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Clinical Trial
. 2003 Dec;56(6):670-8.
doi: 10.1046/j.1365-2125.2003.01908.x.

Diltiazem co-treatment in renal transplant patients receiving microemulsion cyclosporin

Affiliations
Clinical Trial

Diltiazem co-treatment in renal transplant patients receiving microemulsion cyclosporin

Cyrus R Kumana et al. Br J Clin Pharmacol. 2003 Dec.

Abstract

Background: Usage of cyclosporin (the Hong Kong Hospital Authority's single largest item of drug expenditure) continues to increase, mainly due to increasing numbers of renal allograft patients taking it as long-term antirejection therapy. Diltiazem, an antihypertensive agent, interferes with the first pass extraction of oral cyclosporin, thus serving to conserve its dosage.

Aims: In renal transplant patients, to assess whether diltiazem co-treatment could achieve worthwhile dosage conservation of Neoral (a relatively new microemulsified cyclosporin formulation), safely.

Methods: A randomized, placebo-controlled, double-blind clinical trial was undertaken at three local hospitals. Renal transplant recipients receiving Neoral as prophylactic immunosuppression were randomized to two treatment arms. Active treatment consisted of diltiazem tablets 30 or 60 mg twice daily for patients weighing < 60 or >or= 60 kg, respectively. One hundred and ten eligible patients gave their informed consent, and were followed up for at least six months. The mean difference in the dollar cost in the sixth month was the primary outcome. Secondary/ancillary outcomes included changes in cyclosporin dosage and blood level, and untoward clinical events including rejection. Outcomes were evaluated by intention to treat analyses.

Results: During weeks 23-26 (sixth month) post randomization, diltiazem co-treatment yielded an estimated average cost saving per patient on drugs of 15%[the 95% confidence interval (CI) of the difference being HK dollars 609 +/- 517 or pound 50 +/- 42], with no apparent excess of untoward or adverse events, complications, hospitalization, outpatient visits, or inferior quality of life.

Conclusions: This diltiazem co-treatment regime applied to the nearly 1800 surviving renal allograft patients followed up in Hospital Authority hospitals could have saved approximately HK dollars 14.3 million ( pound 1.17 million) annually, without adverse sequelae.

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Figures

Figure 1
Figure 1
Cyclosporin dosage change from baseline (1–2 weeks) to weeks 23–26 (6th month) in individuals (55 in each group.) Diltiazem (formula image) and Placebo (▪).

References

    1. Kronbach T, Fisher V, Meyer UA. Cyclosporine metabolism in human liver: identification of a cytochrome P450III gene family as the major cyclosporine-metabolizing enzyme explains interactions of cyclosporine with other drugs. Clin Pharmacol Ther. 1988;43:630–635. - PubMed
    1. Shaw LM. Advances in cyclosporine pharmacology, measurement and therapeutic monitoring. Clin Chem. 1989;35:1299–1308. - PubMed
    1. Lindholm A, Henricsson S, Dahlqvist R. The effect of food and bile acid administration on the relative bioavailability of cyclosporin. Br J Clin Pharmacol. 1990;29:541–548. - PMC - PubMed
    1. Kolars JC, Awni WM, Merion RM, Watkins PB. First-pass metabolism of cyclosporin by the gut. Lancet. 1991;338:1488–1490. - PubMed
    1. Herbert MF, Roberts JP, Prueksaritanont T, Benet LZ. Bioavailability of cyclosporine with concomitant rifampin administration is markedly less than predicted by hepatic enzyme induction. Clin Pharmacol Ther. 1992;52:453–457. - PubMed

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