Development and Validation of Matrix of Chemistry, Manufacturing, and Control (MoCMC) System for Intramammary Drug Products (IMM)

PURPOSE

Products formulated for intramammary (IMM) infusion are intended for the delivery of therapeutic moieties directly into the udder through the teat canal to maximize drug exposure at the targeted clinical site, the mammary gland, with little to no systemic drug exposure. Currently, to our knowledge, there has been no in-vitro matrix system available to differentiate between IMM formulations. Our goal is to develop A custom tailored in-vitro "Matrix of Chemistry, Manufacturing and Control" (MoCMC) System to be a promising future tool for identifying inequivalent IMM formulations. MoCMC can detect inter and intra batch variabilities, thereby identifying potential generics versus brand product similarities or differences with a single numeric value and a specific & distinctive fingerprint.

METHODS

The FDA-approved IMM formulation, SPECTRAMASTⓇ LC, was selected as the reference product for the MoCMC. Twelve in-house test formulations containing ceftiofur hydrochloride were formulated and characterized. The MoCMC was developed to include six input parameters and three output parameters. The MoCMC system was used to evaluate and compare SPECTRAMASTⓇ LC with its in-house formulations.

RESULTS

Based on the MoCMC generated parameters, the distinctive fingerprints of MoCMC for each IMM formulations, and the statistical analyses of MCI and PPI values, in-house formulations, F-01 and F-02 showed consistency while the rest of in-house formulations (F-03-F-12) were significantly different as compared to SPECTRAMASTⓇ LC.

CONCLUSION

This research showed that the MoCMC approach can be used as a tool for intra batch variabilities, generics versus brand products comparisons, post-approval formulations changes, manufacturing changes, and formulation variabilities.

Innovations and Patent Trends in the Development of USFDA Approved Protein Kinase Inhibitors in the Last Two Decades

Protein kinase inhibitors (PKIs) are important therapeutic agents. As of 31 May 2021, the United States Food and Drug Administration (USFDA) has approved 70 PKIs. Most of the PKIs are employed to treat cancer and inflammatory diseases. Imatinib was the first PKI approved by USFDA in 2001. This review summarizes the compound patents and the essential polymorph patents of the PKIs approved by the USFDA from 2001 to 31 May 2021. The dates on the generic drug availability of the PKIs in the USA market have also been forecasted. It is expected that 19 and 48 PKIs will be genericized by 2025 and 2030, respectively, due to their compound patent expiry. This may reduce the financial toxicity associated with the existing PKIs. There are nearly 535 reported PKs. However, the USFDA approved PKIs target only about 10-15% of the total said PKs. As a result, there are still a large number of unexplored PKs. As the field advances during the next 20 years, one can anticipate that PKIs with many scaffolds, chemotypes, and pharmacophores will be developed.

[Effect of Shelf Life on the Physical Stability of Suspended Ophthalmic Solutions]

Quality changes associated with physical changes in suspended eye drops are difficult to predict. In this study, we attempted to evaluate the aggregation and redispersability in commercially available suspended eye drops (fluorometholone ophthalmic solutions). The 0.1% fluorometholone ophthalmic solutions (the original product and 4 generic products) were gently mixed by hand after short-term (4 months) or long-term (40 months) storage, and the drug concentration in the first drop and physical stability (redispersability and particle size) were measured. All eye drops produced a cloudy precipitate on the bottom surface of the container, and the amount of precipitate decreased with mixing time. The drug concentration per drop in the original product was approximately 70% of the labeled value after mixing 10 times, and the drug particle size was approximately 4 μm. After mixing the generic products stored short-term 10 times, the concentration ranged from less than 50% to almost 100%. In addition, some generic products after long-term storage had a reduced redispersion ability and labeled concentration. These results suggested that at least 10 mixing were required before the using of fluorometholone original product. In addition, some generic products may not provide sufficient drug exposure even when mixed in the same manner as the original products.

