Since their introduction to pharmacotherapy, proton pump inhibitors (PPIs) have been widely used in the treatment of numerous diseases manifested by excessive secretion of gastric acid. Despite that, there are still unmet needs regarding their availability for patients of all age groups. Their poor stability hinders the development of formulations in which dose can be easily adjusted. The aim of this review is to describe the discovery and development of PPIs, discuss formulation issues, and present the contemporary solutions, possibilities, and challenges in formulation development. The review outlines the physicochemical characteristics of PPIs, connects them with pharmacokinetic and pharmacodynamic properties, and describes the stability of PPIs, including the identification of the most important factors affecting them. Moreover, the possibilities for qualitative and quantitative analysis of PPIs are briefly depicted. This review also characterizes commercial preparations with PPIs available in the US and EU. The major part of the review is focused on the presentation of the state of the art in the development of novel formulations with PPIs covering various approaches employed in this process: nanoparticles, microparticles, minitablets, pellets, bilayer, floating, and mucoadhesive tablets, as well as parenteral, transdermal, and rectal preparations. It also anticipates further possibilities in the development of PPIs dosage forms. It is especially addressed to the researchers developing new formulations containing PPIs, since it covers the most important formulary issues that need to be considered before a decision on the selection of the formula is made. It may help in avoiding unnecessary efforts in this process and choosing the best approach. The review also presents an up-to-date database of publications focused on the pharmaceutical technology of formulations with PPIs.

Orodispersible films (ODFs) address the needs of pediatric and geriatric patients and people with swallowing difficulties due to fast disintegration in the mouth. Typically, they are obtained using the solvent casting method, but other techniques such as 3D printing and electrospinning have already been investigated. The decision on the manufacturing method is of crucial importance because it affects film properties. This study aimed to compare electrospun ODFs containing aripiprazole and polyvinyl alcohol with films prepared using casting and 3D printing methods. Characterization of films included DSC and XRD analysis, microscopic analysis, the assessment of mechanical parameters, disintegration, and dissolution tests. Simplified stability studies were performed after one month of storage. All prepared films met acceptance criteria for mechanical properties. Electrospun ODFs disintegrated in 1.0 s, which was much less than in the case of other films. Stability studies have shown the sensitivity of electrospun films to the storage condition resulting in partial recrystallization of ARP. These changes negatively affected the dissolution rate, but mechanical properties and disintegration time remained at a desirable level. The results demonstrated that electrospun fibers are promising solutions that can be used in the future for the treatment of patients with swallowing problems.

The compendial method of evaluation of orodispersible tablets (ODT) is the same disintegration test as for conventional tablets. Since it does not reflect the disintegration process in the oral cavity, alternative methods are proposed that are more related to in vivo conditions, e.g. modified dissolution paddle apparatus, texture analyzer, rotating shaft apparatus, CCD camera application, or wetting time and water absorption ratio measurement. In this study, three different co-processed excipients for direct compression of orally disintegrating tablets were compared (Ludiflash, Pharmaburst, F-Melt). The properties of the prepared tablets such as tensile strength, friability, wetting time and water absorption ratio were evaluated. Disintegration time was measured using the pharmacopoeial method and the novel apparatus constructed by the authors. The apparatus was based on the idea of Narazaki et al., however it has been modified. Magnetic resonance imaging (MRI) was applied for the analysis of the disintegration mechanism of prepared tablets. The research has shown the significant effect of excipients, compression force, temperature, volume and kind of medium on the disintegration process. The novel apparatus features better correlation of disintegration time with in vivo results (R² = 0.9999) than the compendial method (R² = 0.5788), and presents additional information on the disintegration process, e.g. swelling properties.

Even that orodispersible tablets (ODTs) have been successfully used in therapy for more than 20 years, there is still no compendial method of their disintegration time evaluation other than the pharmacopoeial disintegration test conducted in 800-900 mL of distilled water. Therefore, several alternative tests more relevant to in vivo conditions were described by different researchers. The aim of this study was to compare these methods and correlate them with in vivo results. Six series of ODTs were prepared by direct compression. Their mechanical properties and disintegration times were measured with pharmacopoeial and alternative methods and compared with the in vivo results. The highest correlation with oral disintegration time was found in the case of own-construction apparatus with additional weight and the employment of the method proposed by Narazaki et al. The correlation coefficients were 0.9994 (p < 0.001), and 0.9907 (p < 0.001) respectively. The pharmacopoeial method correlated with the in vivo data much worse (r = 0.8925, p < 0.05). These results have shown that development of novel biorelevant methods of ODT's disintegration time determination is eligible and scientifically justified.

Purpose: Orodispersible tablets (orally disintegrating tablets, ODTs) have been used in pharmacotherapy for over 20 years since they overcome the problems with swallowing solid dosage forms. The successful formula manufactured by direct compression shall ensure acceptable mechanical strength and short disintegration time. Our research aimed to develop ODTs containing bromhexine hydrochloride suitable for registration in accordance with EMA requirements. Methods: We examined the performance of five multifunctional co-processed excipients, i.e., F-Melt® C, F-Melt® M, Ludiflash®, Pharmaburst® 500 and Prosolv® ODT G2 as well as self-prepared physical blend of directly compressible excipients. We tested powder flow, true density, compaction characteristics and tableting speed sensitivity. Results: The manufacturability studies confirmed that all the co-processed excipients are very effective as the ODT formula constituents. We noticed superior properties of both F-Melt’s®, expressed by good mechanical strength of tablets and short disintegration time. Ludiflash® showed excellent performance due to low works of plastic deformation, elastic recovery and ejection. However, the tablets released less than 30% of the drug. Also, the self-prepared blend of excipients was found sufficient for ODT application and successfully transferred to production scale. Outcome of the scale-up trial revealed that the tablets complied with compendial requirements for orodispersible tablets. Conclusions: We proved that the active ingredient cannot be absorbed in oral cavity and its dissolution profiles in media representing upper part of gastrointestinal tract are similar to marketed immediate release drug product. In our opinion, the developed formula is suitable for registration within the well-established use procedure without necessity of bioequivalence testing.