Registration Dossier

Toxicological information

Developmental toxicity / teratogenicity

Currently viewing:

Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
Developmental toxicity of meglumine antimoniate and transplacental transfer of antimony in the rat
Author:
Elaine S. Miranda, Norbert Miekeley, Rosangel R. De-Carvalho, Francisco J.R. Paumgartten
Year:
2006
Bibliographic source:
Reproductive Toxicology 21 (2006) 292–300

Materials and methods

Principles of method if other than guideline:
The experimental setup is similar to the OECD 414, but no maternal toxicity at highest dose, proof of exposure by measurement of substance in blood mother and fetusses.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Specific details on test material used for the study:
Meglumine antimoniate (Glucantime®, Aventis Pharma, lot 104557)
The injected solution contained MA at 85mg SbV/mL
the injected volumes were adjusted to obtain the administered dose

Test animals

Species:
rat
Strain:
Wistar
Details on test animals and environmental conditions:
Male and nulliparous female Wistar rats of the colony maintained by the
Centre for Breeding of Laboratory Animals of Oswaldo Cruz Foundation (CECAL-FIOCUZ), approximately 80 days old, were used in the experiments. The rats were individually housed in standard plastic cages with stainless steel coverlids and pinewood shavings as bedding, and kept in an animal room with controlled environmental conditions (12-h light:12-h dark cycle, lights
on from 8:00 to 20:00 h; temperature 22±1 ◦C; relative humidity approx- imately 70%). Animals were given free access to a pelleted diet for rats and mice (CR1 Nuvital, Nuvilab Ltd., Curitiba, PR, Brazil) and tap water.

Administration / exposure

Route of administration:
subcutaneous
Vehicle:
other: potassium metabisulfite 1.6mg/mL and sodium sulfite 0.18 mg/mL
Details on exposure:
injection on the back skin of the rats
daily from GD o till Gd 20.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Exposure was confirmed by measurement of the compound in the blood of Dam - every other day and in fetusses at day 21.
ICP-MS - the method was validated by analysis of certified reference materials.
Details on mating procedure:
Mating was carried out by placing two females into the cage of one male for2 h (6:00–8:00 h) and confirmed by the presence of sperm in the vaginal smear. T
he day on which spermatozoa were detected in the smear was designated as day 0 of pregnancy
Duration of treatment / exposure:
from GD 0 - GD 20
Frequency of treatment:
daily
Duration of test:
21 days
Doses / concentrationsopen allclose all
Dose / conc.:
0 other: untreated
Remarks:
untreated control
Dose / conc.:
0 mg/kg bw/day (actual dose received)
Remarks:
vehicle control
Dose / conc.:
75 mg/kg bw/day (actual dose received)
Remarks:
Sb V
Dose / conc.:
150 mg/kg bw/day (actual dose received)
Remarks:
SbV
Dose / conc.:
300 mg/kg bw/day (actual dose received)
Remarks:
SbV
No. of animals per sex per dose:
untreated controles: 21
vechilce control :20
75 mg Sb V : 19
150 mgSb V: 21
300mg Sb V: 20
Control animals:
yes
yes, concurrent no treatment
yes, concurrent vehicle
Details on study design:
standard experimental design - cfr OECD 414
extra animals were included to perform toxicokinetics during Day 1 of treatment

Examinations

Statistics:
Data were evaluated either by one-way analysis of variance (ANOVA)and the Duncan post hoc test, or by the Kruskal–Wallis test followed by the Mann–Whitney U-test whenever the data did not fit a normal distribution. Pro- portions were analysed either by the Chi-square test, or by the Fisher exact test if any expected frequencywas smaller than 5. Statistical analysiswas performed using MINITAB Software (MTB, University of Pennsylvania, 1984) and a difference was considered as statistically significan t at P<0.05.

