ObjectivesThe durability of combination antiretroviral therapy (cART) regimens can be measured as time to discontinuation because of toxicity or treatment failure, development of clinical disease or serious long-term adverse events. The aim of this analysis was to compare the durability of nevirapine, efavirenz and lopinavir regimens based on these measures.
MethodsPatients starting a nevirapine, efavirenz or lopinavir-based cART regimen for the first time after 1 January 2000 were included in the analysis. Follow-up started 3 months after initiation of treatment if viral load was o500 HIV-1 RNA copies/mL. Durability was measured as discontinuation rate or development/worsening of clinical markers.
ResultsA total of 603 patients (21%) started nevirapine-based cART, 1465 (51%) efavirenz, and 818 (28%) lopinavir. After adjustment there was no significant difference in the risk of discontinuation for any reason between the groups on nevirapine and efavirenz (P 5 0.43) or lopinavir (P 5 0.13). Compared with the nevirapine group, those on efavirenz had a 48% (P 5 0.0002) and those on lopinavir a 63% (Po0.0001) lower risk of discontinuation because of treatment failure and a 31% (P 5 0.01) and 66% (Po.0001) higher risk, respectively, of discontinuation because of toxicities or patient/physician choice. There were no significant differences in the incidence of non-AIDS-related events, worsening anaemia, severe weight loss, increased aspartate aminotransferase (AST)/alanine aminotransferase (ALT) levels or increased total cholesterol. Compared with patients on nevirapine, those on lopinavir had an 80% higher incidence of high-density lipoprotein (HDL) cholesterol decreasing below 0.9 mmol/L (P 5 0.003), but there was no significant difference in this variable between those on nevirapine and those on efavirenz (P 5 0.39).
ConclusionsThe long-term durability of nevirapine-based cART, based on risk of all-cause discontinuation and development of long-term adverse events, was comparable to that of efavirenz or lopinavir, in patients in routine clinical practice across Europe who initially tolerated and virologically responded to their regimen. [5][6][7]. Such long-term adverse events can influence the durability of a regimen. Combination antiretroviral therapy (cART) regimens most often include a nonnucleoside reverse transcriptase inhibitor, such as efavirenz or nevirapine, or a ritonavirboosted protease inhibitor, such as lopinavir [8,9]. cART regimens with durability as well as virological efficacy are required in order to achieve long-term virological suppression and to maintain CD4 cell counts at a level that significantly reduces the risk of morbidity and mortality. Many cohort studies have compared the short-term and long-term efficacies of different cART regimens [10][11][12][13][14], but less is known about the durability of different regimens, particularly in patients who have started a cART regimen more recently. If a regimen is virologically effective, durability can then be measured as the time to discontinuat...