HIV-1-infectionPhase 2/3NCT05271370

An Extension Protocol for Virologically Suppressed Subjects Who Successfully Completed PRO140_CD03 Study

A Phase 2/3 study testing PRO 140 350, PRO 140 525 and PRO 140 700 in people with HIV-1-infection, run by CytoDyn, Inc. at 1 site in United States.

Terminated

Stopped early. The study ended before it was planned to and will not resume.

Official record

Search all trials

Trial summary

This study is a Phase 2b/3 multi-center extension study designed to evaluate the long term antiviral activity, safety, and tolerability of the strategy of continuing PRO 140 350mg, 525mg, or 700mg SC (subcutaneous) monotherapy to maintain viral suppression after initial 48 weeks in virologically suppressed subjects. Read more about this study

Who is it for?: Ages 18 years and older
Conditions the study is for: HIV-1-infection
What is being tested?: PRO 140 350, PRO 140 525 and PRO 140 700
Type of treatment: Injection or infusion
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 56 participants
Where: 1 siteUnited States
Study dates: 29 Aug 2017to 10 Jul 2022
Phase: Phase 2/3
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 years and older
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Subjects who have completed 48 weeks of treatment in PRO140_CD03 study.
Last known Plasma HIV-1 RNA < 50 copies/mL within PRO140_CD03 study.
Both male and female patients and their partners of childbearing potential must agree to use 2 medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], and intrauterine devices) during the course of the study (excluding women who are not of childbearing potential and men who have been sterilized). Females of childbearing potential must have a negative serum pregnancy test at Screening visit and negative urine pregnancy test prior to receiving the first dose of study drug.
Willing and able to participate in all aspects of the study, including use of SC medication, completion of subjective evaluations, attendance at scheduled clinic visits, and compliance with all protocol requirements as evidenced by providing written informed consent.

Who cannot join

Not currently enrolled in PRO140_CD03 study.
Any active infection or malignancy requiring acute therapy (with the exception of local cutaneous Kaposi's sarcoma).
Females who are pregnant, lactating, or breastfeeding, or who plan to become pregnant during the study.
Subjects weighing < 35kg.
History of anaphylaxis to any oral or parenteral drugs.
History of Bleeding Disorder or patients on anti-coagulant therapy (except aspirin).
Note: Subjects with well-controlled bleeding disorder while on stable anti-coagulant therapy dose with documented stable INRs can be enrolled as per discretion of the Investigator.
Any other clinical condition that, in the Investigator's judgment, would potentially compromise study compliance or the ability to evaluate safety/efficacy.

Trial locations and contacts

1 site in 1 country.

United States1 site

Quest Clinical Research
San Francisco, California, 94115

Other trials in United States

About this study

Consenting subjects will continue weekly PRO 140 350mg, 525mg, or 700mg monotherapy during the Treatment Extension Phase with the one-week overlap of existing retroviral regimen and PRO 140 350mg, 525mg, or 700 mg at the end of the treatment in subjects who do not experience virologic failure.

Read the detailed description

The objective is to assess the long-term safety of using PRO 140 350mg, 525mg, or 700mg SC as single-agent maintenance therapy for the chronic suppression of CCR5-tropic HIV-1 infection.

Conditions: HIV-1-infection
Being tested: PRO 140 350, PRO 140 525, PRO 140 700

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

PRO 140 350Drug
Also called leronlimab
Pro140 SC injection 350 mg
PRO 140 525Drug
Also called leronlimab
525 mg
PRO 140 700Drug
Also called leronlimab
700 mg

Study groups in NCT05271370
Study group	Role	What they receive
PRO 140 350 mg	Experimental	PRO 140 350mg weekly SC injection. Receives: Drug: PRO 140 350
PRO 140 525 mg	Experimental	PRO 140 525mg weekly SC injection. Receives: Drug: PRO 140 525
PRO 140 700 mg	Experimental	PRO 140 700mg weekly SC injection. Receives: Drug: PRO 140 700

What is being measured

The primary outcome is the main question the study is designed to answer.

Long Term Clinical Safety of PRO 140 Monotherapy by Assessing the Number of Participants With Grade 2, 3 or 4 Adverse Events as Defined by the DAIDS Adverse Event Scale, and the Number of Participants With Treatment-emergent Serious Adverse Events.
The Division of AIDS (DAIDS) grading table provides an adverse event severity grading scale ranging from grades 1 to 5 with descriptions for each adverse event based on the following general guidelines:
- Grade 1 indicates a mild event
- Grade 2 indicates a moderate event
- Grade 3 indicates a severe event
- Grade 4 indicates a potentially life-threatening event
- Grade 5 indicates death (Note: This grade is not specifically listed on each page of the grading table). Treatment-Emergent Serious Adverse Events (TESAEs) are defined as serious adverse events with an onset on or after the first treatment.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Proportion of Participants Experiencing Virologic Failure for All Subjects Within Each Treatment Group.
Virological failure is defined as two consecutive HIV-1 RNA levels of ≥ 200 copies/mL for all subjects and within each treatment group.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks

Secondary outcomes (5)

Time to Virologic Failure After Initiating PRO 140 Monotherapy for All Subjects Within Each Treatment Group.
Virological failure (VF) is defined as two consecutive HIV-1 RNA levels of ≥ 200 copies/mL for all subjects and within each treatment group. The date of VF event is defined as the date of the second assessment of the two (2) consecutive HIV-1 RNA levels of >= 200 copies/mL when virological failure is confirmed. Subjects who did not have VF, the last visit date will be used as the date of the event.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Proportion of Participants Achieving Viral Re-suppression After Experiencing Virologic Failure Within Each Treatment Group.
Viral re-suppression is defined as having HIV-1 RNA levels of < 50 copies/mL after experiencing virologic failure within each treatment group.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Time to Achieving Viral Re-suppression After Experiencing Virologic Failure Within Each Treatment Group.
Viral re-suppression is defined as having HIV-1 RNA levels of < 50 copies/mL after experiencing virologic failure within each treatment group.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Proportion of Virologic Failure Subjects Achieving Viral Re-suppression With Re-initiation of Previous Baseline Antiretroviral Regimen Within Each Treatment Group.
Viral re-suppression is defined as having HIV-1 RNA levels of < 50 copies/mL after experiencing virologic failure within each treatment group. Subjects who experienced virologic failure during the treatment phase had an option to re-initiate their PRO 140 regimen to their previous baseline or dose escalate to the next dose level.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Mean Change in CD4 Cell Count, at Each Visit Within the Treatment Phase for All Subjects Within Each Treatment Group
The change from baseline in CD4 cell count was summarized for each visit during the treatment phase for each treatment group. The time-weighted mean of change of the post baseline (visit TE1) values was calculated. The time-weighted mean was adjusted AUC (area under the curve) by time.
Measured: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

29 Aug 201710 Jul 2022

First posted9 Mar 2022
Study start29 Aug 2017
Primary completion20 Jun 2022
Study completion10 Jul 2022

Why it stopped: FDA required the sponsor to halt enrollment in the trial and transition participants to available therapies for the treatment of their disease. The trial was subsequently terminated once participants were transitioned.

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Other trials for HIV-1-infectionStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 2/3
Primary purpose: Treatment
Allocation: Non-randomised
Intervention model: Parallel groups
Model description: Open Label
Masking: None (open label)
Enrolment: 56 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT05271370
Sponsor's protocol ID: PRO 140_CD03 Extension
Status last verified: Oct 2025
First submitted: 13 Jan 2022
Last updated: 30 Oct 2025
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: No

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

RecruitingObservational study
Cohort of Women Living With HIV-1 and Receiving Bictegravir/Emtricitabine/Tenofovir Alafenamide
HIV (Human Immunodeficiency Virus), Pregnancy
RecruitingPhase 4
A Study to Provide Continued Access to Study Drug to Children and Adolescents Who Have Completed Clinical Studies Involving Gilead HIV Treatments
HIV-1-infection
RecruitingObservational study
Leukapheresis Procedures to Obtain Plasma and Lymphocytes for Research Studies on Antiretroviral Naive HIV-1 Research Participants
HIV
Active, not recruitingPhase 3
Study to Compare Bictegravir/Lenacapavir Versus Current Therapy in People With HIV-1 Who Are Successfully Treated With Biktarvy
HIV-1-infection
Active, not recruitingPhase 2/3
Study to Compare Bictegravir/Lenacapavir Versus Current Therapy in People With HIV-1 Who Are Successfully Treated With a Complicated Regimen (ARTISTRY-1)
HIV-1-infection

