A Phase 1 interventional study of Emtricitabine and tenofovir disoproxil fumarate combination and Placebo in Alzheimer's Disease, sponsored by Brigham and Women's Hospital. Not yet recruiting at 1 site in United States. Open to participants aged 55 Years to 85 Years. Per ClinicalTrials.gov, last updated 2026-08-31.
Sponsored by Brigham and Women's Hospital · Phase 1, Interventional, and Treatment
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Among 11 studies in Alzheimer Disease by Brigham and Women's Hospital — 3 open to participants now, 3 under way, none of them phase 3. Alzheimer Disease · Brigham and Women's Hospital.
Among the 11 studies in Alzheimer Disease by Brigham and Women's Hospital, this one is the 8th largest by planned enrollment, is the only one that started in 2026, is one of 2 in phase 1, and was the 11th registered.
3,968 studies on the registry are indexed under Alzheimer Disease; 928 are open to participants now.
Browse Alzheimer Disease studies →3 of the 11 studies in Alzheimer Disease by Brigham and Women's Hospital are open now, in 1 country. Recruiting first, the newest first:
Brigham and Women's Hospital · Sites in United States
Ages 60–85
Brigham and Women's Hospital · Sites in United States
Ages 18–85 · Healthy volunteers
By country, each count listing its studies:
Of the 643 Alzheimer Disease studies recruiting now, 284 (44%) set no upper age limit and 55 (9%) stop at 75 or younger; 34 take children under 18; 285 take healthy volunteers.
This study: 55 Years to 85 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
11 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 5 · Phase 2 4
First in 2007; this study’s year is marked. 1 started in 2026.
By drug class, each counting the studies that test any of its medicines:
This study's planned enrollment of 20 is below the median of 70 across 3,021 interventional studies indexed under Alzheimer Disease.
Median enrollment 40 across the 11 interventional studies. Of the 8 that completed or were terminated, 4 (50%) have results posted.
This tab as a report to print or save as PDF → With an account.
Brigham and Women's Hospital is the lead sponsor of 1,268 studies on the registry; 229 are open to participants now.
Of its 116 completed or terminated interventional studies of FDA-regulated products, 65 (56%) have results posted.
None of the studies under way reaches primary completion within a year.
Among the 11 studies in Alzheimer Disease by Brigham and Women's Hospital, from their registry updates:
Nothing recorded among them since 2026-09-25.
This tab as a report to print or save as PDF → With an account.
The goal of this clinical trial is to determine the safety, tolerability, drug levels and biological effects of two doses of emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) combination administered daily for 4 weeks in older adults with early Alzheimer's disease. The main questions it aims to answer are:
Researchers will compare two doses of FTC-TDF combination to a placebo (a look-alike substance that contains no drug) to see if FTC-TDF combination is safe in older adults who have early Alzheimer's disease.
Participants will:
Objectives:
To conduct a phase 1b trial to determine the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of multiple ascending doses of emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) combination administered daily for 4 weeks in older adults with early Alzheimer's disease (AD).
Primary:
1) To evaluate safety and tolerability, we will conduct structured monitoring of adverse events (AEs) and serious AEs (SAEs). Additionally, we will perform safety laboratory tests including blood counts and chemistries, coagulation profile, physical exams, vital signs, and electrocardiogram (ECG).
Secondary:
Study Design/ Methodology:
This is a phase 1b, single-center, placebo-controlled, multiple ascending dose study of 20 participants with early AD.
The intervention duration is 28 days. Please see the Schedule of Events table.
There will be a single performance site for the clinical trial at the Center for Alzheimer Research and Treatment (CART) at Brigham and Women's Hospital (BWH).
Starting on day 0, the study participants will be randomized to either placebo or active drug (two dose strengths). The participants will take the study drug orally once daily for 28 days.
Questionnaires will be administered at screening (Clinical Dementia Rating [CDR], Mini-Mental State Exam [MMSE], Logical Memory, 15-item Geriatric Depression Scale [GDS], and Columbia-Suicide Severity Rating Scale [C-SSRS]), which will last up to 45 days.
Number of Participants:
A total of 20 participants will be enrolled in this trial. Participants discontinued from study for any reason or lost-to-follow up before completing the study will be replaced.
Investigational Product, Dosage and Mode of Administration:
Product: FTC and TDF combination tablets at two dose strengths that are in clinical use: 133 mg FTC plus 200 mg TDF, and 200 mg FTC plus 300 mg TDF.
