Patient Characteristics and Treatment Outcome Associated with Protease Inhibitor (PI) use in the Asia-Pacific Region

Abstract

OBJECTIVES: Regimens containing protease inhibitors (PI) are less commonly used in developing countries due to high cost and less availability. We evaluated characteristics of patients initiating PI-based therapy according to previous antiretroviral (ARV) exposure; factors associated with initiating a PI-containing regimen using newer versus older PIs, and proportion of patients with detectable viral loads (VL) after initiating a PI-based regimen. METHODS: This analysis includes all patients who have initiated a PI-based regimen. ARV exposure was categorised: naïve (no previous ARV), 1st, 2nd, >/= 3rd switches; a switch was defined as starting or stopping any drug in a regimen. Newer PIs were defined as those approved by the US FDA after 1 January 2000. Detectable VL at 12 months was defined as VL >/= 400 copies/mL. Characteristics at PI initiation were evaluated. Logistic regression was used to determine factors associated with initiating a newer PI and detectable VL at 12 months after PI initiation. RESULTS: 1106 patients initiated PI-based therapy; of these, 618 (56%) were naïve patients. Overall, 22% (176) of patients had detectable VL at 12 months following the PI initiation. Being from a high income country (vs. mid/low income, OR = 1.80, p = 0.034) were more likely to be associated with detectable VL. CONCLUSION: The use of PIs in this cohort is dictated by accessibility and affordability issues particularly for the newer PIs. Short-term virological outcomes following PI-therapy in our cohort were good, and were associated with CD4 count at time of initiation.