Thiotepa

N,N'N'-triethylenethiophosphoramide (ThioTEPA) is a cancer chemotherapeutic member of the alkylating agent group, now in use for over 50 years. It is a stable derivative of N,N',N''- triethylenephosphoramide (TEPA). It is mostly used to treat breast cancer, ovarian cancer and bladder cancer. It is also used as conditioning for Bone marrow transplantation. Its main toxicity is myelosuppression.

Thiotepa is an alkylating agent used to prevent graft rejection in stem cell transplantation and to treat a variety of malignancies including certain types of adenocarcinoma and superficial bladder carcinomas.

ThioTEPA is used a as conditioning treatment prior to allogeneic or autologous haematopoietic progenitor cell transplantation (HPCT) in haematological diseases in adult and paediatric patients. Also, when high dose chemotherapy with HPCT support it is appropriate for the treatment of solid tumours in adult and paediatric patients.

• Adenocarcinoma of the Ovaries
• Breast Adenocarcinoma
• Papillary transitional cell carcinoma of bladder
• Malignant effusion

The unstable nitrogen-carbon groups alkylate with DNA causing irrepairable DNA damage. They stop tumor growth by crosslinking guanine nucleobases in DNA double-helix strands, directly attacking DNA. This makes the strands unable to uncoil and separate. As this is necessary in DNA replication, the cells can no longer divide. These drugs act nonspecifically.

The alkyl group is attached to the guanine base of DNA, at the number 7 nitrogen atom of the imidazole ring. They stop tumor growth by crosslinking guanine nucleobases in DNA double-helix strands, directly attacking DNA. This makes the strands unable to uncoil and separate. As this is necessary in DNA replication, the cells can no longer divide. These drugs act nonspecifically.

Urinary excretion of 14C-labeled thiotepa and metabolites in a 34-year old patient with metastatic carcinoma of the cecum who received a dose of 0.3 mg/kg intravenously was 63%.

1.5 to 4.1 hours

• 446 +/- 63 mL/min [female patients (45 to 84 years) with advanced stage ovarian cancer receiving 60 mg and 80 mg thiotepa by intravenous infusion on subsequent courses given at 4-week intervals]

• Exercise caution with grapefruit products. Grapefruit inhibits the CYP3A4 metabolism of thiotepa, which may increase its serum concentration.
• Exercise caution with St. John's Wort. This herb induces CYP3A4 metabolism and may reduce serum levels of thiotepa.

• Haematological diseases: The recommended dose in haematological diseases ranges from 125 mg/m2/day (3.38 mg/kg/day) to 300 mg/m2/day (8.10 mg/kg/day) as a single daily infusion, administered from2up to 4 consecutive days before autologous HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 900 mg/m2(24.32 mg/kg), during the time of the entire conditioning treatment.
• Lymphoma: The recommended dose ranges from 125 mg/m2/day (3.38 mg/kg/day) to 300 mg/m2/day (8.10 mg/kg/day) as a single daily infusion, administered from2up to 4 consecutive days before autologous HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 900 mg/m2(24.32 mg/kg), during the time of the entire conditioning treatment.
• Central nervous system lymphoma: The recommended dose is 185 mg/m2/day (5 mg/kg/day) as a single daily infusion, administered for 2 consecutive days before autologous HPCT, without exceeding the total maximum cumulative dose of 370 mg/m2(10 mg/kg), during the time of the entire conditioning treatment.
• Multiple myeloma: The recommended dose ranges from 150 mg/m2/day (4.05 mg/kg/day) to 250 mg/m2/day (6.76 mg/kg/day) as a single daily infusion, administered for 3 consecutive days before autologous HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 750 mg/m2(20.27 mg/kg), during the time of the entire conditioning treatment.

• Breast cancer: The recommended dose ranges from 120 mg/m2/day (3.24 mg/kg/day) to 250 mg/m2/day (6.76 mg/kg/day) as a single daily infusion, administered from 3 up to 5 consecutive days before autologous HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 800 mg/m2(21.62 mg/kg), during the time of the entire conditioning treatment.
• CNS tumours: The recommended dose ranges from 125 mg/m2/day (3.38 mg/kg/day) to 250 mg/m2/day (6.76 mg/kg/day) divided in one or two daily infusions, administered from 3 up to 4 consecutive days before autologous HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 750 mg/m2(20.27 mg/kg), during the time of the entire conditioning treatment.
• Ovarian cancer: The recommended dose is 250 mg/m2/day (6.76 mg/kg/day) as a single daily infusion, administered in 2 consecutive days before autologous HPCT, without exceeding the total maximum cumulative dose of 500 mg/m2(13.51 mg/kg), during the time of the entire conditioning treatment.
• Germ cell tumours: The recommended dose ranges from 150 mg/m2/day (4.05 mg/kg/day) to 250 mg/m2/day (6.76 mg/kg/day) as a single daily infusion, administered for 3 consecutive days before autologous HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 750 mg/m2(20.27 mg/kg), during the time of the entire conditioning treatment.

• Haematological diseases: The recommended dose in haematological diseases ranges from 185 mg/m2/day (5 mg/kg/day) to 481 mg/m2/day (13 mg/kg/day) divided in one or two daily infusions, administered from 1 up to 3 consecutive days before allogeneic HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 555 mg/m2(15 mg/kg), during the time of the entire conditioning treatment.
• Lymphoma: The recommended dose in lymphoma is 370 mg/m2/day (10 mg/kg/day) divided in two daily infusions before allogeneic HPCT, without exceeding the total maximum cumulative dose of 370 mg/m2(10 mg/kg), during the time of the entire conditioning treatment.
• Multiple myeloma: The recommended dose is 185 mg/m2/day (5 mg/kg/day) as a single daily infusion before allogeneic HPCT, without exceeding the total maximum cumulative dose of 185 mg/m2(5 mg/kg), during the time of the entire conditioning treatment.
• Leukaemia: The recommended dose ranges from 185 mg/m2/day (5 mg/kg/day) to 481 mg/m2/day (13 mg/kg/day) divided in one or two daily infusions, administered from 1 up to 2 consecutive days before allogeneic HPCT depending on the combination with other chemotherapeutic medicinal products, without exceeding the total maximum cumulative dose of 555 mg/m2(15 mg/kg), during the time of the entire conditioning treatment.
• Thalassemia: The recommended dose is 370 mg/m2/day (10 mg/kg/day) divided in two daily infusions, administered before allogeneic HPCT, without exceeding the total maximum cumulative dose of 370 mg/m2(10 mg/kg), during the time of the entire conditioning treatment.