Trial · NCT01825200

Comparison of the Safety of Flublok® Versus Licensed IIV in Healthy, Medically Stable Adults ≥ 50 Years of Age

NCT01825200, Phase 3, Completed, Protein Sciences Corporation; results first posted 2015-02-18

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Comparison of the Safety of Flublok® Versus Licensed IIV in Healthy, Medically Stable Adults ≥ 50 Years of Age. Trials, record NCT01825200. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT01825200

On this page

Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: Comparison of the Safety of Flublok® Versus Licensed IIV in Healthy, Medically Stable Adults ≥ 50 Years of Age
NCT number: NCT01825200
Status: Completed
Phases: Phase 3
Enrollment: 2,640 participants, actual
Lead sponsor: Protein Sciences Corporation
Conditions: Influenza
Interventions: Flublok, Afluria
First posted: 2013-04-05
Last updated: 2015-02-18
Results first posted: 2015-02-18
Limitations and caveats: Rash, urticaria, swelling and edema were self-reported by subjects and most were not observed by investigators. Review by independent experts indicated that 42 of 52 subject-reported events did not represent Type 1 (IgE-mediated) hypersensitivity.

Source ClinicalTrials.gov

Registered outcomes4

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	Number of Participants With Common Hypersensitivity Reactions as Measure of Safety	30 Days	Number of participants who experience a pre-defined common systemic hypersensitivity adverse event, including rash, urticaria, swelling or edema through Day 30 post-vaccine administration.
Secondary	Subjects With at Least One Unsolicited Adverse Event in the 30 Days Following Vaccine Administration	30 Days	Subjects with at least one serious adverse event and subjects with at least one medically-attended unsolicited adverse event occurring during the 30 days following vaccine administration
Secondary	Number of Participants With Local and Systemic Events Reported as a Measure of Safety	7 Days	Number of solicited local and systemic events of reactogenicity reported with the help of a memory aid during the seven days following vaccine administration.
Secondary	Subjects With at Least One Hypersensitivity Event Reported on Day 0 and Days 0-7 Following Vaccine Administration as a Measure of Safety	7 Days	Subjects with at least one pre-defined common systemic hypersensitivity adverse event, including rash, urticaria, swelling or non-dependent edema on Day 0 and for Days 0 to 7 following vaccine administration

Source ClinicalTrials.gov

Outcomes4

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Number of Participants With Common Hypersensitivity Reactions as Measure of Safety	30 Days	The primary analysis population, includes all randomized subjects who received a dose of study vaccine and for whom some safety data were available after administration of vaccine. Subjects were analyzed according to the vaccine received, regardless of whether this was the treatment group to which they were randomized.	participants	NUMBER
SECONDARY	Subjects With at Least One Unsolicited Adverse Event in the 30 Days Following Vaccine Administration	30 Days	The primary analysis population, includes all randomized subjects who received a dose of study vaccine and for whom some safety data were available after administration of vaccine. Subjects were analyzed according to the vaccine received, regardless of whether this was the treatment group to which they were randomized.	participants	NUMBER
SECONDARY	Number of Participants With Local and Systemic Events Reported as a Measure of Safety	7 Days	The primary analysis population, includes all randomized subjects who received a dose of study vaccine and for whom some safety data were available after administration of vaccine. Subjects were analyzed according to the vaccine received, regardless of whether this was the treatment group to which they were randomized.	participants	NUMBER
SECONDARY	Subjects With at Least One Hypersensitivity Event Reported on Day 0 and Days 0-7 Following Vaccine Administration as a Measure of Safety	7 Days	The primary analysis population, includes all randomized subjects who received a dose of study vaccine and for whom some safety data were available after administration of vaccine. Subjects were analyzed according to the vaccine received, regardless of whether this was the treatment group to which they were randomized.	participants	NUMBER

Source ClinicalTrials.gov

Results by group12

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Category	Value	Units
Number of Participants With Common Hypersensitivity Reactions as Measure of Safety	Flublok		31	participants
Number of Participants With Common Hypersensitivity Reactions as Measure of Safety	Afluria		21	participants
Subjects With at Least One Unsolicited Adverse Event in the 30 Days Following Vaccine Administration	Flublok	Serious Adverse Events (SAEs)	5	participants
Subjects With at Least One Unsolicited Adverse Event in the 30 Days Following Vaccine Administration	Afluria	Serious Adverse Events (SAEs)	10	participants
Subjects With at Least One Unsolicited Adverse Event in the 30 Days Following Vaccine Administration	Flublok	Medically-Attended Unsolicited Adverse Events	53	participants
Subjects With at Least One Unsolicited Adverse Event in the 30 Days Following Vaccine Administration	Afluria	Medically-Attended Unsolicited Adverse Events	51	participants
Number of Participants With Local and Systemic Events Reported as a Measure of Safety	Flublok		432	participants
Number of Participants With Local and Systemic Events Reported as a Measure of Safety	Afluria		480	participants
Subjects With at Least One Hypersensitivity Event Reported on Day 0 and Days 0-7 Following Vaccine Administration as a Measure of Safety	Flublok	Day 0	5	participants
Subjects With at Least One Hypersensitivity Event Reported on Day 0 and Days 0-7 Following Vaccine Administration as a Measure of Safety	Afluria	Day 0	3	participants

1 to 10 of 12Source ClinicalTrials.gov

See all 12 results by group

Participant flow6

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	Flublok	1,319
Overall Study	STARTED	Afluria	1,321
Overall Study	COMPLETED	Flublok	1,314
Overall Study	COMPLETED	Afluria	1,314
Overall Study	NOT COMPLETED	Flublok	5
Overall Study	NOT COMPLETED	Afluria	7

Source ClinicalTrials.gov

Adverse events28

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk	Events
other	Headache	Nervous system disorders	Flublok	8	1,314	8
other	Headache	Nervous system disorders	Afluria	12	1,313	12
other	Diarrhea	Gastrointestinal disorders	Flublok	12	1,314	12
other	Diarrhea	Gastrointestinal disorders	Afluria	4	1,313	4
serious	Cerebellar Stroke Syndrome	Nervous system disorders	Flublok	0	1,314	0
serious	Cerebellar Stroke Syndrome	Nervous system disorders	Afluria	1	1,313	1
serious	Sepsis	Infections and infestations	Flublok	0	1,314	0
serious	Sepsis	Infections and infestations	Afluria	2	1,313	2
serious	Myocardial Infarction	Cardiac disorders	Flublok	1	1,314	1
serious	Myocardial Infarction	Cardiac disorders	Afluria	2	1,313	2

1 to 10 of 28Source ClinicalTrials.gov

See all 28 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Flublok
Total, all-cause mortality	Afluria
Total, other adverse events	Flublok	20	1,314
Total, other adverse events	Afluria	16	1,313
Total, serious adverse events	Flublok	5	1,314
Total, serious adverse events	Afluria	10	1,313

Source ClinicalTrials.gov

Papers1

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as
26529070	DERIVED

Source PubMed

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons3

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
Flublok vs Afluria: Number of Participants With Local and Systemic Events Reported as a Measure of Safety	Trial comparisons
Flublok vs Afluria: Number of Participants With Common Hypersensitivity Reactions as Measure of Safety	Trial comparisons
Flublok vs Afluria: serious adverse events	Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

GET https://conductscience.org/api/trials/v1/NCT01825200

GET https://conductscience.org/api/trials/v1/NCT01825200/events?page=2

API reference For AI assistants