^ Brain Tumors
Gleostine is indicated for the treatment of patients with primary and metastatic brain tumors following appropriate surgical and/or radiotherapeutic procedures.
^ Pharmacodynamics
The pharmacodynamics of lomustine are unknown.
^ Description
Gleostine (lomustine) is an alkylating drug for oral administration. The chemical name for lomustine is 1-(2-chloro-ethyl)-3-cyclohexyl-1-nitrosourea and the molecular formula is C 9H 16ClN 3O 2. The molecular weight is 233.71. Lomustine is a yellow powder, which is soluble in 10% ethanol (0.05 mg per mL) and in absolute alcohol (70 mg per mL). Lomustine is insoluble in water (<0.05 mg per mL).
The chemical structure is:
Gleostine is supplied as 10 mg, 40 mg, and 100 mg capsules and contains the following inactive ingredients: magnesium stearate NF and mannitol USP. The capsule shells are composed of gelatin and coloring pigments, depending on the strength: titanium dioxide, and/or yellow iron oxide, and/or Indigotine – FD&C Blue2.
^ Overdosage
Overdosage with Gleostine has occurred, including fatal cases [see Dosage and Administration ( 2.1), Warnings and Precautions ( 5.2)]. Overdosage causes severe myelosuppression, as well as abdominal pain, diarrhea, vomiting, anorexia, lethargy, dizziness, abnormal hepatic function, cough, and shortness of breath.
No antidotes exist for Gleostine overdosage.
^ Delayed Myelosuppression
Gleostine causes myelosuppression that can result in fatal infections and bleeding. Myelosuppression from Gleostine is delayed, dose-related, and cumulative. It usually occurs 4 to 6 weeks after drug administration and persists for 1 to 2 weeks. Thrombocytopenia is generally more severe than leukopenia. Cumulative myelosuppression from Gleostine is manifested by greater severity and longer duration of cytopenias.
Monitor blood counts for at least 6 weeks after each dose. Do not give Gleostine more frequently than every 6 weeks. Adjust dose based on nadir blood counts from prior dose [see Dosage and Administration ( 2.3)].
^ Risk Of Overdosage
Fatal toxicity occurs with overdosage of Gleostine. Dispensing or administering more than one dose can lead to fatal toxicity.
Prescribe only one dose at a time. Dispense only enough capsules for one dose. Both physician and pharmacist should emphasize to the patient that only one dose of Gleostine is taken every 6 weeks [see Dosage and Administration ( 2.1) and Overdosage ( 10)].
^ Hepatotoxicity
Hepatic toxicity, manifested by increased levels of transaminases, alkaline phosphatase, and bilirubin occurs with Gleostine.
Monitor liver function.
^3 Dosage Forms And Strengths
Gleostine capsules are available in three strengths, distinguishable by the color of the capsules:
^ Pediatric Use
Pediatric use, including dose, is not based on adequate and well-controlled clinical studies.
^ How Supplied
Gleostine is available in three strengths, distinguishable by the color of the capsules, in individual bottles of 5 capsules each:
^ Storage And Handling
Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Avoid temperatures over 40°C (104°F).
Gleostine is a cytotoxic drug. Follow applicable special handling and disposal procedures. 1
To minimize the risk of dermal exposure, always wear impervious gloves when handling bottles containing Gleostine capsules. Do not break Gleostine capsules; avoid exposure to broken capsules. If dermal contact occurs, wash areas of skin contact immediately and thoroughly.
^ Hodgkin's Lymphoma
Gleostine is indicated as a component of combination chemotherapy for the treatment of patients with Hodgkin's lymphoma whose disease has progressed following initial chemotherapy.
^ Dose Modifications
Perform weekly complete blood counts and withhold each subsequent dose for more than 6 weeks if needed until platelet counts recover to 100,000/mm 3or greater and leukocytes recover to 4000/mm 3or greater [see Warnings and Precautions ( 5.1)] .
Modify each dose of Gleostine according to the hematologic response of the preceding dose as described in Table 1:
^4 Contraindications
None.
^ Geriatric Use
No data in the clinical studies of Gleostine are available for patients 65 years of age and over to determine whether they respond differently than younger patients. Other reported clinical experience has not identified differences in responses between elderly and younger patients. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy.
Lomustine and its metabolites are known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and renal function should be monitored.
^ Pulmonary Toxicity
Pulmonary toxicity characterized by pulmonary infiltrates and/or fibrosis occurs with Gleostine. Patients with a baseline below 70% of the predicted Forced Vital Capacity (FVC) or Carbon Monoxide Diffusing Capacity (DL CO) are at increased risk. The onset of pulmonary toxicity occurs after an interval of 6 months or longer from the start of therapy, with cumulative doses of Gleostine usually greater than 1100 mg/m 2.
Obtain baseline pulmonary function tests prior to initiating treatment and repeat frequently during treatment. Permanently discontinue Gleostine in patients diagnosed with pulmonary fibrosis.
^ Carcinogenesis, Mutagenesis, Impairment Of Fertility
Lomustine is carcinogenic in rats and mice, producing a marked increase in tumor incidence in doses lower than those employed clinically.
