120. A Randomized Double-blind Trial Assessing the Efficacy of M72/AS01_E Vaccine Against Pulmonary Tuberculosis Disease in Adults With Latent Mycobacterium tuberculosis Infection

An effective tuberculosis (TB) vaccine is urgently needed to support the End TB Strategy to reduce the number of new TB cases by 80% by 2030. M72/AS01_E candidate vaccine is an adjuvanted recombinant fusion protein derived from Mycobacterium tuberculosis Mtb32A and Mtb39A proteins.

We conducted a randomized, double-blind, placebo-controlled phase 2b trial (NCT01755598) in Southern and Eastern Africa to assess M72/AS01_E’s efficacy against bacteriologically confirmed pulmonary TB disease in HIV-seronegative (HIV–) adults aged 18–50 years infected with Mtb (defined by a positive IFN-γ release assay). Participants were randomized 1:1 to receive M72/AS01_E or placebo at day D0 and D30. Reactogenicity, safety, immunogenicity were assessed, and incident TB disease measured from D30 postdose 2 up to ≥24 months for this analysis (follow-up ongoing up to 37 months). Efficacy against various TB disease case definitions (Figure 1) was estimated. Primary objective: efficacy against culture- or PCR-confirmed pulmonary TB disease in HIV– adults (case definition 1; success criterion: lower limit of 90% 2-sided CI >0%, power: 80%).

Demographic characteristics were similar between M72/AS01_E (1786) and placebo (1787) recipients. Efficacy against pulmonary TB disease case definition 1 was 54.0% (90% CI: 13.9, 75.4; P = 0.042); efficacy against other case definitions and a sensitivity analysis are shown in Figure 1. Leading solicited symptoms were pain, fatigue, and headache (Figure 2). In all recipients, unsolicited symptoms (D0–29) were more frequent after M72/AS01_E (67.4%) than placebo (45.4%), mainly attributable to increased injection site reactions and flu-like symptoms. Serious adverse events (D0–month 7) incidences were similar between groups (M72/AS01_E: 1.6%; placebo: 1.8%). During the study, 24 adults died (14 due to traumatic events); all deaths were unrelated to the trial.

M72/AS01_E presents a clinically acceptable safety profile and significantly reduces bacteriologically confirmed pulmonary TB disease incidence in HIV– adults with latent Mtb infection.

Funding. BMGF; Aeras; DFID UK; DGIS; AusAID; GlaxoSmithKline Biologicals SA.

O. Van Der Meeren, GSK: Employee and Shareholder, Salary. M. Hatherill, Aeras: Investigator, Research grant. R. J. Wilkinson, GSK: Grant Investigator, indirect funding. H. M. Ayles, GSK: Grant Investigator, Research grant. G. Henostroza, Aeras: Investigator, Grant recipient. M. A. Demoitié, GSK: owns stocks and is named inventor on patent applications relating to certain uses of M72/AS01E, Salary. T. Singh, GSK: Employee and Shareholder, Salary. E. J. Akite, GSK: Employee, Salary. A. K. Azam, GSK: Employee, Salary. A. Bollaerts, GSK: Employee, Salary. A. M. Ginsberg, GSK: Collaborator, Research support. BMGF: Grant Investigator, Grant recipient. UK DFID: Grant Investigator, Grant recipient. P. Gillard, GSK: Employee and Shareholder, Salary and stock. D. R. Tait, Aeras: Employee, Salary. GSK: Shareholder, Salary.