NCT06847321ClinicalTrials.gov

Study of LHP588 in Subjects With P. Gingivalis-Positive Alzheimer's Disease

A Randomized, Double-Blind, Placebo-Controlled Study of LHP588 in Subjects With P. Gingivalis-Positive Alzheimer's Disease

RecruitingTaking participants now, according to the registry record.

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In brief

Phase 2300 participants sought38 sites1 country

Registered in 1 registry

ClinicalTrials.govNCT06847321Open this record at ClinicalTrials.govSynced 5 days ago

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Trial information is shown as published by the registry, in its original language.

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How this study is set up

The points below are drawn from the public registry record for this study. Each one cites the field or sentence it came from. A dash (—) means the record does not state something — not that it is missing or wrong. Many well-run studies, especially small ones, leave some of these blank.

Not stated: Registered after enrolment began (about 9 days after the recorded start)First posted 2025-02-26; recorded start 2025-02-17
Present: Has a defined primary outcomeA primary outcome measure is listed in the record
Present: The primary outcome states a time frameThe primary outcome measure records a time frame
Present: Participants are randomly assignedAllocation is recorded as randomised
Present: Has a comparison groupThe record lists a placebo or comparator arm, or more than one study arm
Present: Uses blinding (masking)A masking level is recorded in the record
Not stated: An ethics committee is not stated in the registry recordThis registry's ingested record has no ethics-committee field
Not stated: Regulatory oversight (such as an IND or IDE) is not stated in the registry recordThis registry's ingested record has no regulatory-authorisation field
Not stated: A data monitoring committee is not stated in the registry recordThis registry's ingested record has no data-monitoring-committee fieldA data monitoring committee is not required for many smaller studies, and its absence here is not unusual.
Present: No cost to participants is mentioned in the recordChecked the summary, description and eligibility text; no cost-to-participant phrase found
Not stated: No other studies from this sponsor are in this databaseCounted from the lead sponsor named in the record (Lighthouse Pharmaceuticals, Inc.)
Not stated: No posted results from this sponsor are in this database yetBased on the sponsor’s studies in this database

The record lists 2 conditions.
Lead sponsor type recorded as: industry.
Intervention regulatory context: investigational, within a phased regulatory pathway.

These are facts from the public registry record, not a judgement about the study. Discuss any trial with your own doctor before taking part.

What these facts mean, and what to ask · ruleset v1

Trial stature

Three independent measures of this study, described from its registry record — not a recommendation about it. A rigorous study by investigators nobody has heard of is better evidence than a weak study led by a famous one. How these are scored.

Methodological rigourDEFINITIVE

A definitive-grade design for a phase 2 study, judged from its ClinicalTrials.gov record.

How this score is built

Randomised allocation20/20
Participants are randomly allocated between arms
Blinding20/20
Quadruple-blind
Control arm13/15
Placebo / sham control arm
Primary-outcome specificity10/10
Named primary outcome with a defined time frame
Endpoint type3/10
Surrogate or intermediate endpoint (conservative default)
Multi-centre8/8
Multi-centre: 39 sites
Data monitoring committee7/7
A data monitoring committee is in place
Prospective registration3/5
Registered within 30 days of the study start
Protocol / SAP posted0/5
No protocol or SAP posted to the registry

ScaleMEDIUM

A medium-sized study: 300 participants (target), run at 38 sites.

How this score is built

Enrolment24/40
300 participants (target)
Site count19/25
39 sites
Country count0/15
Single country
Planned duration9/10
Planned over about 50 months
Sponsor scale0/10
Lighthouse Pharmaceuticals, Inc. has led 1 trials in our corpus

Investigator standingUNKNOWN

We have no verifiable track record for the investigator named on this trial. That is common for early-career investigators and for records held outside ClinicalTrials.gov — it is not a negative signal.

How this score is built

Investigator standing0/100
No investigator recorded in the registry for this trial

These describe the registry record only, and today we hold ClinicalTrials.gov data. Absent fields lower a score, and absence often reflects registration practice rather than study quality. A high-stature trial is not necessarily safer or a better choice for you — enrolling in a large definitive trial can mean a higher chance of receiving placebo, while a small early-phase study may be the only route to a new therapy.

Summary

This study is to test LHP588 in persons who have mild to moderate Alzheimer's disease (AD) who have shown progressive mental decline in the last year and who have P. gingivalis (Pg) infection. P. gingivalis infection has been linked to the development of dementia. LHP588 is designed to target the P. gingivalis bacterium, to potentially help to halt or slow down the progression of AD and its symptoms. A saliva test will be done to determine P. gingivalis infection. Tests for AD include standard questionnaires such as MMSE and a blood test for pTau217. Treatment will be blinded, meaning the participant and the doctor will not know if the participant is receiving LHP588 or placebo. The total time for participation in the study may be up to 64 weeks. This includes a screening period (to ensure the participant is suitable for the study and the study is suitable for the participant) of up to 12 weeks, a treatment period of up to 48 weeks, and a safety follow-up period of 4 weeks after the last dose of the study drug to check the participant's overall health. Treatment is a once-a-day capsule. Caregiver participation is required. The study requires the participant to visit the study center (with the caregiver) at least 20 times within 64 weeks (this does not include any unplanned visits that may be recommended by the study doctor). In addition, the study doctor or clinic staff will contact the participant via phone at least 1 time.

