Jan Pieter R Koopman, Emma L Houlder, Jacqueline J Janse, Olivia Ac Lamers, Geert Vt Roozen, Jeroen C Sijtsma, Miriam Casacuberta-Partal, Stan T Hilt, M Y Eileen C van der Stoep, Inge M van Amerongen-Westra, Eric At Brienen, Linda J Wammes, Lisette van Lieshout, Govert J van Dam, Paul Lam Corstjens, Angela van Diepen, Maria Yazdanbakhsh, Cornelis H Hokke, Meta Roestenberg
{"title":"Clinical tolerance but no protective efficacy in a placebo-controlled trial of repeated controlled schistosome infection.","authors":"Jan Pieter R Koopman, Emma L Houlder, Jacqueline J Janse, Olivia Ac Lamers, Geert Vt Roozen, Jeroen C Sijtsma, Miriam Casacuberta-Partal, Stan T Hilt, M Y Eileen C van der Stoep, Inge M van Amerongen-Westra, Eric At Brienen, Linda J Wammes, Lisette van Lieshout, Govert J van Dam, Paul Lam Corstjens, Angela van Diepen, Maria Yazdanbakhsh, Cornelis H Hokke, Meta Roestenberg","doi":"10.1172/JCI185422","DOIUrl":null,"url":null,"abstract":"<p><p>BACKGROUNDPartial protective immunity to schistosomiasis develops over time, following repeated praziquantel (PZQ) treatment. Moreover, animals develop protective immunity after repeated immunization with irradiated cercariae. Here, we evaluated the development of natural immunity through consecutive exposure-treatment cycles with Schistosoma mansoni in healthy, Schistosoma-naive participants using single-sex, controlled human S. mansoni infection.METHODSTwenty-four participants were randomized in a double-blinded (1:1) manner to either the reinfection group, which received 3 exposures (weeks 0, 9, and 18) to 20 male cercariae, or to the infection control group, which received 2 mock exposures with water (weeks 0 and 9) prior to cercariae exposure (week 18). Participants were treated with PZQ (or placebo) at weeks 8, 17, and 30. Attack rates (ARs) after the final exposure (weeks 19-30) using serum circulating anodic antigen (CAA) positivity were compared between groups. Adverse events (AEs) were collected for safety.RESULTSTwenty-three participants completed the follow-up. No protective efficacy was observed, given an 82% (9 of 11) AR after the final exposure in the reinfection group and 92% (11 of 12) in the infection control group (protective efficacy 11%; 95% CI -24% to 35%; P = 0.5). Related AEs were higher after the first infection (45%) compared with the second (27%) and third (28%) infections. Severe acute schistosomiasis was observed after the first infections only (2 of 12 in the reinfection group and 2 of 12 in the infection control group).CONCLUSIONRepeated Schistosoma exposure and treatment cycles resulted in apparent clinical tolerance, with fewer symptoms reported following subsequent infections, but did not result in protection against reinfection.TRIAL REGISTRATIONClinicalTrials.gov NCT05085470.FUNDINGEuropean Research Council (ERC) Starting Grant (no. 101075876).</p>","PeriodicalId":15469,"journal":{"name":"Journal of Clinical Investigation","volume":" ","pages":""},"PeriodicalIF":13.3000,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11827845/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Clinical Investigation","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1172/JCI185422","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MEDICINE, RESEARCH & EXPERIMENTAL","Score":null,"Total":0}
引用次数: 0
Abstract
BACKGROUNDPartial protective immunity to schistosomiasis develops over time, following repeated praziquantel (PZQ) treatment. Moreover, animals develop protective immunity after repeated immunization with irradiated cercariae. Here, we evaluated the development of natural immunity through consecutive exposure-treatment cycles with Schistosoma mansoni in healthy, Schistosoma-naive participants using single-sex, controlled human S. mansoni infection.METHODSTwenty-four participants were randomized in a double-blinded (1:1) manner to either the reinfection group, which received 3 exposures (weeks 0, 9, and 18) to 20 male cercariae, or to the infection control group, which received 2 mock exposures with water (weeks 0 and 9) prior to cercariae exposure (week 18). Participants were treated with PZQ (or placebo) at weeks 8, 17, and 30. Attack rates (ARs) after the final exposure (weeks 19-30) using serum circulating anodic antigen (CAA) positivity were compared between groups. Adverse events (AEs) were collected for safety.RESULTSTwenty-three participants completed the follow-up. No protective efficacy was observed, given an 82% (9 of 11) AR after the final exposure in the reinfection group and 92% (11 of 12) in the infection control group (protective efficacy 11%; 95% CI -24% to 35%; P = 0.5). Related AEs were higher after the first infection (45%) compared with the second (27%) and third (28%) infections. Severe acute schistosomiasis was observed after the first infections only (2 of 12 in the reinfection group and 2 of 12 in the infection control group).CONCLUSIONRepeated Schistosoma exposure and treatment cycles resulted in apparent clinical tolerance, with fewer symptoms reported following subsequent infections, but did not result in protection against reinfection.TRIAL REGISTRATIONClinicalTrials.gov NCT05085470.FUNDINGEuropean Research Council (ERC) Starting Grant (no. 101075876).
期刊介绍:
The Journal of Clinical Investigation, established in 1924 by the ASCI, is a prestigious publication that focuses on breakthroughs in basic and clinical biomedical science, with the goal of advancing the field of medicine. With an impressive Impact Factor of 15.9 in 2022, it is recognized as one of the leading journals in the "Medicine, Research & Experimental" category of the Web of Science.
The journal attracts a diverse readership from various medical disciplines and sectors. It publishes a wide range of research articles encompassing all biomedical specialties, including Autoimmunity, Gastroenterology, Immunology, Metabolism, Nephrology, Neuroscience, Oncology, Pulmonology, Vascular Biology, and many others.
The Editorial Board consists of esteemed academic editors who possess extensive expertise in their respective fields. They are actively involved in research, ensuring the journal's high standards of publication and scientific rigor.