-3)	(-4)	(-1)

p.c.: post-coitum.

-: not applicable.

( ): in brackets, percentage differencevs.controls.

Table 3: Food consumption

 

Dose level (mg/kg/day)	0	100	300	1000
. Days 6 - 9p.c.	24	25	25	26
. Days 9 - 12p.c.	27	28	28	29
. Days 12 - 15p.c.	29	29	29	30
. Days 15 - 18p.c.	33	33	33	33
. Days 18 - 21p.c.	34	33	33	34

p.c.:post-coitum

Table 4: Maternal necropsy findings

 

Dose level (mg/kg/day)	0	100	300	1000
Kidney: dilated pelvis, unilateral		1
Kidney, ureter and uterine horn, unilateral absence			1
Ovary: serous cyst(s), unilateral				1
Placenta: enlarged				1 (1 fetus)
Number of affected animals	0/24	1/24	1/24	2/24

 

Table 5: Net body weight change

 

Dose level (mg/kg/day)	0	100	300	1000
Gravid uterus weight	99	99 (0)	98 (-1)	105 (+6)
Carcass weight	356	350 (-2)	349 (-2)	345 (-3)
Net body weight change from Day 6p.c.	+54	+50	+49	+46

( ): in brackets, percentage differencevs.controls.

p.c.:post-coitum.

^(a): weights are rounded values.

Table 6: Hysterectomy data

 

Dose level (mg/kg/day)	0	100	300	1000
Number of pregnant females at hysterectomy	24	23	23	24
Number of females with live fetuses at termination	24	23	23	24
Number of females with total resorption	0	0	0	0
Mean number ofcorpora lutea	15.1	14.7	14.5	15.1
Mean number of implantation sites	13.9	13.4	12.9	14.0
Mean pre-implantation loss (%)	8.5	7.8	10.8	7.3
Mean number of live fetuses	12.4	12.3	12.0	12.8
Dead fetuses (%)	0.0	0.0	0.0	0.0
Mean number of implantation scars	0.0	0.0	0.0	0.0
Mean number of early resorptions	1.3	1.0	0.8	1.1
Mean number of late resorptions	0.2	0.2	0.2	0.2
Mean post-implantation loss (%)	11.4	8.5	7.9	9.0

Table 7: Fetal body weight and sex ratio

 

Dose-level (mg/kg/day)	0	100	300	1000
Mean fetal body weight (g)	5.85 -	5.78 (-1)	5.89 (+1)	5.93(+1)
Mean fetal body weight of males (g)	6.00 -	5.90 (-2)	6.04 (+1)	6.12(+2)
Mean fetal body weight of females (g)	5.65 -	5.66 (0)	5.75 (+2)	5.78(+2)
Mean percentage of male fetuses (%)	49.8	48.4	50.2	49.0

( ): in brackets, percentage differencevs.controls.

-: not applicable.

Table 8: Fetal external variations

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	388
Number of live fetuses	297	283	275	306	5000
Litters affected, n (%)	1 (4.2)	0 (0)	0 (0)	0 (0)	6 (1.5)^(b)
Fetuses affected, n (%)	1 (0.3)	0 (0)	0 (0)	0 (0)	7 (0.1)^(b)
Protruding tongue, F (L)	0.3 (4.2)	0 (0)	0 (0)	0 (0)	0.4 (4.8)^(a)

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

^(a): maximum incidence.

^(b): mean incidence.

Table 9: Fetal external malformations

 

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	388
Number of live fetuses	297	283	275	306	5000
Litters affected, n (%)	1 (4.2)	1 (4.3)	1 (4.3)	1 (4.2)	11 (2.8)^(b)
Fetuses affected, n (%)	1 (0.3)	1 (0.4)	1 (0.4)	1 (0.3)	13 (0.3)^(b)
Anasarca, F (L) (%)	0.3 (4.2)	0 (0)	0 (0)	0.3 (4.2)	0 (0.0)^(b)
Omphalocele, F (L) (%)	0.3 (4.2)	0.4 (4.3)	0.4 (4.3)	0 (0)	0.4 (5.3)^(a)

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

^(a): maximum incidence.

^(b): mean incidence.

Table 10: Fetal skeletal examinations (cartilage)

 

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	388
Number of live fetuses	156	147	140	160	2596
Litters affected, n (%)	24 (100.0)	23 (100.0)	22 (95.7)	23 (95.8)	236 (60.8)^(b)
Fetuses affected, n (%)	109 (69.9)	97 (66.0)	82 (58.6)	101 (63.1)	990 (38.1)^(b)
Cartilage of sternebra(e) present, F(L)	1.9 (12.5)	1.4 (8.7)	0 (0)	5.0 (16.7)	3.8 (21.7)^(a)

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

^(a): maximum incidence.

