Tetraammineplatinum (II) diacetate

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

3 to 31 May 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, to GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Version / remarks:

based on the 1995 Test Guideline.

Deviations:

yes

Remarks:

deviations from maximum level of humidity and deviations in dosing time on day 5. These changes were not thought to affect the integrity of the study.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.7 (Repeated Dose (28 Days) Toxicity (Oral))

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3050 (repeated dose 28-day oral toxicity study in rodents)

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Platinum(2+)tetraammine(SP-4-1) diacetate

IUPAC Name:

Platinum(2+)tetraammine(SP-4-1) diacetate

Constituent 2

Reference substance name:

127733-97-5

Cas Number:

127733-97-5

IUPAC Name:

127733-97-5

Details on test material:

- Name of test material (as cited in study report): platinum(2+)tetraammine(SP-4-1) diacetate
- Substance type: no data
- Physical state: white crystalline powder with lumps
- Analytical purity: 46.95% (Pt)
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: no data
- Isomers composition: no data
- Purity test date: no data
- Lot/batch No.: AP013/06
- Expiration date of the lot/batch: 20 March 2007
- Stability under test conditions: at least 5 hours
- Storage condition of test material: at room temperature in the dark

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: approximately 6 weeks
- Weight at study initiation: within +/- of the sex mean
- Fasting period before study: no data
- Housing: groups of five animals per sex
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.6 to 23.6
- Humidity (%): 39 to 92 [OECD reccomends 30 to 70%]
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: To: no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

Milli-U

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Formulations were prepared daily within 4 hours of dosing. The test substance was homogenised in Milli-U waterto a "visually acceptable" level [on days 6, 14, 25 and 28, the maximum time between formulation and dosing was exceeded by approximately 1.5 hours]. Animals were dosed at a similar time each day,within four hours of each other [this was exceeded by approximately 30 minutes on day 5]

DIET PREPARATION
- Rate of preparation of diet (frequency): n/a
- Mixing appropriate amounts with (Type of food): n/a
- Storage temperature of food: n/a

VEHICLE
- Justification for use and choice of vehicle (if other than water): n/a
- Concentration in vehicle: n/a
- Amount of vehicle (if gavage): 5 ml/kg body weight
- Lot/batch no. (if required): n/a
- Purity: n/a

Details on analytical verification of doses or concentrations:

Accuracy of doses for groups 2 and 3 (given 50 and 150 mg/kg bw/day respectively) were within the range of 102 to 107%. Accuracy for group 4 (given 1000 mg/kg bw/day) was within the range of 116 to 119% (slightly above the nominal range of 100 +/- 10%). This was considered sufficient for the purpose of the study.

Duration of treatment / exposure:

at least 28 days

Frequency of treatment:

once daily, seven days a week

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
0
Basis:
other: nominal: gavage

Doses / concentrations 2

Remarks:

Doses / Concentrations:
50 mg/kg bw/day
Basis:
other: nominal: gavage

Doses / concentrations 3

Remarks:

Doses / Concentrations:
150 mg/kg bw/day
Basis:
other: nominal: gavage

Doses / concentrations 4

Remarks:

Doses / Concentrations:
1000 mg/kg bw/day
Basis:
other: nominal: gavage

No. of animals per sex per dose:

5

Details on study design:

- Dose selection rationale: the test doses were selected based on the results of a 5-day preliminary range-finding study (results not presented)
- Rationale for animal assignment (if not random): n/a
- Rationale for selecting satellite groups: none were selected
- Post-exposure recovery period in satellite groups: n/a
- Section schedule rationale (if not random): no data

Positive control:

No postive control

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: at least twice daily
- Mortality and viability observations were included.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at least once daily (see "any other information on materials and methods incl. tables")

BODY WEIGHT: Yes
- Time schedule for examinations: on days 1, 8, 15, 22 and 28

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: n/a

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): n/a
- Time schedule for examinations: n/a

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: immediately prior to post mortem
- Anaesthetic used for blood collection: iso-flurane
- Animals fasted: Yes (24 hours)
- How many animals: 5/sex/dose group
- Parameters checked in table [No.1] were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: immediately prior to post mortem
- Animals fasted: Yes (24 hours)
- How many animals: 5/sex/dose group
- Parameters checked in table [No.2] were examined.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: during week 4
- Dose groups that were examined: all surviving animals
- Battery of functions tested: sensory activity / grip strength / motor activity / reflexes (pupillary, righting)

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see table [No.3])
HISTOPATHOLOGY: Yes (see table [No.3])

Other examinations:

The following organ weights (and terminal body weight) were recorded from the surving animals on the scheduled day of necropsy:
Adrenal glands
Brain
Epididymides
Heart
Kidneys
Liver
Spleen
Testes
Thymus

Statistics:

The Dunnett test (many-to-one t-test) was applied to the treated and control groups for each sex if the variables could be assumed to follow a normal distribution.
The Steel test (many-to-one rank test) was applied when the data could not be assumed to follow a normal distribution.
For frequency data, the exact Fisher test was applied.
In all cases, two-tailed tests were used, with p < 0.05 being the lowest level of significance.