This is a randomized, double-blind, placebo-controlled study that will assess the efficacy and safety of LHP588 in participants with evidence of P. gingivalis \[Pg\] infection and Alzheimer's Disease (AD) according to the National Institute on Aging-Alzheimer's Association (NIA-AA) research criteria. Enrolled participants must also have evidence of P. gingivalis infection as determined by polymerase chain reaction (PCR) of saliva oral rinse and clinical evidence of progressive cognitive decline in the last year. The participant should not have other conditions or brain imaging abnormalities that can explain the symptoms of dementia based on prior imaging and the screening magnetic resonance imaging (MRI). Due to the nature of AD, participants must identify a primary caregiver prior to enrollment in the study who will assist the participant with study participation and attend clinic visits. The study will consist of the following periods: 1) screening period of up to 12 weeks, 2) double-blind treatment period of 48 weeks (including a 2 week up-titration for the high dose arm), and 3) safety follow-up period of 4 weeks. The screening period will include at least two office visits during which eligibility will be verified. The first screening visit assessments will be limited to include the Mini-Mental State Examination (MMSE), saliva sample collection to assess Pg positivity, and pTau217 sample collection. The second screening visit will only be scheduled for participants with positive results of Pg infection and pTau217 test, and the rest of the screening procedures will be performed. Screening MRI will be performed as the last eligibility verification assessment. Participants who meet all eligibility criteria will be randomized in a 1:1:1 fashion to receive LHP588 25 mg, LHP588 50 mg, or placebo, orally, once daily (QD) in a fasted state (at least one hour before or two hours after a meal) for 48 weeks. Dosing should be done at approximately the same time each day. Blood samples for pharmacokinetics levels and biomarkers will be collected during selected visits. Evaluations will be conducted according to the schedule of assessments and will include: Medical history, physical examination, height, weight, saliva rinse for verification of Pg infection, blood for pharmacokinetic analysis, safely laboratory measures, electrocardiogram, and cognitive and functional scale assessments such as ADAS Cog, administered periodically. After completion of study treatment, participants will continue to be monitored for 4 weeks and will have a phone call to assess safety at Week 50 and will return for the Safety Follow-up Visit (Week 52).

Conditions

Alzheimer Disease
Alzheimer Disease Due to P. Gingivalis

Eligibility

Eligibility
Sex	All
Ages	55 Years – 80 Years
Healthy volunteers	No

Eligibility as written in the registry

Inclusion Criteria: * AD according to the National Institute on Aging-Alzheimer's Association criteria. * MMSE scores corresponding to mild and moderate AD. * Saliva rinse sample positive for P. gingivalis. * Plasma pTau217 above cutoff. * Subject and caregiver have provided full written informed consent. * Background symptomatic therapy with acetylcholinesterase inhibitors, and/or memantine, are allowed if the dose has been stable for 90 days and no changes are planned during the study. * Modified Hachinski score ≤4 at screening. Exclusion Criteria: * History of cancer requiring systemic therapy in last 5 years. * Evidence of a clinically significant, unstable cardiovascular, pulmonary, renal, hepatic, gastrointestinal, neurologic, or metabolic disease within 6 months prior to screening. * Unstable angina, uncompensated and/or symptomatic congestive heart failure (Grade 2 or higher on the New York Heart Association scale) or myocardial infarction within 6 months. * Acute or poorly controlled blood pressure \>180 mmHg systolic or \>100 mmHg diastolic at screening visit. * History or current evidence of major neurological or psychiatric illness such as schizophrenia, bipolar disorder, Parkinson's Disease, other. * Currently being treated with anti-amyloid beta antibodies or other disease-modifying treatments for dementia. * Other criteria in the Investigator's judgement that may interfere with the ability to participate in the study.

Eligibility in plain statements

This record's criteria have not been broken into separate statements yet. The registry text above is complete and is the authoritative version.

