A Rational Hierarchy to Capture Raw Material Attribute Variability in the Pharmaceutical Drug Product Development and Manufacturing Lifecycle.

Assessing the robustness of a drug product formulation and manufacturing process to variations in raw material (RM) properties is an essential aspect of pharmaceutical product development. Motivated by the need to demonstrate understanding of attribute-performance relationships at the time of new product registration and for subsequent process maintenance, we review practices to explore RM variations. We describe limitations that can arise when active ingredients and excipients invariably undergo changes during a drug product lifecycle. Historical approaches, such as Quality-by-Design (QbD) experiments, are useful for initial evaluations but can be inefficient and cumbersome to maintain once commercial manufacturing commences. The relatively miniscule data sets accessible in product development - used to predict response to a hypothetical risk of variation - become less relevant as real-world experience of actual variability in the commercial landscape grows. Based on our observations of development and manufacturing, we instead propose a holistic framework exploiting a hierarchy of RM variability, and challenge this with common failure modes. By explicitly incorporating higher ranking RM variations as perturbations, material-conserving experiments are shown to provide powerful and enduring robustness data. Case studies illustrate how correctly contextualizing such data in formulation and process development can avoid the traps of historical QbD approaches and become valuable for evaluating changes occurring later in the drug product lifecycle.

Implementation of a fully integrated continuous manufacturing line for direct compression and coating at a commercial pharmaceutical facility - Part 1: Operational considerations and control strategy.

We implement a fully integrated continuous manufacturing (CM) line for direct compression and coating of a pharmaceutical oral solid dosage form in a commercial production facility. In this first paper of a two-part series, we describe process design and operational choices made to introduce CM using infrastructure originally intended for batch operations. Consistent with lean manufacturing principles, we select equipment, facilities, and novel process analytical technologies that meet production agility goals alongside an existing batch process. Choices address process risks, are aligned with existing quality systems, yet allow exploration of CM agility benefits in commercial operations. We outline how operating procedures, control schemes, and release criteria from the historical batch process are adapted for CM with modified lot and yield definitions based on patient demand. We devise a hierarchy of complementary controls including real-time process interrogation, predictive residence time distribution models of tablet concentration, real-time product release testing using automated tablet NIR spectroscopy, active rejection and diversion, and throughput-based sampling. Results from lots produced under normal operational conditions confirm our CM process provides assurance of product quality. Qualification strategies to achieve lot size flexibility aims are also described. Finally, we consider CM extensions to formulations with differing risk profiles. Further analysis of results for lots produced under normal operational conditions is provided in part 2 (Rosas et al., 2023).

Implementation of a fully integrated CM direct compression and coating process at a commercial pharmaceutical facility - Part 2: PAT and RTD results for normal operational conditions batches.

This is the second of two articles detailing the continuous manufacturing (CM) development and implementation activities for an marketed product which have been realized in novel, qualified equipment, using validated control strategy elements to enable manufacture of batches under current good manufacturing practices (cGMP) and compliant with data integrity principles. Here, the application of process analytical technologies (PAT) and automation tools on batches produced under normal operational conditions is reviewed. The results from residence time distribution (RTD) models for predicting API concentration, in-line near infrared (NIR) testing of blend uniformity (BU) and at-line NIR spectroscopy analysis of core tablet concentration and tablet identity for real-time release testing (RTRT) are discussed. The influences of process equipment and design choices on NIR and RTD model variability, as well as the use of the PAT tools for monitoring the evolving properties understanding of CM process development, such as overcoming flow instabilities, is described. Results demonstrate that the RTD and NIR models developed and validated are robust to operating conditions and are critical for assuring steady state control of the continuous manufacturing process. Finally, the NIR and RTD model lifecycle, including procedures for necessary and normal model upgrades in a cGMP production environment, are presented.

Industry White Paper: Contemporary Opportunities and Challenges in Characterizing Crystallinity in Amorphous Solid Dispersions.

Members of the IQ Consortium ″Working Group on Characterization on Amorphous Solid Dispersions″ shares here a perspective on the analytical challenges, and limitations of detecting low levels of crystalline drug substance in amorphous solid dispersions (ASDs) and associated drug products. These companies aim to employ highly sensitive commercially available analytical technologies to guide development, support control strategies, and enable registration of quality products. We hope to promote consistency in development and registration approaches and guide the industry in development of "characterization best practices" in the interest of providing high quality products for patients. The first half of this perspective highlights the unique challenges of analytical methodologies to monitor crystalline drug substance in ASDs and their associated drug products. Challenges around use of limit tests, analyte spiking experiments, and method robustness are also underscored. The latter half describes the merits and limitations of the diverse analytical "toolbox" (such as XRPD, NIR and DSC), which can be readily applied during development and, in some cases, considered for potential application and validation in the commercial QC setting when necessary.

