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Pegfilgrastim

  • Biologic
  • Given by a clinician
  • Identity checked
  • Sources last checked 2026-09-04

This page shows what was measured, who it was measured in, and what that does not settle.

What Pegfilgrastim does in the body

The chain reduces removal by the kidneys, so neutrophil-mediated clearance becomes the main route.

Pegfilgrastim is the same protein as filgrastim with a long, inert polymer chain attached to one end. While the neutrophil count is low, clearance is slower. As the count recovers, clearance increases, allowing one dose to provide support through a chemotherapy cycle.

Why people take it. One injection per chemotherapy cycle instead of a daily white cell injection

What happened in people

Bone pain incidence, severity and duration not significantly different from daily filgrastim

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

The recorded finding that sits closest to something a person would notice. Written into the record, not signed off, and it carries no population or interval.

The limit that matters most

That once-per-cycle dosing improves survival relative to daily filgrastim — no trial has tested it

Where it acts
Neutrophil progenitors in the bone marrow
Kind of result
Symptoms and quality of life
Supervision
Professional supervision is normally required. A regulator classifies this substance in a way that restricts how it is supplied.

What the registries record it as

  • The substance registry classes this as protein.

    FDA substance registry · 3A58010674 · read 2026-08-29

Where each sentence above came from

A person wrote this explanation into the record, with the studies named in the path below.

The recorded use, written for a reader without medical training. Not signed off.

A limit recorded against this substance. Not signed off as a reviewed claim.

The four opening statements run to 80 words.

Words this page uses

Four words worth knowing first

Chosen from what this page shows, with each one explained before the word it depends on.

Biomarker

A biomarker is a number from a test that stands in for something about health.

A picture of it, and where the picture fails

A biomarker is like a fuel gauge.

Where that stops being true. A gauge is wired to the tank. Many biomarkers are only loosely tied to health.

What people get wrong. A better number is read as a better life. Several medicines improved a number and helped nobody.

A measurable indicator used as a substitute for a clinical outcome of interest.

Placebo

A placebo is a dummy treatment given so the real one can be compared with it.

A picture of it, and where the picture fails

A placebo is like a blank control in an experiment.

Where that stops being true. A blank does nothing. People given a placebo often do get better.

What people get wrong. A placebo effect is read as imaginary. The improvement is measured and real.

An inactive intervention matched in appearance to the test intervention, used to control for non-specific effects.

Comparator

A comparator is whatever the treatment was measured against.

A picture of it, and where the picture fails

It is like the other runner in a race.

Where that stops being true. A race has one winner. A study can show both arms improved.

What people get wrong. Results are read without asking what the other group got. Beating nothing is not beating a treatment.

The control condition against which the experimental intervention is assessed.

What happened in peopleRead from sources, not yet reviewed

What happened in people

Each card is one study: the exact question it asked, who was in it, and whether it showed what it set out to show.

Percentage of patients developing febrile neutropenia

The study showed what it set out to show

Who was studied
Vogel 2005 placebo-controlled breast cancer trial
How many people
928
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
p < 0.001 (1% versus 17%)
Repeated elsewhere
Replicated

What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Subcutaneous injection: prefilled syringe, single-dose vial, or prefilled syringe with an on-body injector

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

Duration of grade 4 neutropenia in cycle 1 versus daily filgrastim

The study showed what it set out to show

Who was studied
Green 2003 non-inferiority registration trial
How many people
157
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Non-inferiority met (1.8 versus 1.6 days in cycle 1)
Repeated elsewhere
Replicated

What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.

The limits of this study, and where it came from

Main limit. The comparator was an active drug rather than placebo, so this trial establishes equivalence to filgrastim and says nothing about benefit over no treatment.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Subcutaneous injection: prefilled syringe, single-dose vial, or prefilled syringe with an on-body injector

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

What we know
RNAWiki holds 2 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.

What it changes in the bodyRead from sources, not yet reviewed

The path through the body

From what a person takes to what changes. A solid line is a step measured in people. A dashed line is a step nobody has measured that way.

  1. Start

    Pegfilgrastim

    What a person takes: Subcutaneous injection: prefilled syringe, single-dose vial, or prefilled syringe with an on-body injector.

    The measurement behind this step

    Clear, colourless, preservative-free solution at pH 4.0. The 6 mg/0.6 mL prefilled syringe carries no graduation marks and delivers its entire contents. The on-body injector is applied on the day of chemotherapy and delivers the dose approximately 27 hours later, removing a return clinic visit.

