Dosing and uses of Cytosar U, DepoCyt (cytarabine)
Adult dosage forms and strengths
injectable solution
- 10mg/mL
- 20mg/mL
- 100mg/mL
intrathecal injection, liposomal (DepoCyt)
- 50mg/5mL
powder for injection
- 100mg/vial
- 500mg/vial
- 1g/vial
- 2g/vial
Acute Nonlymphocytic Leukemia
IV administration for remission induction
- 100-200 mg/sq.meter/day for 5-10 days; begin second course in 2-4 weeks after initial therapy if necessary OR
- 100 mg/sq.meter for 7 days OR
- 100 mg/sq.meter/dose q12hr for 7 days
IT administration for remission induction
- 5-75 mg/sq.meter q2-7Days until CNS findings normalize
IV administration for remission maintenance
- 70-200 mg/sq.meter/day for 2-5 days at monthly intervals
IM administration for remission maintenance
- 1-1.5 mg/kg single dose for maintenance at 1- 4 week intervals
Meningeal Leukemia
IT administration
- 30 mg/sq.meter intrathecal (IT) q4Days until CSF findings normal plus one additional dose
Refractory Leukemia
IV administration
- 3 g/sq.meter IV (infusion over 1-3 hours) q12hr x 4-12 doses
- Repeat q2-3Weeks
Lymphomatous Meningitis (DepoCyt)
IT liposomal administration
- IT by intraventricular or lumbar puncture
- Induction: 50 mg q14Days weeks 1 and 3 (2 doses total)
- Consolidation: 50 mg q14Days (weeks 5, 7, 9) and an additional dose on week 13
- Maintenance: 50 mg q28Days for 4 doses (weeks 17, 21, 25, and 29)
Gliomas (Orphan)
IT liposomal (DepoCyt) received orphan designation for gliomas
Orphan indication sponsor
- Bruce Frankel, MD; Medical University of South Carolina, 96 Jonathan Lucas Street, Suite 428 CSB; Charleston, SC 29425
Administration
Allopurinol & IV hydration recommended for patients at risk of tumor lysis syndrome
IT: Patient should lie flat for 1 hour after lumbar puncture
Liposomal: To reduce incidence of arachnoiditis, administer dexamethasone concurrently
Monitor
CBC, LFTs, renal function
Suspend prescription if platelets <50,000/cu.mm or PMNs <1000/cu.mm
Other Indications & Uses
Conventional: ALL, AML, NHL
LiposomaL
Pediatric dosage forms and strengths
injectable solution
- 10mg/mL
- 20mg/mL
- 100mg/mL
powder for injection
- 100mg/vial
- 500mg/vial
- 1g/vial
- 2g/vial
Conventional
As in adults
Liposomal
Not recommended
Cytosar U, DepoCyt (cytarabine) adverse (side) effects
1-10%
Anorexia
Nausea
Vomiting
Diarrhea
Oral/anal inflammation
Thrombophlebitis
Bleeding
Myelosuppression
Rash
Fever
Hepatic dysfunction
Frequency not defined
Headache
Neuropathy
Chest pain
Pericarditis
Pneumonia
Anemia
Bleeding
Leukopenia
Thrombocytopenia
Kidney disease
Infectious disease
Sepsis
"Cytarabine syndrome": fever, myalgia, bone pain, rash, conjunctivitis, malaise
Skin ulcers
Cellulitis
Urinary retention
Neuritis
Jaundice
Anaphylaxis
Warnings
Black box warnings
Conventional formulation
- Only physicians experienced in cancer chemotherapy should administer
- For induction therapy, administer in facility with lab and supportive resources sufficient to monitor drug tolerance and protect and maintain patient if compromised by drug toxicity
- Main toxic effect is bone marrow suppression with leukopenia, thrombocytopenia, and anemia
- Less serious toxicity includes nausea, vomiting, diarrhea, abdominal pain, oral ulceration, and hepatic dysfunction
Arachnoiditis with liposomal IT administration
- In all clinical studies, chemical arachnoiditis, a syndrome manifested primarily by nausea, vomiting, headache and fever, was a common adverse event
- If left untreated, chemical arachnoiditis may be fatal
- The incidence and severity of chemical arachnoiditis can be reduced by coadministration of dexamethasone
Contraindications
Hypersensitivity
