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Toxicological information

Basic toxicokinetics

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Administrative data

basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
No data
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: Not performed according to guideline or GLP, limited details on methods and results. No information on test substance composition or purity.

Data source

Reference Type:
other: proceedings of colloquia
The metabolism of trientine: animal studies
Gibbs, K.R., Walshe, J. M.
Bibliographic source:
Orphan diseases and orphan drugs. - (Fulbright papers; v. 3) I. Chemotherapy. 2. Orphan drugs. I. Scheinberg, Herbert. 11. Walshe, J. M.111. Series. ISBN 0-7190-2295-9 hardback.

Materials and methods

Objective of study:
Test guideline
no guideline followed
Principles of method if other than guideline:
Labelled trientine was administered orally and intrvenous. The animals were killed at times varying from 30 minutes to 71 hours. Radioactivity was estimated in plasma, liver, spleen, kidneys, muscle and gut wall. the gut contents were also examined, as well as stools and urine. In two cases exahled air was analysed by passage over both alkali and acid traps.
GLP compliance:

Test material

Test material form:
Specific details on test material used for the study:
14C labelled triethylene tetramine 4HCI/MW 292. Prepared by the Radiochemical Centre, Amersham, and was shown by their analysis to be 96% pure. The specific activity was 26 pCi/mg (926 kBq/mg).
No further details.

Test animals

other: Norwegian hooded
not specified

Administration / exposure

Route of administration:
other: oral, iv
not specified
Duration and frequency of treatment / exposure:
Labelled trientine was administered orally to fourteen rats, after an overnight fast, twelve in a dose of 26 µCi while two received 100 µCi.
Eight rats were given the drug by the intravenous (tail vein) route in a dose from 2 to 4 µCi.
Doses / concentrations
Doses / Concentrations:
see above
No. of animals per sex per dose:
no data
Control animals:

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:
After oral administartion the percentage absorbed, that is, the 14C detected in carcass and urine, was between 6% and 18%, the partition varying between almost entirely carcass activity at one hour to almost entirely urine activity at seventy-two hours. The maximum recovery in the urine in any single study was 15%. No test substance was exhaled.
After iv administration between 50% and 60% of the labelled test substance was excreted in the urine within 6 hours. 20% was found in the feaces after 48 hours.

Metabolite characterisation studies

Metabolites identified:
Details on metabolites:
In the small gut at least 6 radio active compounds were present. In the plasma filtrate two new bands were found. Both moved slower than the parent compound and one was equal in concentration to the parent compound. The same was observed after incubation of liver and kidney mince with the test compound. Multiple bands of radioactivity were found in urine, with very little of the parent compound remaining but with a rather strong diffuse band moving at approximately half the speed of trientine. This compound has not been found in plasma, liver or kidney preparations.
The observation that the various derivatives of trientine found in urine can be converted back to the parent compound, simply by hydrolysis, strongly suggested that these were conjugates or chelates of trientine.

Applicant's summary and conclusion

Interpretation of results: no bioaccumulation potential based on study results
The compound is poorly abosorbed after oral and iv administration, rapidly conjugated and excreted.
Executive summary:

Studies using 14carbon labelled trientine given to rats indicate that only some 20% of the drug is absorbed from the gut. It was detected in all tissues analysed, with a maximum concentration in the kidneys. It is rapidly excreted in the urine and more slowly in the bile. There is no evidence that the compound is broken down in the body, but biotransformation does occur, probably by acetylation and possibly other forms of conjugation. The conjugates can all be converted back to trientine by acid hydrolysis.