  2. Getting in

    One subcutaneous injection the day after chemotherapy

    A single 6 mg injection given about 24 hours after the chemotherapy finishes, either by syringe or by an adhesive on-body device that delivers it later that day.

    Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.

    The measurement behind this step
  3. Getting in

    The PEG chain blocks kidney clearance

    The polymer chain makes the molecule behave as though it were far larger than it is, so the kidney can no longer filter it out of the blood.

    Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.

    The measurement behind this step

    The 20 kDa mPEG raises the hydrodynamic radius well above the glomerular filtration cutoff. Total molecular weight is approximately 39 kDa but the hydrated PEG behaves like a much larger protein.

  4. What it acts on

    Binds G-CSFR on marrow progenitors

    From here the mechanism is identical to filgrastim: it docks on the receptors of immature neutrophils in the marrow.

    Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.

    The measurement behind this step

    N-terminal PEGylation is site-selected precisely because the N-terminus is not part of the receptor-binding interface, so 2:2 G-CSFR complex formation and JAK-STAT signalling are preserved.

  5. The change it makes

    Neutrophils clear the drug as they appear

    The only way the body removes this drug is by the very cells it is making. While your count is low, it stays. As the count comes back, it disappears.

    Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.

    The measurement behind this step

    Neutrophil-mediated receptor internalisation and degradation is the dominant clearance pathway. Serum concentration therefore stays high through the nadir and falls sharply as the neutrophil count recovers, producing self-regulating exposure without therapeutic drug monitoring.

  6. The change it makes

    Marrow reserve released, production accelerated

    Immature cells are pushed to finish maturing and the marrow releases its stored neutrophils earlier than it otherwise would.

    Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.

    The measurement behind this step
  7. What that does for a person

    One injection, the same nadir, far fewer fevers

    The end result is the same recovery as fourteen daily injections, and against no treatment at all, febrile neutropenia falls from about one in six patients to about one in a hundred.

    Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.

    The measurement behind this step

No suggested links are held for this record, so nothing is hidden from this path.

What we know
The record describes 6 steps from taking it to an effect in a person.
How we know it
Each step names the study behind it in the technical detail beside it.
What this does not prove
A change inside the body is a reason to look. It is not a result in a person.
Why it matters
A reader can see exactly where the chain stops being measured in people.
What we still do not know
No reviewed claim binds any of these steps to a named population.

What is missing or unclearRead from sources, not yet reviewed

Were people like you studied?

RNAWiki cannot tell whether a study fits you. It can show who was in it, and where the result stops carrying.

Who was studied

People similar to this profile were included.

  • Patients on chemotherapy regimens carrying a clinically significant risk of febrile neutropenia. It is also the only G-CSF product with an indication for acute radiation syndrome.

Who is missing from the studies

  • Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

What the label states about particular groups

  • On pediatric, the label states: “The safety and effectiveness of ZIEXTENZO for chemotherapy-induced neutropenia and hematopoietic subsyndrome of acute radiation syndrome have been established in pediatric patients aged newborn and older.”

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-30

  • On older people, the label states: “Of the 932 patients with cancer who received pegfilgrastim in clinical studies, 139 (15%) were aged 65 and over, and 18 (2%) were aged 75 and over.”

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-30

  • On people who are pregnant, the label states: “Risk Summary Although available data with pegfilgrastim product use in pregnant women are insufficient to establish whether there is a drug associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes, there are available data from published studies in pregnant women exposed to filgrastim products.”

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-30

  • On people who are breastfeeding, the label states: “Risk Summary There are no data on the presence of pegfilgrastim products in human milk, the effects on the breastfed child, or the effects on milk production.”

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-30

Where the result stopped carrying

  • On-body injector failures generated a dedicated Warnings and Precautions section requiring patients to report suspected non-delivery
  • The acrylic adhesive on the injector causes significant reactions in acrylate-sensitive patients
  • This is a scope explorer, not a diagnosis engine.
  • It shows who was studied so you can see whether people similar to you were included.

RNAWiki cannot tell whether a study fits you. It can show who was in it.

What it would be like to takeRead from sources, not yet reviewed

Why it might seem to do nothing

A real effect and a noticed effect are different things. These are the recorded reasons the two come apart.

It was studied in different people

The people in the studies were not much like the reader.

On this record: Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

The evidence may simply be wrong

Small early studies often do not hold up.

On this record: RNAWiki has not yet published a reviewed conclusion for this use.

