(filgrastim-aafi)

Prescribing Information
Download Prescribing Information

12 CLINICAL PHARMACOLOGY

12 CLINICAL PHARMACOLOGY

12.1 Mechanism of Action

Colony-stimulating factors are glycoproteins which act on hematopoietic cells by binding to specific cell surface receptors and stimulating proliferation‚ differentiation commitment‚ and some end-cell functional activation.

Endogenous G-CSF is a lineage-specific colony-stimulating factor that is produced by monocytes‚ fibroblasts, and endothelial cells. G-CSF regulates the production of neutrophils within the bone marrow and affects neutrophil progenitor proliferation‚ differentiation, and selected end-cell functions (including enhanced phagocytic ability‚ priming of the cellular metabolism associated with respiratory burst‚ antibody-dependent killing, and the increased expression of some cell surface antigens). G-CSF is not species-specific and has been shown to have minimal direct in vivo or in vitro effects on the production or activity of hematopoietic cell types other than the neutrophil lineage.

12.2 Pharmacodynamics

In phase 1 studies involving 96 patients with various non-myeloid malignancies‚ filgrastim administration resulted in a dose-dependent increase in circulating neutrophil counts over the dose range of 1 to 70 mcg/kg/day. This increase in neutrophil counts was observed whether filgrastim was administered intravenous (1 to 70 mcg/kg twice daily)‚ subcutaneous (1 to 3 mcg/kg once daily)‚ or by continuous subcutaneous infusion (3 to 11 mcg/kg/day). With discontinuation of filgrastim therapy‚ neutrophil counts returned to baseline in most cases within 4 days. Isolated neutrophils displayed normal phagocytic (measured by zymosan-stimulated chemoluminescence) and chemotactic (measured by migration under agarose using N-formyl-methionyl-leucyl-phenylalanine [fMLP] as the chemotaxin) activity in vitro.

The absolute monocyte count was reported to increase in a dose-dependent manner in most patients receiving filgrastim; however‚ the percentage of monocytes in the differential count remained within the normal range. Absolute counts of both eosinophils and basophils did not change and were within the normal range following administration of filgrastim. Increases in lymphocyte counts following filgrastim administration have been reported in some normal subjects and patients with cancer.

White blood cell (WBC) differentials obtained during clinical trials have demonstrated a shift towards earlier granulocyte progenitor cells (left shift)‚ including the appearance of promyelocytes and myeloblasts‚ usually during neutrophil recovery following the chemotherapy-induced nadir. In addition‚ Dohle bodies‚ increased granulocyte granulation‚ and hypersegmented neutrophils have been observed. Such changes were transient and were not associated with clinical sequelae, nor were they necessarily associated with infection.

12.3 Pharmacokinetics

Filgrastim products exhibit nonlinear pharmacokinetics. Clearance is dependent on filgrastim product concentration and neutrophil count: G-CSF receptor-mediated clearance is saturated by high concentration of filgrastim products and is diminished by neutropenia. In addition, filgrastim products are cleared by the kidney.

Subcutaneous administration of 3.45 mcg/kg and 11.5 mcg/kg of filgrastim resulted in maximum serum concentrations of 4 and 49 ng/mL‚ respectively‚ within 2 to 8 hours. After intravenous administration, the volume of distribution averaged 150 mL/kg and the elimination half-life was approximately 3.5 hours in both normal subjects and cancer subjects. Clearance rates of filgrastim were approximately 0.5 to 0.7 mL/minute/kg. Single parenteral doses or daily intravenous doses‚ over a 14-day period‚ resulted in comparable half-lives. The half-lives were similar for intravenous administration (231 minutes‚ following doses of 34.5 mcg/kg) and for subcutaneous administration (210 minutes‚ following filgrastim dosages of 3.45 mcg/kg). Continuous 24-hour intravenous infusions of 20 mcg/kg over an 11 to 20-day period produced steady-state serum concentrations of filgrastim with no evidence of drug accumulation over the time period investigated. The absolute bioavailability of filgrastim after subcutaneous administration is 60% to 70%.

Specific Populations

Pediatric Patients

The pharmacokinetics of filgrastim in pediatric patients after chemotherapy are similar to those in adult patients receiving the same weight-normalized doses, suggesting no age-related differences in the pharmacokinetics of filgrastim products [see Use in Specific Populations (8.4)].

Renal Impairment

In a study with healthy volunteers, subjects with moderate renal impairment, and subjects with end-stage renal disease (n = 4 per group), higher serum concentrations were observed in subjects with end-stage renal disease. However, dose adjustment in patients with renal impairment is not necessary.

Hepatic Impairment

Pharmacokinetics and pharmacodynamics of filgrastim are similar between subjects with hepatic impairment and healthy subjects (n = 12/group). The study included 10 subjects with mild hepatic impairment (Child-Pugh Class A) and 2 subjects with moderate hepatic impairment (Child-Pugh Class B). Therefore, NIVESTYM dose adjustment for patients with hepatic impairment is not necessary.