Study design

Study design
Study type	Interventional
Phase	Phase 2
Allocation	Randomised
Intervention model	PARALLEL
Primary purpose	TREATMENT
Masking	QUADRUPLE (4)
Enrolment	300 participants sought

Sponsor and collaborators

Lighthouse Pharmaceuticals, Inc. Sponsor

Arms and interventions

PlaceboPLACEBO_COMPARATOR
Two (2) placebo capsules, once daily, for 48 weeks
LHP588 25 mgEXPERIMENTAL
One (1) 25 mg capsule and one (1) placebo capsule, once daily, for 48 weeks
LHP588 50 mgEXPERIMENTAL
Two (2) 25 mg capsules, once daily, for 48 weeks

Interventions

Drug LHP588
25 mg, once daily
Drug LHP588
50 mg, once daily
Drug Placebo Drug
Placebo, once daily

Outcome measures

Primary outcome
Change in ADAS-Cog11
ADAS-COG11 is the Alzheimer's Disease Assessment Scale-Cognitive Subscale 11
Time frame 40 - 48 weeks
Secondary outcome
Change in ADCS-ADL
ADCS-ADL is the Alzheimer's Disease Cooperative Study Group-Activities of Daily Living
Time frame 40 - 48 weeks
Secondary outcome
Change in CMAI
CMAI is the Cohen-Mansfield Agitation Inventory
Time frame 40 - 48 weeks
Secondary outcome
Change in CDR-SB
CDR-SB is the Clinical Dementia Rating-Sum of Boxes
Time frame 40 - 48 weeks

Dates

Dates
Start date	February 17, 2025 (actual)
Primary completion	January 31, 2029 (estimated)
Completion	March 15, 2029 (estimated)
First posted	February 26, 2025 (actual)
Last updated	September 15, 2026
Results posted	Not stated in the registry record
Status last verified	June 2026

Actual means the event happened. Estimated means the sponsor expects it. The two mean different things.

Locations

37 sites are recruiting

United States

United States
Facility	City	State or region	Status
Alzheimer's Disease Research Center	Albany	New York	Recruiting
IMA Evaluations	Albuquerque	New Mexico	Recruiting
JEM Research Institute	Atlantis	Florida	Recruiting
Northwest Clinical Research Center	Bellevue	Washington	Recruiting
Adams Clinical Boston	Boston	Massachusetts	Recruiting
University of Virginia Adult Neurology	Charlottesville	Virginia	Recruiting
Clinical Research Professionals - Headlands	Chesterfield	Missouri	Recruiting
Columbus Memory Center	Columbus	Georgia	Recruiting
Kerwin Research Center, LLC - Oak Cliff	Dallas	Texas	Recruiting
Kerwin Research Center, LLC in Texas	Dallas	Texas	Recruiting
NDx Clinical Research	Dayton	Ohio	Recruiting
Brain Matters Research	Delray Beach	Florida	Recruiting
CenExel Denver, CO	Englewood	Colorado	Recruiting
Re-Cognition Health Fairfax	Fairfax	Virginia	Recruiting
Neuropsychiatric Research Center of Southwest Florida	Fort Myers	Florida	Recruiting
Center for Advanced Research & Education Flourish-Gainesville	Gainsville	Georgia	Recruiting
Neurological Research Center - Hattiesburg Clinic	Hattiesburg	Mississippi	Recruiting
Tandem Clinical Research - Metairie	Metairie	Louisiana	Recruiting
K2 Medical Research Nashville LLC	Nashville	Tennessee	Recruiting
Adams Clinic Harlem	New York	New York	Recruiting
Oakland Clinical Research	Oakland	California	Recruiting
ATP Clinical Research, Inc.	Orange	California	Recruiting
Conquest Research - Lake Nona	Orlando	Florida	Recruiting
Anchor Neuroscience	Pensacola	Florida	Active, not recruiting
Barrow Neurological Institute	Phoenix	Arizona	Recruiting
Banner Alzheimer's Institute	Phoenix	Arizona	Recruiting
Headlands PharmaSite	Pikesville	Maryland	Recruiting
Headlands Research-EMA	Plymouth	Massachusetts	Recruiting
Progressive Medical Research	Port Orange	Florida	Recruiting
Summitt Research	Portland	Oregon	Recruiting
Riverside Clinical Research	Riverside	California	Recruiting
Clinical Endpoints	Scottsdale	Arizona	Recruiting
CenExel Sherman Oaks	Sherman Oaks	California	Recruiting
Alzheimer's Research and Treatment Center - Stuart	Stuart	Florida	Recruiting
CenExel Research - Toms River	Toms River	New Jersey	Recruiting
Adams Clinical Watertown	Watertown	Massachusetts	Recruiting
Alzheimer's Research and Treatment Center - Wellington	Wellington	Florida	Recruiting
Ascension via Christi Research	Wichita	Kansas	Recruiting

Study documents

No documents are linked in this registry record.

Changes over time

September 15, 2026
Site removed
1 site removed (38 total)
3938
September 8, 2026
Site removed
1 site removed (39 total)
4039
July 31, 2026
Site added
1 site added (40 total)
3940

Registry: ClinicalTrials.gov · NCT########

https://xmedica.io/trials/ctgov/NCT06847321

Categories

Registered in 1 registry

Interested in this study?

How this study is set up

Summary

Conditions

Eligibility

Eligibility as written in the registry

Eligibility in plain statements

Study design

Sponsor and collaborators

Arms and interventions

Interventions

Outcome measures

Dates

Locations

United States

Study documents

Changes over time