Plerixafor (Monograph)

Brand name: Mozobil
Drug class: Hematopoietic Agents
Chemical name: 1,1′,-[1,4-phenylenebis (methylene)]-bis-1,4,8,11-tetraacyclotetradecane
Molecular formula: C₂₈H₅₄N₈
CAS number: 110078-46-1

Introduction

CXCR4 chemokine-receptor antagonist; a hematopoietic stem cell mobilizer.

Uses for Plerixafor

Peripheral Blood Progenitor Cell Transplantation.

Used in combination with filgrastim (G-CSF) to mobilize hematopoietic stem cells into peripheral blood for collection (e.g., via leukapheresis as CD34⁺ peripheral blood progenitor cells [PBPCs]) and subsequent autologous transplantation in patients with non-Hodgkin’s lymphoma or multiple myeloma.

Plerixafor Dosage and Administration

Administration

Sub-Q Administration

Administer by sub-Q injection.

Administer plerixafor once daily in the evening, approximately 11 hours prior to a scheduled apheresis session.

Give concomitantly with filgrastim, with the initial daily dose of plerixafor beginning in the evening after the fourth daily morning dose of filgrastim. Administer filgrastim in the morning 4 days prior to the initial apheresis session and in the morning each day prior to apheresis.

Vials are for single use only; discard any unused portion.

Dosage

Adults

Peripheral Blood Progenitor Cell Transplantation

Sub-Q

0.24 mg/kg (based on actual body weight) daily (in the evening) for up to 4 consecutive days. Administer first dose only after the patient has received the initial 4 doses of filgrastim.

Dosage may be increased according to changes in weight, not to exceed 40 mg once daily. (See Absorption under Pharmacokinetics.)

Prescribing Limits

Adults

Peripheral Blood Progenitor Cell Transplantation

Sub-Q

Maximum 40 mg once daily.

Special Populations

Hepatic Impairment

No specific dosage recommendations at this time.

Renal Impairment

Peripheral Blood Progenitor Cell Transplantation

Sub-Q

Reduce dosage to 0.16 mg/kg daily (a 33% reduction in usual dosage) in patients with moderate to severe renal impairment (Cl_cr ≤50 mL/minute, as estimated from S_cr). Maximum dosage should not exceed 27 mg once daily.

Patients requiring hemodialysis: Insufficient experience to allow dosage recommendations.

Geriatric Patients

Select dosage with caution because of age-related decreases in renal function. However, no dosage adjustments required solely due to age. (See Renal Impairment under Dosage and Administration.)

Related/similar drugs

Abecma, Tecvayli, methotrexate, rituximab, cyclophosphamide, Revlimid, Rituxan

Cautions for Plerixafor

Contraindications

• No known contraindications.

Warnings/Precautions

Tumor Cell Mobilization

Possible mobilization of leukemic cells with subsequent contamination of the final apheresis product. Plerixafor is not recommended as part of a hematopoietic stem cell mobilization regimen in patients with leukemia.

Possible mobilization of tumor cells from the marrow into the peripheral circulation with unintentional collection into the apheresis product. Effect of potential reinfusion of tumor cells has not been well studied.

Hematologic Effects

Increase in peripheral leukocytes (e.g., increase in hematopoietic stem or CD34⁺ cells) with concomitant administration of plerixafor and filgrastim. Monitor total WBC count, including neutrophil count. If peripheral neutrophil count is >50,000 cells/mm³, use clinical judgment when considering administering plerixafor.

Thrombocytopenia reported. Monitor platelet counts in patients receiving plerixafor who then undergo subsequent apheresis.

Splenomegaly and Splenic Rupture

Splenomegaly (i.e., increased spleen weights), associated with extramedullary hematopoiesis, observed in animals receiving prolonged (2–4 weeks) therapy with higher than recommended doses (fourfold higher than recommended human doses). Effect of plerixafor on spleen size not established in humans. However, splenomegaly and splenic rupture reported in patients who received filgrastim (or pegfilgrastim) alone for the treatment of neutropenia or in conjunction with autologous stem cell transplantation.

Patients receiving plerixafor/filgrastim therapy who experience left upper abdominal pain and/or scapular or shoulder pain should be evaluated for splenic integrity (and possible rupture).

Fetal /Neonatal Morbidity and Mortality

May cause fetal harm; teratogenicity and embryolethality demonstrated in rats. Avoid pregnancy during therapy. If used during pregnancy or if patient becomes pregnant while receiving the drug, apprise of potential fetal hazard.