12.6 Immunogenicity

The observed incidence of anti-drug antibodies is highly dependent on the sensitivity and specificity of the assay. Differences in assay methods preclude meaningful comparisons of the incidence of anti-drug antibodies in the studies described below with the incidence of anti-drug antibodies in other studies, including those of filgrastim or of other filgrastim products.

While available data suggest that a small proportion of patients developed binding antibodies to filgrastim products, the nature and specificity of these antibodies has not been adequately studied. In clinical studies using filgrastim, the incidence of antibodies binding to filgrastim was 3% (11/333). In these 11 patients, no evidence of a neutralizing response was observed using a cell-based bioassay. Because of the low occurrence of anti-drug antibodies, the effect of these antibodies on the pharmacokinetics, pharmacodynamics, safety, and/or effectiveness of filgrastim products is unknown.

Cytopenias resulting from an antibody response to exogenous growth factors have been reported on rare occasions in patients treated with other recombinant growth factors.

Medication Guide

MEDICATION GUIDE

Patient Information
NIVESTYM (Neye-ves-tim)
(filgrastim-aafi)
injection

What is NIVESTYM?

NIVESTYM is a man-made form of granulocyte colony-stimulating factor (G-CSF). G-CSF is a substance produced by the body. It stimulates the growth of neutrophils, a type of white blood cell important in the body's fight against infection.

Do not take NIVESTYM if you have had a serious allergic reaction to human G-CSFs such as filgrastim products or pegfilgrastim products.

Before you take NIVESTYM, tell your healthcare provider about all of your medical conditions, including if you:

•
have a sickle cell disorder.
•
have kidney problems.
•
are receiving radiation therapy.
•
are pregnant or plan to become pregnant. It is not known if NIVESTYM will harm your unborn baby.
•
are breastfeeding or plan to breastfeed. It is not known if NIVESTYM passes into your breast milk.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

How will I receive NIVESTYM?

•
NIVESTYM injections can be given by a healthcare provider by intravenous (IV) infusion or under your skin (subcutaneous injection). Your healthcare provider may decide subcutaneous injections can be given at home by you or your caregiver. If NIVESTYM is given at home, see the detailed "Instructions for Use" that comes with your NIVESTYM for information on how to prepare and inject a dose of NIVESTYM.
•
You and your caregiver should be shown how to prepare and inject NIVESTYM before you use it, by your healthcare provider.
•
You should not try to inject a dose of NIVESTYM less than 0.3 mL (180 mcg) from a NIVESTYM prefilled syringe. A dose less than 0.3 mL cannot be accurately measured using the NIVESTYM prefilled syringe.
•
Your healthcare provider will tell you how much NIVESTYM to inject and when to inject it. Do not change your dose or stop NIVESTYM unless your healthcare provider tells you to.
•
If you are receiving NIVESTYM because you are also receiving chemotherapy, your dose of NIVESTYM should be injected at least 24 hours before or 24 hours after your dose of chemotherapy. Your healthcare provider will do blood tests to monitor your white blood cell count, and if necessary, adjust your NIVESTYM dose.
•
If you miss a dose of NIVESTYM, talk to your healthcare provider about when you should give your next dose.

What are the possible side effects of NIVESTYM?

NIVESTYM may cause serious side effects, including:

