Dihydrogen hexahydroxyplatinate

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 September 2014 - 30 June 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, conducted according to GLP.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 422 (Combined repeated dose and reproduction / developmental screening)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dihydrogen hexahydroxyplatinate

EC Number:

257-471-2

EC Name:

Dihydrogen hexahydroxyplatinate

Cas Number:

51850-20-5

Molecular formula:

H6O6Pt.2H

IUPAC Name:

hexahydroxyplatinate(2-)

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): dihydrogen hexahydroxyplatinate.
- Substance type: powder.
- Physical state: solid.
- Analytical purity: no data.
- Impurities (identity and concentrations): no data.
- Composition of test material, percentage of components: 64.83% platinum w/w.
- Isomers composition: not applicable.
- Purity test date: 28 May 2013.
- Lot/batch No.: CZ0185.
- Expiration date of the lot/batch: June 2018.
- Stability under test conditions: 5 years.
- Storage condition of test material: At +10 to +25 deg C, in a tightly closed container, protected from direct sunlight.

Test animals

Species:

rat

Strain:

Crj: CD(SD)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, 97633 Sulzfeld, Germany.
- Age at study initiation: 67 days (at first test item administration).
- Weight at study initiation: males: 326.4 - 402.7 g; females: 189.4 - 246.0 g (at first test item administration).
- Fasting period before study: no data.
- Housing: animals were housed singly, except during the mating period.
- Diet (e.g. ad libitum): certified commercial diet, offered ad libitum.
- Water (e.g. ad libitum): tap water, offered ad libitum.
- Acclimation period: 8 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): room temperature of 22degC +/- 3degC (maximum range).
- Humidity (%): relative humidity of 55% +/- 15% (maximum range).
- Air changes (per hr): no data.
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light, about 150 lux.

IN-LIFE DATES:
From: July 2014.
To: 23 October 2014 (males); 14 November 2014 (females).

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: test item formulations were prepared once weekly and stored in a tightly closed container at room temperature (+10 to +25 degC) until use.

DIET PREPARATION
- Rate of preparation of diet (frequency): not applicable.
- Mixing appropriate amounts with (Type of food): not applicable.
- Storage temperature of food: not applicable.

VEHICLE
- Justification for use and choice of vehicle (if other than water): the test substance was found to be unstable in water and other aqueous vehicles. Stability for 7 days in corn oil was demonstrated in an identity and stability investigation, and thus corn oil was taken forward as the vehicle for this study.
- Concentration in vehicle: 20, 60 or 200 mg test item/mL vehicle.
- Amount of vehicle (if gavage): 5 mL/kg bw/day.
- Lot/batch no. (if required): Batch nos. 13249003 and 13249006, Caesar & Loretz GmbH, 40721 Hilden, Germany.
- Purity: no data.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Samples of approximately 10 mL were collected once weekly, at the time of preparation of the formulation, and analysed for homogeneity and concentration.

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: until pregnancy occurred, or two weeks.
- Proof of pregnancy: presence of sperm or a vaginal plug referred to as the day of conception (day 0 of pregnancy).
- After successful mating each pregnant female was caged (how): except during mating, animals were housed singly.

Duration of treatment / exposure:

Males were dosed from test days 1-35 (inclusive), including 2 weeks prior to mating, the mating period and approximately 2 weeks post-mating. Females were dosed from test day 1 (2 weeks prior to mating), throughout mating and gestation, until day 3 post-partum or the day before sacrifice (from test day 41 for the first sacrificed females to test day 58 for the last sacrificed female).

Frequency of treatment:

Once daily.

Duration of test:

Final treatment was administered on test day 58.

No. of animals per sex per dose:

12.

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: dose levels were selected based a 14-day dose range finding study conducted at the same testing laboratory. In the dose range finding study, male and female rats were treated with 1000 mg test item/kg bw/day. No animal died prematurely, there were no test item-related adverse effects, and no test item-related changes noted at necropsy.
- Rationale for animal assignment (if not random): computer-generated randomisation programme.
- Rationale for selecting satellite groups: not applicable.
- Post-exposure recovery period in satellite groups: not applicable.
- Section schedule rationale (if not random): not applicable.

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: before and after dosing and, additionally, regularly throughout the working day (7:00 to 15:45 on Monday to Friday; 7:00 to 11:00 with a final check at 15:00 on Saturday and Sunday).
- Cage side observations included any behavioural changes, signs of illness or reaction to treatment. Skin/fur, eyes, mucous membranes, respiratory and circulatory systems, somatomotor activity and behaviour patterns were recorded, together with the onset, intensity and duration of any signs observed.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once weekly, once before the first administration and once a week thereafter.
- Signs recorded included: changes in skin, fur, eyes, mucous membranes; occurrence of secretions, excretions and autonomic activity; changes in gait, posture and response to handling; behavioural changes.

