Multicentre Study on the Use of Innovator and Generic Salmeterol/Fluticasone Combination in Asthma Management

Abstract

Introduction:
The Global Initiative of Asthma 2023 Guidelines recommend inhaled corticosteroid-containing treatments in asthma to reduce the risk of serious exacerbations and control symptoms. Generic substitution of the original salmeterol/fluticasone combination (SFC) has gained popularity due to cost considerations, although local studies assessing the efficacy of generic SFC are limited. This study aimed to compare the efficacy of innovator and generic SFC in asthma patients in terms of pulmonary function, asthma control symptoms, and hospitalisations.
Methods:
Conducted in Balik Pulau Hospital's outpatient department and Penang Hospital's respiratory department from January 2020 to May 2021, patients prescribed with innovator SFC in January 2020 or earlier, and were subsequently switched to generic SFC in September 2020 were enrolled. Treatment outcomes included forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), Asthma Control Test (ACT) score, and hospitalisations. Data were analysed using Statistical Package for the Social Sciences (SPSS) version 22, with paired-t test for inferential analysis of continuous data.
Results:
The study included 33 patients, primarily female (63.6%), Malay (48.5%), and aged over 71 years (45.5%). Innovator and generic SFC demonstrated comparable FEV1 (P=0.720), FVC (P=0.384), and FEV1/FVC (P=0.122) values. The ACT score significantly increased after switching to generic SFC (P=0.023). However, no significant difference in hospitalisations was observed.
Conclusion:
Spirometry improvements were comparable between innovator and generic SFC, while generic SFC exhibited superior control of asthma symptoms. This suggests that generic SFC can be considered as an effective and cost-efficient alternative to the innovator SFC in the management of asthma.