Acceptability of flavoured pharmaceutically non-active mini-tablets in pet cats tested with a rapid 3-portal acceptance test with and without food

The challenge of downstream processing of spray dried amorphous solid dispersions into minitablets designed for the paediatric population - A sustainable product development approach

Poorly water-soluble drugs present a significant challenge in the development of oral solid dosage forms (OSDs). In formulation development the appropriate use of excipients to adjust solubility, and the choice of manufacturing method and pharmaceutical processes to obtain a dosage form to meet the needs of the patient group, is crucial. Preparing an amorphous solid dispersion (ASD) is a well-established method for solubility enhancement, and spray drying (SD) a common manufacturing method. However, the poor flowability of spray dried materials poses a significant challenge for downstream processing. Promoting sustainability in OSD development involves embracing a versatile formulation design, which enables a broader spectrum of patients to use the product, as opposed to altering existing dosage forms retrospectively. The objective of the current study was to develop a formulation of spray dried indomethacin ASD suited to the production, by direct compression, of instant release paediatric minitablets. Excipients evaluated were PVP or HPMCAS in solid dispersions at the preformulation phase, and MCC and lactose as a filler in direct compression. From the studied formulations, a 3:1 ratio blend of Vivapur 200/Pharmatose 200 M (MCC/lactose) with 0.5% (w/w) magnesium stearate was found to be the most promising in tableting, and minitablets containing a 6.22% content of spray-dried ASD of indomethacin/PVP K 29-32 could be obtained with desired tablet hardness and pharmaceutical quality, complying with tests of weight variation and fast disintegration in an aqueous environment. As a case example, this study provides a good foundation for further studies in harnessing a sustainable approach to the development of pharmaceutical formulations that can appropriately serve different patient sub-populations.

Use of 2-hydroxy-4-(methylthio)-butanoic acid to inhibit Salmonella and Listeria in raw meat for feline diets and palatability in domestic cats

While the raw pet food market continues to grow, the risk of bacterial contamination in these types of diets is a major concern, with Salmonella enterica and Listeria monocytogenes being the most frequently associated pathogens in raw pet food product recalls. dl-Methionine is included in some commercial feline kibble and canned diets to improve protein quality; however, an alternative to this is a liquid methionine supplement, 2-hydroxy-4-(methylthio)-butanoic acid (HMTBa), which is also an organic acid. 2-Hydroxy-4-(methylthio)-butanoic acid has previously demonstrated similar efficacy to formic acid against pathogens in a liquid environment and may be a good candidate to inhibit S. enterica and L. monocytogenes in raw ground meat. First, the minimum inhibitory concentration and minimum bactericidal concentration of HMTBa against these pathogens under laboratory growth conditions were determined by measuring growth of pathogens over 36 h when exposed to 10 concentrations of HMTBa (0.10% to 1.00%) mixed with tryptic soy broth. 2-Hydroxy-4-(methylthio)-butanoic acid included at ≥0.50% was bactericidal to S. enterica and L. monocytogenes (P < 0.05). Next, five levels of HMTBa (0.50% to 1.25%) were included in raw ground meat mixtures inoculated with cocktails of S. enterica or L. monocytogenes, and contamination levels were determined at four timepoints: immediately, and after refrigerated storage (4 °C) at 24, 48, and 72 h after removal from freezer (24 h at -20 °C). 2-Hydroxy-4-(methylthio)-butanoic acid included as 1.25% of the meat mixture reduced S. enterica and L. monocytogenes compared with the control (P < 0.05); however, it did not result in total kill of either of these pathogens. Following this, feeding behaviors of seven domestic cats were assessed when offered a raw chicken diet treated with or without 1.25% HMTBa for 5 d each, after which a 2-d 2-choice preference test was conducted. Cats demonstrated a preference for raw diets without HMTBa, but still readily consumed diets with 1.25% HMTBa, suggesting that such a diet was still palatable to them.

