Cytarabine STADA

What Is Cytarabine STADA and What Is It Used For?

Cytarabine, also known as cytosine arabinoside or Ara-C, is one of the most extensively studied and widely used antineoplastic agents in hematologic oncology. First synthesized in the early 1960s from compounds originally isolated from the Caribbean sponge Tectitethya crypta, cytarabine has become a foundational drug in the treatment of acute leukemias. Cytarabine STADA is a branded generic formulation manufactured by STADA Arzneimittel AG, supplied as a ready-to-use 50 mg/ml solution for infusion.

The drug belongs to the antimetabolite class of cytotoxic agents, specifically the pyrimidine analogue subgroup. Antimetabolites mimic the structure of natural metabolites required for DNA and RNA synthesis, thereby disrupting normal cellular replication. Cytarabine is structurally similar to deoxycytidine, one of the four building blocks of DNA, but contains an arabinose sugar instead of deoxyribose. This subtle structural difference allows it to interfere with DNA replication once incorporated into the growing DNA strand.

After entering the cell, cytarabine must be phosphorylated to its active triphosphate form, cytarabine triphosphate (Ara-CTP), through a series of enzymatic steps. Ara-CTP then competes with the natural substrate deoxycytidine triphosphate (dCTP) for incorporation into DNA by DNA polymerase alpha. Once incorporated, it causes premature chain termination and inhibits further DNA elongation. Additionally, cytarabine inhibits DNA polymerase and DNA repair enzymes, further contributing to its cytotoxic effect. The drug is most active during the S-phase (DNA synthesis phase) of the cell cycle, making it particularly effective against rapidly proliferating cells such as leukemic blasts.

Cytarabine is used in the treatment of several hematologic malignancies. Its primary indications include:

• Acute myeloid leukemia (AML): Cytarabine is the backbone of both induction therapy (often combined with an anthracycline such as daunorubicin in the "7+3" regimen) and high-dose consolidation therapy. It remains the single most important drug in AML treatment according to NCCN and ESMO guidelines.
• Acute lymphoblastic leukemia (ALL): Used as part of multi-agent chemotherapy protocols for both induction and consolidation phases in pediatric and adult ALL.
• Chronic myeloid leukemia (CML): Employed during blast crisis or accelerated phase when the disease transforms into an acute leukemia-like state.
• Non-Hodgkin lymphoma (NHL): Used in salvage chemotherapy regimens such as DHAP (dexamethasone, high-dose cytarabine, cisplatin) for relapsed or refractory aggressive lymphomas.
• Meningeal leukemia or lymphoma: Administered intrathecally (directly into the cerebrospinal fluid) for treatment or prophylaxis of central nervous system involvement.

Cytarabine is listed on the World Health Organization (WHO) Model List of Essential Medicines, underscoring its critical importance in cancer treatment worldwide. The European Medicines Agency (EMA) has approved cytarabine-containing products across all EU member states, and the drug is available in numerous generic formulations globally. Despite being over 60 years old, cytarabine has not been superseded by newer agents for its core indications and remains indispensable in modern hematologic oncology.

What Should You Know Before Taking Cytarabine STADA?

Before initiating treatment with Cytarabine STADA, your oncologist will conduct a thorough evaluation of your overall health, organ function, and disease status. Cytarabine is a potent cytotoxic agent with significant toxicity, and careful patient selection and monitoring are essential to maximize therapeutic benefit while minimizing risk. The following sections detail the most important considerations before starting therapy.

Contraindications

Cytarabine STADA must not be used in the following situations:

• Hypersensitivity: Known allergy to cytarabine or any of the excipients in the formulation. Anaphylactic reactions, though rare, have been reported.
• Severe pre-existing myelosuppression: Patients with critically low blood counts not caused by the malignancy being treated should not receive cytarabine until marrow recovery, unless the potential benefit clearly outweighs the risk.
• Active, uncontrolled infections: Because cytarabine causes profound immunosuppression, active systemic infections should be treated and controlled before initiating chemotherapy.