Results and discussion

Results of examinations

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

in rats surviving up to scheduled necropsy

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

in rats surviving up to scheduled necropsy

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY
Rats given 1000 mg/kg bw/day: all rats were sacrificed on day 6 due to poor clinical condition.
Rats given 50 or 150 mg/kg bw/day: no mortality occurred.

BODY WEIGHT AND WEIGHT GAIN
Rats given 1000 mg/kg bw/day: weight loss of up to approximately 25% was observed (measured on day six).
Rats given 50 or 150 mg/kg bw/day: no significant changes were observed relative to the control group.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
Rats given 1000 mg/kg bw/day: food consumption was severely reduced.
Rats given 50 or 150 mg/kg bw/day: no significant changes were observed relative to the control group.

FOOD EFFICIENCY
Not examined.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study)
Not examined.

OPHTHALMOSCOPIC EXAMINATION
Not examined.

HAEMATOLOGY
Rats given 1000 mg/kg bw/day: not examined (due to mortality).
The following findings were not judged to be toxicologically significant:
Rats given 150 mg/kg bw/day: a statistically significant reduction in reticulocyte count was observed in males relative to the control group, but the change was slight and occurred in the absence of a similar change in red blood cell count.
Rats given 50 mg/kg bw/day: a statistically significant reduction in RDW of females lacked a dose-response relationship.

CLINICAL CHEMISTRY
Rats given 1000 mg/kg bw/day: not examined (due to mortality).
The following findings lacked dose-response, and/or the means were within the normal range encountered in rats of this age and strain:
Rats given 150 mg/kg bw/day: statistically significant changes relative to the control group included higher calcium levels in females.
Rats given 50 mg/kg bw/day: statistically significant changes relative to the control group included lower urea, glucose and calcium levels, higher chloride levels in males, and lower total protein levels in females.

URINALYSIS
Not examined.

NEUROBEHAVIOUR
No adverse effects were observed.

ORGAN WEIGHTS
Rats given 1000 mg/kg bw/day: weights of brain, heart, liver, thymus, kidney, spleen, testes and epididymides were significantly reduced.
Rats given 50 or 150 mg/kg bw/day: no significant changes in the weights of analysed organs were observed.

GROSS PATHOLOGY
Rats given 1000 mg/kg bw/day: commonly an overfilled stomach was seen. At a lower incidence, pale discolouration of the gastro-intestinal tract and caecum, red discolouration of the ileum, red foci on the caecum and thickening of the caecum and colon was observed. Animals were also considered to be emaciated.
Rats given 50 or 150 mg/kg bw/day: no toxicologically relevant alterations were observed.

HISTOPATHOLOGY: NON-NEOPLASTIC
Rats given 1000 mg/kg bw/day: possible indicators of organ toxicity were seen in the spleen, bone marrow (sternal) and thymus.
- Spleen: slight to moderate red pulp atrophy in nine animals, slight lymphoid atrophy in six animals
- Bone marrow - sternal: minimal to moderate myeloid atrophy in seven animals
- Thymus: slight to severe lymphoid atrophy - involution in nine animals
A number of other findings were considered to be unrelated to treatment.
Rats given 50 or 150 mg/kg bw/day: no adverse effects were observed, relative to the control group.

HISTOPATHOLOGY: NEOPLASTIC (if applicable)
No neoplasticity was observed.

HISTORICAL CONTROL DATA (if applicable)
Not provided.

Effect levels

Dose descriptor:

NOAEL

Effect level:

150 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects seen at 50 or 150 mg/kg bw/day. Effects on clinical signs; body weight; food consumption; gross pathology; organ weights; and histopathology at 1000 mg/kg bw/day.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

In a repeated dose oral toxicity study, carried out according to OECD Test Guideline 407 and to GLP, a NOAEL of 150 mg/kg bw/day was determined for tetraammineplatinum(II) diacetate following gavage administration to rats for 28 days.

Executive summary:

The repeated dose toxicity of tetraammineplatinum(II) diacetate was assessed in a 28-day oral study conducted according to GLP and OECD Test Guideline 407.

 

Wistar rats (5/sex/group) were given a daily gavage administration of tetraammineplatinum diacetate at 0 (given water), 50, 150 or 1000 mg/kg bw/day for 28 days. Throughout the study, animals were observed daily for mortality and other overt clinical signs of toxicity. Body weight and food and water consumption were monitored. At the end of the study, blood samples were collected from each surviving rat for the analysis of haematological parameters and clinical chemistry. This was immediately followed by sacrifice and scheduled necropsy, in which a comprehensive range of organs and tissues were examined macroscopically and microscopically.

 

Due to poor clinical condition, all rats given 1000 mg/kg bw/day were sacrificed on day six. The haematological parameters and clinical chemistry of these animals were not examined. In this high dose group, animals showed a marked reduction in weight (up to 25%) and severely reduced food consumption relative to control animals. Post mortem examination showed significant organ weight reductions and adverse effects on the gastro-intestinal tract (an overfilled stomach, discolouration, thickening of the colon) and caecum (discolouration, thickening). Cellular effects, possibly indicative of organ toxicity, were observed in the spleen, sternal bone marrow and thymus.

 

No toxicologically significant adverse effects were observed in rats given 50 or 150 mg/kg bw/day by gavage for 28 days. Therefore, the no-observed-adverse-effect level (NOAEL) was considered to be 150 mg/kg bw/day.