Dosing Cohort: Two dosing cohorts of 10 participants each will be studied successively in ascending order. The first cohort of 10 participants will receive either one tablet of FTC (133 mg) and TDF (200 mg) combination once daily (n=7), or one placebo tablet daily (n=3) for 28 consecutive days. The second cohort of 10 participants will receive either one tablet of FTC (200 mg) and TDF (300 mg) combination once daily (n=7) or one placebo tablet once daily (n=3) for 28 consecutive days.
Duration of Treatment:
Participants will take FTC and TDF combination or placebo tablets once daily for 28 days.
Reference Therapy, Dosage and Mode of Administration:
Placebo tablets once daily for 28 days.
Statistical Methods:
Statistical Power and Sample Size Estimation:
By convention, the sample size of 10 participants per dose group (7 active, 3 placebo) is considered sufficient for evaluation of safety, tolerability, PK, and PD. In previous PK studies of FTC and TDF in adults without HIV infection, the changes from baseline in the plasma concentrations of these drugs were large (>2 standard deviation [SD]); the proposed sample size will provide >80% power to detect changes of similar magnitude in this phase 1b trial. All P values will be considered nominal.
Statistical Analyses:
Safety Analysis: Safety assessments will be based on AE reports and the results of vital signs, ECGs, physical examinations, and laboratory tests, with particular attention to gastrointestinal symptoms, transaminases, creatinine and eGFR, glycosuria, hypophosphatemia, amylase, and lipase. All AEs will be coded and summarized by system organ class (SOC), and preferred term using Medical Dictionary for Regulatory Activities (MedDRA), and Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.
Changes in laboratory measures from baseline to final visit will be compared across groups using mixed-model repeated measures regression (MMRM) with treatment, visit, treatment-by-visit interaction and baseline value adjusted for sex. Shift tables will be generated for the ECG changes from baseline to the post dose by dose groups. Relationship between dose level (linear and discrete) and safety data (change from baseline) will be explored by mixed-effects regression model. Estimates and 95% confidence intervals (CIs) extracted from this model will also be provided. Type 1 error will be set at 0.05, no adjustment will be made for multiplicity, and results will be reported as relative risks and corresponding 95% CIs. In addition to the frequency of AEs, the seriousness and nature of AEs will be considered.
PK Analysis: The PK parameters will be calculated from TDF and FTC plasma concentrations and will include maximum and minimum concentration (Cmax, Cmin), time of the maximum concentration (tmax), area under the concentration curve (AUC) over 24 hours (AUC0-24h), average steady-state concentration (Cssave), AUC from the time of dosing to the last measurable concentration (AUC0-tlast), AUC extrapolated to infinity (AUC0-∞) (where estimable), and terminal phase half-life (t1/2). PK modeling will utilize the Phoenix WinNonlin for non-compartmental analysis, widely considered the industry standard and accepted by the FDA. The following conventions will be utilized: 1) for initial time points, concentrations below the lowest limit of quantification (LLOQ) will be treated as "zero", embedded and/or termination concentrations below the LLOQ are not expected in our assay, but, if observed, will be treated as missing.
Standard single and multiple dose PK parameters will be summarized by dose group using descriptive statistics. Geometric means and coefficients of variation will be presented for Cmax, AUC0-24h, AUClast, and AUCinf. Median and ranges will be presented for Tmax. Means and standard deviations will be provided for the other PK parameters. Dose proportionality will be analyzed using linear regression adjusting for baseline values. Cssave will be compared with historical values from healthy control participants receiving the standard FTC-TDF dose where the same assay and procedures were used.
PD Analysis: Only participants with available baseline values and at least one post-dose value for PD parameters will be included in the change from baseline analyses. The changes from baseline over the 28-day treatment period in the PBMC TDF-DP and FTC-TP concentrations, normalized by DNA content, by dose group will be compared using MMRM with treatment, visit, treatment-by-visit interaction adjusted for baseline. An unstructured covariance matrix will be used to account for intra-individual serial correlation of measures. If unstructured covariance structure matrix results in a lack of convergence, a compound symmetry covariance structure will be employed. The same MMRM approach will be used for the analyses of the change in reverse transcriptase activity in the PBMCs.