Warnings and Precautions

Several important precautions apply to cytarabine treatment:

• Bone marrow suppression: This is the most significant and expected toxicity. Leukopenia, thrombocytopenia, and anemia are dose-dependent and inevitable at therapeutic doses. Nadir blood counts typically occur 7-14 days after administration, with recovery by days 21-28. Complete blood counts must be monitored daily during induction therapy.
• Hepatotoxicity: Cytarabine can cause liver toxicity, particularly at high doses. Liver function tests (ALT, AST, bilirubin, alkaline phosphatase) should be monitored regularly. Dose adjustments may be necessary in patients with pre-existing liver impairment.
• Neurotoxicity: High-dose cytarabine (typically ≥2 g/m² per dose) carries a significant risk of cerebellar toxicity, manifesting as ataxia (difficulty with balance and coordination), dysarthria (slurred speech), and nystagmus (involuntary eye movements). The risk is increased in patients over 60 years of age and those with renal impairment. Neurological function should be assessed before each high-dose cycle.
• Cytarabine syndrome: A characteristic syndrome consisting of fever, myalgia, bone pain, maculopapular rash, conjunctivitis, and malaise may occur 6-12 hours after administration. Corticosteroids are effective for prevention and treatment.
• Tumor lysis syndrome: Rapid destruction of leukemia cells can lead to metabolic complications including hyperuricemia, hyperkalemia, hyperphosphatemia, and hypocalcemia. Adequate hydration and urate-lowering therapy (e.g., allopurinol or rasburicase) should be initiated before treatment.
• Immunosuppression: Cytarabine causes profound immunosuppression. Live vaccines must not be administered during treatment. Patients should be monitored closely for signs of infection, and prophylactic antimicrobials may be warranted.
• Renal impairment: Cytarabine and its metabolites are renally excreted. Dose adjustments may be necessary in patients with significant renal dysfunction, particularly for high-dose regimens.

Pregnancy and Breastfeeding

Cytarabine is classified as teratogenic based on animal studies and case reports in humans. The drug has been associated with limb and ear malformations when administered during the first trimester of pregnancy. Use during pregnancy is contraindicated unless the clinical situation is life-threatening and no safer alternative exists. The following precautions apply:

• Women of childbearing potential must use effective contraception during treatment and for at least 6 months after the last dose of cytarabine.
• Male patients should use effective contraception during treatment and for at least 3 months after the last dose, as cytarabine may damage sperm DNA.
• Breastfeeding must be discontinued during treatment with cytarabine, as it is unknown whether the drug passes into breast milk. Breastfeeding should not be resumed for at least 2 weeks after the final dose.
• Fertility: Both men and women should be counseled about the potential impact on fertility. Sperm banking and oocyte cryopreservation should be discussed before treatment initiation.

How Does Cytarabine STADA Interact with Other Drugs?

Drug interactions with cytarabine are clinically significant and must be carefully managed. Because cytarabine is almost always administered as part of multi-agent chemotherapy protocols, potential interactions between the component drugs have been extensively studied. The following table summarizes the most important known interactions.

Major Interactions

The most clinically significant interactions involve drugs that either have their absorption impaired by cytarabine-induced gastrointestinal mucosal damage (such as oral digoxin) or where the timing of administration relative to other antimetabolites critically affects efficacy and toxicity. The interaction with methotrexate is particularly important in clinical practice, as both drugs are frequently used in combination protocols for ALL. Studies have demonstrated that cytarabine administered 24 hours after methotrexate enhances the formation of Ara-CTP (the active intracellular metabolite), while the reverse sequence may reduce efficacy.

The contraindication of live vaccines during cytarabine therapy extends for at least 3 months after the completion of chemotherapy or until immune recovery has been confirmed. Household contacts of patients receiving cytarabine should also avoid oral polio vaccine but can safely receive other live vaccines.

Minor Interactions

Several additional interactions of lesser clinical significance have been reported. Cytarabine may transiently alter the plasma levels of other drugs metabolized by hepatic enzymes due to its hepatotoxic effects. Patients receiving anticoagulant therapy with warfarin may experience fluctuations in INR during cytarabine treatment due to altered vitamin K absorption and hepatic function changes. Close monitoring of coagulation parameters is advisable. Additionally, cytarabine has been reported to reduce the bioavailability of oral iron supplements due to gastrointestinal mucosal damage.

What Is the Correct Dosage of Cytarabine STADA?

