Studybox Research

Studybox Research Dual Submission Studies

Influenza A/B Rapid Antigen Test

One integrated study supporting both 510(k) clearance and CLIA waiver.

Studybox

Dual Submission Studies

Antigen-based rapid influenza diagnostic tests were reclassified into Class II with special controls after years of concern about low sensitivity. The special controls set minimum clinical performance that antigen tests must meet against a molecular comparator or viral culture, and require annual analytical reactivity testing against contemporary circulating strains. A clinical study for a new or modified rapid influenza antigen test is designed with those thresholds in mind from the first draft of the protocol.

The study enrolls patients with influenza-like illness during the respiratory season at urgent care centers, physician offices and other point-of-care sites. Each subject contributes a device specimen and a comparator specimen, and the analysis is run separately for influenza A and influenza B. Influenza B is routinely the limiting analyte because it circulates at lower levels in most seasons, and a study that comfortably meets its influenza A target can fall short on B.

Analyte
Influenza A and influenza B nucleoprotein antigens
Therapeutic area
Infectious Disease
Specimens
Nasopharyngeal (NP) Swab, Anterior Nares (Nasal) Swab
Intended-use settings
urgent care, physician office, pharmacy, hospital POC, emergency department
Operators
Medical assistants, nurses and other non-laboratory clinic staff in CLIA-waived settings; laboratory personnel for moderate-complexity 510(k)-only claims.
Comparator
Typically an FDA-cleared influenza A/B RT-PCR assay on a paired specimen; viral culture is the historical alternative and remains an accepted comparator under the special controls.

Dual Submission specifics

What Changes for This Assay on This Pathway.

  • A single prospective study at waived sites with untrained operators can serve both the 510(k) clinical comparison and the waiver demonstration, provided the special-control thresholds are met in that population; this is the typical route for a new rapid influenza antigen test.
  • Multiple seasons may be needed to reach influenza B positives in untrained hands, and the integrated protocol should allow season-to-season continuation without amendment.
  • Analytical studies required by the special controls (limit of detection against reference strains, reactivity, cross-reactivity) run in parallel with the clinical study and are summarized in the same submission.

Endpoints the study must support

  • Positive and negative percent agreement for influenza A and for influenza B separately against the molecular comparator, each with two-sided 95% confidence intervals
  • Performance stratified by specimen type, age group and days since symptom onset
  • Invalid result rate and, for visually read devices, inter-reader agreement

Enrollment realities

Sample size is driven by the number of influenza B positives needed for a lower confidence bound above the special-control threshold; in a mild or A-dominant season this can double planned enrollment. Enrollment concentrates in the weeks of peak circulation, so sites must be active before the season begins. Northern Hemisphere influenza season, typically late fall through early spring, with influenza B often peaking later than influenza A.

How Studybox runs it

Pre-Qualified Sites, Embedded Coordinators.

Waiver evidence depends on genuine intended-use operators in genuine waived settings. Our network of 100+ pre-qualified urgent care, physician office, and point-of-care sites already runs IVD protocols, so operator recruitment and site activation don't start from zero. How we run dual submission studies →

Same assay, other pathways

Relevant FDA guidance

FAQ

Influenza A/B Rapid Antigen Test Study Questions.

01 Who operates the influenza a/b rapid antigen test in a dual submission study?

Medical assistants, nurses and other non-laboratory clinic staff in CLIA-waived settings; laboratory personnel for moderate-complexity 510(k)-only claims.

02 What is the comparator for a influenza a/b rapid antigen test study?

Typically an FDA-cleared influenza A/B RT-PCR assay on a paired specimen; viral culture is the historical alternative and remains an accepted comparator under the special controls.

03 What drives enrollment for a influenza a/b rapid antigen test study?

Sample size is driven by the number of influenza B positives needed for a lower confidence bound above the special-control threshold; in a mild or A-dominant season this can double planned enrollment. Enrollment concentrates in the weeks of peak circulation, so sites must be active before the season begins. Northern Hemisphere influenza season, typically late fall through early spring, with influenza B often peaking later than influenza A.

Let's talk IVD research

Planning a influenza a/b rapid antigen test study?

Tell us the intended use and setting. We'll come back with a site plan, operator strategy, and a realistic activation timeline for the dual submission pathway.