As
HIV infection needs a lifelong treatment, studying
drug therapy duration and factors influencing treatment durability is crucial. The Swedish database InfCareHIV includes high quality data from more than 99% of all patients diagnosed with
HIV infection in Sweden and provides a unique opportunity to examine outcomes in a nationwide real world cohort.
METHODS: Adult patients who started a new
therapy defined as a new 3rd agent (all antiretrovirals that are not N[t]RTIs) 2009-2014 with more than 100 observations in treatment-naive or treatment-experienced patients were included.
Dolutegravir was excluded due to short follow up period. Multivariate Cox proportional hazards models were used to estimate hazard ratios for treatment discontinuation.
RESULTS: In treatment-naïve 2541 patients started 2583 episodes of treatments with a 3rd agent.
Efavirenz was most commonly used (n = 1096) followed by
darunavir (n = 504),
atazanavir (n = 386),
lopinavir (n = 292),
rilpivirine (n = 156) and
raltegravir (n = 149). In comparison with
efavirenz, patients on
rilpivirine were least likely to discontinue treatment (adjusted HR 0.33; 95% CI 0.20-0.54, p<0.001), while patients on
lopinavir were most likely to discontinue treatment (adjusted HR 2.80; 95% CI 2.30-3.40, p<0.001). Also
raltegravir was associated with early treatment discontinuation (adjusted HR 1.47; 95% CI 1.12-1.92, p = 0.005). The adjusted HR for
atazanavir and
darunavir were not significantly different from
efavirenz. In treatment-experienced 2991 patients started 4552 episodes of treatments with a 3rd agent.
Darunavir was most commonly used (n = 1285), followed by
atazanavir (n = 806),
efavirenz (n = 694),
raltegravir (n = 622),
rilpivirine (n = 592),
lopinavir (n = 291) and
etravirine (n = 262). Compared to
darunavir all other drugs except for
rilpivirine (HR 0.66; 95% CI 0.52-0.83, p<0.001) had higher risk for discontinuation in the multivariate adjusted analyses;
atazanavir (HR 1.71; 95% CI 1.48-1.97, p<0.001),
efavirenz (HR 1.86; 95% CI 1.59-2.17, p<0.001),
raltegravir (HR 1.35; 95% CI 1.15-1.58, p<0.001),
lopinavir (HR 3.58; 95% CI 3.02-4.25, p<0.001) and
etravirine (HR 1.61; 95% CI 1.31-1.98, p<0.001).Besides the 3rd agent chosen also certain baseline characteristics of patients were independently associated with differences in
treatment duration. In naive patients, presence of an
AIDS-defining diagnosis and the use of other backbone than TDF/
FTC or ABC/3TC increased the risk for early treatment discontinuation. In treatment-experienced patients, detectable plasma viral load at the time of switch or being highly treatment experienced increased the risk for early treatment discontinuation.
CONCLUSIONS: