A Clinical Trial Investigating the Safety and Biological Activity of the Antibody BNT351 in Adults Living Without and With HIV
A Phase I First-in-human Clinical Trial to Evaluate the Safety, Pharmacokinetics, and Antiviral Activity of the Broadly Neutralizing Antibody BNT351 in Adults Living Without and With HIV
2 other identifiers
interventional
61
2 countries
3
Brief Summary
This study will test the safety and blood levels of the antibody BNT351 in people living without and with human immunodeficiency virus (HIV). This study will also test the anti-viral activity of BNT351 in people living with HIV (PLWH) with detectable virus levels. The main goals of this study are:
- To learn about the safety of BNT351 and check for side effects.
- To measure the amount of BNT351 antibody in blood over time.
- To test the amount of HIV in the blood at different times after treatment with BNT351 in people living with HIV.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_1
Started Feb 2026
3 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
January 30, 2026
CompletedFirst Posted
Study publicly available on registry
February 6, 2026
CompletedStudy Start
First participant enrolled
February 9, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
June 1, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
June 1, 2027
March 19, 2026
March 1, 2026
1.3 years
January 30, 2026
March 18, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (13)
Parts A and B - Occurrence of at least one adverse event (AE)
Per part, by cohort/dose
From dosing to 56 days post-dose
Parts A and B - Occurrence of at least one serious AE (SAE)
Per part, by cohort/dose
From dosing through the end of study (up to a maximum of 279 days post-dose)
Parts A and B (except for Cohort A1) - Occurrence of infusion-related reactions (IRRs) Grade ≥2 (graded based on National Cancer Institute Common Terminology Criteria for AEs [NCI CTCAE] version 5.0 as specified in the protocol)
Per part, by cohort/dose
From the start of IV dosing through 72 hours after the start of IV dosing
Parts A and B - Occurrence of at least one solicited local reaction (pain/tenderness, erythema/redness, induration/swelling) at the investigational medicinal product administration site
Per part, by cohort/dose
From dosing through 7 days post-dose
Parts A and B- Occurrence of at least one solicited systemic event (vomiting, diarrhea, headache, fatigue/malaise, myalgia/arthralgia, fever)
Per part, by cohort/dose
From dosing through 7 days post-dose
Parts A and B- Assessment of area under the concentration-time curve of BNT351
Per part, by cohort/dose
From pre-dose to last quantifiable timepoint (up to a maximum of 279 days post-dose)
Parts A and B - Assessment of maximum concentration of BNT351
Per part, by cohort/dose
From dosing through 7 days post-dose
Part B - Occurrence of any acquired immunodeficiency syndrome (AIDS)-defining illness or opportunistic infection as defined in the protocol
From dosing up to the time of cART initiation (up to a maximum of 56 days post-dose)
Part B - Occurrence of absolute CD4+ T cell count <350 cells/µL or CD4+ T cell count <15% of total lymphocyte count
From dosing up to the time of cART initiation (up to a maximum of 56 days post-dose)
Part B - Change from baseline in HIV log10 plasma viral load prior to cART initiation
At 7, 14, 21, 28, 35, 42, 49, and 56 days post-dose
Part B - Maximum decrease from baseline in HIV log10 plasma viral load prior to cART initiation
From baseline up to the time of cART initiation (up to a maximum of 56 days post-dose)
Part B - Time from dosing to lowest viral load prior to cART initiation
From dosing up to the time of cART initiation (up to a maximum of 56 days post-dose)
Part B - Time from dosing to viral rebound defined as HIV-1 RNA viral load increase >0.75 log10 copies/mL from nadir (i.e., lowest HIV-1 RNA viral load from 7 days post-dose (Visit 3) and through pre-cART initiation)
From dosing up to the time of cART initiation (up to a maximum of 56 days post-dose)
Secondary Outcomes (3)
Parts A and B - Incidence of detectable BNT351 anti-drug antibodies in serum
From baseline until the end of study (up to a maximum of 279 days post-dose)
Part B - Magnitude of cluster of differentiation 4 positive (CD4+) T cell counts
At dosing, 28 and 56 days post-dose or at time of cART initiation (up to a maximum of 56 days post-dose)
Parts B - Change from baseline in CD4+ T cell count
At 28 days post-dose and at time of cART initiation (up to a maximum of 56 days post-dose)
Study Arms (5)
Part A - Cohort A1
EXPERIMENTALPLWOH will be randomized to BNT351 (at a protocol defined dose level) or placebo (2:1)
Part A - Cohort A2
EXPERIMENTALPLWOH will be randomized to BNT351 (at a protocol defined dose level) or placebo (3:1)
Part A - Cohort A3
EXPERIMENTALPLWOH will be randomized to BNT351 (at a protocol defined dose level) or placebo (3:1)
Part A - Cohort A4
EXPERIMENTALPLWOH will be randomized to BNT351 (at a protocol defined dose level) or placebo (3:1)
Part B - Cohort B1
EXPERIMENTALPLWH will receive BNT351 at a protocol-defined dose level. cART will start 56 days post-BNT351 dosing or earlier.