Evaluation of Dissolution Profile between Original and Generic Products of Zolpidem Tartrate by Microdialysis-HPLC

The evaluation of the dissolution profile of hypnotic drugs is important to promote switching from original products to generic products by removing distrust in generic hypnotics. In this study, we investigated differences in the dissolution profiles between original and generic products (GE-D, GE-S, and GE-T) in commercially available zolpidem tartrate (ZOL) products using the HPLC method using a connected microdialysis probe (microdialysis-HPLC method). Although the degree of hardness and the disintegration time were not different among the original, GE-S, and GE-T, GE-D was 1.4 times harder than the other products. The disintegration time of GE-D was approximately twice as long as that of the original product. Generic products dissolved rapidly as compared with the original product, however, the dissolution rate in the ZOL powder (milled ZOL product) was not different between the original and generic products. Macrogol 6000 (polyethylene glycol (PEG)-6000) was used in the generic products, and this additive was the only PEG difference from the original product. We investigated whether the PEG in the product affected the solubility of ZOL and found that the addition of PEG-4000 or PEG-6000 significantly increased the dissolution rate. These results suggest that the solubility of ZOL may be increased by PEG when the product is disintegrated, resulting in the increased dissolution rate in the generic products. In conclusion, we found that the difference of PEG affected the dissolution profile in the disintegration process using the microdialysis-HPLC method. This finding can help ensure the safety of milled products and the selection of additives.

Inhibition of Gastric H+,K+-ATPase Activity in Vitro by Dissolution Media of Original Brand-Name and Generic Tablets of Lansoprazole, a Proton Pump Inhibitor

To investigate the inhibitory effect of a commercial proton pump inhibitor (lansoprazole) on the gastric proton pump H⁺,K⁺-ATPase in vitro, we used orally disintegrating (OD) tablets including original brand-name and generic tablets. In the course of the development of generic products, dissolution and clinical tests are necessary to ensure their bioequivalence to the original brand-name products; by contrast, there is almost no opportunity to demonstrate their activity in vitro. This study initially compared the similarity of the dissolution of test generic tablets with that of the original brand-name tablets. The dissolution tests for 15 and 30-mg lansoprazole tablets found their dissolution properties were similar. Subsequently, the dissolution media were sampled and then their effects on the H⁺,K⁺-ATPase activity were measured using tubulovesicles prepared from the gastric mucosa of hogs. We confirmed that the inhibitory effects of the generic tablets on H⁺,K⁺-ATPase activity were consistent with those of the original brand-name tablets. Furthermore, lansoprazole contents in each tablet estimated from their inhibitory effects were in good agreement with their active pharmaceutical ingredient content. To our knowledge, this is the first technical report to compare the in vitro biochemical activity of lansoprazole OD tablets between the original brand-name and generic commercial products.

Comparison of Dissolution Similarity Assessment Methods for Products with Large Variations: f2 Statistics and Model-Independent Multivariate Confidence Region Procedure for Dissolution Profiles of Multiple Oral Products

The current Japanese Ministry of Health Labour and Welfare (MHLW)'s Guideline for Bioequivalence Studies of Generic Products uses averaged dissolution rates for the assessment of dissolution similarity between test and reference formulations. This study clarifies how the application of model-independent multivariate confidence region procedure (Method B), described in the European Medical Agency and U.S. Food and Drug Administration guidelines, affects similarity outcomes obtained empirically from dissolution profiles with large variations in individual dissolution rates. Sixty-one datasets of dissolution profiles for immediate release, oral generic, and corresponding innovator products that showed large variation in individual dissolution rates in generic products were assessed on their similarity by using the f₂ statistics defined in the MHLW guidelines (MHLW f₂ method) and two different Method B procedures, including a bootstrap method applied with f₂ statistics (BS method) and a multivariate analysis method using the Mahalanobis distance (MV method). The MHLW f₂ and BS methods provided similar dissolution similarities between reference and generic products. Although a small difference in the similarity assessment may be due to the decrease in the lower confidence interval for expected f₂ values derived from the large variation in individual dissolution rates, the MV method provided results different from those obtained through MHLW f₂ and BS methods. Analysis of actual dissolution data for products with large individual variations would provide valuable information towards an enhanced understanding of these methods and their possible incorporation in the MHLW guidelines.