Other reasons RNAWiki checked and found nothing for (11)
It was studied for a different goal
The studies measured something else entirely. Nothing in this record points to this reason.
A different form was studied
The studied form is not the form on the shelf. Nothing in this record points to this reason.
There was nothing to correct
Where a level is already normal, topping it up may change nothing. Nothing in this record points to this reason.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment. Nothing in this record points to this reason.
The change is too small to feel
A real change can still sit below what a person notices. Nothing in this record points to this reason.
Day-to-day swing hides it
Sleep, food, stress and time of day move most numbers more than this would. Nothing in this record points to this reason.
Not enough time yet
The studies ran longer than the person has waited. Nothing in this record points to this reason.
It was not taken as studied
Missed days change the result, and studies count them. Nothing in this record points to this reason.
Something else changed at the same time
Two changes at once cannot be told apart afterwards. Nothing in this record points to this reason.
The product may not be what it says
Contents of a sold product are not always what the label states. Nothing in this record points to this reason.
No recorded reason
RNAWiki has nothing stored that would explain it. Nothing in this record points to this reason.

None of these is a reason to take more. Taking more is not a step this page ever suggests.

What it would be like to takeRead from sources, not yet reviewed

What taking it involves

The recorded facts about getting hold of it and using it. Nothing here is a suggestion about what you should do.

How it is supplied

Given by a clinician

Quoted from a source

Where this came from

Copied from a source RNAWiki stored, with the source named.

Read from the recorded approval status.

No source is stored against this line.

Form and route

Subcutaneous injection: prefilled syringe, single-dose vial, or prefilled syringe with an on-body injector

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

The form and route recorded on this substance.

No source is stored against this line.

Who oversees it

Professional supervision is normally required. A regulator classifies this substance in a way that restricts how it is supplied.

Quoted from a source

Where this came from

Copied from a source RNAWiki stored, with the source named.

Suppression classes recorded: S1.

No source is stored against this line.

What is in the pack

0. 6 mL prefilled syringe carries no graduation marks and delivers its entire contents. The on-body injector is applied on the day of chemotherapy and delivers the dose approximately 27 hours later, removing a return clinic visit.

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

Recorded notes on how this is sold and what that means for what is in the pack.

No source is stored against this line.

Where it is registered

Regulatory records are listed in the technical disclosure at the foot of this page.

Counted from records

Where this came from

A count of rows RNAWiki holds. It describes our records, not your body.

Register entries are stored per jurisdiction and shown with their dates.

No source is stored against this line.

Why people stop

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

No record of why people stopped taking it is stored for this substance.

No source is stored against this line.

What it would be like to takeRead from sources, not yet reviewed

What can go wrong

Sorted by where each line came from. A regulator's label and a report somebody sent in are not the same kind of fact.

Worth asking a clinician aboutWritten into the record from the studies named on this page

Fatal splenic rupture, acute respiratory distress syndrome, serious allergic reactions including anaphylaxis, fatal sickle cell crises, glomerulonephritis, capillary leak syndrome, thrombocytopenia, leucocytosis, cutaneous vasculitis and aortitis are labelled risks. The label requires monitoring for myelodysplastic syndrome and acute myeloid leukaemia in breast and lung cancer patients receiving it with chemotherapy or radiotherapy.

Nobody counted how many people took this and were fine, so this cannot be turned into a rate.

Where this came from

Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.

Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

What is missing or unclearRead from sources, not yet reviewed

Does the exact form matter?

Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.

The form that was studied

Subcutaneous injection: prefilled syringe, single-dose vial, or prefilled syringe with an on-body injector

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

The form used in the studies cited on this page.

No source is stored against this line.

What is sold

0. 6 mL prefilled syringe carries no graduation marks and delivers its entire contents. The on-body injector is applied on the day of chemotherapy and delivers the dose approximately 27 hours later, removing a return clinic visit.

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

Recorded notes on which forms are sold and how they compare.

No source is stored against this line.

What is recorded as being sold

  • 16 products list this as an active ingredient in the United States drug directory. 16 of them contain it and nothing else.

    FDA National Drug Code directory · 70114-130 · read 2026-08-29

  • They are sold as injection, injection, solution, liquid and solution, taken subcutaneous.

    FDA National Drug Code directory · 70114-130 · read 2026-08-29

  • The regulator's established pharmacologic class for it is granulocyte colony-stimulating factor [cs], granulocyte-macrophage colony-stimulating factor [cs] and increased myeloid cell production [pe].

    FDA National Drug Code directory · 70114-130 · read 2026-08-29

  • 10 published labels name it as an active ingredient. 10 of them describe this substance alone, which is where its own label text on this page comes from.

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-29

  • Those labels are classed as human prescription drug.