Liposomal cytarabine: active meningeal infection
Cautions
Potent bone marrow suppression
Severe and at times fatal CNS, GI, and pulmonoary toxicity
Cardiomyopathy with subsequent death reported following experimental high dose therapy with cytarabine in combination with cyclophosphamide when used for bone marrow transplant preparation
Do not use benzyl alcohol-containing solutions IT or in neonates
Avoid pregnancy
Liposomal IT administration
- CSF flow assessment should be considered before treatment is started Blockage to CSF flow may increase risk of neurotoxicity due to increased serum concentrations
- To reduce incidence of arachnoiditis, administer dexamethasone concurrently
- Hydrocephalus has also been reported, possibly precipitated by arachnoiditis
- Infectious meningitis may be associated with IT drug administration
- Following IT administration, CNS toxicity, including persistent extreme somnolence, hemiplegia, visual disturbances including blindness which may be total and permanent, deafness, cranial nerve palsies, and visual disturbances including blindness which may be total and permanent, have been reported
- Symptoms and signs of peripheral neuropathy (eg, pain, numbness, paresthesia, weakness, impaired bowel and bladder control) observed; in some cases, these signs and symptoms have been reported as Cauda Equina Syndrome
Pregnancy and lactation
Pregnancy category: d
Lactation: not known if excreted in breast milk, avoid
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Cytosar U, DepoCyt (cytarabine)
Mechanism of action
Metabolite cytarabine-5'-triphosphate inhibits DNA polymerase during S phase
Absorption
Systemic Exposure after IT: negligible
Peak Plasma Time: 20-60 min
Peak CSF Time (IT): 60 min
Peak CSF Concentration (IT): 30-50 mcg/mL
Distribution
Protein Bound: 13%
Metabolism
Metabolism: liver (major), kidneys (minor); neglible following IT administration
Metabolites: cytarabine-5'-triphosphate (ara-CTP)
Elimination
Half-Life: 1-3 hr
Half-Life (CSF after IT): 5.9-82.4 hr
CSF clearance rate: 0.24 mL/min
Excretion: urine
Administration
IV Incompatibilities
Additive: fluorouracil, gentamicin(?), heparin, hydrocortisone sodium succinate(?), insulin, methylprednisolone(?), nafcillin, oxacillin, penicillin G sodium
Y-site: allopurinol, amphotericin B cholesteryl SO4, ganciclovir
IV Compatibilities
Solution: compatible with most common IV fluids
Additive: corticotropin, daunorubicin/etoposide, hydroxyzine, lincomycin, methotrexate, mitoxantrone, ondansetron, KCl, NaHCO3, vincristine
Syringe: metoclopramide
Y-site: amifostine, amsacrine, aztreonam, cefepime, chlorpromazine, cimetidine, cladribine, dexamethasone, diphenhydramine, doxorubicin liposomal, droperidol, etoposide PO4, famotidine, filgrastim, fludarabine, furosemide, gatifloxacin, gemcitabine, gentamicin, granisetron, heparin, hydrocortisone, hydromorphone, idarubicin, linezolid, lorazepam, melphalan, methotrexate, methylprednisolone, metoclopramide, morphine SO4, ondansetron, paclitaxel, piperacillin/tazobactam, prochlorperazine, promethazine, propofol, ranitidine, sargramostim, Na Bicarb, teniposide, thiotepa, vinorelbine
IV Preparation
Reconstitute vials in BWI containing benzyl alcohol 0.945% as follows (CAUTION: Do not use benzyl alcohol for intrathecal inj)
100 mg vial: add 5 mL diluent to 20 mg/mL
500 mg vial: add 10 mL diluent to 50 mg/mL
1 g vial: add 10 mL diluent to 100 mg/mL
2 g vial: add 20 mL diluent to 100 mg/mL
IV Administration
Rapid IV, infusion over 1-3 hr, or SC intrathecaL
Has been administered by IM & continuous SC infusion
Storage
Store intact vials at controlled room temp