^(b): mean incidence.

Table 11: Fetal skeletal variations

 

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	388
Number of live fetuses	156	147	140	160	2596
Litters affected, n (%)	24 (100.0)	23 (100.0)	22 (95.7)	23 (95.8)	345 (88.9)^(b)
Fetuses affected, n (%)	112 (71.8)	99 (67.3)	85 (60.7)	104 (65.0)	1267 (48.8)^(b)
6^thsternebra: incomplete ossification, F(L)	0.6 (4.2)	0.7 (4.3)	0 (0)	4.4(16.7)	2.9 (16.7)^(a)
Extra sternebral ossification site, F(L)	3.2 (16.7)	1.4 (8.7)	2.1 (13.0)	3.1 (20.8)	1.7 (10.0)^(a)
Interparietal: incomplete ossification, F(L)	4.5 (20.8)	3.4 (13.0)	1.4 (4.3)	5.6 (16.7)	9.2 (45.0)^(a)
Thoracic vertebra(e): incomplete ossification of centrum, F(L)	0 (0)	3.4* (17.4)*	2.1 (8.7)	1.9 (12.5)	29.6 (87.5)^(a)
Caudal vertebra(e): incomplete ossification of arch, F(L)	0 (0)	0 (0)	0.7 (4.3)	1.3 (4.2)	2.3 (15.0)^(a)

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

^(a): maximum incidence.

^(b): mean incidence.

Statistically significant for number of litters and fetuses: *: p < 0.05

Table 12: Fetal skeletal malformations

 

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	388
Number of live fetuses	156	147	140	160	2596
Litters affected, n (%)	2 (8.3)	1 (4.3)	1 (4.3)	2 (8.3)	15 (3.9)^(b)
Fetuses affected, n (%)	2 (1.3)	1 (0.7)	1 (0.7)	3 (1.9)	18 (0.7)^(b)
Interparietal: split, F(L)	0 (0)	0 (0)	0.7 (4.3)	0.6 (4.2)	0 (0.0)
Caudal vertebra(e): less than 15 caudal vertebrae, F(L)	0 (0)	0 (0)	0(0)	1.3 (4.2)	0.6 (4.0)^(a)
Extra sternebra, F(L)	0.6 (4.2)	0 (0)	0 (0)	0 (0)	0 (0.0)
Fused ribs F(L)	0 (0)	0.7 (4.3)	0 (0)	0 (0)	0.8 (5.6)^(a)
Hindpaw : absent digit(s), F (L)	0.6 (4.2)	0 (0)	0 (0)	0 (0)	/

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

/: not reported in HCD.

^(a): maximum incidence.

^(b): mean incidence.

Table 13: Fetal soft tissue variations

 

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	387
Number of live fetuses	141	136	135	146	2404
Litters affected, n (%)	6 (25.0)	6 (26.1)	5 (21.7)	3 (12.5)	86 (22.2)^(b)
Fetuses affected, n (%)	9 (6.4)	10 (7.4)	9 (6.7)	4 (2.7)	119 (5.0)^(b)
Liver: irregular color, F(L)	0 (0)	0.7 (4.3)	0 (0)	0 (0)	/
Liver: colored focus, F(L)	0 (0)	1.5 (8.7)	0 (0)	0 (0)	0.8 (5.0)^(a)
Short innominate artery, F (L)	0 (0)	0.7 (4.3)	0 (0)	0.7 (4.2)	3.7 (22.7)^(a)
Absent innominate artery, F (L)	0 (0)	0 (0)	0.7 (4.3)	0 (0)	5.1 (25.0)^(a)
Dilated renal pelvis, F (L)	3.5 (12.5)	2.9 (8.7)	3.7 (13.0)	0.7 (4.2)	9.5 (28.6)^(a)
Dilated ureter, F (L)	6.4 (25.0)	4.4 (13.0)	5.2 (21.7)	1.4 (4.2)	7.1 (28.0)^(a)
Fluid-filled abdomen, F (L)	0 (0)	0 (0)	0 (0)	0.7 (4.2)	0.9 (5.0)^(a)
Fluid-filled thoracic cavity, F(L)	0 (0)	0 (0)	0 (0)	0.7 (4.2)	/

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

/: not reported in HCD.

^(a): maximum incidence.

^(b): mean incidence.