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-29

  • ZIEXTENZO is subcutaneous at 3 DOSAGE FORMS AND STRENGTHS ZIEXTENZO is a clear, colorless to slightly yellowish, preservative-free solution available as: • Injection: 6 mg/0.6 mL in a single-dose prefilled syringe for manual use only., recorded as fda label in effect 2026-05-14 in the United States.

    US prescribing information · 7dada041-6528-4acf-809c-62d271538c9a · read 2026-08-30

Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.

What it would be like to takeRead from sources, not yet reviewed

What you could measure

This one is decided with a clinician, so this section holds questions to ask rather than a plan to run.

Self-experiment planning is not offered for a prescription or clinician-supervised medicine. The questions below are for a clinician or pharmacist.

Questions worth asking

  • Which of the trials of Pegfilgrastim studied people like me?
  • What was measured, and for how long?
  • Was the result a laboratory value or a health outcome?
  • What would we watch for, and when would we stop?

Tracking can show whether something changed for you. It cannot show what caused it.

RNAWiki records evidence. It does not say whether this substance is right for you.

What is missing or unclearRead from sources, not yet reviewed

Claims that go past the evidence

Things said about this substance that sound reasonable, and the exact step that is missing between the evidence and the claim.

Goes past the evidence

That once-per-cycle dosing improves survival relative to daily filgrastim — no trial has tested it

Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.

The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.

What would change this

A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.

RNAWiki has not yet published a reviewed conclusion for this use.

Goes past the evidence

That the radiation indication rests on human evidence; it was granted under the Animal Rule

Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.

The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.

What would change this

A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.

RNAWiki has not yet published a reviewed conclusion for this use.

Goes past the evidence

That an on-body injector is equivalent to a supervised injection; the label has a device-failure warning section

Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.

The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.

What would change this

A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.

RNAWiki has not yet published a reviewed conclusion for this use.

What is missing or unclearRead from sources, not yet reviewed

What nobody knows yet

Open questions, each with why it is open and what would close it.

Missing populations

Which groups were under-represented in the studies has not been recorded.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing long-term data

No completed tested study window is recorded.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

No reviewed conclusion

RNAWiki has not yet published a reviewed conclusion for this use.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing interaction studies

No interaction was found in the registers checked. Not finding one is not the same as showing there is none.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Formulation uncertainty

Several salts, forms or products of Pegfilgrastim are recorded. Results from one form may not transfer to another.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Mechanism not reviewed

No reviewed mechanism story exists for this substance.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

What happened in peopleRead from sources, not yet reviewed

Check any of this yourself

Every line above traced back to the study it came from. This is the technical layer, and the vocabulary changes here.

Every line above can be traced to the study named beside it. Follow the link and read it.