Dysregulated Diurnal Cortisol Pattern and Heightened Night-Time Cortisol in Individuals with Bipolar Disorder.

INTRODUCTION: Hypothalamic-pituitary-adrenal (HPA) axis dysregulation may contribute to the symptom burden in bipolar disorder (BD). Further characterization of cortisol secretion is needed to improve understanding of the connection between mood, sleep, and the HPA axis. Here, we observe diurnal cortisol patterns in individuals with BD and healthy controls (HCs) to determine time points where differences may occur. METHODS: Salivary cortisol was measured at 6 time points (wake, 15, 30, and 45 min after wake, between 2:00 and 4:00 p.m. and 10:00 p.m.) for 3 consecutive days in individuals with symptomatic BD (N = 27) and HC participants (N = 31). A general linear model with correlated errors was utilized to determine if salivary cortisol changed differently throughout the day between the 2 study groups. RESULTS: A significant interaction (F = 2.74, df = 5, and p = 0.02) was observed between the time of day and the study group (BD vs. HC) when modeling salivary cortisol over time, indicating that salivary cortisol levels throughout the day significantly differed between the study groups. Specifically, salivary cortisol in BD was elevated compared to HCs at the 10:00 p.m. time point (p = 0.01). CONCLUSION: Significantly higher levels of cortisol in participants with BD in the night-time suggest that the attenuation of cortisol observed in healthy individuals may be impaired in those with BD. Reregulation of cortisol levels may be a target of further study and treatment intervention for individuals with BD.

Small molecule drug screening in Drosophila identifies the 5HT2A receptor as a feeding modulation target.

Dysregulation of eating behavior can lead to obesity, which affects 10% of the adult population worldwide and accounts for nearly 3 million deaths every year. Despite this burden on society, we currently lack effective pharmacological treatment options to regulate appetite. We used Drosophila melanogaster larvae to develop a high-throughput whole organism screen for drugs that modulate food intake. In a screen of 3630 small molecules, we identified the serotonin (5-hydroxytryptamine or 5-HT) receptor antagonist metitepine as a potent anorectic drug. Using cell-based assays we show that metitepine is an antagonist of all five Drosophila 5-HT receptors. We screened fly mutants for each of these receptors and found that serotonin receptor 5-HT2A is the sole molecular target for feeding inhibition by metitepine. These results highlight the conservation of molecular mechanisms controlling appetite and provide a method for unbiased whole-organism drug screens to identify novel drugs and molecular pathways modulating food intake.

STAT1-independent control of a neurotropic measles virus challenge in primary neurons and infected mice.

Neurons are chiefly nonrenewable; thus, cytolytic immune strategies to clear or control neurotropic viral infections could have lasting neurologic consequences. IFN-γ is a potent antiviral cytokine that is critical for noncytolytic clearance of multiple neurotropic viral infections, including measles virus (MV); however, the downstream pathways through which IFN-γ functions in neurons have not been defined. Unlike most cell types studied to date in which IFN-γ affects gene expression via rapid and robust activation of STAT1, basal STAT1 levels in primary hippocampal neurons are constitutively low, resulting in attenuated STAT1 activation and consequently slower kinetics of IFN-γ-driven STAT1-dependent gene expression. Given this altered expression and activation of STAT1 in neurons, we sought to determine whether STAT1 was required for IFN-γ-mediated protection from infection in neurons. To do so, we evaluated the consequences of MV challenge of STAT1-deficient mice and primary hippocampal neurons explanted from these mice. Surprisingly, the absence of STAT1 did not restrict the ability of IFN-γ to control viral infection either in vivo or ex vivo. Moreover, the canonical IFN-γ-triggered STAT1 gene expression profile was not induced in STAT1-deficient neurons, suggesting that IFN-γ regulates neuronal STAT1-independent pathways to control viral replication.

Postinfectious myasthenia gravis: report of two children.

