Major trial tests first new lyme vaccine in decades

NCT ID NCT05477524

ACTIVE_NOT_RECRUITING ⭐️ VACCINE ⭐️ Sponsor: Pfizer Source: ClinicalTrials.gov ↗

Lyme Vaccine Hits 70%+ Protection in Phase 3

In Phase 3, the Lyme vaccine candidate showed about 73–75% efficacy in people age 5+ after the 4-dose schedule, with no major safety concerns seen at analysis. One strict statistical checkpoint in the first pre-planned analysis was narrowly missed because fewer Lyme cases occurred than expected, but a second pre-planned analysis cleared the key threshold. Pfizer says it plans regulatory submissions. The results are encouraging and clinically meaningful, but they’re not absolute proof yet.

Think of this vaccine trial like testing a new umbrella in real weather. The Phase 3 VALOR trial showed the umbrella worked: the vaccine reduced confirmed Lyme cases by roughly three quarters compared with placebo after dose 4.

More specifically, the trial reported:

73.2% efficacy from 28 days after dose 4
74.8% efficacy from 1 day after dose 4
Participants were age 5+
No major safety signal was flagged at the time of analysis

There is one important nuance: the trial had a strict statistical checkpoint in its first primary analysis (confidence interval lower bound had to be above 20), and that exact bar was not met there, partly because fewer Lyme cases occurred than expected. But in the second pre-specified analysis, the lower bound was above 20, and Pfizer/Valneva say the overall efficacy signal remains clinically meaningful.

Bottom line in everyday terms: this looks like a strong “yes, this can work” signal, not a perfect or final finish line yet.

What happens next — full redo or not?

Short answer: probably not a full redo, based on what’s public right now.

More likely scenarios:

regulators ask for deeper analyses / subgroup breakdowns
possible post-approval commitments or extra confirmatory follow-up
label/scope discussions rather than “start over”

Because they still showed strong efficacy in pre-specified analyses and are moving toward submissions, this looks more like a regulatory negotiation + evidence package question than a total reset.

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Locations

ALERGO-MED Specjalistyczna Przychodnia Lekarska

Tarnów, Lesser Poland Voivodeship, 33-100, Poland
ActivMed Practices & Research, LLC.

Portsmouth, New Hampshire, 03801, United States
ActivMed Practices and Research

Methuen, Massachusetts, 01844, United States
Allegheny Health and Wellness Pavilion

Erie, Pennsylvania, 16506, United States
Altoona Center For Clinical Research

Duncansville, Pennsylvania, 16635, United States
AmBeNet GmbH

Leipzig, Saxony, 04107, Germany
Amherst Family Practice, P.C.

Winchester, Virginia, 22601, United States
Amsterdam UMC, locatie AMC

Amsterdam, North Holland, 1105 AZ, Netherlands
Bassett Medical Center

Cooperstown, New York, 13326, United States
Blekinge Tekniska Hogskola (BTH) (Blekinge Institute of Technology) - Karlskrona

Karlskrona, Blekinge LÄN [se-10], 371 79, Sweden
Bluewater Clinical Research Group Inc.

Sarnia, Ontario, N7T 4X3, Canada
CCP - Kid's Way

Hermitage, Pennsylvania, 16148, United States
CTC Karolinska

Solna, Stockholms LÄN [se-01], 171 64, Sweden
CTC MTC

Uppsala, Uppsala LÄN [se-03], 752 37, Sweden
Canadian Center for Vaccinology

Halifax, Nova Scotia, B3K6R8, Canada
Care Access - Albany

Halfmoon, New York, 12065, United States
Care Access - Brattleboro

Brattleboro, Vermont, 05301, United States
Care Access - Brattleboro - Putney Road

Brattleboro, Vermont, 05301, United States
Care Access - Briarpatch and Mobile Site

