A Study to Evaluate the Efficacy and Safety of Factor IX Gene Therapy With PF-06838435 in Adult Males With Moderately Severe to Severe Hemophilia B (BENEGENE-2)
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ClinicalTrials.gov Identifier: NCT03861273 |
Recruitment Status :
Recruiting
First Posted : March 4, 2019
Last Update Posted : April 15, 2021
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hemophilia B | Biological: PF-06838435/ fidanacogene elaparvovec | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 55 participants |
Allocation: | Non-Randomized |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | PHASE 3, OPEN LABEL, SINGLE ARM STUDY TO EVALUATE EFFICACY AND SAFETY OF FIX GENE TRANSFER WITH PF-06838435 (RAAV-SPARK100-HFIX-PADUA) IN ADULT MALE PARTICIPANTS WITH MODERATELY SEVERE TO SEVERE HEMOPHILIA B (FIX:C <=2%) (BENEGENE-2) |
Actual Study Start Date : | July 29, 2019 |
Estimated Primary Completion Date : | May 25, 2022 |
Estimated Study Completion Date : | May 23, 2027 |

Arm | Intervention/treatment |
---|---|
Experimental: PF-06838435/ fidanacogene elaparvovec |
Biological: PF-06838435/ fidanacogene elaparvovec
Gene Therapy |
- Annualized bleeding rate (ABR) [ Time Frame: First 12 months post PF 06838435 infusion ]
- Vector derived FIX:C level [ Time Frame: Week 12 to 12 months post PF 06838435 infusion ]
- Annualized infusion rate (AIR) of exogenous Factor IX Activity [ Time Frame: First 12 months post study drug infusion ]
- Annualized Factor IX Activity consumption [ Time Frame: 12 months post study drug infusion ]
- Annualized number of bleeding events of specific type: spontaneous and traumatic, and untreated [ Time Frame: 12 months post study drug infusion ]
- Frequency of target joint bleeds [ Time Frame: 12 months post study drug infusion ]
- Percentage of the participants without bleeds [ Time Frame: 12 months post study drug infusion ]
- Change in joint health as measured by the Hemophilia Joint Health Score (HJHS) instrument [ Time Frame: 12 months post study drug infusion ]
- Patient Reported Outcome (PRO) instrument - Hemophilia Quality of Life (Haem A QoL) Physical Health domain [ Time Frame: 12 months post study drug infusion ]
- Patient Reported Outcome (PRO) instrument - Hemophilia Activities List (HAL) Complex Lower Extremity Activities Component Score [ Time Frame: 12 months post study drug infusion ]
- Annualized Bleeding Rate [ Time Frame: Annually for 6 years ]
- Vector derived Factor IX activity (FIX:C) level at steady state [ Time Frame: Annually for 6 years ]
- Annualized infusion rate (AIR) of exogenous Factor IX [ Time Frame: Annually for 6 years ]
- Annualized Factor IX consumption [ Time Frame: Annually for 6 years ]
- Annualized number of bleeding events of specific type: spontaneous and traumatic, and untreated [ Time Frame: Annually for 6 years ]
- Hemophilia Joint Health Score (HJHS) [ Time Frame: Annually for 6 years ]
- Frequency of target joint bleeds [ Time Frame: Annually for 6 years ]
- Patient Reported Outcome (PRO) instrument - Hemophilia Quality of Life (Haem A QoL) Physical Health domain [ Time Frame: Annually for 6 years ]
- Patient Reported Outcome (PRO) instrument - Hemophilia Activities List (HAL) Complex Lower Extremity Activities Component Score [ Time Frame: Annually for 6 years ]
- Incidence and severity of all adverse events collected during the study [ Time Frame: For the duration of 6 years after PF-06838435 infusion ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years to 65 Years (Adult, Older Adult) |
Sexes Eligible for Study: | Male |
Gender Based Eligibility: | Yes |
Accepts Healthy Volunteers: | No |
Inclusion Criteria
- Males who completed 6 months of routine Factor IX prophylaxis therapy during the lead-in study (C0371004) prior to providing consent at the screening visit for this study.
- Documented moderately severe to severe hemophilia B (Factor IX activity < =2%)
- Suspension of prophylaxis therapy for hemophilia B after administration of the study drug
- Laboratory values (hemoglobin, platelets and creatinine) within study specified limits
- Agree to contraception until components of the drug are eliminated from their body
- Capable of giving signed informed consent
Exclusion Criteria
- Anti-AAV Spark100 neutralizing antibodies (nAb) titer >= 1:1.
- History of inhibitor to Factor IX or inhibitor detected during screening.
- Clinical signs or symptoms of decreased response to Factor IX
- Hypersensitivity to Factor IX replacement product or intravenous immunoglobulin administration
- History of chronic infection or other chronic disease
- Any concurrent clinically significant major disease or condition
- Laboratory values at screening visit that are abnormal or outside acceptable study limits
- Significant and/or unstable liver disease, biliary disease, significant liver fibrosis
- Planned surgical procedure requiring Factor IX surgical prophylactic factor treatment 12 months from screening visit
- Use of restricted therapies (e.g., blood products, acetylsalicylic acid [aspirin] or ibuprofen, other investigational therapy, and by-passing agents)
- Previously dosed in a gene therapy research trial at any time or in an interventional clinical study within 12 weeks of screening visit
- Active hepatitis B or C; hepatitis B surface antigen (HBsAg), hepatitis B virus (HBV) deoxyribonucleic acid (DNA) positivity, or hepatitis C virus (HCV) ribonucleic acid (RNA) positivity
- Serological evidence of human immunodeficiency virus HIV-1 or HIV-2 with Cluster of Differentiation 4 positive (CD4+) cell count ≤200 mm3 and/or viral load >20 copies/mL
- Study and sponsor staff and their families involved in the conduct of the study
- Unable to comply with study procedures
- Sensitivity to heparin or heparin induced thrombocytopenia
- Sensitivity to any of the study interventions, or components thereof, or drug or other allergy

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03861273
Contact: Pfizer CT.gov Call Center | 1-800-718-1021 | ClinicalTrials.gov_Inquiries@pfizer.com |

Study Director: | Pfizer CT.gov Call Center | Pfizer |
Responsible Party: | Pfizer |
ClinicalTrials.gov Identifier: | NCT03861273 |
Other Study ID Numbers: |
C0371002 2018-003086-33 ( EudraCT Number ) |
First Posted: | March 4, 2019 Key Record Dates |
Last Update Posted: | April 15, 2021 |
Last Verified: | April 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests. |
URL: | https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Product Manufactured in and Exported from the U.S.: | Yes |
PF 06838435 Hemophilia Factor IX FIX Gene Therapy |
Infusion rAAV Spark100 hFIX Padua BeneGene 2 Hematological Diseases Annualized bleeding rate (ABR) |
Hemophilia A Hemophilia B Blood Coagulation Disorders, Inherited Blood Coagulation Disorders Hematologic Diseases |
Coagulation Protein Disorders Hemorrhagic Disorders Genetic Diseases, Inborn Genetic Diseases, X-Linked |