Recorded Systemic Antiviral Medicine Utilisation and Expenditure in Kazakhstan from 2013 to 2025: A Retrospective Database Study

Background/Objectives: Long-term drug-utilisation surveillance can identify changes in pharmaceutical distribution and expenditure. We examined recorded systemic antiviral utilisation, therapeutic composition and expenditure across three distribution channels in Kazakhstan during 2013–2025. Methods: Quarterly IQVIA records were analysed using World Health Organization Anatomical Therapeutic Chemical/Defined Daily Dose (ATC/DDD) methodology. Of 289 source product presentations, 273 met the eligibility criteria and 271 had an applicable defined daily dose (DDD). Utilisation was expressed as DDDs per 1,000 inhabitants per day (DID). Annual percentage changes (APCs) were estimated using log-linear models with robust covariance and sensitivity analyses. Recorded wholesale-sales values were adjusted to 2025 Kazakhstani tenge (KZT) using the official pharmaceutical consumer price index (CPI). Results: DDD-eligible presentations accounted for 279.66 million DDDs. Utilisation increased from 1.361 to 4.569 DID (APC 12.2%; 95% confidence interval 9.8–14.8). Retail commercial distribution represented 64.3% of the 2025 DDD-based total. Reimbursed outpatient utilisation increased fastest from a low, variable baseline. Total CPI-adjusted expenditure increased from KZT 12.983 billion to 30.147 billion. Within the matched DDD-eligible subset, expenditure per DDD decreased by 49.2%, from KZT 1,535 to 780. Conclusions: The findings identify retail distribution and therapeutic composition as priorities for surveillance and prescribing audits. Recorded sales do not establish treatment coverage, clinical appropriateness or procurement efficiency.