Interventions
Eligibility Criteria
You may qualify if:
- Part A:
- Are HIV-1 and HIV-2 negative at Visit 0.
- Starting at Visit 0 and continuously until the last planned visit in this study are individuals who:
- Are assessed by the investigator as having a low likelihood of acquiring HIV and are committed to avoiding behaviors associated with a higher likelihood of acquiring HIV until the End of Study Visit.
- Agree to discuss HIV disease risks;
- Agree to HIV acquisition risk reduction counseling;
- Part B:
- Are HIV-1 positive and HIV-2 negative at Visit 0.
- Individuals who at Visit 0:
- Are cART-naïve individuals who were diagnosed with HIV-1 infection ≤12 months prior to screening, OR are individuals who have discontinued cART and who were diagnosed with HIV-1 infection ≤12 months prior to screening or ≤18 months if this is found to be acceptable after discussion on a case-by-case basis with the sponsor's medical monitor.
- If cART-experienced, have discontinued cART for at least 4 weeks before screening (if the individual was taking long-acting antiretroviral therapy \[ART\]), see the following bullet). For individuals who have discontinued cART: Are able to comply with study procedures and assessments in the investigator's judgment.
- Have never received lenacapavir and have not received other long-acting ARTs in the last 6 months (i.e., intramuscular cabotegravir, cabotegravir-rilpivirine).
- Have a CD4+ T cell count of ≥400 cells/µL and plasma HIV-1 RNA levels between 1,000-100,000 copies/mL at screening.
- Are willing to initiate cART at a protocol-defined timepoint (56 days post-dose, or earlier if meeting early cART start criteria or at investigator's discretion).
- Are willing to undergo HIV transmission risk reduction counseling and to maintain low-risk behavior to protect their partners.
You may not qualify if:
- Part A:
- Have received an HIV vaccination or HIV broadly neutralizing antibody in another clinical study.
- Have a known or suspected impairment/alteration of immune function or immunodeficiency, including receipt of any immunostimulant, immunomodulator, immunosuppressive medication, immunoglobulin, blood product, or oral or parenteral steroid within 60 days prior to Day 1 or planned administration during the study. The following exception applies: Use of inhaled, intranasal, topical, or locally injected corticosteroids (e.g., intraarticular or intrabursal administration) is allowed.
- Have a history of generalized urticaria or angioedema, or of allergy, anaphylaxis, hypersensitivity or intolerance to a human or humanized antibody or to BNT351 excipients.
- Part B:
- Have received an HIV vaccination or HIV broadly neutralizing antibody in another clinical study.
- Are receiving ongoing therapy for Mycobacterium tuberculosis infection.
- Have a history of opportunistic infections/AIDS-defining illnesses as defined in the protocol.
- Have a history of multi-class drug resistant HIV-1 infection defined as resistance to three or more classes of HIV drugs.
- Have a known or suspected impairment/alteration of immune function or immunodeficiency (except for HIV infection), including receipt of any immunostimulant, immunomodulator, immunosuppressive medication, immunoglobulin, blood product, or oral or parenteral steroid within 60 days prior to Day 1 or planned administration during the study. The following exception applies: Use of inhaled, intranasal, topical, or locally injected corticosteroids (e.g., intraarticular or intrabursal administration) is allowed.
- Have a history of generalized urticaria or angioedema, or of allergy, anaphylaxis, hypersensitivity or intolerance to a human or humanized antibody or to BNT351 excipients
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- BioNTech SElead
Study Sites (3)
Johns Hopkins
Baltimore, Maryland, 21205-1832, United States
UK Köln
Cologne, 50937, Germany
CRS Mannheim
Mannheim, 68167, Germany
Study Officials
- STUDY DIRECTOR
BioNTech Response Person
BioNTech SE
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 1
- Allocation
- RANDOMIZED
- Masking
- QUADRUPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
- Purpose
- TREATMENT
- Intervention Model
- SEQUENTIAL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
January 30, 2026
First Posted
February 6, 2026
Study Start
February 9, 2026
Primary Completion (Estimated)
June 1, 2027
Study Completion (Estimated)
June 1, 2027
Last Updated
March 19, 2026
Record last verified: 2026-03
Data Sharing
- IPD Sharing
- Will not share