Table 14: Fetal soft tissue malformations

 

Dose level (mg/kg/day)	0	100	300	1000	HCD
Dams with live fetuses	24	23	23	24	387
Number of live fetuses	141	136	135	146	2404
Litters affected, n (%)	1 (4.2)	1 (4.3)	1 (4.3)	1 (4.2)	7 (1.8)^(b)
Fetuses affected, n (%)	1 (0.7)	1 (0.7)	1 (0.7)	1 (0.7)	13 (0.5)^(b)
Marked dilated renal pelvis, F(L)	0.7 (4.2)	0.7 (4.3)	0.7 (4.3)	0 (0)	2.4 (4.8)^(a)
Marked dilated ureter, F(L)	0 (0)	0.7 (4.3)	0.7 (4.3)	0 (0)	4.8 (4.8)^(a)
Absent kidney, F (L)	0 (0)	0 (0)	0 (0)	0.7 (4.2)	0.7 (4.5)^(a)
Absent ureter, F(L)	0 (0)	0 (0)	0 (0)	0.7 (4.2)	0 (0.0)

F: fetal incidence.

L: litter incidence.

HCD: Historical Control Data (control data collected from 18 studies covering a period ranging from March 2014 to July 2016).

^(a): maximum incidence.

^(b): mean incidence.

Applicant's summary and conclusion

Conclusions:

The test item was administered to pregnant Sprague-Dawley rats by gavage, once daily, from Day 6 to Day 20 p.c., inclusive, at the dose levels of 100, 300 and 1000 mg/kg/day. The control group received the vehicle, PEG 400, under the same experimental conditions.

On the basis of the results obtained in this study:
- the No Observed Adverse Effect Level (NOAEL) for maternal parameters was considered to be 1000 mg/kg/day based on ptyalism,
- the No Observed Effect Level (NOEL) for embryo-fetal development was considered to be 1000 mg/kg/day.

Executive summary:

The objective of this study was to evaluate the potential toxic effects of the test item on the pregnant female and on embryonic and fetal development, following daily oral administration (gavage) to pregnant female rats from implantation until the day before scheduled hysterectomy [Day 6 to Day 20 post-coitum (p.c.) inclusive].

This GLP study was carried out according to OECD test guideline No. 414 (22 January 2001).

 

Methods

Three groups of 24 time-mated female Sprague-Dawley rats received the test item by the oral route (gavage), at a dose level of 100, 300 or 1000 mg/kg/day, once daily from Day 6 to Day 20 p.c. inclusive. Another group of 24 time-mated female rats received the vehicle only, PEG 400, under the same experimental conditions and acted as a control group. A constant dosage volume of 5 mL/kg/day was used. The test item concentrations in the dose formulations were determined. The animals were checked daily for mortality and clinical signs. Body weight and food consumption were recorded at designated intervals. On Day 21 p.c., the females were euthanized and a macroscopic post-mortem examination was performed. Hysterectomy was performed and the numbers of corpora lutea, implantation sites, uterine scars, early and late resorptions, and live and dead fetuses were recorded. The fetuses were weighed, sexed and examined for external, soft tissue and skeletal abnormalities (including cartilage). Macroscopic lesions were collected from all dams and preserved in 10% buffered formalin.

 

Results

Chemical analyses

The concentrations of the test item in the dose formulations performed on Weeks 1 and 3 (-1.8% to +8.6% of the nominal concentrations) remained within an acceptable range of variations (± 15% of the nominal concentrations).

No test item was observed in the control dose formulation.

 

Pregnancy status

All females were pregnant with the exception of two (one in the 100 and one in the 300 mg/kg/day groups).

 

Mortality

There were no unscheduled deaths.

 

Clinical signs

Ptyalism was noted in 13/24 females given 100 mg/kg/day, 22/24 females given 300 mg/kg/day and 21/24 females given 1000 mg/kg/day. This finding was considered to be test item-related but not adverse.

 

Body weight, body weight change and food consumption

There were no effects.

 

Macroscopic post-mortem examination

No test item-related findings were observed.

 

Net body weight change and hysterectomy data

No test item-related changes were observed in the gravid uterus weight, carcass weight, net body weight change or hysterectomy data.

 

Fetal body weight and sex-ratio

There were no effects on fetal body weight or sex-ratio.

 

Fetal examinations

External examination:

. there were no test item-related variations or malformations at external examination.

 

Soft tissue examination:

. there were no test item-related variations or malformations at soft tissue examination.

 

Cartilage and skeletal examinations:

. there were no relevant differences from controls in the frequency of skeletal variations and no test item-related malformations at skeletal examination.

 

Conclusion

The test item was administered to pregnant Sprague-Dawley rats by gavage, once daily, from Day 6 to Day 20 p.c., inclusive, at the dose levels of 100, 300 and 1000 mg/kg/day. The control group received the vehicle, PEG 400, under the same experimental conditions.

 

On the basis of the results obtained in this study:

. the No Observed Adverse Effect Level (NOAEL) for maternal parameters was considered to be 1000 mg/kg/day based on ptyalism,

. the No Observed Effect Level (NOEL) for embryo-fetal development was considered to be 1000 mg/kg/day.