BODY WEIGHT: Yes
- Time schedule for examinations: males and females were weighed on the first day of dosing, weekly thereafter, and at termination. During gestations, females were weighed on days 0, 7, 14 and 20, within 24 hours of parturition (day 1 post-partum), and day 4 post-partum.

FOOD AND WATER CONSUMPTION:
- Food consumption for each animal determined: Yes.
- Food intake per animal was determined using the total amount of food given to and left by each animal.
- Drinking water consumption for each animal determined: Yes, by daily visual appraisal throughout the study.

SACRIFCE
Dams with offspring were sacrificed on day 4 post-partum.

GROSS NECROPSY
- Adult animals were examined macroscopically at sacrifice for any abnormalities or pathological changes, with particular attention given to the reproductive organs.
- The number of implantation sites and corpora lutea were recorded.

HISTOPATHOLOGY / ORGAN WEIGHTS
- The mammary glands, ovaries, uterus (including cervix and oviducts), vagina and all organs showing macroscopic lesions of all adult animals were preserved. The weights of the ovaries and uterus (including cervix and oviducts) were recorded before fixation.

Ovaries and uterine content:

The ovaries and uterine content were examined after termination: Ovaries were examined histopathologically; uterine content not examined as dams only sacrificed post-partum.
Examinations included:
- Gravid uterus weight: No
- Number of corpora lutea: Yes
- Number of implantation sites: Yes
- Number of early/late resorptions: No data; pre- and post-implantation loss were calculated from the number of corpora lutea, implantations and living foetuses.

Fetal examinations:

- External examinations: Yes: [all per litter]
- Soft tissue examinations: No data
- Skeletal examinations: No data
- Head examinations: No data

Statistics:

Analysis of normal distribution and homogeneity of variances was performed using the Shapiro-Wilks test and the Bartlett test.
One-way analysis of variance was performed using Anova or the Kruskal-Wallis test.
Intergroup comparisons, in the case of significant differences, were made using the Dunnett test.
Statistical analyses of non-parametrical data were performed using Fisher's exact test or the Chi-squared test.

Indices:

Birth Index [%] = (Total number of pups born (alive + dead)/Number of implantation scars) x 100
Live Birth Index [%] = (Number of pups alive on day 0/1 of lactation/Total number of pups (alive + dead)) x 100
Survival Index [%] = (Number of pups alive on day 4/Number of pups alive on day 0/1) x 100
Pre-implantation loss [%] = ((corpora lutea – implantations)/corpora lutea) x 100
Post-implantation loss [%] = ((implantations - living neonates)/implantations) x 100

Historical control data:

No data.

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
There was no test item-related increase in mortality, no clinical signs of toxicity, changes in body weight or food consumption, or altered haematological, clinical chemistry or neurobehavioural parameters. Treatment also had no effect on the measured reproductive or fertility parameters.

Effect levels (maternal animals)

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: No developmental toxicity seen at the highest tested dose

Results (fetuses)

Fetal body weight changes:

no effects observed

Description (incidence and severity):

No differences were noted between the control and the treatment groups for the mean body weight of the pups and the mean total litter weight of the dams.
Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): not examined

Reduction in number of live offspring:

not examined

Changes in sex ratio:

not examined

Changes in litter size and weights:

not examined

Changes in postnatal survival:

not examined

External malformations:

no effects observed

Description (incidence and severity):

The external macroscopic examination after sacrifice revealed no test item-related gross abnormalities.

Skeletal malformations:

not examined

Visceral malformations:

not examined

Other effects:

not specified

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
No gross abnormalities were observed during macroscopic external examination of control pups or those from treated dams.

Effect levels (fetuses)

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No embryotoxicity/teratogenicity effects seen at the highest tested dose

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

In an OECD Test Guideline 422 combined repeated dose and reproductive/developmental toxicity screening study in rats, involving the gavage administration of dihydrogen hexahydroxyplatinate for at least 35 days (including, for females, throughout mating, gestation and up to post-natal day 3), no signs of developmental toxicity or any adverse effects on pups were observed. The study NOAEL for developmental toxicity/embryotoxicity was the highest tested dose (1000 mg/kg bw/day).

Executive summary:

In a combined repeated dose toxicity and reproductive/developmental toxicity screening study, conducted according to OECD Test Guideline 422 and to GLP, CD rats (12/sex/group) were orally administered dihydrogen hexahydroxyplatinate by stomach tube (gavage) at doses of 0, 100, 300 or 1000 mg/kg bw/day. Males were dosed for 35 days (2 weeks pre-mating, during the mating period and for approximately 2 weeks post-mating). Females were dosed for 14 days pre-mating, through mating, gestation and up to post-partum day 3 (test day 41-58).

 

There were no reported clinical signs of toxicity in the dams, and no gross pathological changes to the pups that were attributed to treatment. The study NOAEL for developmental toxicity was the highest tested dose (1000 mg/kg bw/day).