Elucidating the Splitting Behavior of Tablets to Optimize the Pharmacotherapy in Veterinary Medicine

It is well known that the splitting of tablets can bring serious risks to the health of the treated animals, e.g., the possible adverse reactions caused by overdoses of fenbendazole or aspirin. In this regard, this work aimed to evaluate, for the first time, the splitting behavior of commercial veterinary tablets and identifying the technological aspects that interfere in this process. Tablets were cut in halves using a tablet splitter and were analyzed regarding mass variation, mass loss, friability, and hardness. Microstructural and morphological evaluations were also performed. For most of the tablets, organic flavor additives provided more uniformity and cohesive matrix, which preserved its hardness after the cut and led to subdivision results within acceptable limits for mass measurements and friability. Apart from the microstructure, the most critical technological aspect for a correct splitting performance in such tablets was the presence of a score. Thus, the results presented here allow us to guide the manufacturing of veterinary drug products in order to produce tablets more adapted to the splitting process.

Development and Evaluation of Feline Tailored Amlodipine Besylate Mini-Tablets Using L-lysine as a Candidate Flavouring Agent

Felines may find orally administered medicines unpalatable, thus presenting a problem in the treatment of chronic conditions such as hypertension, a commonly diagnosed condition in felines requiring daily administration of medication. A pertinent example is amlodipine besylate, formulations of which are known to be poorly tolerated by cats. There is therefore a need to develop feline-specific delivery approaches that are both simple to administer and mask the taste of the drug, thereby enhancing the owner's commitment to treatment and the associated therapeutic outcome for the companion animal. In addition, it is helpful to develop accessible and reproducible means of assessing taste for pre-clinical selection, hence the use of recently developed taste biosensor systems for veterinary applications is an area of interest. This study focuses on developing feline-specific amlodipine besylate formulations by improving the taste using a suitable flavouring agent while reducing dosage form size to a 2 mm diameter mini-tablet. The choice of L-lysine as a flavouring agent was based on the dietary and taste preference of cats. The impact of L-lysine on the taste perception of the formulation was evaluated using a biosensor system (E-tongue) fitted with sensors sensitive to bitter tastes. The results showed L-lysine successfully masked bitterness, while the drug release studies suggest that it has no impact on drug dissolution. In addition, tableting parameters such as tablet mass uniformity, content uniformity, tablet diameter, thickness and hardness were all satisfactory. The present study suggests that amlodipine besylate mini-tablets containing L-lysine could improve the palatability and in turn support product acceptability and ease of administration. These data could have an impact on orally administered medicines for cats and other veterinary species through product differentiation and competitive advantage in the companion animal market sector. The study also outlines the use of the electronic tongue as a tool for formulation selection in the veterinary field.

Factors affecting the results of food preference tests in cats

The aim of this study was to (i) gain an overview of the protocols of food preference tests in cats through a systematic review, (ii) assess the effects of test duration, time of day, and sex, and (iii) propose a statistical approach based on power analysis to determine sample size and analyze the results. The manuscripts included in this review had marked variations in the number of days (2-56), sample size (9-60 cats), feeding times (2.5-1440 min), and number of meals per day (1-2) during the test. Additionally to the literature review, three palatability tests (lasting 10 days each) were conducted with 40 cats (22 males and 18 females, 1.8 ± 0.16 years, 3.73 ± 0.90 kg) to assess the effects of test duration, time of day, and gender on the results. From the second day of the test, the sensitivity of the results was higher, because on the first day the results in one of the tests differed from the others (p = .0058). There was no difference (p > .05) between times of day (morning vs afternoon) or gender (males vs females) on the results of the feed intake ratio. For a SD of 0.20, p < .05, and delta of 0.10, the minimum number of cats for two-bowl assays is 23 (test power higher than 0.75).The sample size and test duration are critical factors in the decision making by the investigators about the design of food preference tests in cats. The use of a power test is recommended upon planning a food preference test protocol in cats.