Addressing the palatability challenges of liquid nicotinamide formulations

Abstract

Nicotinamide (NAM), commonly known as vitamin B3, has emerged as a potential therapeutic agent for juvenile idiopathic arthritis (JIA). However, its inherent bitterness poses a challenge, particularly for pediatric patients who may struggle with swallowing capsules, necessitating the development of palatable liquid formulations. This study evaluated the bitter-masking efficacy of five flavoring agents: sirupus simplex FNA, sodium saccharin, magnesium sulphate, sodium gluconate and sodium glutamate. Also three NAM formulations were evaluated: (A) the base formulation containing 100 mg/mL NAM, pH 5 buffer (citric acid and disodium phosphate dihydrate), and 30% glycerine; (B) the base formulation with 50% (g/v) sirupus simplex FNA and (C) the base formulation with 0.25% (g/v) sodium saccharin. A taste test was conducted where adult participants evaluated formulations using a questionnaire, assessing basic taste, overall palatability and bitterness intensity. Among the five tested flavoring agents, 50% (g/v) sirupus simplex FNA and 0.25% (g/v) sodium saccharin demonstrated superior bitter-masking properties, resulting in a notable reduction in bitterness intensity and improved palatability compared to the 100 mg/mL NAM reference. The base formulation (A) significantly (p < 0.05) reduced bitterness intensity from moderate-to-strong to a moderate level. Further addition of either 50% (g/v) sirupus simplex FNA or 0.25% (g/v) sodium saccharin reduced the bitterness to a weak intensity; a statistically significant improvement (p < 0.05) compared to the reference formulation. Moreover, the inclusion of essences enhanced the tastefulness of the formulations. Given its lower risk of dental caries due to the absence of sugars, the 0.25% (g/v) sodium saccharin formulation (C) is the preferred candidate for chronic treatment regimens. These findings provide a basis for optimizing pediatric-friendly liquid NAM formulations.