Against placebo: febrile neutropenia fell from 17% to 1%
In plain words
In 928 breast cancer patients on docetaxel, one injection per cycle reduced fevers with low white counts from about one in six patients to about one in a hundred.
What was measured
Febrile neutropenia 1% versus 17% (p < 0.001) in 928 patients
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Multicentre, double-blind, placebo-controlled phase III trial. Patients received placebo (n = 465) or pegfilgrastim 6 mg subcutaneously on day 2 of each 21-day cycle of docetaxel 100 mg/m2. Febrile neutropenia occurred in 1% versus 17% (p < 0.001), febrile-neutropenia-related hospitalisation in 1% versus 14% (p < 0.001), and intravenous anti-infective use in 2% versus 10% (p < 0.001).
Source
Vogel CL et al. J Clin Oncol 2005;23:1178-1184
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
verified
Review state
Written into the record, not signed off as a reviewed claim
One injection matched fourteen: the non-inferiority registration trial
In plain words
A single fixed 6 mg dose performed the same as daily filgrastim injections on every efficacy measure across four chemotherapy cycles.
What was measured
Grade 4 neutropenia duration 1.8 versus 1.6 days in cycle 1
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Randomised, double-blind, multicentre phase III study, 157 patients on doxorubicin 60 mg/m2 and docetaxel 75 mg/m2. Mean duration of grade 4 neutropenia in cycle 1 was 1.8 days with pegfilgrastim and 1.6 days with daily filgrastim. Results in cycles 2 to 4 were consistent. Febrile neutropenia trended lower with pegfilgrastim across all cycles, 13% versus 20%. Safety and tolerability were comparable.
Source
Green MD et al. Ann Oncol 2003;14:29-35
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
verified
Review state
Written into the record, not signed off as a reviewed claim
Approved on a surrogate, not on survival
In plain words
The endpoint that got this drug licensed was how many days the white count stayed critically low, compared with a drug that was already on the market. No trial has shown it makes people live longer than daily filgrastim.
What was measured
That once-per-cycle dosing produces better patient outcomes rather than better adherence to the same effect
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The pivotal comparison was non-inferiority in duration of grade 4 neutropenia against daily filgrastim, in 157 and 310 patients respectively. Duration of severe neutropenia is a laboratory surrogate; the placebo-controlled trial then measured febrile neutropenia, which is a clinical event, but neither design was powered for survival. The convenience advantage of one injection per cycle is real and measurable; a survival advantage over daily filgrastim has never been demonstrated because no trial has looked for one.
Source
Green MD et al. Ann Oncol 2003;14:29-35; Vogel CL et al. J Clin Oncol 2005;23:1178-1184
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
caution
Review state
Written into the record, not signed off as a reviewed claim
The on-body injector has its own warning section
In plain words
The device designed to remove the clinic visit can fail to deliver the dose, and the label tells patients to report it if they suspect it has.
What was measured
Not recorded
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
Section 5.12 of the US prescribing information, Potential Device Failures, instructs that patients be told to notify their healthcare provider if they suspect the on-body injector may not have performed as intended, so that the need for a replacement dose can be assessed. Section 5.4 separately warns that the acrylic adhesive used by the injector can cause significant reactions in patients sensitive to acrylates. A delivery system introduced to improve adherence therefore introduced a failure mode that the daily syringe did not have.
Source
NEULASTA US prescribing information, Warnings and Precautions sections 5.4 and 5.12
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
caution
Review state
Written into the record, not signed off as a reviewed claim
Biosimilar entry from 2018 was the price event, not a new trial
In plain words
What changed the economics of this drug was not new evidence about whether it works. It was four biosimilars arriving after the patents ran out.
What was measured
First two US pegfilgrastim biosimilar approvals: 4 June 2018 and 2 November 2018
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Fulphila (pegfilgrastim-jmdb, BLA 761075) was approved 4 June 2018 and Udenyca (pegfilgrastim-cbqv, BLA 761039) on 2 November 2018, followed by further entrants. Pegfilgrastim became one of the first US biologic markets with meaningful multi-source competition, and the clinical question the biosimilar programmes answered was analytical and pharmacodynamic comparability rather than a fresh outcome trial. Nothing about the underlying evidence for the molecule changed; the price did.
Source
Drugs@FDA, BLA 761075 (Fulphila) and BLA 761039 (Udenyca)
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
verified
Review state
Written into the record, not signed off as a reviewed claim
A radiation indication granted without a human efficacy trial
In plain words
The indication for radiation sickness could not ethically be tested in people, so it was granted on animal data under a specific regulatory rule.
What was measured
That the haematopoietic syndrome of acute radiation syndrome responds to G-CSF in humans the way it does in irradiated animals
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Pegfilgrastim carries an indication to increase survival in patients acutely exposed to myelosuppressive doses of radiation. Efficacy studies in humans cannot be ethically or feasibly conducted, so this indication rests on the FDA Animal Rule pathway and on the mechanistic continuity with chemotherapy-induced neutropenia. It is a legitimate regulatory decision and it is also, by construction, an indication with no human efficacy evidence behind it.
Source
NEULASTA US prescribing information, Indications and Usage
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
caution
Review state
Written into the record, not signed off as a reviewed claim

How many documents were read

  • 2 documents were read for this substance.

    RNAWiki source record

  • 2 of them state the same halfLife, and they agree.

    RNAWiki source record

Where else this substance is registered

FDA substance identifier (UNII)
3A58010674
RxNorm concept
727539

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    Suppression classes recorded: S1.

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What is missing or unclearRead from sources, not yet reviewed

How this medicine reached us

Kept near the foot of the page. A historical event moves up only when it changes something about this substance today.

  1. Withdrawn in United States, 2026, for "Temperature Abuse. 116 cartons with specific serial numbers of Lot 2199821, were stored incorrectly in a controlled room temperature environment instead of the required refrigerated environment." (openFDA drug enforcement Class I recall)

What the approval register records

  • 1 approved application covers products containing this substance. The earliest was BLA125031, approved 20020131 to AMGEN.

    Drugs@FDA application register · BLA125031 · read 2026-08-29

  • Marketing status on the register: prescription.

    Drugs@FDA application register · BLA125031 · read 2026-08-29

  • The earliest marketing start date recorded for a listed product is 20020401.

