biostudies-literatureUnknown392(18)Schmidt AC<h4>Background</h4>In a previous phase 2 trial, bacille Calmette-Guérin (BCG) revaccination was not shown to provide protection from primary <i>Mycobacterium tuberculosis</i> infection but prevented sustained <i>M. tuberculosis</i> infection, defined by an initial conversion on a QuantiFERON-TB (QFT) test (an interferon-<i>γ</i> release assay) from negative to positive, followed by two additional positive QFT tests at 3 and 6 months after the initial conversion (a secondary end point). A vaccine efficacy of 45% (95% confidence interval [CI], 6 to 68) was observed.<h4>Methods</h4>We performed a phase 2b, double-blind, randomized, placebo-controlled trial to evaluate the efficacy of BCG revaccination, as compared with placebo, for the prevention of sustained QFT test conversion (primary end The New England journal of medicine1789-1800https://www.ebi.ac.uk/biostudies/studies/S-EPMC12061034biostudies-literatureBCG Revaccination for the Prevention of &lt;i&gt;Mycobacterium tuberculosis&lt;/i&gt; Infection.PMC12061034Williams MDada TVelden MVBailey EKaufman Dde Kock MLuabeya Kany Kany AJeffrey LMkhize ZGrab JRawoot JDunne MWNkambule HCinar AStewart JBilek NSebastian EDanster NTshongoyi NKomane RPatel FMukoko VMlotshwa VGroenewald JPote DHolm ANtanjana MAfrica HGxako XMangali SSoma-Kasiram HHans CKhiya NGwamanda ZOosthuizen AKelepu XScotch NGerber MJeffery LInnes SJacobs ESchmidt ACHellstrom ENkosi SCloete YTelite ZPearce NScriba TJKoegelenberg WATheron AMkhize HHerling RVakala KDiamond BHlathi SMafilika LSchreuder CMacdonald PMshudulu NNgqabe NMoopanar KBonakele NHoward RMvinjelwa PMiddelkoop KMthombeni SMona NDavids ISteyn MMocumi KSaal CLNtombela NHorne EMogg RNemes EDyanti SBusisiwe Ntsalaze VSeef TBCG REVAX Study TeamGogo LSpeckman BNombida OFrahm NStryers SMahoney SMakhamba PMayekiso NMsomi SMusvosvi MRirhandzu Ndzhukule TJaxa LJansen RImbratta CMnqebisa BSing PNaidoo KFortuin ENqakala NShangase NMbiza NMahed FYekani LStrumper HMaarman Mvan der Linde ASegalo ONompondwana MMagobiane NCoba TNdlovu SVan Der Merve MTose BMoosa AGool KMalan GValley HMasenya MGeduld SBall CDorse GZuma JMyburgh JMYola TErasmus MDukwe PTofile TCruywagen LMgxekeza NMzizi IGela ADaki TMoloi MAndersen CMuller JMactavie LNair GNcayiya CArnolds SMaqungo LIsmail AMbhele SAmsterdam JNgcobo LNair LZoneleni NDlamini DCoetzee JFairlie LKhaya BNqwede MHorak JMpongo NTredoux NGumede GKiribikiri EHatherill MNashwa NMatolengwe NSmitsdorff BSizani LAkhalwaya SGumede SHonono TFleurs LGumula WCetwayo NKingwill MKhan MMthethi ZMathiso YNtuli TGelant JMakhethe LfalseBCG Revaccination for the Prevention of &lt;i&gt;Mycobacterium tuberculosis&lt;/i&gt; Infection.<h4>Background</h4>In a previous phase 2 trial, bacille Calmette-Guérin (BCG) revaccination was not shown to provide protection from primary <i>Mycobacterium tuberculosis</i> infection but prevented sustained <i>M. tuberculosis</i> infection, defined by an initial conversion on a QuantiFERON-TB (QFT) test (an interferon-<i>γ</i> release assay) from negative to positive, followed by two additional positive QFT tests at 3 and 6 months after the initial conversion (a secondary end point). A vaccine efficacy of 45% (95% confidence interval [CI], 6 to 68) was observed.<h4>Methods</h4>We performed a phase 2b, double-blind, randomized, placebo-controlled trial to evaluate the efficacy of BCG revaccination, as compared with placebo, for the prevention of sustained QFT test conversion (primary end 2025-01-01T00:00:00Z2025 May2026-06-01T22:25:00.654Z2026-05-22T03:08:18.361ZS-EPMC120610344033415610.1056/NEJMoa2412381