In their Review on chikungunya, Gilles Pialoux and colleagues1 quote a Reflection and Reaction commentary previously published by our group2 as the source for the statement that “a clinical trial in South Africa failed to confirm the clinical efficacy of chloroquine on arthralgia”. It is true that chloroquine displays antiviral and anti-inflammatory properties that, in our opinion, merit testing in the clinical management of some viral diseases. However, we reported no data on chikungunya, nor did we mention this disease in our articles in The Lancet Infectious Diseases.2, 3 Our research has so far been focused on the effects of chloroquine on HIV-1,4 severe acute respiratory syndrome coronavirus,3 influenza A viruses,5 and cancer cells.6 It is our policy to suggest new ideas only when they are supported by robust experimental results, which are highly reproducible in different laboratory settings.7, 8, 9, 10 Furthermore, clinical trials in Réunion on chloroquine as a potential antiviral for chikungunya cannot be linked to our previous studies, in that the chloroquine dosage adopted (ie, 250 mg daily)11 is inconsistent with the tissue drug concentrations that we report are necessary to inhibit the aforementioned viruses.2, 12
Acknowledgments
We declare that we have no conflicts of interest.
References
- 1.Pialoux G, Gaüzère BA, Jauréguiberry S, Strobel M. Chikungunya, an epidemic arbovirosis. Lancet Infect Dis. 2007;7:319–327. doi: 10.1016/S1473-3099(07)70107-X. [DOI] [PubMed] [Google Scholar]
- 2.Savarino A, Di Trani L, Donatelli I, Cauda R, Cassone A. New insights into the antiviral effects of chloroquine. Lancet Infect Dis. 2006;6:67–69. doi: 10.1016/S1473-3099(06)70361-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Savarino A, Boelaert JR, Cassone A, Majori G, Cauda R. Effects of chloroquine on viral infections: an old drug against today's diseases. Lancet Infect Dis. 2003;3:722–727. doi: 10.1016/S1473-3099(03)00806-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Savarino A, Lucia MB, Rastrelli E. Anti-HIV effects of chloroquine: inhibition of viral particle glycosylation and synergism with protease inhibitors. J Acquir Immune Defic Syndr. 2004;35:223–232. doi: 10.1097/00126334-200403010-00002. [DOI] [PubMed] [Google Scholar]
- 5.Di Trani L, Savarino A, Campitelli L. Different pH requirements are associated with divergent inhibitory effects of chloroquine on human and avian influenza A viruses. Virol J. 2007;4:39. doi: 10.1186/1743-422X-4-39. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Savarino A, Lucia MB, Giordano F, Cauda R. Risks and benefits of chloroquine use in anticancer strategies. Lancet Oncol. 2006;7:792–793. doi: 10.1016/S1470-2045(06)70875-0. [DOI] [PubMed] [Google Scholar]
- 7.Naarding MA, Baan E, Pollakis G, Paxton WA. Effect of chloroquine on reducing HIV-1 replication in vitro and the DC-SIGN mediated transfer of virus to CD4+ T-lymphocytes. Retrovirology. 2007;4:6. doi: 10.1186/1742-4690-4-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Keyaerts E, Vijgen L, Maes P, Neyts J, Van Ranst M. In vitro inhibition of severe acute respiratory syndrome coronavirus by chloroquine. Biochem Biophys Res Commun. 2004;323:264–268. doi: 10.1016/j.bbrc.2004.08.085. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Ooi EE, Chew JS, Loh JP, Chua RC. In vitro inhibition of human influenza A virus replication by chloroquine. Virol J. 2006;3:39. doi: 10.1186/1743-422X-3-39. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Sundberg AL, Steffen AC. Enhancing the effect of radionuclide tumor targeting, using lysosomotropic weak bases. Int J Radiat Oncol Biol Phys. 2007;67:279–287. doi: 10.1016/j.ijrobp.2006.07.1369. [DOI] [PubMed] [Google Scholar]
- 11.The ClinicalTrials.Gov database. CuraChik: a trial of the efficacy and safety of chloroquine as therapeutic treatment of chikungunya disease http://clinicaltrials.gov/ct/show/NCT00391313;jsessionid=F91ADE5077910A5240B7AA9AA7666FA8?order=1 (accessed Aug 9, 2007).
- 12.Savarino A, Lucia MB, ter Heine R. Quinoline antimalarials as investigational drugs for HIV-1/AIDS: in vitro effects on HIV-1 replication, HIV-1 response to antiretroviral drugs, and intracellular antiretroviral drug concentrations. Drug Dev Res. 2006;67:806–817. [Google Scholar]