    FDA National Drug Code directory · 70114-130 · read 2026-08-29

What is missing or unclearRead from sources, not yet reviewed

What to learn next

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7 questions this page could not answer

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  • What was measured, goal by goal — found nothing in the sources checked.
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  • Felt, measured, or meaningful — found nothing in the sources checked.
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Everything above is built from what is below. This layer keeps the technical vocabulary, record identifiers and every stored row, so a reader who wants to check the page can.

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Written for a clinical reader, and about the medicine as a whole rather than about one indication, population and set of trials. RNAWiki does not treat it as a programme conclusion and no reviewer has signed it off in that form. It is here word for word because it is what the record holds.

Filgrastim with a 20 kDa polyethylene glycol chain on its N-terminal methionine, which makes neutrophils themselves the main route of clearance; one 6 mg injection per cycle matched fourteen days of filgrastim, and against placebo it cut febrile neutropenia from 17% to 1%.

Recorded evidence blocks (10)

On the Pegfilgrastim label: indicated for what?


"Neulasta is a leukocyte growth factor indicated in adult and pediatric patients to Decrease the incidence of infection, as manifested by febrile neutropenia, in patients with non-myeloid malignancies receiving myelosuppressive anti-cancer drugs associated with a clinically significant incidence of febrile neutropenia.…": indications and usage on Pegfilgrastim's label. DailyMed label · fdfe5d72-6b80-435a-afa4-c5d74dd852ce · 2026-08-10

277 registered trials of Pegfilgrastim — at which phases?


Registered studies posting no result
170 of 277

277 registered studies of Pegfilgrastim: 158 phase2, 71 phase1, 51 phase3, 11 phase4, 10 na, 5 na or unstated, 2 early phase1. CLINICALTRIALS_SNAPSHOT · 2026-09-01

271 with a PubMed record

Show the evidence
  • phase2
    158
  • phase1
    71
  • phase3
    51
  • phase4
    11
  • na
    10
  • na or unstated
    5
9 more recorded rows
  • early phase1
    2
  • completed
    176
  • terminated
    34
  • recruiting
    23
  • active not recruiting
    21
  • unknown
    19
  • withdrawn
    2
  • no longer available
    1
  • not yet recruiting
    1

recorded 2026-09-01 · last checked 2026-09-04

34 of Pegfilgrastim's trials stopped: safety, futility/efficacy, accrual/recruitment, funding/business, sponsor decision unspecified, other?


safety (4), futility/efficacy (1), accrual/recruitment (14), funding/business (5), sponsor decision unspecified (1) and other (9): Pegfilgrastim's stop wording, clustered. CLINICALTRIALS_SNAPSHOT · 2026-09-01

"Lack of accrual"; 34 of 277 registered studies

Show the evidence

Trial

  • NCT00074165
    terminated; "Lack of accrual"
  • NCT00077103
    terminated; "slow accrual"
  • NCT00080626
    terminated; "low accrual"
  • NCT00113386
    terminated; "This study terminated early due to low accrual."
  • NCT00346229
    terminated; "Funding"
  • NCT00352118
    terminated; "Low dose radiation treatment was not appropriate for these patients."
14 further recorded trials
  • NCT00503984
    terminated; "Withdrawal of Funding"
  • NCT00632827
    terminated; "Manufacturing shortage of both Diftitox and Doxil"
  • NCT00679029
    terminated; "drug toxicity"
  • NCT00689884
    terminated; "Lack of enrollment."
  • NCT00695370
    terminated; "Recruiting or enrolling participants has halted and will not resume"
  • NCT01012297
    terminated; "The study was targeted to accrue 130 patients, but closed early for futility."
  • NCT01313884
    terminated; "Study did not reach primary objective; study did not accrue enough patients."
  • NCT01498588
    terminated; "Slow accrual"
  • NCT01541072
    terminated; "Number of enrolled patients was insufficient during planned inclusion time."
  • NCT01639521
    withdrawn; "Lack of funding"
  • NCT01692691
    terminated; "PI decision"
  • NCT02087176
    terminated; "The study was terminated early by the sponsor."
  • NCT02157116
    terminated; "Insufficient accrual to meet analysis goals"
  • NCT02392039
    terminated; "Slow Accrual"

recorded 2026-09-01 · last checked 2026-09-04

Human studies of Pegfilgrastim used pegfilgrastim 12 mg — over how long?


studies of Pegfilgrastim used the recorded amount. ClinicalTrials.gov · 2026-09-01

5 recorded entries; human; also "pegfilgrastim 12 mg", "pegfilgrastim 6 mg", "Neulasta (pegfilgrastim) 6mg"

Show the evidence

human

  • NCT00066092
    pegfilgrastim 12 mg
  • NCT00066092
    pegfilgrastim 6 mg
  • NCT01328938
    Neulasta (pegfilgrastim) 6mg
  • NCT01840579
    G-CSF (pegfilgrastim) 3.6 mg
  • NCT01933932
    Pegfilgrastim 6 mg

recorded 2026-09-01 · last checked 2026-09-04

Pegfilgrastim's half-life is 15 to 80 hours — which schedules were studied?