Specific Populations

Pregnancy

Category D. (See Fetal/Neonatal Morbidity and Mortality under Cautions.)

Lactation

Not known whether plerixafor is distributed into milk. Discontinue nursing or the drug, taking into the account the importance of the drug to the woman.

Pediatric Use

Safety and efficacy not established in pediatric patients <18 years of age.

Geriatric Use

No substantial differences in safety or efficacy relative to younger adults, but increased sensitivity cannot be ruled out.

Renal Impairment

Clearance may be decreased; dosage adjustments necessary in patients with moderate to severe renal impairment. (See Renal Impairment under Dosage and Administration.)

Common Adverse Effects

Diarrhea, nausea, injection site reactions, fatigue, headache, arthralgia, dizziness, vomiting, flatulence, insomnia.

Drug Interactions

Does not inhibit CYP isoenzymes 1A2, 2C9, 2C19, 2D6, 3A4, or 3A5 in vitro; does not induce CYP isoenzymes 1A2, 2B6, or 3A4; and is not a substrate of CYP isoenzymes. Pharmacokinetic interactions with drugs involving CYP isoenzymes unlikely.

Does not act as a substrate or inhibitor of P-glycoprotein in vitro.

Drugs that Reduce Renal Function

Potential pharmacokinetic interaction (increased plasma concentrations of plerixafor or concurrent drug).

Drugs that Compete for Renal Tubular Secretion

Potential pharmacokinetic interaction (increased plasma concentrations of plerixafor or concurrent drug).

Plerixafor Pharmacokinetics

Absorption

Bioavailability

Peak plasma concentrations occur approximately 30–60 minutes following sub-Q administration.

Systemic exposure increases as body weight increases.

Duration

Sustained increase in peripheral CD34⁺ counts observed 4–18 hours following sub-Q administration in healthy individuals receiving concomitant filgrastim; peak CD34⁺ counts observed 10–14 hours following sub-Q administration in such individuals.

Special Populations

In patients with mild (Cl_cr 51–80 mL/minute), moderate (31–50 mL/minute), and severe renal impairment (Cl_cr <31 mL/minute), mean AUC_{0–24 hr} is approximately 7%, 32%, and 39% higher, respectively, than in individuals with normal renal function.

Distribution

Extent

Not known whether plerixafor is distributed into milk.

Distributes mainly to extravascular fluid space.

Plasma Protein Binding

≤58%.

Elimination

Metabolism

Not metabolized (in vitro studies).

Elimination Route

Approximately 70% excreted unchanged in urine (healthy individuals).

Half-life

Terminal half-life is approximately 3–5 hours.

Special Populations

Renal impairment reduces clearance.

Stability

Storage

Parenteral

Solution

25°C (may be exposed to 15–30°C).

Actions

• Prevents the binding of stromal cell-derived factor-1α (SDF-1α) to the CXCR4 chemokine receptor.

• Disrupts interaction between SDF-1α and its receptor and interferes with retention of hematopoietic stem cells in bone marrow matrix.

• Subsequently, increased numbers of CD34⁺ hematopoietic progenitor cells are mobilized or released from bone marrow, resulting in peripheral leukocytosis.

• Mobilized CD34⁺ cells then collected by apheresis and used as stem-cell infusion to promote engraftment following high-dose chemotherapy associated with autologous stem-cell transplantation.

• No evidence of prolongation of QT interval or corrected QT interval, Bazett's formula_c (QT_c), with single doses ≤0.4 mg/kg.

Advice to Patients

• Importance of patient reporting symptoms of systemic reactions (e.g., urticaria, periorbital swelling, dyspnea, hypoxia) that may develop within 30 minutes following plerixafor administration.

• Importance of reporting symptoms of a vasovagal reaction, such as orthostatic hypotension or syncope, that develop during or shortly after (e.g., within 1 hour) plerixafor administration.

• Importance of informing clinician of itching, rash, or reaction at injection site. May treat such reactions with an OTC drug after consultation with healthcare provider.

• Risk of adverse GI effects (e.g., diarrhea, nausea, vomiting, flatulence, abdominal pain). Importance of advising patients how to manage GI effects and of reporting severe GI toxicity with plerixafor therapy.

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as concomitant illnesses.

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed; necessity for clinicians to advise women of childbearing potential to avoid pregnancy during therapy. If patient becomes pregnant during therapy with plerixafor, advise about risk to fetus.

• Importance of informing patients of other important precautionary information. (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Reload page with references included

Medical Disclaimer