We report two children with transient myasthenia gravis preceded by viral illnesses. The first is a 5-year-old boy who developed oculobulbar weakness 2 weeks following a varicella-zoster infection. The second is a 4-year-old boy who developed facial diplegia and dysarthria several weeks following a viral pharyngitis. Myasthenia gravis was diagnosed based on the substantial decremental changes on 3 Hz repetitive motor nerve stimulation studies for the first child and on the positive edrophonium test and complete improvement in symptoms during pyridostigmine therapy for both children. In both cases, the symptoms gradually resolved and have not recurred following discontinuation of pyridostigmine. Molecular mimicry between the acetylcholine receptor and viral proteins might provide the nidus for the immune response in this variant of myasthenia gravis.

Facioscapulohumeral dystrophy presenting as infantile facial diplegia and late-onset limb-girdle myopathy in members of the same family.

We report a family with markedly variable myopathic weakness due to facioscapulohumeral muscular dystrophy (FSHD). The proband developed mild late-onset proximal limb weakness. Her two daughters had severe infantile facial diplegia, initially diagnosed as Möbius syndrome, and mild childhood-onset limb weakness and scapular winging. Results of facial muscle electromyography and muscle histopathology supported a myopathic disorder. This case study further highlights the broad clinical spectrum and intrafamily variability in FSHD, and the occasional absence of a positive correlation between fragment size and disease onset. Moreover, this study underscores the importance of considering FSHD in cases of infantile facial diplegia, especially in patients not demonstrating the full clinical features of Möbius syndrome. In difficult cases, facial muscle electromyography may help to differentiate myopathic from neuropathic weakness, and help guide further diagnostic studies.

A Taylor vortex analogy in granular flows.

Fluids sheared between concentric rotating cylinders undergo a series of three-dimensional instabilities. Since Taylor's archetypal 1923 study, these have proved pivotal to understanding how fluid flows become unstable and eventually undergo transitions to chaotic or turbulent states. In contrast, predicting the dynamics of granular systems--from nano-sized particles to debris flows--is far less reliable. Under shear these materials resemble fluids, but solid-like responses, non-equilibrium structures and segregation patterns develop unexpectedly. As a result, the analysis of geophysical events and the performance of largely empirical particle technologies might suffer. Here, using gas fluidization to overcome jamming, we show experimentally that granular materials develop vortices consistent with the primary Taylor instability in fluids. However, the vortices observed in our fluidized granular bed are unlike those in fluids in that they are accompanied by novel mixing-segregation transitions. The vortices seem to alleviate increased strain by spawning new vortices, directly modifying the scale of kinetic interactions. Our observations provide insights into the mechanisms of shear transmission by particles and their consequent convective mixing.

Structure and dynamics of a dihydrogen/hydride ansa molybdenocene complex.

In contrast to [Cp(2)MoH(3)](+), which is a thermally stable trihydride complex, the ansa-bridged analogue [(eta-C(5)H(4))(2)CMe(2)MoH(H(2))](+) (1) is a thermally labile dihydrogen/hydride complex. Partial deuteration of the hydride ligands allows observation of J(H)(-)(D) = 11.9 Hz in 1-d(1) and 9.9 Hz in 1-d(2) (245 K), indicative of a dihydrogen/hydride structure. There is a slight preference for deuterium to concentrate in the dihydrogen ligand. A rapid dynamic process interchanges the hydride and dihydrogen moieties in complex 1. Low temperature (1)H NMR spectra of 1 give a single hydride resonance, which broadens at very low temperature due to rapid dipole-dipole relaxation (T(1) = 23 ms (750 MHz, 175 K) for the hydride resonance in 1). Low temperature (1)H NMR spectra of 1-d(2) allow the observation of decoalescence at 180 K into two resonances. The bound dihydrogen ligand exhibits hindered rotation with DeltaG(150) = 7.4 kcal/mol, but H atom exchange is still rapid at all accessible temperatures (down to 130 K). Density functional calculations confirm the dihydrogen/hydride structure as the ground state for the molecule and give estimates for the energy of two hydrogen exchange processes in good agreement with experiment. The presence of the C ansa bridge is shown to decrease the ability of the metallocene fragment to donate to the hydrogens, thus stabilizing the (eta(2)-H(2)) unit and modulating the barrier to H(2) rotation.

Free surface waves in wall-bounded granular flows.

We report free-surface waves in granular flows near boundaries in an inclined chute. The chevron-shaped traveling waves spontaneously develop at inclinations close to the angle of repose for both steady and accelerating flows. Two distinct regimes are characterized by internal angle and frequency variations. Experimental measurements indicate that subsurface circulation driven by velocity gradients near frictional walls plays a central role in the pattern formation mechanism, suggesting that wave generation is controlled by the granular analog of a fluid boundary layer.