15 to 80 hours, the half-life Pegfilgrastim's label states: "The half-life of Neulasta ranged from 15 to 80 hours after subcutaneous injection." DailyMed label · fdfe5d72-6b80-435a-afa4-c5d74dd852ce · 2026-08-10

Show the evidence
  • half life pharmacokinetics
    15 to 80 hours; The half-life of Neulasta ranged from 15 to 80 hours after subcutaneous injection.

recorded 2026-08-10 · last checked 2026-09-04

Which running trial of Pegfilgrastim could settle lifespan?


NCT01933932 measures Progression-Free Survival (PFS), reading out 2026-12-31.

10 open trials; n 510; "Assess Efficacy & Safety of Selumetinib in Combination With Docetaxel in Patients Receiving 2nd Line Treatment for v-Ki-ras2 Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) Positive NSCLC"

Show the evidence

Trial

  • NCT01933932
    "Assess Efficacy & Safety of Selumetinib in Combination With Docetaxel in Patients Receiving 2nd Line Treatment for v-Ki-ras2 Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) Positive NSCLC"; n 510; "Progression-Free Survival (PFS)"; 2026-12-31
  • NCT04759586
    "Nivolumab in Combination With Chemo-Immunotherapy for the Treatment of Newly Diagnosed Primary Mediastinal B-Cell Lymphoma"; n 244; "Progression-free survival (PFS)"; 2026-12-31
  • NCT00070564
    "S0221 Adjuvant Doxorubicin, Cyclophosphamide, and Paclitaxel in Treating Patients With Breast Cancer"; n 3294; "Disease-free Survival"; 2027-01
  • NCT03907488
    "Immunotherapy (Nivolumab or Brentuximab Vedotin) Plus Combination Chemotherapy in Treating Patients With Newly Diagnosed Stage III-IV Classic Hodgkin Lymphoma"; n 994; "Progression Free Survival (PFS)"; 2027-03-28
  • NCT04628767
    "Testing the Addition of MEDI4736 (Durvalumab) to Chemotherapy Before Surgery for Patients With High-Grade Upper Urinary Tract Cancer"; n 131; "Event-free survival (EFS) (Cisplatin eligible cohort: Arms A and B)"; 2027-09-30
  • NCT00433420
    "Combination Chemotherapy With or Without Fluorouracil and/or Pegfilgrastim in Treating Women With Node-Positive Breast Cancer"; n 2000; "Disease-free survival"; 2027-12
4 further recorded trials
  • NCT06188676
    "Multicenter Study of Safety and Efficacy Nivolumab at the Fixed Dose 40 mg (Nivo40) in Combination With Chemo-Immunotherapy for the Treatment of Newly Diagnosed PMBL"; n 100; "Progression-free survival (PFS)"; 2029-04-01
  • NCT01871766
    "Risk-Adapted Focal Proton Beam Radiation and/or Surgery in Patients With Low, Intermediate and High Risk Rhabdomyosarcoma Receiving Standard or Intensified Chemotherapy"; n 115; "Event-free survival (intermediate risk arm)"; 2030-06
  • NCT04685616
    "Brentuximab Vedotin in Early Stage Hodgkin Lymphoma"; n 1042; "Progression free survival (PFS)"; 2032-09
  • NCT05535166
    "Molecular and Clinical Risk-Directed Therapy for Infants and Young Children With Newly Diagnosed Medulloblastoma"; n 130; "Progression free survival of SHH-2 infant (0-2.99 years) and young child (3-4.99 years) medulloblastoma patients treated with systemic HD-MTX-based chemotherapy only."; 2035-07

Which 83 trials of Pegfilgrastim posted no result?