All HIV-1-infection trials

Study at a glance

From the registry record, last updated by the sponsor on 30 Oct 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: An Extension Protocol for Virologically Suppressed Subjects Who Successfully Completed PRO140_CD03 Study
ClinicalTrials.gov ID: NCT05271370
Acronym / sponsor ID: PRO 140_CD03 Extension
Conditions: HIV-1-infection
Phase: Phase 2/3
Study type: Interventional
Recruitment status: TerminatedReason stopped: FDA required the sponsor to halt enrollment in the trial and transition participants to available therapies for the treatment of their disease. The trial was subsequently terminated once participants were transitioned.
Enrolment: 56 participants (actual)
Lead sponsor: CytoDyn, Inc.Industry (pharma, biotech, devices)
Study start: 29 Aug 2017 (actual)
Primary completion: 20 Jun 2022 (actual)
Study completion: 10 Jul 2022 (actual)
First posted: 9 Mar 2022 (actual)
Results: Posted 30 Oct 2025

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

The objective is to assess the long-term safety of using PRO 140 350mg, 525mg, or 700mg SC as single-agent maintenance therapy for the chronic suppression of CCR5-tropic HIV-1 infection.

Study design

Primary purpose: Treatment
Allocation: Non-randomised
Intervention model: Parallel groups
Masking: None (open label)
Number of arms: 3
Model description: Open Label

Arm	Type	Receives
PRO 140 350 mg	Experimental	Drug: PRO 140 350PRO 140 350mg weekly SC injection.
PRO 140 525 mg	Experimental	Drug: PRO 140 525PRO 140 525mg weekly SC injection.
PRO 140 700 mg	Experimental	Drug: PRO 140 700PRO 140 700mg weekly SC injection.

Who may qualify

Ages: 18 years and older
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (4 listed)

Subjects who have completed 48 weeks of treatment in PRO140_CD03 study.
Last known Plasma HIV-1 RNA < 50 copies/mL within PRO140_CD03 study.
Both male and female patients and their partners of childbearing potential must agree to use 2 medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], and intrauterine devices) during the course of the study (excluding women who are not of childbearing potential and men who have been sterilized). Females of childbearing potential must have a negative serum pregnancy test at Screening visit and negative urine pregnancy test prior to receiving the first dose of study drug.
Willing and able to participate in all aspects of the study, including use of SC medication, completion of subjective evaluations, attendance at scheduled clinic visits, and compliance with all protocol requirements as evidenced by providing written informed consent.

Key exclusion criteria (8 listed)

Not currently enrolled in PRO140_CD03 study.
Any active infection or malignancy requiring acute therapy (with the exception of local cutaneous Kaposi's sarcoma).
Females who are pregnant, lactating, or breastfeeding, or who plan to become pregnant during the study.
Subjects weighing < 35kg.
History of anaphylaxis to any oral or parenteral drugs.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
PRO 140 350Also: leronlimabPro140 SC injection 350 mg	Drug	PRO 140 350 mg
PRO 140 525Also: leronlimab525 mg	Drug	PRO 140 525 mg
PRO 140 700Also: leronlimab700 mg	Drug	PRO 140 700 mg

Primary outcome

Long Term Clinical Safety of PRO 140 Monotherapy by Assessing the Number of Participants With Grade 2, 3 or 4 Adverse Events as Defined by the DAIDS Adverse Event Scale, and the Number of Participants With Treatment-emergent Serious Adverse Events.
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
The Division of AIDS (DAIDS) grading table provides an adverse event severity grading scale ranging from grades 1 to 5 with descriptions for each adverse event based on the following general guidelines: * Grade 1 indicates a mild event * Grade 2 indicates a moderate event * Grade 3 indicates a severe event * Grade 4 indicates a potentially life-threatening event * Grade 5 indicates death (Note: This grade is not specifically listed on each page of the grading table). Treatment-Emergent Serious Adverse Events (TESAEs) are defined as serious adverse events with an onset on or after the first treatment.
Proportion of Participants Experiencing Virologic Failure for All Subjects Within Each Treatment Group.
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Virological failure is defined as two consecutive HIV-1 RNA levels of ≥ 200 copies/mL for all subjects and within each treatment group.

