Comparative Pharmacology
Head-to-head clinical analysis: ARZERRA versus DEPOCYT.
Head-to-head clinical analysis: ARZERRA versus DEPOCYT.
ARZERRA vs DEPOCYT
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Ofatumumab is a fully human monoclonal antibody that binds specifically to the CD20 molecule on B lymphocytes, resulting in complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) of CD20+ cells.
Cytarabine is a nucleoside analog that inhibits DNA polymerase, leading to termination of DNA chain elongation and cell death in the S phase of the cell cycle.
ARZERRA (ofatumumab) for chronic lymphocytic leukemia (CLL): Initial dose 300 mg IV, then 1 week later 2000 mg IV weekly for 6 doses, then 2000 mg IV every 4 weeks for up to 4 additional doses. For relapsed CLL: 300 mg IV followed by 1000 mg IV on day 8, then 1000 mg IV on day 15 and day 22 of cycle 1, then 1000 mg IV on day 1 of cycles 2-6 (28-day cycles). Premedicate with acetaminophen, antihistamine, and corticosteroid.
50 mg intrathecally via lumbar puncture or intraventricularly via Ommaya reservoir on days 1, 15, 29, 43, 57, 71, 85, and 99 for induction; followed by consolidation and maintenance doses. Administer with dexamethasone 4 mg PO/IV twice daily for 5 days starting on the day of DepoCyt injection.
None Documented
None Documented
Mean terminal elimination half-life after first dose is approximately 14 days (range 7–21 days) and increases with repeated dosing due to target-mediated clearance saturation; at steady state, half-life is ~24 days.
After intrathecal administration, the terminal half-life of cytarabine in CSF is 2.5-4.5 hours (mean 3.5 hours) due to slow clearance from CSF; systemic half-life is 10-15 minutes due to rapid deamination.
Arzerra (ofatumumab) is eliminated primarily via the reticuloendothelial system and catabolism; renal excretion is minimal (<1% of dose as intact antibody). Biliary/fecal excretion has not been characterized, but as a monoclonal antibody, it is not significantly excreted in urine or feces.
Renal excretion of cytarabine metabolites accounts for >70% of elimination; unchanged cytarabine excretion is minimal (<10%). Biliary/fecal excretion is negligible (<5%).
Category C
Category C
Antineoplastic, Monoclonal Antibody
Antineoplastic