Posted no result
83 of 83 completed trials
Registrations
NCT00004192, NCT00117897, NCT00117910, NCT00035594, NCT00115206 and NCT00114764, and 77 more
Completion dates
oldest 2001-03-16; newest 2024-05-01
Show the evidence

Trial

  • NCT00004192
    2001-03-16
  • NCT00117897
    2004-02
  • NCT00117910
    2004-05
  • NCT00035594
    2004-06
  • NCT00115206
    2004-07
  • NCT00114764
    2004-08
14 further recorded trials
  • NCT00066092
    2004-10
  • NCT00117442
    2004-12
  • NCT00277160
    2005-01
  • NCT00115193
    2005-08
  • NCT00283621
    2006-04-12
  • NCT00074178
    2006-07
  • NCT00035620
    2007-04
  • NCT00067639
    2007-04
  • NCT00146562
    2007-05
  • NCT00217503
    2007-06
  • NCT00310089
    2007-07
  • NCT00431080
    2007-10
  • NCT02782845
    2007-10
  • NCT00261313
    2007-12

At the median, Pegfilgrastim's trials enrolled 55 people — anything larger?


Median enrolment
55
Largest enrolment
4400
Registered trials counted
267

What do 33027 spontaneous reports say about Pegfilgrastim — and not say?


These are reports people sent to a regulator. They do not show the medicine caused the reaction. Nobody counted how many people took the medicine and reported nothing. The same event can be reported more than once, and many reports are incomplete. News coverage, lawsuits and new warnings change how often people report. A count is not a rate and not a risk.

Pegfilgrastim appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 33027 reaction mentions were counted: wrong technique in product usage process 7895; unintentional medical device removal 6546; device adhesion issue 5355; device use error 4867. FAERS via Open Targets · CHEMBL1201568 · 2026-06-24

Show the evidence
  • wrong technique in product usage process
    7895
  • unintentional medical device removal
    6546
  • device adhesion issue
    5355
  • device use error
    4867
  • febrile neutropenia
    2367
  • bone pain
    1743
4 more recorded rows
  • neutropenia
    1657
  • application site haemorrhage
    1049
  • application site pain
    792
  • occupational exposure to product
    756

recorded 2026-06-24 · last checked 2026-09-04

Which 10 reactions does Pegfilgrastim's label not list?


application site haemorrhage, application site pain and bone pain and 7 more reported for Pegfilgrastim, absent from its label. FAERS via Open Targets · CHEMBL1201568 · 2026-06-24

2 label terms; 10 reported and unlisted; fdfe5d72-6b80-435a-afa4-c5d74dd852ce

Show the evidence
  • application site haemorrhage
    count not stated
  • application site pain
    count not stated
  • bone pain
    count not stated
  • device adhesion issue
    count not stated
  • device use error
    count not stated
  • febrile neutropenia
    count not stated
4 more recorded rows
  • neutropenia
    count not stated
  • occupational exposure to product
    count not stated
  • unintentional medical device removal
    count not stated
  • wrong technique in product usage process
    count not stated

recorded 2026-06-24 · last checked 2026-09-04

Where it is registered

Where it’s registered

Withdrawn in United States, 2026, for "Temperature Abuse. 116 cartons with specific serial numbers of Lot 2199821, were stored incorrectly in a controlled room temperature environment instead of the required refrigerated environment." (openFDA drug enforcement Class I recall)

Identifiers, relations and other names

The exact record

ChEMBL id
CHEMBL1201568
CAS number
208265-92-3
RxCUI
338036
Also called
Ziextenzo, Udenyca, B-12019, B12019, Cegfila, Chs-1701, Fulphila, Fylnetra, Granulocyte colony-stimulating factor pegfilgrastim, Hsp-130, La-ep2006, Lupifil-p
Trade name
Grasustek, Neulasta, Neulasta sureclick, Pelgraz, Ristempa, Armlupeg
Development code
LA EP 2006, MYL-1401H, TPI-120
Sources (7)

Sources

1 more source

ChEMBL 37 — CC BY-SA 3.0 Unported · ChEMBL ATC CC BY-SA · ClinicalTrials.gov — US Government work · Open Targets 26.06 — CC0 · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md · openFDA / DailyMed — US Government work · openFDA enforcement — US Government work

How these records are assembled · Which registers were checked

Index-quality checks
  • identity passed: no open identity hold
  • required summary fields resolved: 4 required field(s) not terminal: Why people use it, Best-supported result, Biggest unanswered question, Human evidence
  • public claims reviewed: 0 reviewed claim(s); drafts are never rendered
  • source coverage passed: 7 source rows
  • no critical contamination: no quarantine open
  • canonical metadata passed: slug and display name present
  • no raw internal fields: enforced by the copy-contract test over the rendered page

This is a record of evidence. It is not medical advice, and it does not say this substance suits you. Nothing here says any substance on RNAWiki is appropriate for a child.