Thiotepa Drug Information

Thiotepa for Injection, USP has been tried with varying results in the palliation of a wide variety of neoplastic diseases. However, the most consistent results have been seen in the following tumors: 1. Adenocarcinoma of the breast. 2. Adenocarcinoma of the ovary. 3. For controlling intracavitary effusions secondary to diffuse or localized neoplastic diseases of various serosal cavities. 4. For the treatment of superficial papillary carcinoma of the urinary bladder. While now largely superseded by other treatments, thiotepa has been effective against other lymphomas, such as lymphosarcoma and Hodgkin’s disease.

In addition to its effect on the blood-forming elements (see WARNINGS and PRECAUTIONS sections), thiotepa may cause other adverse reactions. General: Fatigue, weakness. Febrile reaction and discharge from a subcutaneous lesion may occur as the result of breakdown of tumor tissue.

Hypersensitivity Reactions: Allergic reactions - rash, urticaria, laryngeal edema, asthma, anaphylactic shock, wheezing. Local Reactions: Contact dermatitis, pain at the injection site. Gastrointestinal: Nausea, vomiting, abdominal pain, anorexia.

Renal: Dysuria, urinary retention. There have been rare reports of chemical cystitis or hemorrhagic cystitis following intravesical, but not parenteral administration of thiotepa. Respiratory: Prolonged apnea has been reported when succinylcholine was administered prior to surgery, following combined use of thiotepa and other anticancer agents.

It was theorized that this was caused by decrease of pseudocholinesterase activity caused by the anticancer drugs. Neurologic: Dizziness, headache, blurred vision. Skin: Dermatitis, alopecia.

Skin depigmentation has been reported following topical use. Special Senses: Conjunctivitis. Reproductive: Amenorrhea, interference with spermatogenesis.

Drug Interactions It is not advisable to combine, simultaneously or sequentially, cancer chemotherapeutic agents or a cancer chemotherapeutic agent and a therapeutic modality having the same mechanism of action. Therefore, thiotepa combined with other alkylating agents such as nitrogen mustard or cyclophosphamide or thiotepa combined with irradiation would serve to intensify toxicity rather than to enhance therapeutic response. If these agents must follow each other, it is important that recovery from the first agent, as indicated by white blood cell count, be complete before therapy with the second agent is instituted.

Other drugs which are known to produce bone-marrow depression should be avoided.

Pregnancy Category D: See WARNINGS section. Thiotepa can cause fetal harm when administered to a pregnant woman. Thiotepa given by the IP route was teratogenic in mice at doses ≥ 1 mg/kg (3.2 mg/m 2 ), approximately 8-fold less than the maximum recommended human therapeutic dose based on body-surface area.

Thiotepa given by the IP route was teratogenic in rats at doses ≥ 3 mg/kg (21 mg/m 2 ), approximately equal to the maximum recommended human therapeutic dose based on body-surface area. Thiotepa was lethal to rabbit fetuses at a dose of 3 mg/kg (41 mg/m 2 ), approximately 2 times the maximum recommended human therapeutic dose based on body-surface area. Patients of childbearing potential should be advised to avoid pregnancy.

There are no adequate and well-controlled studies in pregnant women. If thiotepa is used during pregnancy, or if pregnancy occurs during thiotepa therapy, the patient and partner should be apprised of the potential hazard to the fetus.

Pediatric Use Safety and effectiveness in pediatric patients have not been established.

Thiotepa is contraindicated in patients with a known hypersensitivity (allergy) to this preparation. Therapy is probably contraindicated in cases of existing hepatic, renal, or bone-marrow damage. However, if the need outweighs the risk in such patients, thiotepa may be used in low dosage, and accompanied by hepatic, renal and hemopoietic function tests.

Hematopoietic toxicity can occur following overdose, manifested by a decrease in the white cell count and/or platelets. Red blood cell count is a less accurate indicator of thiotepa toxicity. Bleeding manifestations may develop.

The patient may become more vulnerable to infection, and less able to combat such infection. Dosages within and minimally above the recommended therapeutic doses have been associated with potentially life-threatening hematopoietic toxicity. Thiotepa has a toxic effect on the hematopoietic system that is dose related.

Thiotepa is dialyzable. There is no known antidote for overdosage with thiotepa. Transfusions of whole blood or platelets have proven beneficial to the patient in combating hematopoietic toxicity.