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Unmet NeedsEfficacyEfficacyStudy DesignsResultsSafety ProfileClinical ScienceClinical ScienceHow BEQVEZ WorksFactor Levels Over TimeVector DNA ClearanceTreating with BEQVEZTreating with BEQVEZTreatment ConsiderationsPatient ProfilesPatient SelectionScreening for Neutralizing AntibodiesDosing ConsiderationsMonitoringResourcesResourcesSupport Services and AccessGetting Ready for BEQVEZDownloads & VideosFAQs
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Screening for Neutralizing Antibodies (NAbs)Screening for Neutralizing Antibodies (NAbs)What you need to know about the companion diagnostic for BEQVEZ eligibility

Testing for NAbs to recombinant AAVRh74var is a required step to help you determine if a patient is eligible to receive BEQVEZ. Please see below for more information1*

Select patients for BEQVEZ based on negative results for the presence of AAVRh74var NAbs1

Pfizer has worked with Labcorp to provide an FDA-approved companion diagnostic. The nAbCyteTM Anti-AAVRh74var HB-FE Assay is FDA approved as a Humanitarian Use Device2†

Additional eligibility criteria need to be assessed prior to infusion with BEQVEZ. Please refer to the full Prescribing Information for complete patient selection criteria.This assay is FDA approved as a Humanitarian Use Device for use as a companion diagnostic in the selection of patients to receive the Pfizer hemophilia B gene therapy, BEQVEZ. The effectiveness of this device for this use has not been demonstrated.2
Testing for NAbs to recombinant AAVRh74var is a required step to help you determine if a patient is eligible to receive BEQVEZ. Please see below for more information1*
Select patients for BEQVEZ based on negative results for the presence of AAVRh74var NAbs1
Pfizer has worked with Labcorp to provide an FDA-approved companion diagnostic. The nAbCyteTM Anti-AAVRh74var HB-FE Assay is FDA approved as a Humanitarian Use Device2†
Additional eligibility criteria need to be assessed prior to infusion with BEQVEZ. Please refer to the full Prescribing Information for complete patient selection criteria.This assay is FDA approved as a Humanitarian Use Device for use as a companion diagnostic in the selection of patients to receive the Pfizer hemophilia B gene therapy, BEQVEZ. The effectiveness of this device for this use has not been demonstrated.2Get started today—NAb testing for BEQVEZ patient eligibility

Labcorp's dedicated program team is available to answer your questions about the program and the process

Register for the Program

  • The nAbCyteTM Assay is a companion diagnostic test approved by the FDA as a Humanitarian Use Device. To order testing, the healthcare provider must complete a one-time enrollment that includes registration with an authorized Institutional Review Board (IRB) for this assay.

Receive Welcome Package

  • Once registration is complete, a representative from the Labcorp program team will provide you with program account setup and detailed instructions for test ordering.

Order the Test

  • Complete the nAbCyteTM-specific test request form (TRF) included in your Welcome Package. Collect the specimen. Shipping instructions will be provided in your Welcome Package.

Receive Results

  • You will receive results within approximately 7–10 days from the time the sample is received at the lab. Results will be delivered based on report receipt preferences.
Keeping you informed: You will be kept up to date throughout the entire testing process, starting with onboarding materials. If help is needed, Labcorp is available to answer account setup, logistics, or assay questions. 

Visit nAbCyteHemB.com to set up your account, and be ready when you see an appropriate patient.

