Publication:

A retrospective evaluation of anti-retroviral therapy regimen modifications due to adverse drug reactions in a tertiary care hospital

Background Antiretroviral therapy (ART) has transformed HIV infection into a chronic manageable disease and substantially improved survival among people living with HIV. Despite these advances, adverse drug reactions (ADRs) remain a major cause of treatment modification, potentially affecting adherence, treatment continuity, and long-term outcomes. Real-world pharmacovigilance data describing ADR-driven ART regimen changes in Indian settings remain limited. Aim was to evaluate the frequency and pattern of ART regimen modifications attributable to ADRs reported to the adverse drug reaction monitoring centre (AMC) of a tertiary care teaching hospital.

Methods A retrospective observational study was conducted using suspected ADR reporting forms received at the AMC, department of pharmacology, Mysore Medical College and Research Institute between January 2022 and December 2024. Data regarding patient demographics, ADR characteristics, suspected antiretroviral agents, and regimen modifications were extracted and analysed using descriptive statistics. The association between ADR type and regimen modification was assessed using the Chi-square test.

Results A total of 93 ART-related ADR reports were analysed. Among them, 67 patients (72.0%) required modification of their ART regimen following an ADR. Renal ADRs were the most frequently reported reactions (67.7%), with tenofovir-based regimens accounting for the largest proportion of implicated drugs. Patients experiencing renal toxicity were significantly more likely to undergo regimen modification compared with those experiencing non-renal ADRs (χ2=24.45, p<0.001). Substitution from tenofovir-containing regimens to alternative regimens, particularly abacavir-based combinations, represented the most common modification pattern.

Conclusions ADRs continue to be an important determinant of ART regimen modification in routine clinical practice. Renal toxicity, predominantly associated with tenofovir-containing regimens, emerged as the leading reason for treatment substitution. These findings highlight the importance of vigilant pharmacovigilance, timely recognition of drug-related toxicity, and routine renal function monitoring to support safer and more sustainable ART use.