•
Spleen rupture. Your spleen may become enlarged and can rupture. A ruptured spleen can cause death. Call your healthcare provider right away if you have pain in the left upper stomach (abdomen) area or your left shoulder.
•
A serious lung problem called acute respiratory distress syndrome (ARDS). Call your healthcare provider or get emergency medical help right away if you have shortness of breath with or without a fever, trouble breathing, or a fast rate of breathing.
•
Serious allergic reactions. NIVESTYM can cause serious allergic reactions. These reactions can cause a rash over your whole body, shortness of breath, wheezing, dizziness, swelling around your mouth or eyes, fast heart rate, and sweating. If you have any of these symptoms, stop using NIVESTYM and call your healthcare provider or get emergency medical help right away.
•
Sickle cell crises. You may have a serious sickle cell crisis, which could lead to death, if you have a sickle cell disorder and receive NIVESTYM. Call your healthcare provider right away if you have symptoms of sickle cell crisis such as pain or difficulty breathing.
•
Kidney injury (glomerulonephritis). NIVESTYM can cause kidney injury. Call your healthcare provider right away if you develop any of the following symptoms:
o
swelling of your face or ankles
o
blood in your urine or dark colored urine
o
you urinate less than usual
•
Capillary leak syndrome. NIVESTYM can cause fluid to leak from blood vessels into your body's tissues. This condition is called "Capillary Leak Syndrome" (CLS). CLS can quickly cause you to have symptoms that may become life-threatening. Get emergency medical help right away if you develop any of the following symptoms:
o
swelling or puffiness and are urinating less than usual
o
trouble breathing
o
swelling of your stomach area (abdomen) and feeling of fullness
o
dizziness or feeling faint
o
a general feeling of tiredness
•
Myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML).
o
NIVESTYM may increase the risk of developing a precancerous condition called MDS or a type of blood cancer called AML in people who were born with low white blood cell counts (congenital neutropenia).
o
If you have breast cancer or lung cancer, when NIVESTYM is used with chemotherapy and radiation therapy, or with radiation therapy only, you may have an increased risk of developing MDS or AML.
o
Symptoms of MDS and AML may include tiredness, fever, and easy bruising or bleeding.
o
Call your healthcare provider if you develop any of these symptoms during treatment with NIVESTYM.
•
Decreased platelet count (thrombocytopenia). Your healthcare provider will check your blood during treatment with NIVESTYM. Tell your healthcare provider if you have unusual bleeding or bruising during treatment with NIVESTYM. This could be a sign of decreased platelet counts, which may reduce the ability of your blood to clot.
•
Increased white blood cell count (leukocytosis). Your healthcare provider will check your blood during treatment with NIVESTYM.
•
Inflammation of your blood vessels (cutaneous vasculitis). Tell your healthcare provider right away if you develop purple spots or redness of your skin.
•
Inflammation of the aorta (aortitis). Inflammation of the aorta (the large blood vessel which transports blood from the heart to the body) has been reported in patients who received NIVESTYM. Symptoms may include fever, abdominal pain, feeling tired, and back pain. Call your healthcare provider if you experience these symptoms.

The most common side effects experienced in patients receiving NIVESTYM include:

•
Patients with cancer receiving chemotherapy: fever, pain, rash, cough, and shortness of breath
•
Patients with acute myeloid leukemia receiving chemotherapy: pain, nose bleed, and rash
•
Patients with cancer receiving chemotherapy followed by bone marrow transplant: rash
•
Patients who are having their own blood cells collected: bone pain, fever, and headache
•
Patients with severe chronic neutropenia: pain, decreased red blood cells, nose bleed, diarrhea, reduced sensation, and hair loss

These are not all the possible side effects of NIVESTYM. Call your healthcare provider for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store NIVESTYM?

•
Store NIVESTYM in the refrigerator between 36°F to 46°F (2°C to 8°C).
•
Do not freeze.
•
Keep NIVESTYM in the original carton to protect from light or physical damage. Do not leave NIVESTYM in direct sunlight.
•
Do not shake NIVESTYM.
•
Take NIVESTYM out of the refrigerator 30 minutes before use and allow it to reach room temperature before preparing an injection.
•
Throw away (dispose of) any NIVESTYM that has been left at room temperature for longer than 24 hours.
•
After you inject your dose, throw away (dispose of) any unused NIVESTYM left in the vials or prefilled syringes. Do not save unused NIVESTYM in the vials or prefilled syringes for later use.

Keep NIVESTYM out of the reach of children.

General information about the safe and effective use of NIVESTYM.

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use NIVESTYM for a condition for which it was not prescribed. Do not give NIVESTYM to other people, even if they have the same symptoms that you have. It may harm them. You can ask your pharmacist or healthcare provider for information about NIVESTYM that is written for healthcare professionals.

What are the ingredients in NIVESTYM?

Active ingredient: (filgrastim-aafi)

Inactive ingredients: acetate, polysorbate 80, sodium, sorbitol, and water for Injection

Manufactured by Hospira, Inc., a Pfizer Company, Lake Forest, IL 60045 USA
US License No. 1974

Distributed by Pfizer Labs, division of Pfizer Inc., New York, NY 10001 USA

LAB-0935-5.0
For more information go to www.pfizer.com or call 1-800-438-1985.

Logo

This Patient Information has been approved by the U.S. Food and Drug Administration     Revised: March 2023

Additional Resources

Chat online with Pfizer Medical Information regarding your inquiry on a Pfizer medicine or vaccine.

Speak with a Pfizer Medical Information Professional regarding your Pfizer medicine or vaccine inquiry.

Available 9AM-5PM ET Monday to Friday; excluding holidays.

 

Submit a medical question for a Pfizer medicine or a vaccine. 

The submission will be reviewed during our standard business hours.

To report an adverse event related to a Pfizer product and you are not part of a clinical trial* for this medication, click the link below to submit your information: 
Pfizer Safety Reporting Site

*If you are involved in a clinical trial for either product, adverse events should be reported to your coordinating study site.

If you cannot use the above website to report an adverse event related to a Pfizer medication, please call (800) 438-1985.

You may also contact the U.S. Food and Drug Administration (FDA) directly to report adverse events or product quality concerns either online at www.fda.gov/medwatch or by calling (800) 332-1088.