Nantucket, Massachusetts, 02554, United States
Care Access - Essex

Essex, Connecticut, 06426, United States
Care Access - Farmington

Farmington, Maine, 04938, United States
Care Access - Hingham

Rockland, Massachusetts, 02370, United States
Care Access - Hoboken

Hoboken, New Jersey, 07030, United States
Care Access - Kingston

Kingston, Pennsylvania, 18704, United States
Care Access - Lakeville

Lakeville, Massachusetts, 02347, United States
Care Access - Londonderry

Londonderry, New Hampshire, 03053, United States
Care Access - Melrose

Melrose, Massachusetts, 02176, United States
Care Access - Middlebury

Middlebury (village), Vermont, 05753, United States
Care Access - Mountaintop

Hazle Township, Pennsylvania, 18202, United States
Care Access - Nantucket

Nantucket, Massachusetts, 02554, United States
Care Access - North Conway

North Conway, New Hampshire, 03860, United States
Care Access - Pottsville

Pottsville, Pennsylvania, 17901, United States
Care Access - Scranton

Scranton, Pennsylvania, 18508, United States
Care Access - Wareham

Wareham, Massachusetts, 02571, United States
Care Access - Warwick

Warwick, Rhode Island, 02886, United States
Care Access - Wilkes-Barre

Wilkes-Barre, Pennsylvania, 18702, United States
Care Access Mobile Site

New London, Connecticut, 06320, United States
Care Access Mobile Site

Nantucket, Massachusetts, 02554, United States
Care Access Mobile Site

Punxsutawney, Pennsylvania, 15767, United States
Care Access Mobile Site

Yeagertown, Pennsylvania, 17099, United States
Care Access Mobile Site

New Shoreham, Rhode Island, 02807, United States
Central Erie Primary Care

Erie, Pennsylvania, 16508, United States
Centricity Research Burlington Multispecialty

Burlington, Ontario, L7M 4Y1, Canada
Centricity Research Toronto Manna Multispecialty

Toronto, Ontario, M9W 4L6, Canada
Centrum Badan Klinicznych Jagiellonskie Centrum Innowacji

Krakow, 30-348, Poland
Centrum Medyczne AD-MED Sp. z o. o. Przychodnia Dla Rodziny

Wroclaw, 51-141, Poland
Centrum Medyczne Lucyna Andrzej Dymek

Strzelce Opolskie, Opole Voivodeship, 47-100, Poland
Clinical Research Institute

Minneapolis, Minnesota, 55402, United States
Clinilabs

Eatontown, New Jersey, 07724, United States
Diex Recherche Sherbrooke

Sherbrooke, Quebec, J1L 0H8, Canada
Diex Recherche Victoriaville

Victoriaville, Quebec, G6P 3Z8, Canada
FVR, Etelä-Helsingin rokotetutkimusklinikka

Helsinki, Uusimaa, 00100, Finland
FVR, Itä-Helsingin rokotetutkimusklinikka

Helsinki, Uusimaa, 00930, Finland
FVR, Järvenpään rokotetutkimusklinikka

Jarvenpaa, Uusimaa, 04400, Finland
FVR, Kokkolan rokotetutkimusklinikka

Kokkola, 67100, Finland
FVR, Porin rokotetutkimusklinikka

Pori, 28100, Finland
FVR, Tampereen rokotetutkimusklinikka

Tampere, Pirkanmaa, 33100, Finland
FVR, Turun rokotetutkimusklinikka

Turku, Southwest Finland, 20520, Finland
Frontier Clinical Research, LLC

Scottdale, Pennsylvania, 15683, United States
Frontier Clinical Research, LLC

Smithfield, Pennsylvania, 15478, United States
Futuremeds spolka z ograniczona odpowiedzialnoscia

Wroclaw, Lower Silesian Voivodeship, 53-673, Poland
Guthrie Medical Group, P.C.

Sayre, Pennsylvania, 18840, United States
Hunterdon Infectious Disease Specialists

Flemington, New Jersey, 08822, United States
Hunterdon Medical Center

Flemington, New Jersey, 08822, United States
IMA Clinical Research Warren

Warren Township, New Jersey, 07059, United States
Indywidualna Specjalistyczna Praktyka Lekarska Roman Spyra

Katowice, 40-018, Poland
Internal Medicine Associates

Bridgeton, New Jersey, 08302, United States
Internistische Gemeinschaftspraxis Mainz

Mainz, 55116, Germany
Johns Hopkins

Baltimore, Maryland, 21205, United States
Johns Hopkins Hospital

Baltimore, Maryland, 21287, United States
Johns Hopkins Rockland Physician Practice and Research Group

Lutherville, Maryland, 21093, United States
Krakowski Szpital Specjalistyczny im. Jana Pawa II

Krakow, Lesser Poland Voivodeship, 31-202, Poland
Krakowskie Centrum Medyczne

Krakow, 31-501, Poland
MICS Centrum Medyczne Torun

Torun, Kuyavian-Pomeranian Voivodeship, 87-100, Poland
Marshfield Medical Center - Marshfield

Marshfield, Wisconsin, 54449, United States
Marshfield Medical Center - Weston

Weston, Wisconsin, 54476, United States
MeVac - Meilahti Vaccine Research Center

Helsinki, 00290, Finland
Mid Hudson Medical Research

New Windsor, New York, 12553, United States
Milestone Research Inc.

