{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T04:28:36Z","timestamp":1791347316897,"version":"4.3.1"},"reference-count":28,"publisher":"SAGE Publications","issue":"4","license":[{"start":{"date-parts":[[2010,5,1]],"date-time":"2010-05-01T00:00:00Z","timestamp":1272672000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Antiviral Therapy"],"published-print":{"date-parts":[[2011,5]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Increasing efavirenz (EFV) dose from 600 mg to 800 mg daily has been suggested with concomitant rifampicin (RFN), as induction of cytochrome P450 isoenzymes may reduce EFV plasma concentrations<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Individuals from the CIPRA-South Africa cohort taking EFV-based antiretroviral therapy with concomitant tuberculosis (TB) were dosed with either increased (800 mg) or standard (600 mg) dose EFV during TB treatment. After TB therapy, all individuals took 600 mg EFV. Two mid-dosing interval EFV concentrations were determined from each individual: after 4 weeks of concomitant EFV and RFN therapy, and \u22654 weeks after TB therapy completion. Mid-dosing interval EFV concentrations were compared within individuals using the Wilcoxon signed\u2013 rank test.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Paired samples were collected from 72 individuals. Overall, 45 (63%) were women and median weight was 59 kg (IQR 52\u201367). At antiretroviral therapy start, median CD4\n                      <jats:sup>+<\/jats:sup>\n                      T-cell count was 114 cells\/mm\n                      <jats:sup>3<\/jats:sup>\n                      (IQR 37\u2013165), median viral load was 5.5 log (IQR 5.1\u20135.9). A total of 38 (53%) individuals took 800 mg EFV during TB treatment and 34 (47%) took 600 mg. EFV concentrations in the 800 mg group were higher with RFN (2.9 mg\/l [IQR 1.8\u20135.6]) than without (2.1 mg\/l [IQR 1.4\u20133.0]; P=0.0003). There was no significant difference in EFV concentrations with RFN (2.4 mg\/l [IQR 1.2\u20135.1]) or without (2.2 mg\/l [IQR 1.4\u20133.7]) in the 600 mg group. There was no increase in EFV-linked adverse effects in either group. The proportion of virologically suppressed individuals at 48 weeks was similar in both groups.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>EFV concentrations were significantly increased in the EFV 800 mg group on RFN. There was no significant decrease in EFV concentrations when on RFN in the 600 mg group. Dose escalation of EFV 600 mg to 800 mg is not required during concomitant TB therapy in South Africa.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3851\/imp1780","type":"journal-article","created":{"date-parts":[[2011,4,19]],"date-time":"2011-04-19T04:47:04Z","timestamp":1303188424000},"page":"527-534","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":27,"title":["Efavirenz and Rifampicin in the South African Context: Is There a Need to Dose-Increase Efavirenz with Concurrent Rifampicin Therapy?"],"prefix":"10.1177","volume":"16","author":[{"given":"Catherine","family":"Orrell","sequence":"first","affiliation":[{"name":"Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Cohen","sequence":"additional","affiliation":[{"name":"Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Conradie","sequence":"additional","affiliation":[{"name":"Clinical HIV Research Unit, University of Witwatersrand, Johannesburg, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"Zeinecker","sequence":"additional","affiliation":[{"name":"Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prudence","family":"Ive","sequence":"additional","affiliation":[{"name":"Clinical HIV Research Unit, University of Witwatersrand, Johannesburg, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ian","family":"Sanne","sequence":"additional","affiliation":[{"name":"Clinical HIV Research Unit, University of Witwatersrand, Johannesburg, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robin","family":"Wood","sequence":"additional","affiliation":[{"name":"Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2010,5,1]]},"reference":[{"key":"bibr1-IMP1780","unstructured":"National Department of Health, South Africa. National antiretroviral treatment guidelines. (Updated April 2004. Accessed 27 June 2010.) Available from http:\/\/hst.org.za\/uploads\/files\/sa_ART_Guidelines1.pdf."},{"key":"bibr2-IMP1780","unstructured":"National Department of Health, South Africa. Clinical guidelines for the management of HIV & AIDS in adults and adolescents. (Updated April 2010. Accessed 6 June 2010.) Available from http:\/\/www.doh.gov.za\/docs\/."