-5%
Cyclophosphamide undergoes biotransformation in the liver, where it is converted into active alkylating metabolites by a mixed-function microsomal oxidase system. These metabolites inhibit the growth of rapidly dividing malignant cells by cross-linking tumor cell DNA.
Cyclophosphamide is well absorbed orally, with a bioavailability exceeding 75%. Following intravenous administration, peak plasma concentrations of metabolites occur within 2 to 3 hours. The elimination half-life of the unchanged drug ranges from 3 to 12 hours. Excretion primarily occurs via metabolites, with 5-25% of the dose eliminated as an unchanged drug in urine. Some metabolites bind to plasma proteins (>60%). No single metabolite has been identified as solely responsible for therapeutic or toxic effects.
While elevated metabolite levels have been observed in patients with renal impairment, there is no consistent evidence of increased clinical toxicity.
Neoclomide, while effective as a standalone treatment for certain malignancies, is more commonly administered in combination or sequence with other antineoplastic drugs. It is often used in the treatment of the following conditions:
- Malignant Lymphomas (Stages III and IV, Ann Arbor staging system): Hodgkin’s disease, lymphocytic lymphoma (nodular or diffuse), mixed-cell type lymphoma, histiocytic lymphoma, Burkitt’s lymphoma.
- Multiple Myeloma
- Leukemias: Chronic lymphocytic leukemia, chronic granulocytic leukemia (not effective in acute blastic crisis), acute myelogenous and monocytic leukemia, and acute lymphoblastic (stem-cell) leukemia in children (effective in prolonging remission).
- Mycosis fungoides: Advanced stages of the disease.
- Neuroblastoma: Disseminated disease.
- Adenocarcinoma of the Ovary
- Retinoblastoma
- Carcinoma of the Breast
Nonmalignant Disease:
In children, Neoclomide can be used to treat biopsy-proven “minimal change” nephrotic syndrome when corticosteroid therapy fails to produce adequate results or causes intolerable side effects. However, it should not be considered first-line therapy and is not indicated for nephrotic syndrome in adults or other renal conditions.
Use only as directed by a registered physician.
Side Effects
- Digestive System: Commonly causes nausea and vomiting. Less frequent effects include anorexia, abdominal discomfort, diarrhea, hemorrhagic colitis, oral ulcers, and jaundice. These effects typically resolve upon discontinuation of treatment.
- Skin: Alopecia is common, with hair regrowth during or after treatment, sometimes with altered texture or color. Rash, pigmentation changes, and nail alterations can occur. Rarely, Stevens-Johnson syndrome and toxic epidermal necrolysis have been reported.
- Hematopoietic System: Leukopenia is common and dose-dependent, with reductions below 2000 cells/mm³ associated with increased infection risk. Thrombocytopenia and anemia occur occasionally and are reversible upon dosage adjustment or treatment cessation.
- Urinary System: Hemorrhagic ureteritis and renal tubular necrosis have been reported, usually resolving after discontinuation of therapy.
- Respiratory System: Rare cases of interstitial pneumonitis and pulmonary fibrosis have been noted with prolonged high-dose use.
Other: Anaphylaxis, SIADH (syndrome of inappropriate antidiuretic hormone secretion), malaise, and asthenia have been reported.
- Pregnancy: Category D. Cyclophosphamide is excreted in breast milk and may cause adverse effects and tumorigenicity in infants. Nursing should be discontinued during treatment, or the drug should be stopped if breastfeeding is essential.