Cytarabine dosing is complex and varies significantly based on the disease being treated, the specific protocol, the patient's body surface area, organ function, and age. The following information provides general guidance, but all cytarabine doses must be calculated and verified by the prescribing oncologist. Cytarabine STADA 50 mg/ml solution can be diluted in sodium chloride 0.9% or glucose 5% for intravenous infusion.

Adults

For adult patients with AML, the most established induction regimen is the "7+3" protocol, where cytarabine is administered as a continuous intravenous infusion at 100-200 mg/m²/day for 7 consecutive days, combined with an anthracycline (typically daunorubicin 60 mg/m²/day or idarubicin 12 mg/m²/day) for the first 3 days. This regimen achieves complete remission in 60-80% of patients under 60 years of age.

High-dose cytarabine (HiDAC) consolidation therapy, using doses of 1-3 g/m² administered intravenously over 1-3 hours every 12 hours for 6 doses (days 1, 3, and 5), has been shown to significantly improve long-term survival in patients with favorable and intermediate-risk AML cytogenetics. The landmark Cancer and Leukemia Group B (CALGB) 8525 trial demonstrated a significant survival advantage for patients receiving 3 g/m² compared with lower doses in consolidation.

For subcutaneous administration in maintenance or low-intensity protocols, cytarabine is typically given at 10-20 mg/m² once or twice daily for 7 to 14 consecutive days. This route avoids the need for continuous intravenous access and can sometimes be administered in an outpatient setting under appropriate supervision.

Children

Pediatric dosing of cytarabine is generally based on body surface area and follows specific pediatric oncology protocols such as those developed by the Children's Oncology Group (COG) or the BFM (Berlin-Frankfurt-Munster) group. Standard induction doses in pediatric AML are similar to adult dosing (100-200 mg/m²/day for 7-10 days). For intrathecal administration in children, doses are age-adjusted rather than based on body surface area: typically 30 mg for children aged 1-2 years, 50 mg for children aged 2-3 years, and 70 mg for children over 3 years of age.

Children generally tolerate cytarabine better than adults, with lower rates of cerebellar toxicity during high-dose therapy. However, they remain at significant risk for myelosuppression and its complications, and close hematologic monitoring is equally important in the pediatric population.

Elderly

Elderly patients (typically defined as those over 60-65 years of age) present unique challenges in cytarabine therapy. Age-related decline in renal and hepatic function, reduced bone marrow reserve, and higher rates of comorbidities increase the risk of severe toxicity. Key considerations include:

• Induction therapy: Standard 7+3 induction remains appropriate for fit elderly patients, but treatment-related mortality is higher (10-20% compared with 5% in younger patients). Reduced-intensity regimens or hypomethylating agents (azacitidine, decitabine) may be preferred for unfit patients.
• High-dose consolidation: Doses above 1.5 g/m² are generally not recommended in patients over 60 years due to significantly increased risk of fatal cerebellar toxicity. The CALGB study demonstrated no survival benefit for high-dose consolidation in patients over 60.
• Neurotoxicity monitoring: Cerebellar function should be formally assessed before each high-dose cycle using tests of coordination, balance, and speech. Any signs of cerebellar dysfunction mandate immediate discontinuation.

Missed Dose

Cytarabine is administered in a hospital setting under physician supervision, so missed doses are unlikely to occur in practice. However, if a scheduled dose is delayed or missed due to medical reasons (e.g., unresolved infection, inadequate blood count recovery), the treating oncologist will assess whether the dose should be given at a later time, whether the treatment cycle should be extended, or whether the next cycle should be delayed. Patients should never attempt to make up for a missed dose without explicit instruction from their oncologist.

Overdose

There is no specific antidote for cytarabine overdose. Treatment is supportive and focused on managing the expected consequences of excessive myelosuppression. Overdose symptoms may include severe pancytopenia, overwhelming infections, gastrointestinal hemorrhage, and at very high doses, potentially fatal neurotoxicity including coma. In the event of accidental overdose, immediate measures include:

• Aggressive supportive care including broad-spectrum antibiotics, antifungal prophylaxis, and blood product transfusions
• Growth factor support (G-CSF) may help accelerate neutrophil recovery
• Neurological monitoring if high doses were inadvertently administered
• Cytarabine is not effectively removed by hemodialysis

What Are the Side Effects of Cytarabine STADA?

