bin all showed mean increases over baseline in the untreated group which were significantly larger than with the patients treated with trientine hydrochloride. In the 13 patients treated with trientine hydrochloride, previous symptoms and signs relating to d-penicillamine intolerance disappeared in 8 patients, improved in 4 patients, and remained unchanged in one patient. The neurological status in the trientine hydrochloride group was unchanged or improved over baseline, whereas in the untreated group, 6 patients remained unchanged and 6 worsened. Kayser-Fleischer rings improved significantly during trientine hydrochloride treatment.
The clinical outcome of the two groups also differed markedly. Of the 13 patients on therapy with trientine hydrochloride (mean duration of therapy 4.1 years; range 1 to 13 years), all were alive at the data cutoff date, and in the non-treated group (mean years with no therapy 2.7 years; range 3 months to 9 years), 9 of the 12 died of hepatic disease.
Chelating Properties
Preclinical Studies
Studies in animals have shown that trientine hydrochloride has cupriuretic activities in both normal and copper-loaded rats. In general, the effects of trientine hydrochloride on urinary copper excretion are similar to those of equimolar doses of penicillamine, although in one study they were significantly smaller.
Human Studies
Renal clearance studies were carried out with penicillamine and trientine hydrochloride on separate occasions in selected patients treated with penicillamine for at least one year. Six-hour excretion rates of copper were determined off treatment and after a single dose of 500 mg of penicillamine or 1.2 g of trientine hydrochloride. The mean urinary excretion rates of copper were as follows:
No. of
Patients Single Dose Treatment Basal Excretion Rate
(µg Cu + + /6hr) Test-dose Excretion Rate
(µg Cu + + /6hr)
6 Trientine, 1.2 g 19 234
4 Penicillamine, 500mg 17 320
In patients not previously treated with chelating agents, a similar comparison was made:
No. of Patients Single Dose Treatment Basal Excretion Rate
(µg Cu + + /6hr) Test-dose Excretion Rate
(µg Cu + + /6hr)
8 Trientine, 1.2 g 71 1326
7 Penicillamine, 500mg 68 1074
These results demonstrate that Syprine is effective as a cupriuretic agent in patients with Wilson's disease although on a molar basis it appears to be less potent or less effective than penicillamine. Evidence from a radio-labelled copper study indicates that the different cupriuretic effect between these two drugs could be due to a difference in selectivity of the drugs for different copper pools within the body.
Pharmacokinetics
Data on the pharmacokinetics of trientine hydrochloride are not available. Dosage adjustment recommendations are based upon clinical use of the drug (see DOSAGE AND ADMINISTRATION).
Indications and Usage for Syprine
Syprine is indicated in the treatment of patients with Wilson's disease who are intolerant of penicillamine. Clinical experience with Syprine is limited and alternate dosing regimens have not been well-characterized; all endpoints in determining an individual patient's dose have not been well defined. Syprine and penicillamine cannot be considered interchangeable. Syprine should be used when continued treatment with penicillamine is no longer possible because of intolerable or life endangering side effects.
Unlike penicillamine, Syprine is not re |