PD assessments will be summarized using descriptive statistics for each dose and time point. PD effects will be evaluated in relation to the TDF-DP and FTC-TP exposure (Cssave) by participant and/or by group according to dose level. Time course of PD effects will be plotted.
PK/PD Analysis: Relation between dose level and PK parameters will be analyzed using linear regression models. Estimates and 95% CIs extracted from this model will be employed to assess magnitude of the association. In addition to the PD analysis above, a population PK-PD model will be developed to describe the time course and relation of plasma and TDF-DP and FTC-TP concentrations and PD markers.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
MMSE and MoCA
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
DSM diagnostic criteria
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
FTC and TDF combination tablets at two dose strengths that are in clinical use: 133 mg FTC plus 200 mg TDF, and 200 mg FTC plus 300 mg TDF. There is a 70% chance participants will receive the FTC-TDF combination.
Drug: Emtricitabine and tenofovir disoproxil fumarate combination
Placebo tablets. There is a 30% chance participants will receive placebo.
Drug: Placebo
Drug pages: Emtricitabine · Tenofovir
FTC and TDF combination tablets at two dose strengths that are in clinical use: 133 mg FTC plus 200 mg TDF, and 200 mg FTC plus 300 mg TDF.
Placebo tablets.
Safety and tolerability
Treatment-emergent adverse events (AEs).
Time frame: 28 days
Safety and tolerability
Treatment-emergent serious AEs (SAEs)
Time frame: 28 days
Safety and tolerability
Changes in clinical laboratory tests. Specifically, will report the number of participants with abnormal laboratory values and/or AEs that are related to treatment.
Time frame: 28 days
Safety and tolerability
Changes in blood pressure (systolic and diastolic)
Time frame: 28 days
Safety and tolerability
Changes in physical exams. Specifically, this will reflect new or worsening findings on a general physical exam and a neurological exam performed by a study physician.
Time frame: 28 days
Safety and tolerability
Clinical findings of 12-lead electrocardiograms (ECGs). Specifically, change in QTc interval.
Time frame: 28 days
Safety and tolerability
Changes in pulse
Time frame: 28 days
Pharmacokinetics (PK) Concentration average
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (Concentration average 0-24 hours)
Time frame: 28 days
Pharmacodynamics (PD)
PD endpoint: steady-state serum concentration of active metabolites (TBP and ETP) in PBMCs pre-dose and at 4 and 8 hours after administration of study drug on days 0 and 28.
Time frame: 28 days
Activity of reverse transcriptase
LINE-1 in PBMCs on days 0 and 28.
Time frame: 28 days
Markers of systemic inflammation
hsCRP, IL-6, and TNF alpha on days 0, 14, and 28.
Time frame: 28 days
Pharmacokinetics (PK) Concentration maximum
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (Concentration maximum).
Time frame: 28 days
Pharmacokinetics (PK) T max
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (Time to reach maximum concentration \[Tmax\]).
Time frame: 28 days
Pharmacokinetics (PK) lambda z
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (apparent terminal elimination rate constant \[lambda z\])
Time frame: 28 days
Pharmacokinetics (PK) AUC last
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (Area Under the Curve to the last quantifiable time-point \[AUC last\]).
Time frame: 28 days
Pharmacokinetics (PK) AUC 24 hours
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (Area Under the Curve for 24 hours \[AUC 24hr\]).
Time frame: 28 days
Pharmacokinetics (PK) T 1/2
PK of two ascending dose regimens of FTC-TDF combination: circulating drug levels pre-dose and at 0.5, 1, 2, 4, 8, and 24 hours on Days 0 and 28; single nadir blood samples on days 3, 7, and 14 approximately 24 hours following the previous dose; single and multiple dose PK parameters calculated using nonparametric methods on days 0 and 28 (half-life \[T 1/2\]).
Time frame: 28 days
Plan to share: Yes — All de-identified data will be made available for sharing with other non-profit entities for non-commercial, legitimate scientific reasons upon appropriate request.
Start is estimated for Dec 2026; primary completion for Jul 2028, 19 months later.
Of 73 non-industry phase 1 interventional studies under Alzheimer Disease, half reached primary completion within 44 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 57. This study's planned 19 months is below that.
Counting every sponsor, half of 234 studies reached it within 18 months; a quarter within 7 and three quarters within 39.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drugs tested here: Emtricitabine · Tenofovir
Brigham and Women's Hospital →