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
the reduction in weight gain of the dams at the higest concentration seemed to be, at least in part, due to embryotoxicity.
Food efficiency:
not examined
Ophthalmological findings:
not examined
Haematological findings:
not examined
Clinical biochemistry 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:
no effects observed
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
not examined
Histopathological findings: neoplastic:
not examined
Other effects:
no effects observed

Maternal developmental toxicity

Number of abortions:
no effects observed
Pre- and post-implantation loss:
no effects observed
Total litter losses by resorption:
effects observed, treatment-related
Description (incidence and severity):

litter median (87,5%) significantly different from non-treated, vecicle control and 75mg dose groups.
Early or late resorptions:
effects observed, treatment-related
Description (incidence and severity):
reduced number of resorptions in the highest test group (12,5%) --different from untreated control
Dead fetuses:
no effects observed
Changes in pregnancy duration:
no effects observed
Description (incidence and severity):
Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): no effects observed
Changes in number of pregnant:
no effects observed
Other effects:
no effects observed

Results (fetuses)

Fetal body weight changes:
effects observed, treatment-related
Description (incidence and severity):
the fetal body weight was only reduced in the highest dose group (P < 0.05 compared to all other groups).
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:
no effects observed
Description (incidence and severity):
liter mean was not different in the different groups.
Changes in sex ratio:
no effects observed
Changes in litter size and weights:
not examined
Changes in postnatal survival:
not examined
External malformations:
no effects observed
Skeletal malformations:
no effects observed
Description (incidence and severity):
differencesin the range of historical controles
Visceral malformations:
no effects observed
Description (incidence and severity):
differences were in the range of historical controles.
Other effects:
effects observed, treatment-related
Description (incidence and severity):
dose related reduction in both the absolute and relative liver weights.

Effect levels (fetuses)

Key result
Dose descriptor:
NOEL
Effect level:
>= 75 - < 150 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
not specified
Basis for effect level:
reduction in number of live offspring

Applicant's summary and conclusion

Conclusions:
Embryotoxicity, reductions in fetal weight and some skeletal and soft tissue abnormalities at 300 mg/kg/bw Sb(V). NOAEL for embryotoxicity set at 75 mg/kg bw Sb(V) due to observation of minor effects at 150 mg/kg bw/day. No maternal toxicity said to be present, but significant reductions in maternal weight gain were evident at highest dose tested and indicate onset of maternal toxicity.
Executive summary:

Meglumine antimoniate (MA), a pentavalent antimonial (SbV) drug, has been used for the treatment of leishmaniases for over half a century

but there is almost no data on its safety and kinetics during pregnancy. This study was undertaken to investigate the developmental toxicity ofMA as well as the transplacental transfer of antimony (Sb) in rats. Wistar rats (approximately 20 per group) were treated subcutaneously (s.c.) with MA (0, 75, 150, 300mgSbV/(kgBWday)) during pregnancy (days 1–20). An untreated control group was evaluated as well. Caesarean sections were performed on day 21 and implantations, living and dead fetuses, and resorptions were recorded. Fetuses were weighed and fixed in Bouin’s solution and one-third of each litterwas examined for soft-tissue anomalies. The remaining fetuses were cleared and stained with Alizarin red S for skeleton evaluation. No adverse effect ofMAon the mothers was noted at any dose level. No embryotoxicity was observed at the lowest dose but, at the highest dose,MAincreased embryolethality, reduced fetal weight and augmented the occurrence of some soft-tissue and skeleton variations. Therefore, the no-observed-adverse-effect level for MA-induced embryotoxicity was 75mgSbV/(kgBWday). In a separate group of rats treated with 300mgSbV/(kgBWday) s.c. during whole pregnancy, blood (0.2mL) was taken from the tail vein 1, 2, 4, 6, 12 and 24 h after treatment on day 1 and thereafter every other day immediately before drug injection. Blood was also taken from fetuses removed on day 21, 24 h after the last injection of MA. Blood levels of Sb were determined by ICP-MS and results showed that most of administered Sb was eliminated rapidly (in less than 6 h), but nadir blood concentrations increased gradually during treatment from 1 to 2?g/g, 24 h after the first dose, up to approximately 38?g/g after the 20th dose. Levels of Sb in fetal blood were as high as 10–15?g/g, i.e. approximately 30% their mothers’ nadir levels near term. These findings indicated that repeated administration of MA during gestation led to an accumulation of Sb in mothers and fetuses.