5 secondary outcomes

Time to Virologic Failure After Initiating PRO 140 Monotherapy for All Subjects Within Each Treatment Group.
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Proportion of Participants Achieving Viral Re-suppression After Experiencing Virologic Failure Within Each Treatment Group.
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Time to Achieving Viral Re-suppression After Experiencing Virologic Failure Within Each Treatment Group.
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Proportion of Virologic Failure Subjects Achieving Viral Re-suppression With Re-initiation of Previous Baseline Antiretroviral Regimen Within Each Treatment Group.
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks
Mean Change in CD4 Cell Count, at Each Visit Within the Treatment Phase for All Subjects Within Each Treatment Group
Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks

Results and safety

Results posted to the registry on 30 Oct 2025, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
PRO 140 350 mg	8	0
PRO 140 525 mg	18	2
PRO 140 700 mg	30	1

Primary outcome: Long Term Clinical Safety of PRO 140 Monotherapy by Assessing the Number of Participants With Grade 2, 3 or 4 Adverse Events as Defined by the DAIDS Adverse Event Scale, and the Number of Participants With Treatment-emergent Serious Adverse Events.

Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks. Number. Unit: participants

Measure	PRO 140 350 mg n = 8	PRO 140 525 mg n = 18	PRO 140 700 mg n = 30
Participants with Grade 2, 3, or 4 AEs	5	6	6
Participants with TESAEs	3	5	2

Population analysed: The safety population is defined as all subjects who received at least one dose of PRO 140 within the PRO 140\_CD03 extension study.

Primary outcome: Proportion of Participants Experiencing Virologic Failure for All Subjects Within Each Treatment Group.

Time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks. Number. Unit: proportion of participants

Measure	PRO 140 350 mg n = 8	PRO 140 525 mg n = 18	PRO 140 700 mg n = 30
Value	0	0.17	0.37

Population analysed: The analysis population is defined as all subjects who enrolled in the study and received at least one dose of PRO 140.

5 secondary outcomes are reported in the full results.

Adverse events

Time frame: Report initiation for all adverse events began at the time of the first treatment extension visit and continued up until the final study visit (up to approximately 197 weeks).. Other adverse events reported at 5% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
PRO 140 350 mg	3 of 8 (37.5%)	6 of 8 (75%)	1 of 8
PRO 140 525 mg	5 of 18 (27.8%)	9 of 18 (50%)	1 of 18
PRO 140 700 mg	2 of 30 (6.7%)	18 of 30 (60%)	0 of 30

Limitations and caveats (from the sponsor): FDA required the sponsor to halt enrollment in the trial and transition participants to available therapies for the treatment of their disease. The trial was subsequently terminated once participants were transitioned.

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 30 Oct 2025.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Individual participant dataSharing planned: No

Related trials for HIV-1-infection

RecruitingObservational study
Cohort of Women Living With HIV-1 and Receiving Bictegravir/Emtricitabine/Tenofovir Alafenamide
HIV (Human Immunodeficiency Virus), Pregnancy
RecruitingPhase 4
A Study to Provide Continued Access to Study Drug to Children and Adolescents Who Have Completed Clinical Studies Involving Gilead HIV Treatments
HIV-1-infection
RecruitingObservational study
Leukapheresis Procedures to Obtain Plasma and Lymphocytes for Research Studies on Antiretroviral Naive HIV-1 Research Participants
HIV
Active, not recruitingPhase 3
Study to Compare Bictegravir/Lenacapavir Versus Current Therapy in People With HIV-1 Who Are Successfully Treated With Biktarvy
HIV-1-infection
Active, not recruitingPhase 2/3
Study to Compare Bictegravir/Lenacapavir Versus Current Therapy in People With HIV-1 Who Are Successfully Treated With a Complicated Regimen (ARTISTRY-1)
HIV-1-infection

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Jacob Lalezari, MD principal investigator

CytoDyn, Inc.

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 2/3 study testing PRO 140 350, PRO 140 525 and PRO 140 700 in people with HIV-1-infection, run by CytoDyn, Inc. at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: stopped early, as of the sponsor's last update on 30 Oct 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this combined phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 30 Oct 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Long Term Clinical Safety of PRO 140 Monotherapy by Assessing the Number of Participants With Grade 2, 3 or 4 Adverse Events as Defined by the DAIDS Adverse Event Scale, and the Number of Participants With Treatment-emergent Serious Adverse Events. (time frame: From TE1 (first treatment administration) to last treatment visit, up to 197 weeks). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05271370.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 30 Oct 2025.