In female rats, daily intraperitoneal treatment with lomustine for 2 weeks prior to mating with untreated males resulted in dose dependent decreases in number of corpora lutea and resorption rates with no live births at a dose of 3 mg/kg (approximately 0.14 times the recommended clinical dose of 130 mg/m 2based on body surface area (BSA), or approximately twice the total clinical dose of lomustine over 6 weeks) and decreased pup survival during the first 4 postnatal days at doses greater than or equal to 1.5 mg/kg (a daily dose of approximately 0.06 times the recommended clinical dose of 130 mg/m 2based on BSA or approximately equal to the total clinical dose of lomustine over 6 weeks). Gleostine may also result in decreased male fertility. Intraperitoneal injection of lomustine resulted in decreased fertility in male rats mated to untreated females based on decreased implantations and decreased fetal body weight at weekly doses greater than or equal to 5 mg/kg (approximately 0.23 times the single clinical dose of 130 mg/m 2based on BSA, or approximately equal to the total clinical dose of lomustine over 6 weeks), and increased resorptions at doses greater than or equal to 2.5 mg/kg/week.
^ Recommended Dose
The recommended dose of Gleostine in adult and pediatric patients is 130 mg/m 2taken as a single oral dose every 6 weeks. Round doses to the nearest 10 mg. Give as a single oral dose and do not repeat for at least 6 weeks. Reduce dose to 100 mg/m 2every 6 weeks in patients with compromised bone marrow function. Also reduce dose accordingly when using with other myelosuppressive drugs.
^ Secondary Malignancies
Secondary malignancies, including acute leukemia and myelodysplasia, occur with long term use.
^ Nephrotoxicity
Progressive renal failure with a decrease in kidney size occurs with Gleostine.
Monitor renal function.
^6 Adverse Reactions
The following serious adverse reactions are discussed in greater detail in other sections of the labeling:
The following adverse reactions associated with the use of Gleostine were identified in clinical trials or postmarketing reports. Because these reactions were reported from a population of uncertain size, it is not possible to estimate their frequency, reliability, or establish a causal relationship to drug exposure.
Gastrointestinal disorders:nausea, vomiting, and stomatitis
Ocular disorders:optic atrophy, visual disturbances, and blindness
Neurologic disorders:disorientation, lethargy, ataxia, and dysarthria
Other:alopecia
^Warning: Delayed Myelosuppression And Risk Of Overdosage
DELAYED MYELOSUPPRESSION
Gleostine causes myelosuppression including fatal myelosuppression. Myelosuppression is delayed, dose-related, and cumulative; occurring 4 to 6 weeks after drug administration and persisting for 1 to 2 weeks. Thrombocytopenia is generally more severe than leukopenia. Cumulative myelosuppression from Gleostine is manifested by greater severity and longer duration of cytopenias. Monitor blood counts for at least 6 weeks after each dose. Do not give Gleostine more frequently than every 6 weeks [see Warnings and Precautions ( 5.1), Dosage and Administration ( 2.2, 2.3)] .
RISK OF OVERDOSAGE
PRESCRIBE, DISPENSE, AND ADMINISTER ONLY ENOUGH CAPSULES FOR ONE DOSE. Fatal toxicity occurs with overdosage of Gleostine. Both physician and pharmacist should emphasize to the patient that only one dose of Gleostine is taken every 6 weeks [see Dosage and Administration ( 2.1), Warnings and Precautions ( 5.2), Overdosage ( 10)] .
^ Embryo-fetal Toxicity
Based on animal data and its mechanism of action, Gleostine can cause fetal harm when administered to a pregnant woman. Embryo-fetal toxicity and teratogenicity occurred in rats and rabbits receiving lomustine daily during organogenesis at doses approximately two to four times the total human dose of 130 mg/m 2over 6 weeks (0.18 to 0.27 times the single human dose of 130 mg/m 2) based on body surface area (BSA). Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with Gleostine and for 2 weeks after the final dose. Advise males with female partners of reproductive potential to use effective contraception during treatment with Gleostine and for 3.5 months after the final dose [see Use in Specific Populations ( 8.1, 8.3)] .
^ References
OSHA. http://www.osha.gov/SLTC/hazardousdrugs/index.html.
^ Females And Males Of Reproductive Potential
Contraception
^ Important Prescribing And Dispensing Information
PRESCRIBE ONLY ONE DOSE FOR EACH TREATMENT CYCLE. DO NOT DISPENSE ENTIRE CONTAINER.Dispense only a sufficient number of capsules for one dose.
Confirm the total dose prescribed by the physician and the appropriate combination of capsule strengths.
Dispense only the appropriate number of Gleostine capsules required for the administration of a single dose.
The prescribed dose may consist of two or more different strengths and colors of capsules.
Instruct patients that Gleostine is taken as a single oral dose and will not be repeated for at least 6 weeks. Taking more than the recommended dose causes toxicities, including fatal outcomes [see Warnings and Precautions ( 5.2) and Overdosage ( 10)] .
Gleostine is a cytotoxic drug. Follow applicable special handling and disposal procedures. 1
To minimize the risk of dermal exposure, always wear impervious gloves when handling bottles containing Gleostine capsules. Do not break Gleostine capsules; avoid exposure to broken capsules. If dermal contact occurs, wash areas of skin contact immediately and thoroughly.
^ Mechanism Of Action
Lomustine alkylates DNA and RNA. As with other nitrosoureas, it may also inhibit several key enzymatic processes by carbamoylation of amino acids in proteins.