},{"key":"bibr3-IMP1780","doi-asserted-by":"publisher","DOI":"10.1097\/00007691-200406000-00008"},{"key":"bibr4-IMP1780","doi-asserted-by":"publisher","DOI":"10.1097\/00002030-200101050-00011"},{"key":"bibr5-IMP1780","doi-asserted-by":"publisher","DOI":"10.1086\/497835"},{"key":"bibr6-IMP1780","doi-asserted-by":"crossref","first-page":"489","DOI":"10.1177\/135965350501000404","volume":"10","author":"Kappelhoff B.S.","year":"2005","journal-title":"Antivir Ther"},{"key":"bibr7-IMP1780","doi-asserted-by":"publisher","DOI":"10.1097\/00126334-200112010-00015"},{"key":"bibr8-IMP1780","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(02)08904-3"},{"key":"bibr9-IMP1780","unstructured":"National Department of Health, South Africa. South African tuberculosis control programme practical guidelines. (Updated 11 July 2000. Accessed 27 June 2010.) Available from http:\/\/www.capegateway.gov.za\/Text\/2003\/tb_guidelines2000.pdf."},{"key":"bibr10-IMP1780","doi-asserted-by":"publisher","DOI":"10.1164\/rccm.200709-1311PP"},{"key":"bibr11-IMP1780","unstructured":"Benedek I., Joshi A., Fiske W.O. Pharmacokinetic interaction between rifampicin and efavirenz in healthy volunteers.\n                      12th World AIDS Conference\n                      . 28 June\u20133 July 1998, Geneva, Switzerland. Abstract 42280."},{"key":"bibr12-IMP1780","doi-asserted-by":"publisher","DOI":"10.2165\/00003088-200241090-00004"},{"key":"bibr13-IMP1780","unstructured":"Sustiva (efavirenz) Package insert 2008. Prescribing Information. Bristol\u2013Meyers Squibb Pharma Company, Princeton, NJ, USA. (Updated November 2010. Accessed 27 June 2010.) Available from http:\/\/packageinserts.bms.com\/pi\/pi_sustiva.pdf."},{"key":"bibr14-IMP1780","unstructured":"Lewthwaite P., Gibbons S., Vilar F., Khoo S. Efavirenz, rifampicin and rifabutin \u2013 a case for therapeutic drug monitoring.\n                      2nd IAS Conference on HIV Pathogenesis and Treatment.\n                      13\u201316 July 2003, Paris, France. Abstract 851."},{"key":"bibr15-IMP1780","doi-asserted-by":"publisher","DOI":"10.1097\/01.aids.0000183519.45137.a6"},{"key":"bibr16-IMP1780","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.00899-08"},{"key":"bibr17-IMP1780","doi-asserted-by":"publisher","DOI":"10.1001\/jama.300.5.530"},{"key":"bibr18-IMP1780","doi-asserted-by":"publisher","DOI":"10.1590\/S1413-86702004000300004"},{"key":"bibr19-IMP1780","doi-asserted-by":"crossref","first-page":"687","DOI":"10.1177\/135965350901400502","volume":"14","author":"Cohen K.","year":"2009","journal-title":"Antivir Ther"},{"key":"bibr20-IMP1780","doi-asserted-by":"publisher","DOI":"10.1097\/01.aids.0000196181.18916.9b"},{"key":"bibr21-IMP1780","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(10)60894-X"},{"key":"bibr22-IMP1780","unstructured":"Division of AIDS table for grading the severity of adult and pediatric adverse events. Version 1.0, December 2004. (Updated August 2009. Accessed 07 April 2011.) Available from http:\/\/rcc.tech-res.com\/safetyandpharmacovigilance\/."},{"key":"bibr23-IMP1780","doi-asserted-by":"publisher","DOI":"10.1097\/QAI.0b013e31805c9d52"},{"key":"bibr24-IMP1780","doi-asserted-by":"publisher","DOI":"10.1016\/S0731-7085(02)00357-6"},{"key":"bibr25-IMP1780","unstructured":"Centers for Disease Control and Prevention. Managing drug interactions in the treatment of HIV-related tuberculosis. (Updated 18 May 2008. Accessed 4 January 2010.) Available from http:\/\/www.cdc.gov\/tb\/publications\/guidelines\/HIV_AIDS.htm."},{"key":"bibr26-IMP1780","doi-asserted-by":"publisher","DOI":"10.1517\/14656566.8.17.2947"},{"key":"bibr27-IMP1780","doi-asserted-by":"publisher","DOI":"10.1186\/1742-6405-7-8"},{"key":"bibr28-IMP1780","doi-asserted-by":"publisher","DOI":"10.1177\/0091270008315308"}],"container-title":["Antiviral Therapy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.3851\/IMP1780","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.3851\/IMP1780","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T12:50:05Z","timestamp":1777380605000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.3851\/IMP1780"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,5,1]]},"references-count":28,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2011,5]]}},"alternative-id":["10.3851\/IMP1780"],"URL":"https:\/\/doi.org\/10.3851\/imp1780","relation":{},"ISSN":["1359-6535","2040-2058"],"issn-type":[{"value":"1359-6535","type":"print"},{"value":"2040-2058","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,5,1]]}}}