Impact of Generic Competition on Prices, Public Spending and Utilization of Antiepileptic Medicines in Bulgaria

OBJECTIVES: To analyze the impact of generic and therapeutic competition on lowest price per DDD (defined daily dose), public spending and utilization of antiepileptic medicines in Bulgaria.

METHODS: It is an observational, retrospective study of the changes in the number of newly included antiepileptic generic and therapeutic alternatives in the Positive Drug List (PDL) during 2015-2020 and the consecutive changes in the prices, public spending and utilization. 16 International Nonproprietary Names (INNs) belonging to ATC (Anatomical Therapeutic Chemical) codes N03AB, N03AE, N03AD, N03AF, N03AG, N03AX were observed. Medicines utilization is measured by formula: DDD/1000 inhabitants/day = ((Sales in mg/ DDD)/ (number of inhabitans×365)×1000).

RESULTS: One new INN (brivaracetam) is included and 5 INNs were excluded from PDL. The number of generics increased, whereas the number of branded products decreased - from 107 to 81. The lowest price per DDD decrease for 9 INNs with the highest rate for INN pregabalin (90 %), INN lacosamide (60.6 %), INN eslicarbazepine (48 %). The number of new products within the INN pregabalin and INN lacosamide are the highest. An increase in utilization is observed mainly for INN pregabalin and INN lacosamide (from 0.0618 to 0.2211 DDD/1000 inh/ day and 0.0435 to 0.0562 respectively). Public spending decreased by 9.2 % which is mainly due to declining reference price and number of dispensed packages during the observed period.

CONCLUSIONS: Generic competition reduces the lowest price per DDD, which has a favorable impact on the public spending for antiepileptic medicines and their utilization.