Product information for human medicinal products
TEPA. Co-administration of inducers of cytochrome P450 (such as rifampicin, carbamazepine,
phenobarbital) may increase the metabolism of thiotepa leading to increased plasma concentrations
of the active metabolite. Therefore, during the concomitant use of thiotepa and these medicinal
products, patients should be carefully monitored clinically.
Thiotepa is a weak inhibitor for CYP2B6, and may thereby potentially increase plasma concentrations
of substances metabolised via CYP2B6, such as ifosfamide, tamoxifen, bupropion, efavirenz and
cyclophosphamide. CYP2B6 catalyzes the metabolic conversion of cyclophosphamide to its active
form 4-hydroxycyclophosphamide (4-OHCP) and co-administration of thiotepa may therefore lead to
decreased concentrations of the active 4-OHCP. Therefore, a clinical monitoring should be exercised
during the concomitant use of thiotepa and these medicinal products.
Contraindications of concomitant use
Yellow fever vaccine: risk of fatal generalized vaccine-induced disease.
More generally, live virus and bacterial vaccines must not be administered to a patient receiving an
immunosuppressive chemotherapeutic agent and at least three months must elapse between
discontinuation of therapy and vaccination.
Concomitant use not recommended
Live attenuated vaccines (except yellow fever): risk of systemic, possibly fatal disease. This risk is
increased in subjects who are already immunosuppressed by their underlying disease.
An inactivated virus vaccine should be used instead, whenever possible (poliomyelitis).
Phenytoin: risk of exacerbation of convulsions resulting from the decrease of phenytoin digestive
absorption by cytotoxic medicinal product or risk of toxicity enhancement and loss of efficacy of the
cytotoxic medicinal product due to increased hepatic metabolism by phenytoin.
Concomitant use to take into consideration
Ciclosporine, tacrolimus: excessive immunosuppression with risk of lymphoproliferation.
Alkylating chemotherapeutic agents, including thiotepa, inhibit plasma pseudocholinesterase by 35%
to 70%. The action of succinyl-choline can be prolonged by 5 to 15 minutes.
Thiotepa must not be concurrently administered with cyclophosphamide when both medicinal
products are present in the same conditioning treatment. TEPADINA® must be delivered after the
completion of any cyclophosphamide infusion.
The concomitant use of thiotepa and other myelosuppressive or myelotoxic agents (i.e.
cyclophosphamide, melphalan, busulfan, fludarabine, treosulfan) may potentiate the risk of
haematologic adverse reactions due to overlapping toxicity profiles of these medicinal products.
Interaction common to all cytotoxics
Due to the increase of thrombotic risk in case of malignancy, the use of anticoagulative treatment is
frequent. The high intra-individual variability of the coagulation state during malignancy, and the
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