Search

Complex generics are generic versions of drug products that generally have complex active ingredients, complex formulations, complex routes of delivery, complex dosage forms, are complex drug-device combination products, or have other characteristics that can make it complex to demonstrate bioequivalence or to develop as generics. These complex products (i.e. complex generics) are an important element of the United States (U.S.) Food and Drug Administration’s (FDA’s) Generic Drug User Fee Amendments (GDUFA) II Commitment Letter. The Center for Research on Complex Generics (CRCG) was formed by a grant from the FDA to address challenges associated with the development of complex generics. To understand these challenges, the CRCG conducted a “Survey of Scientific Challenges in the Development of Complex Generics”. The three main areas of questioning were directed toward which (types of) complex products, which methods of analysis to support a demonstration of bioequivalence, and which educational topics the CRCG should prioritize. The survey was open to the public on a website maintained by the CRCG. Regarding complex products, the top three selections were complex injectables, formulations, and nanomaterials; drug-device combination products; and inhalation and nasal products. Regarding methods of analysis, the top three selections were locally-acting physiologically-based pharmacokinetic modeling; oral absorption models and bioequivalence; and data analytics and machine learning. Regarding educational topics, the top three selections were complex injectables, formulations, and nanomaterials; drug-device combination products; and data analytics, including quantitative methods and modeling & simulation. These survey results will help prioritize the CRCG’s initial research and educational initiatives. Supplementary Information The online version contains supplementary material available at 10.1007/s11095-021-03149-y.

A patient was denoted to be generic brittle (GB) if they had a negative opinion about generics (e.g. prior history of a switch problem) or took the innovator brand of their most problematic anti-epileptic drug (AED) when generic was available. The aim of this hypothesis-generating study was to assess possible genetic and physiologic differences between GB and not GB patients with epilepsy. Patients (n = 148) with epilepsy were previously characterized as being either GB or not GB. Blood was collected from each subject for genotyping and physiologic testing. Genotyping for 24 single nucleotide polymorphisms (SNPs) and two copy number variants (CNVs) was performed across 12 genes in each patient. Forty-four physiologic tests were conducted in each patient. Chi square analysis was performed to assess for associations between genotyping results and GB status, as well as between physiologic test results and GB status. No SNP or CNV discriminated GB status in genetic analysis (genotype or allele frequency). Physiologic test results in this study were not associated with GB status. Questions from neurologists and patients about generics is frequently based on applicability of generic drug standards to individual subjects. However, findings here in patients with epilepsy did not uncover genetic or physiologic reasons that explained which patients were GB and which were not GB.

Purpose Currently, the FDA allows biowaivers for Class I (high solubility and high permeability) and Class III (high solubility and low permeability) compounds of the Biopharmaceutics Classification System (BCS). Scientific evidence should be provided to support biowaivers for BCS Class I and Class III (high solubility and low permeability) compounds. Methods Data on the effects of excipients on drug permeability are needed to demonstrate that commonly used excipients do not affect the permeability of BCS Class III compounds, which would support the application of biowaivers to Class III compounds. This study was designed to generate such data by assessing the permeability of four BCS Class III compounds and one Class I compound in the presence and absence of five commonly used excipients. Results The permeability of each of the compounds was assessed, at three to five concentrations, with each excipient in two different models: Caco-2 cell monolayers, and in situ rat intestinal perfusion. No substantial increases in the permeability of any of the compounds were observed in the presence of any of the tested excipients in either of the models, with the exception of disruption of Caco-2 cell monolayer integrity by sodium lauryl sulfate at 0.1 mg/ml and higher. Conclusion The results suggest that the absorption of these four BCS Class III compounds would not be greatly affected by the tested excipients. This may have implications in supporting biowaivers for BCS Class III compounds in general.

Purpose. The acidic microclimate in poly(D, L-lactide-co-glycolide) 50/50 microspheres has been previously demonstrated by our group as the primary instability source of encapsulated bovine serum albumin (BSA). The objectives of this study were to stabilize the encapsulated model protein, BSA, and to achieve continuous protein release by using a blend of: slowly degrading poly(D, L-lactide) (PLA), to reduce the production of acidic species during BSA release; and pore-forming poly(ethylene glycol) (PEG), to increase diffusion of BSA and polymer degradation products out of the polymer. Methods. Microspheres were formulated from blends of PLA (Mw 145,000) and PEG (Mw 10,000 or 35,000) by using an anhydrous oil-in-oil emulsion and solvent extraction (O/O) method. The polymer blend composition and phase miscibility were examined by FT-IR and DSC, respectively. Microsphere surface morphology, water uptake, and BSA release kinetics were also investigated. The stability of BSA encapsulated in microspheres was examined by losses in protein solubility, SDS-PAGE, IEF, CD, and fluorescence spectroscopy. Results. PEG was successfully incorporated in PLA microspheres and shown to possess partial miscibility with PLA. A protein loading level of 5% (w/w) was attained in PLA/PEG microspheres with a mean diameter of approximately 100 μm. When PEG content was less than 20% in the blend, incomplete release of BSA was observed with the formation of insoluble, and primarily non-covalent aggregates. When 20%-30% PEG was incorporated in the blend formulation, in vitro continuous protein release over 29 days was exhibited. Unreleased BSA in these formulations was water-soluble and structurally intact. Conclusions. Stabilization and controlled relaease of BSA from PLA/PEG microspheres was achieved due to low acid and high water content in the blend formulation.