BACKGROUND:Chloroquine has in-vitro activity against influenza and could be an ideal candidate for worldwide prevention of influenza in the period between onset of a pandemic with a virulent influenza strain and the development and widespread dissemination of an effective vaccine. We aimed to assess the efficacy of such an intervention. METHODS: In this randomised, double-blind, placebo-controlled trial done at a single centre in Singapore, we randomly assigned (1:1) healthy adults to receive chloroquine phosphate (500 mg/day for 1 week, then once a week to complete 12 weeks) or matching placebo by use of a computer-generated randomisation list. Participants filled an online symptom diary every week, supplemented by daily diaries and self-administered nasal swabs when unwell. Haemagglutination-inhibition assays for influenza A (H1N1, H3N2) and B were done on blood samples taken at baseline and after 12 weeks. The primary outcome was laboratory-confirmed clinical influenza defined by specific symptoms accompanied by influenza RNA on nasal swabs or a four-fold increase in haemagglutination-inhibition titres over the 12-week study period. Analysis was by intention to treat. This trial was registered with ClinicalTrials.gov, number NCT01078779. FINDINGS:From November, 2009, to February, 2010, we recruited 1516 eligible participants. 1496 (96%) returned at week 12 and were included in the efficacy analysis. Adherence to study intervention was 97%, and 94% of the scheduled weekly diaries were completed. Eight (1%) of 738 participants had laboratory-confirmed clinical influenza in the placebo group and 12 (2%) of 724 in the chloroquine group (relative risk 1·53, 95% CI 0·63-3·72; p=0·376). 29 (4%) of 738 had laboratory-confirmed influenza infection (symptomatic or asymptomatic) in the placebo group and 38 (5%) of 724 in the chloroquine group (1·34, 0·83-2·14; p=0·261). 249 (33%) of 759 participants reported adverse events (mostly mild) in the placebo group and 341 (45%) of 757 in chloroquine group (p<0·0001). Headache, dizziness, nausea, diarrhoea, and blurred vision were more common in the chloroquine group, but rarely resulted in treatment discontinuation. One serious adverse event (hepatitis) was possibly related to chloroquine. INTERPRETATION: Although generally well tolerated by a healthy community population, chloroquine does not prevent infection with influenza. Alternative drugs are needed for large-scale prevention of influenza. FUNDING: National Medical Research Council, Singapore.
RCT Entities:
BACKGROUND:Chloroquine has in-vitro activity against influenza and could be an ideal candidate for worldwide prevention of influenza in the period between onset of a pandemic with a virulent influenza strain and the development and widespread dissemination of an effective vaccine. We aimed to assess the efficacy of such an intervention. METHODS: In this randomised, double-blind, placebo-controlled trial done at a single centre in Singapore, we randomly assigned (1:1) healthy adults to receive chloroquine phosphate (500 mg/day for 1 week, then once a week to complete 12 weeks) or matching placebo by use of a computer-generated randomisation list. Participants filled an online symptom diary every week, supplemented by daily diaries and self-administered nasal swabs when unwell. Haemagglutination-inhibition assays for influenza A (H1N1, H3N2) and B were done on blood samples taken at baseline and after 12 weeks. The primary outcome was laboratory-confirmed clinical influenza defined by specific symptoms accompanied by influenza RNA on nasal swabs or a four-fold increase in haemagglutination-inhibition titres over the 12-week study period. Analysis was by intention to treat. This trial was registered with ClinicalTrials.gov, number NCT01078779. FINDINGS: From November, 2009, to February, 2010, we recruited 1516 eligible participants. 1496 (96%) returned at week 12 and were included in the efficacy analysis. Adherence to study intervention was 97%, and 94% of the scheduled weekly diaries were completed. Eight (1%) of 738 participants had laboratory-confirmed clinical influenza in the placebo group and 12 (2%) of 724 in the chloroquine group (relative risk 1·53, 95% CI 0·63-3·72; p=0·376). 29 (4%) of 738 had laboratory-confirmed influenza infection (symptomatic or asymptomatic) in the placebo group and 38 (5%) of 724 in the chloroquine group (1·34, 0·83-2·14; p=0·261). 249 (33%) of 759 participants reported adverse events (mostly mild) in the placebo group and 341 (45%) of 757 in chloroquine group (p<0·0001). Headache, dizziness, nausea, diarrhoea, and blurred vision were more common in the chloroquine group, but rarely resulted in treatment discontinuation. One serious adverse event (hepatitis) was possibly related to chloroquine. INTERPRETATION: Although generally well tolerated by a healthy community population, chloroquine does not prevent infection with influenza. Alternative drugs are needed for large-scale prevention of influenza. FUNDING: National Medical Research Council, Singapore.
Authors: Jizhou Wang; Chunlong Ma; Jun Wang; Hyunil Jo; Belgin Canturk; Giacomo Fiorin; Lawrence H Pinto; Robert A Lamb; Michael L Klein; William F DeGrado Journal: J Med Chem Date: 2013-03-27 Impact factor: 7.446
Authors: Stuart D Dowall; Andrew Bosworth; Robert Watson; Kevin Bewley; Irene Taylor; Emma Rayner; Laura Hunter; Geoff Pearson; Linda Easterbrook; James Pitman; Roger Hewson; Miles W Carroll Journal: J Gen Virol Date: 2015-12 Impact factor: 3.891
Authors: Jun Wang; Yibing Wu; Chunlong Ma; Giacomo Fiorin; Jizhou Wang; Lawrence H Pinto; Robert A Lamb; Michael L Klein; William F Degrado Journal: Proc Natl Acad Sci U S A Date: 2013-01-09 Impact factor: 11.205