London, Ontario, N5W 6A2, Canada
NZOZ Praktyka Lekarza Rodzinnego Eskulap

Lublin, 20-044, Poland
Northeast Clinical Trials Group

Scranton, Pennsylvania, 18510, United States
Northern Light Eastern Maine Medical Center

Bangor, Maine, 04401, United States
Pediatric Associates of Fall River

Fall River, Massachusetts, 02721, United States
Pen Bay Medical Center

Rockport, Maine, 04856, United States
Preferred Primary Care Physicians

Uniontown, Pennsylvania, 15401, United States
Preferred Primary Care Physicians, Preferred Clinical Research (Ofc 18)

Pittsburgh, Pennsylvania, 15236, United States
Preferred Primary Care Physicians, Preferred Clinical Research-St. Clair

Pittsburgh, Pennsylvania, 15243, United States
ProbarE

Lund, 222 22, Sweden
Przychodnia EuroMediCare Wroclaw Lowiecka

Wroclaw, 50-220, Poland
Przylądek Zdrowia

Krakow, Lesser Poland Voivodeship, 30-644, Poland
Robert Packer Hospital

Sayre, Pennsylvania, 18840, United States
Rodzinne Centrum Medyczne LUBMED

Luboń, Greater Poland Voivodeship, 62-030, Poland
SZPZOZ im. Dzieci Warszawy w Dziekanowie Lesnym

Łomianki, Masovian Voivodeship, 05-092, Poland
Sisu BHR

Springfield, Massachusetts, 01103, United States
Smith Allergy & Asthma Specialists

Horseheads, New York, 14845, United States
Smith Allergy and Asthma Specialists

Cortland, New York, 13045, United States
South Shore Hospital

Weymouth, Massachusetts, 02190, United States
South Shore Medical Center

Norwell, Massachusetts, 02061, United States
Stamford Health Medical Group

Stamford, Connecticut, 06902, United States
Stamford Hospital

Stamford, Connecticut, 06904, United States
Stouffville Medical Research Institute Inc.

Stouffville, Ontario, L4A 1H2, Canada
Studieenheten Akademiskt Specialistcentrum

Stockholm, Stockholms LÄN [se-01], 113 61, Sweden
Sumit Bhutani MD LLC

Westminster, Maryland, 21157, United States
Synexus Polska Sp. z o.o. Oddzial w Gdyni

Gdynia, 81-537, Poland
Szpital im. Św. Jadwigi Śląskiej w Trzebnicy

Trzebnica, Lower Silesian Voivodeship, 55-100, Poland
Terveystalo Pulssi

Turku, 20100, Finland
The Ottawa Hospital - General Campus

Ottawa, Ontario, K1H 8L6, Canada
The University of Vermont Medical Center Inc.

Burlington, Vermont, 05401, United States
TruCare Internal Medicine & Infectious Disease

DuBois, Pennsylvania, 15801, United States
Universitetssjukhuset Örebro

Örebro, Örebro LÄN [se-18], 701 85, Sweden
University of Massachusetts Chan Medical School

Worcester, Massachusetts, 01655, United States
University of Wisconsin Carbone Cancer Center-University Hospital

Madison, Wisconsin, 53792, United States
Uniwersytecki Szpital Kliniczny w Bialymstoku

Bialystok, 15-274, Poland
Uniwersytecki Szpital Kliniczny w Bialymstoku

Bialystok, 15-540, Poland
Velocity Clinical Research, Binghamton

Binghamton, New York, 13905, United States
Velocity Clinical Research, Providence

East Greenwich, Rhode Island, 02818, United States
Velocity Clinical Research, Vestal

Vestal, New York, 13850, United States
Viable Clinical Research Corporation

Bridgewater, Nova Scotia, B4V 3N2, Canada
Woodholme Gastroenterology Associates

Westminster, Maryland, 21157, United States
Zespol Opieki Zdrowotnej w Boleslawcu

Bolesławiec, 59-700, Poland

Conditions

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LYME DISEASE