Key Technical Aspects Influencing the Accuracy of Tablet Subdivision

Tablet subdivision is a common practice used mainly for dose adjustment. The aim of this study was to investigate how the technical aspects of production as well as the method of tablets subdivision (employing a tablet splitter or a kitchen knife) influence the accuracy of this practice. Five drugs commonly used as subdivided tablets were selected. For each drug, the innovator drug product, a scored-generic and a non-scored generic were investigated totalizing fifteen drug products. Mechanical and physical tests, including image analysis, were performed. Additionally, comparisons were made between tablet subdivision method, score, shape, diluent composition and coating. Image analysis based on surface area was a useful tool as an alternative assay to evaluate the accuracy of tablet subdivision. The tablet splitter demonstrates an advantage relative to a knife as it showed better results in weight loss and friability tests. Oblong, coated and scored tablets had better results after subdivision than round, uncoated and non-scored tablets. The presence of elastic diluents such as starch and dibasic phosphate dehydrate conferred a more appropriate behaviour for the subdivision process than plastic materials such as microcrystalline cellulose and lactose. Finally, differences were observed between generics and their innovator products in all selected drugs with regard the quality control assays in divided tablet, which highlights the necessity of health regulations to consider subdivision performance at least in marketing authorization of generic products.

Pharmacokinetic equivalence study of two formulations of the anticonvulsant pregabalin

Purpose

The present study was conducted to evaluate whether the bioavailability of pregabalin capsules 150 mg manufactured by PT Dexa Medica was equivalent to the reference formulation.

Methods

This was a randomized, open-label, two-period, two-sequence, and crossover study under fasting condition, with a 1-week washout period. Plasma concentrations of pregabalin from 20 subjects were determined by using a validated liquid chromatography with tandem mass spectrometry (LC-MS/MS) detection method. Pharmacokinetic parameters assessed in this study were: area under the plasma concentration–time curve from time zero to last observed quantifiable concentration (AUC_0–t), area under the plasma concentration–time curve from time zero to infinity (AUC_0–∞), maximum plasma concentration (C_max), time to maximum plasma concentration (t_max), and terminal half-life (t_1/2). The 90% confidence intervals (CIs) for the geometric mean ratios of test formulation/reference formulation were calculated for the AUC and C_max parameters; while t_max difference was analyzed nonparametrically on the original data using the Wilcoxon matched-pairs test, and t_1/2 difference was analyzed using Student’s paired t-test.

Results

The mean (standard deviation [SD]) AUC_0–t, AUC_0–∞, C_max, and t_1/2 of pregabalin from the test formulation were 27,845.86 (4,508.27) ng · h/mL, 28,311.70 (4,790.55) ng · h/mL, 3,999.71 (801.52) ng/mL, and 5.66 (1.20) hours, respectively; while the mean (SD) AUC_0–t, AUC_0–∞,C_max, and t_1/2 of pregabalin from the reference formulation were 27,398.12 (4,266.28) ng · h/mL, 27,904.24 (4,507.31) ng · h/mL, 3,849.50 (814.50) ng/mL, and 5.87 (1.25) hours, respectively. The median (range) t_max of pregabalin from the test formulation and reference formulation was 1.00 (0.67–2.00) hours and 1.00 (0.67–3.00) hours, respectively. The 90% CIs for the geometric mean ratios of test formulation/reference formulation for pregabalin were 101.54% (98.75%–104.41%) for AUC_0–t, 101.35% (98.66%–104.11%) for AUC_0–∞, and 104.19% (98.75%–109.93%) for C_max.

Conclusion

The study concluded that the two formulations of pregabalin capsules studied were bioequivalent.