Included as part of the PRECAUTIONS section.

Tumor Cell Mobilization in Leukemia Patients

For the purpose of HSC mobilization, Mozobil (plerixafor injection) may cause mobilization of leukemic cells and subsequent contamination of the apheresis product. Therefore, Mozobil (plerixafor injection) is not intended for HSC mobilization and harvest in patients with leukemia.

Hematologic Effects

Leukocytosis

Administration of Mozobil (plerixafor injection) in conjunction with G-CSF increases circulating leukocytes as well as HSC populations. Monitor white blood cell counts during Mozobil (plerixafor injection) use. Exercise clinical judgment when administering Mozobil (plerixafor injection) to patients with peripheral blood neutrophil counts above 50,000/mcL.

Thrombocytopenia

Thrombocytopenia has been observed in patients receiving Mozobil (plerixafor injection) . Monitor platelet counts in all patients who receive Mozobil (plerixafor injection) and then undergo apheresis.

Potential for Tumor Cell Mobilization

When Mozobil (plerixafor injection) is used in combination with G-CSF for HSC mobilization, tumor cells may be released from the marrow and subsequently collected in the leukapheresis product. The effect of potential reinfusion of tumor cells has not been well-studied.

Splenic Enlargement and Potential for Rupture

Higher absolute and relative spleen weights associated with extramedullary hematopoiesis were observed following prolonged (2 to 4 weeks) daily plerixafor SC administration in rats at doses approximately 4-fold higher than the recommended human dose based on body surface area. The effect of Mozobil (plerixafor injection) on spleen size in patients was not specifically evaluated in clinical studies. Evaluate individuals receiving Mozobil (plerixafor injection) in combination with G-CSF who report left upper abdominal pain and/or scapular or shoulder pain for splenic integrity.

Pregnancy

Pregnancy Category D

Mozobil (plerixafor injection) may cause fetal harm when administered to a pregnant woman. Plerixafor was teratogenic in animals. There are no adequate and well-controlled studies in pregnant women using Mozobil (plerixafor injection) . Women of childbearing potential should be advised to avoid becoming pregnant while receiving treatment with Mozobil (plerixafor injection) . If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus. [see Use In Specific Populations]

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity studies with plerixafor have not been conducted.

Plerixafor was not genotoxic in an in vitro bacterial mutation assay (Ames test in Salmonella), an in vitro chromosomal aberration test using V79 Chinese hamster cells, or an in vivo bone marrow micronucleus test in rats after subcutaneous doses up to 25 mg/kg (150mg/m²).

The effect of plerixafor on human fertility is unknown. The effect of plerixafor on male or female fertility was not studied in designated reproductive toxicology studies. The staging of spermatogenesis measured in a 28-day repeated dose toxicity study in rats revealed no abnormalities considered to be related to plerixafor. No histopathological evidence of toxicity to male or female reproductive organs was observed in 28-day repeated dose toxicity studies.

Use In Specific Populations

Pregnancy

Pregnancy Category D

Plerixafor was teratogenic in animals. Plerixafor administered to pregnant rats induced embryo-fetal toxicities including fetal death, increased resorptions and post-implantation loss, decreased fetal weights, anophthalmia, shortened digits, cardiac interventricular septal defect, ringed aorta, globular heart, hydrocephaly, dilatation of olfactory ventricles, and retarded skeletal development. Embryo-fetal toxicities occurred mainly at a dose of 90 mg/m² (approximately 10 times the recommended human dose of 0.24 mg/kg when compared on a mg/m² basis or 10 times the AUC in subjects with normal renal function who received a single dose of 0.24 mg/kg).

Nursing Mothers

It is not known whether plerixafor is excreted in human milk. Because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants from Mozobil (plerixafor injection) , a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

The safety and efficacy of Mozobil (plerixafor injection) in pediatric patients have not been established in controlled clinical studies.

Geriatric Use

Of the total number of subjects in controlled clinical studies of Mozobil (plerixafor injection) , 24% were 65 and over, while 0.8% were 75 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

Since plerixafor is mainly excreted by the kidney, no dose modifications are necessary in elderly individuals with normal renal function. In general, care should be taken in dose selection for elderly patients due to the greater frequency of decreased renal function with advanced age. Dosage adjustment in elderly patients with CLcr ≤ 50 mL/min is recommended. [see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY]

Renal Impairment

In patients with moderate and severe renal impairment (CLCr ≤ 50 mL/min), reduce the dose of plerixafor by one-third to 0.16 mg/kg. [see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY]

Last reviewed on RxList: 7/13/2010
This monograph has been modified to include the generic and brand name in many instances.