Questions about testing?
Contact Labcorp at [email protected] or call 1-844-294-7361. All patients in the Phase 3 clinical study were screened for NAbs before treatment with BEQVEZ1,3 Download resources and information Continue to Resources Loading
Continue to Resources
LoadingReferences:BEQVEZ. Prescribing Information. Pfizer Inc.; 2024.Data on file. nAbCyte Anti-AAVRh74var Assay Instructions for Use. Pfizer Inc.; 2024.Clinicaltrials.gov. Accessed April 10, 2024. https://clinicaltrials.gov/study/NCT03861273Treating with BEQVEZ
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INDICATION
BEQVEZ is an adeno-associated virus vector-based gene therapy indicated for the treatment of adults with moderate to severe hemophilia B (congenital factor IX deficiency) who:
  • Currently use factor IX prophylaxis therapy, or
  • Have current or historical life-threatening hemorrhage, or
  • Have repeated, serious spontaneous bleeding episodes, and,
  • Do not have neutralizing antibodies to adeno-associated virus serotype 
 Rh74var (AAVRh74var) capsid as detected by an FDA-approved test.
Select patients for therapy based on an FDA-approved companion diagnostic for BEQVEZ.
Important Safety InformationIntravenous administration of a liver-directed AAV vector could potentially lead to liver transaminase elevations. Monitor ALT, AST, and factor IX activity levels once or twice weekly for at least 4 months and institute corticosteroid treatment in response to transaminase elevation and/or decrease in factor IX activity, as required. Perform regular liver ultrasounds (i.e., annually) and alpha-fetoprotein (AFP) testing in patients with risk factors of hepatocellular carcinoma. Monitor for and manage adverse reactions secondary to corticosteroid therapy.

For the first year after BEQVEZ infusion, advise patients to limit alcohol consumption, which may impact liver enzyme elevation and reduce factor IX activity.

Infusion reactions, including hypersensitivity reactions and anaphylaxis, may occur. Closely monitor patients for clinical signs and symptoms of infusion reactions throughout the infusion period and for at least 3 hours after end of infusion. In the event of an infusion reaction, the infusion may be slowed or stopped. If the infusion is stopped, restart at a slower rate when the infusion reaction has resolved.

The integration of liver-targeting AAV vector DNA into the genome may carry the theoretical risk of hepatocellular carcinoma development. Integration of AAV vector DNA into the host cell DNA in other tissues may also occur.

Monitor patients for factor IX activity over time, particularly during the timeframe for corticosteroid treatment decision making, and for inhibitors to factor IX if bleeding is not controlled or plasma factor IX activity levels decrease.

The most common adverse reaction (incidence ≥5%) reported in clinical studies was an increase in transaminases. 62% of patients in the phase 3 study received corticosteroids for transaminase elevation and/or decline in factor IX activity.

Use of hepatotoxic medicinal substances may reduce the efficacy of BEQVEZ, and the risk of serious hepatic reactions may increase following administration.

Prior to BEQVEZ administration, the patient’s existing medications should be reviewed to determine if they should be modified to prevent anticipated interactions. Monitor concomitant medications after BEQVEZ administration and evaluate the need to change concomitant medication based on patient’s hepatic status and risk.

Prior to BEQVEZ infusion, ensure patients are up to date on their vaccinations. If concomitant corticosteroid administration is needed following BEQVEZ infusion, delay administration of live vaccines until the patient has been weaned off corticosteroids.

BEQVEZ is not intended for administration in women.

No studies in animals or clinical studies have been performed to evaluate the potential effects of BEQVEZ on fertility in humans. Vector DNA was shed in semen but declined to undetectable levels in semen within a mean of 1 to 4 months after infusion. Male patients should refrain from donating sperm, be abstinent or use a male condom for up to 6 months after receiving BEQVEZ.

Thoroughly assess liver health and test for pre-existing neutralizing antibodies prior to administering BEQVEZ. Do not administer BEQVEZ to patients with a positive test or a prior history for factor IX inhibitors.

Patients who receive BEQVEZ should be enrolled in a 15-year registry to evaluate the long-term efficacy and safety of hemophilia treatments.

Please see full Prescribing Information for BEQVEZ.Indication

BEQVEZ is an adeno-associated virus vector-based gene therapy indicated for the treatment of adults with moderate to severe hemophilia B (congenital factor IX deficiency) who:

  • Currently use factor IX prophylaxis therapy, or
  • Have current or historical life-threatening hemorrhage, or
  • Have repeated, serious spontaneous bleeding episodes, and,
  • Do not have neutralizing antibodies to adeno-associated virus serotype Rh74var (AAVRh74var) capsid as detected by an FDA-approved test.

Select patients for therapy based on an FDA-approved companion diagnostic for BEQVEZ.