As a cytotoxic chemotherapy agent, cytarabine affects both cancer cells and normal rapidly dividing cells, leading to a predictable pattern of adverse effects. The severity of side effects is dose-dependent, with high-dose regimens carrying substantially greater risks than standard-dose therapy. Understanding the expected side effects and their management is crucial for patients and caregivers. The following frequency grid categorizes the known side effects by how commonly they occur.

The bone marrow suppression caused by cytarabine follows a predictable pattern. After standard-dose induction therapy, the white blood cell count typically begins to fall within 24-48 hours, reaching its nadir (lowest point) at approximately days 7-14. Platelet counts follow a similar pattern, with nadir around days 12-14. Recovery generally begins by days 21-28, although this timeline can vary. During the nadir period, patients are at highest risk for life-threatening infections and bleeding complications, requiring vigilant monitoring in a hospital setting.

High-dose cytarabine therapy (≥2 g/m²) introduces additional serious toxicities not typically seen at standard doses. Cerebellar toxicity is the most concerning, occurring in approximately 10-25% of patients receiving high-dose Ara-C, with risk factors including age over 60, renal impairment, and cumulative dose. This toxicity may be irreversible in some cases. Prophylactic corticosteroid eye drops are routinely administered during high-dose cytarabine to prevent hemorrhagic conjunctivitis, which occurs in up to 80% of patients without prophylaxis.

Gastrointestinal toxicity is common across all dose levels and can range from mild nausea to severe necrotizing colitis (typhlitis), a potentially life-threatening condition affecting the cecum and ascending colon. Anti-emetic prophylaxis with 5-HT3 receptor antagonists (such as ondansetron) is standard practice during cytarabine administration. Adequate oral care and mouth hygiene are essential to minimize the severity of stomatitis.

How Should You Store Cytarabine STADA?

Proper storage of cytarabine is essential to maintain its chemical stability, sterility, and therapeutic potency. As a cytotoxic agent, special precautions apply to both storage and disposal. Cytarabine STADA 50 mg/ml solution for infusion should be stored according to the following guidelines:

• Temperature: Store below 25°C (77°F) at room temperature. Brief exposure to temperatures up to 30°C during transport is acceptable but should be minimized.
• Light protection: Keep vials in the original carton to protect from light. Cytarabine is photosensitive and prolonged light exposure may lead to degradation.
• Freezing: Do not freeze. If the solution has been frozen, it should not be used.
• Visual inspection: Before use, visually inspect the solution for particulate matter and discoloration. The solution should be clear and colorless to slightly yellowish. Do not use if particles are visible or the solution is discolored.
• After dilution: Once diluted for infusion in sodium chloride 0.9% or glucose 5%, the solution should be used within 24 hours when stored at 2-8°C, or within 8 hours at room temperature, unless microbiological safety can be assured.
• Disposal: Unused cytarabine and all materials that have come into contact with the drug must be disposed of according to local cytotoxic waste regulations. Do not dispose of through household waste or wastewater.

Healthcare professionals handling cytarabine must follow institutional guidelines for safe handling of cytotoxic agents, including the use of protective gloves, gowns, and preparation in a certified biological safety cabinet. In the event of accidental skin contact, wash the affected area immediately with soap and water. If eye contact occurs, irrigate thoroughly with water and seek medical attention.

What Does Cytarabine STADA Contain?

Cytarabine STADA is formulated as a preservative-free, sterile solution for injection and infusion. Understanding the composition is important for identifying potential incompatibilities and for patients with known sensitivities to specific excipients.

The molecular formula of cytarabine is C₉H₁₃N₃O₅, with a molecular weight of 243.22 g/mol. Chemically, it is 4-amino-1-β-D-arabinofuranosyl-2(1H)-pyrimidinone. The drug is structurally related to the natural nucleoside deoxycytidine but differs in the configuration of the sugar moiety (arabinose vs. deoxyribose), which is responsible for its cytotoxic activity through disruption of DNA synthesis.

Cytarabine STADA is available in vials containing various total volumes depending on the strength. The solution has a pH between 7.0 and 9.0 and is compatible with sodium chloride 0.9% injection and glucose 5% injection for dilution prior to intravenous infusion. It should not be mixed with other drugs in the same infusion bag unless compatibility has been established. Known incompatibilities include heparin, insulin, and fluorouracil when mixed directly in the same solution.