Recruiting
Phase 2

LHP588

Sponsor:

Lighthouse Pharmaceuticals, Inc.

Code:

NCT06847321

Conditions

Alzheimer Disease

Alzheimer Disease Due to P. Gingivalis

Eligibility Criteria

Sex: All

Age: 55 - 70+

Healthy Volunteers: Not accepted

Interventions

LHP588

LHP588

Placebo Drug

Study Details

Brief 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.

Conditions

Alzheimer Disease

Alzheimer Disease Due to P. Gingivalis

Study ID

NCT06847321

Start date

Feb 17, 2025

Status verified date

Jun, 2026

Completion date

Mar 15, 2029

Anticipated

Primary completion date

Jan 31, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 55 - 70+

Healthy Volunteers: Not accepted

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.

Study Design

Enrollment

300 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

placebo comparator: Placebo

Two (2) placebo capsules, once daily, for 48 weeks

experimental: LHP588 25 mg

One (1) 25 mg capsule and one (1) placebo capsule, once daily, for 48 weeks

experimental: LHP588 50 mg

Two (2) 25 mg capsules, once daily, for 48 weeks

Interventions

LHP588

25 mg, once daily

LHP588

50 mg, once daily

Placebo Drug

Placebo, once daily

Primary outcome measure

  • Change in ADAS-Cog11 [ Time Frame: 40 - 48 weeks ]

Central Contacts and Locations

Central contacts

Joanna Bolger

858-248-5124jbolger@lighthousepharma.com

Locations

Banner Alzheimer's Institute

Recruiting

Phoenix, Arizona, United States, 85006

Contacts

Laura Martinez, SCRC

602-839-6500BannerAlzResearch@bannerhealth.com

Principal Investigator:

Allison Perrin, MD

Barrow Neurological Institute

Recruiting

Phoenix, Arizona, United States, 85013

Contacts

Margeaux Snell, MD, CCRC

602-406-3378Margeaux.snell@commonspirit.org

Principal Investigator:

Anna Burke, MD

Clinical Endpoints

Recruiting

Scottsdale, Arizona, United States, 85258

Contacts

Jenna Leger

480-566-9090jleger@clinicalendpoints.com

Principal Investigator:

Allan Block, MD

Oakland Clinical Research

Recruiting

Oakland, California, United States, 94609

Contacts

Crystal Huynh

510-817-2000crystal@irvineclinical.com

Principal Investigator:

Richard Parenteau, MD

ATP Clinical Research, Inc.

Recruiting

Orange, California, United States, 92866

Contacts

Christine Som

714-662-9556christines@pnsoc.com

Principal Investigator:

Gustavo Alva, MD

Riverside Clinical Research

Recruiting

Riverside, California, United States, 92506

Contacts

Erick Delgado

951-374-8000edelgado@irvineclinical.com

Principal Investigator:

Cydney Osano, MD

CenExel Sherman Oaks

Recruiting

Sherman Oaks, California, United States, 91403

Contacts

Mekaela Theobald

(818) 990-2671m.theobald@cenexel.com

Principal Investigator:

Thomas Shiovitz, MD

CenExel Denver, CO

Recruiting

Englewood, Colorado, United States, 80113

Contacts

Susan McPhie

720-477-7899rmcr.recruitment@cenexel.com

Principal Investigator:

Katherine Coerver, MD, PhD

JEM Research Institute

Recruiting

Atlantis, Florida, United States, 33462

Contacts

Linda Pao, MD

561-968-2933jem.research@jemri.net

Principal Investigator:

Linda Pao, MD

Brain Matters Research

Recruiting

Delray Beach, Florida, United States, 33445

Contacts

Jen Blasi

561-374-8461jblasi@ergclinical.com

RecruitmentBMR@ergclinical.com

Principal Investigator:

Paayal Patel, MD

Neuropsychiatric Research Center of Southwest Florida

Recruiting

Fort Myers, Florida, United States, 33912

Contacts

Jacqueline Acosta

239-939-7777recruitmentnprc@ergclinical.com

Principal Investigator:

Jennifer Springer, MD

Conquest Research - Lake Nona

Recruiting

Orlando, Florida, United States, 32832

Contacts

Daniela LaraRivillas

407-916-0060Daniela.LaraRivillas@conquestresearch.com

Principal Investigator:

Gilbert Mbeo, MD

Anchor Neuroscience

Recruiting

Pensacola, Florida, United States, 32502

Contacts

Jon Juliusson

850-433-1656jjuliusson@anchorneuroscience.com

Principal Investigator:

Kevin Groom, PhD

Progressive Medical Research

Recruiting

Port Orange, Florida, United States, 32127

Contacts

Kyrie Allen

386-304-7070kyriem@progressivemedicalresearch.com

Principal Investigator:

Alex White, MD

Alzheimer's Research and Treatment Center - Stuart

Recruiting

Stuart, Florida, United States, 34997

Contacts

Adam Falchook, MD

772-675-0000info@researchalz.com

Principal Investigator:

Adam Falchook, MD

Alzheimer's Research and Treatment Center - Wellington

Recruiting

Wellington, Florida, United States, 33414

Contacts

Annet Falchook, MD

561-209-2400info@researchalz.com

Principal Investigator:

Annet Falchook, MD

Columbus Memory Center

Recruiting

Columbus, Georgia, United States, 31909

Contacts

Mark Stafford

706-653-8455info@researchalz.com

Principal Investigator:

Mark Stafford, DO

Center for Advanced Research & Education Flourish-Gainesville

Recruiting

Gainsville, Georgia, United States, 30501

Contacts

Tina Foreman

770-534-5154tforeman@flourishresearch.com

Principal Investigator:

Angela Ritter, MD

Ascension via Christi Research

Recruiting

Wichita, Kansas, United States, 67214

Contacts

Angie Vincent

316-268-6055angie.vincent@ascension.org

Principal Investigator:

Paul Murphy, MD

Tandem Clinical Research - Metairie

Recruiting

Metairie, Louisiana, United States, 70006

Contacts

Tandem Clinical Research - Recruitment

504-321-1700recruitment@tandemclinicalresearch.com

Principal Investigator:

Angela Traylor, MD

Headlands PharmaSite

Recruiting

Pikesville, Maryland, United States, 21208

Contacts

Aparna Ayyala

410-699-9833aparna.ayyala@pharmasiteresearch.com

Principal Investigator:

Sarah Herts, DO

Adams Clinical Boston

Recruiting

Boston, Massachusetts, United States, 02116

Contacts

Megan Norris

617-362-4386mnorris@adamsclinical.com

Principal Investigator:

Darin Dougherty, MD

Headlands Research-EMA

Recruiting

Plymouth, Massachusetts, United States, 02360

Contacts

Jay Patel

508-746-5060jay.patel@headlandsresearchema.com

Principal Investigator:

Kinan Hreib, MD, PhD

Adams Clinical Watertown

Recruiting

Watertown, Massachusetts, United States, 02472

Contacts

Nova Chenda

617-362-4386Nchenda@adamsclinical.com

Principal Investigator:

Stephanie Rutrick, MD

Neurological Research Center - Hattiesburg Clinic

Recruiting

Hattiesburg, Mississippi, United States, 39401

Contacts

Krista-Elizabeth Hanley

601-579-5016bree.hanley@hattiesburgclinic.com

Principal Investigator:

Ronald Schwartz, MD

Clinical Research Professionals - Headlands

Recruiting

Chesterfield, Missouri, United States, 63005

Contacts

Recruitment

636-220-1200recruitment@clinicalresearchprofessionals.net

Principal Investigator:

Siddarth Kaul, MD, PhD

CenExel Research - Toms River

Recruiting

Toms River, New Jersey, United States, 08755

Contacts

Anna Brocco

732-341-9500amri.recruitment@cenexel.com

Principal Investigator:

Arun Singh, MD

IMA Evaluations

Recruiting

Albuquerque, New Mexico, United States, 87109

Contacts

Valerie Ramirez

505-848-3773valerie.ramirez@imaresearch.com

Principal Investigator:

Daniel Collins, MD

Alzheimer's Disease Research Center

Recruiting

Albany, New York, United States, 12208

Contacts

Richard Holub, MD

518-426-0575research@naaresearch.com

Principal Investigator:

Richard Holub, MD

Adams Clinic Harlem

Recruiting

New York, New York, United States, 10029

Contacts

Outreach Recruitment Team

646-917-6804jmoraleslu@adamsclinical.com

Principal Investigator:

Rachel Noone, MD

NDx Clinical Research

Recruiting

Dayton, Ohio, United States, 45459

Contacts

Study Team

937-224-8200Contact@NdxResearch.com

Principal Investigator:

Joel Vandersluis, MD

Summitt Research

Recruiting

Portland, Oregon, United States, 97210

Contacts

Annika Truitt

503-972-9822annika.truitt@summittnetwork.com

Principal Investigator:

Scott Losk, PhD

K2 Medical Research Nashville LLC

Recruiting

Nashville, Tennessee, United States, 37204

Contacts

Kerry Lovelace

615-208-5252kerry.lovelace@k2med.com

Principal Investigator:

Joshua Lennon, MD

Kerwin Research Center, LLC - Oak Cliff

Recruiting

Dallas, Texas, United States, 75216

Contacts

Megha Chadha

972-433-9100enroll@kerwinmedical.com

Principal Investigator:

Zaid Shah, DO

Kerwin Research Center, LLC in Texas

Recruiting

Dallas, Texas, United States, 75231

Contacts

Megha Chadha

972-433-9100enroll@kerwinmedical.com

Principal Investigator:

Alka Khera, MD

University of Virginia Adult Neurology

Recruiting

Charlottesville, Virginia, United States, 22903

Contacts

Colleen Webber

434-243-5898cmn6x@virginia.edu

Principal Investigator:

Carol Manning, PhD

Re-Cognition Health Fairfax

Recruiting

Fairfax, Virginia, United States, 22031

Contacts

Zakariya Al-Sarraf

571-418-0142zalsarraf@re-cognitionhealth.com

Principal Investigator:

Raymond S Turner, MD, PhD

Northwest Clinical Research Center

Recruiting

Bellevue, Washington, United States, 98007

Contacts

Study Coordinator

425-453-0404study.coordinator@nwcrc.net

study.coordinator@nwcrc.net

Principal Investigator:

Jeena Vaid, MD

More Information

Sponsor

Lighthouse Pharmaceuticals, Inc.

Last update posted

Aug 24, 2026

Last verified

Jun, 2026

Keywords

  • placebo-controlled
  • p. gingivalis
  • Alzheimer disease

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Lighthouse Pharmaceuticals, Inc. on 2026-08-24.