Root Cause Analysis of An Inverse Relationship Between The Ice Nucleation Temperature, Process Efficiency And Quality of A Lyophilized Product.

The aim of this study was to probe an unexpected relationship between the ice nucleation temperature (TIN), process efficiency and product attributes in a controlled ice nucleation (CIN) lyophilization process. An amorphous product was lyophilized with (CIN-5 °C, CIN-7 °C or CIN-10 °C) or without (NOCIN) control of ice nucleation. Process parameters and product attributes were monitored and compared using a series of advanced in-line and off-line process analytical technology (PAT) tools. Unexpectedly, an indirect relationship was observed between TIN and primary drying efficiency for the CIN processes. Further, the CIN-5 °C process was associated with higher product resistance to mass flow than corresponding CIN-7 °C and CIN-10 °C processes. Surprisingly, the air voids in some NOCIN products were larger than CIN-5 °C products but comparable to CIN-7 °C. Heat flux analysis revealed an indirect relationship between TIN and the minimum hold time required to complete solidification. The heat flux analysis also revealed all products underwent complete solidification prior to primary drying. The order of homogeneity in water activity of the products was CIN-5 °C ≥NOCIN>CIN-7 °C. The higher homogeneity in water activity of CIN-5 °C than corresponding CIN-7 °C processes indicated that the lower process efficiency of CIN-5 °C could not be attributed to unsuccessful induction of ice nucleation during CIN-5 °C. High resolution micro-CT imaging and Artificial Intelligence Image analysis revealed cake wall deformation in CIN-7 °C and NOCIN products but not in CIN-5 °C. In addition, NOCIN products had bimodal distribution in air voids with median size range of 4-5 µm and 151.9-309 µm, respectively, hence the lower process efficiency of NOCIN despite the higher D90. Thus, the observed relationship between TIN and process efficiency may be attributed to microstructural changes post freezing. This hypothesis was corroborated by visible macroscopic cake collapse in NOCIN products but not in CIN products after lyophilization at a higher shelf temperature. In conclusion, the advantages of controlling the ice nucleation temperature of a lyophilization process may only be attained through a robust process design that takes into consideration the primary and secondary drying process parameters. Further, combined use of advanced in-line and off-line PAT tools for process and product characterization may hasten the at scale adoption of advance techniques such as CIN.

Effect of formulation and peptide folding on the fibrillar aggregation, gelation, and oxidation of a therapeutic peptide.

The physical and chemical stability of therapeutic peptides presents challenges in developing robust formulations. The stability of the formulation affects product safety, efficacy and quality. Therefore, an understanding of the effects of formulation variables on the peptide's conformational structure and on its possible physical and chemical degradation is vital. To this end, computational and experimental analysis were employed to investigate the impact of formulation, peptide folding and product handling on oxidation, fibrillar aggregation and gelation of teriparatide. Teriparatide was used as a model drug due to the correlation of its conformation in solution with its pharmacological activity. Fibrillar aggregation and gelation were monitored using four orthogonal techniques. An innovative, automated platform coupled with ion mobility mass spectrometry was used for profiling chemical degradants. Increases in teriparatide concentration, pH, and ionic strength were found to increase the rate of fibrillar aggregation and gelation. Conversely, an increase in peptide folding and stabilization of the folded structures was found to decrease the rate of fibrillar aggregation and gelation. Moreover, the rate of oxidation was found to be inversely related to its solution concentration and extent of peptide folding. The present study provides an insight into formulation strategies designed to reduce the potential risk of physical and chemical degradation of peptides with a defined conformation.

In Vitro Testing of Sunscreens for Dermal Absorption: A Platform for Product Selection for Maximal Usage Clinical Trials.

Sunscreen products contain UV filters as active ingredients for the protection of the skin against UVR. The US Food and Drug Administration (FDA) issued a new proposed rule in 2019 (84.FR.6204) for sunscreens and identified the need for additional safety data for certain UV filters including their dermal absorption data. Dermal absorption data reveal systemic exposure of UV filters in humans, which can be obtained from clinical maximal usage trials. FDA guidance recommends conducting in vitro skin permeation tests (IVPTs) to help select formulations for maximal usage clinical trials as IVPT results may be indicative of in vivo absorption. This case study reports in vitro methodologies used for the selection of sunscreen products for an FDA-sponsored proof-of-concept maximal usage clinical trial. An IVPT method was developed using human cadaver skin. Commercially available sunscreen products were tested to determine the skin absorption potential of common UV filters using the IVPT. All the studied sunscreen products demonstrated a certain degree of skin absorption of UV filters using IVPT, and a formulation rank order was obtained. These sunscreen products were also characterized for several formulation properties including the globule size in emulsions, which was found to be an indicator for the rank order.

Evaluation of commercially available meth-deterrent pseudoephedrine hydrochloride products.

Pseudoephedrine (PSE) extracted from its dosage forms can be used as the starting material to prepare methamphetamine by drug abusers. Recently, some pseudoephedrine drug products marketed under the over the counter (OTC) monograph have been promoted as 'meth-deterrent'. The goal of this investigation was to evaluate the extraction and dissolution of these product against controls of non-meth-deterrent products of pseudoephedrine. Immediate release (IR) PSE OTC Product-C, Product-D and Product-E with meth-deterrent claim on their packaging were selected for this study. Accordingly, OTC IR PSE tablet Product-A and OTC extended release (ER) PSE tablet Product-B, with no meth-deterrent claims, were used as controls. The extraction studies were performed on intact tablets or capsules and on manipulated products employing water, ethanol and 0.l N HCl as solvents. The extraction studies were also performed in water at elevated temperatures by heating the water in an oven and in a microwave. The dissolution studies were performed in water and 0.1 N HCl. The amount of PSE extracted from Product-C was found similar to the amount extracted from the non-meth-deterrent control Product-A. The amount of PSE extracted from Product-D and Product-E was found lower than the amount extracted from control Product-A under the conditions studied. Product-A, Product-B, and Product-C met their respective dissolution acceptance criteria. The IR Products D and E released less than 50% drug in 12 h and did not meet either IR or ER PSE tablet USP dissolution acceptance criteria. In summary, the extraction of Product-C was found to be high (approximately 85% in 30 min) and was similar in extraction to the control Product-A. The extraction of Product-D and Product-E was found less than the extraction of control Product-A. Also, Product-D and Product-E did not exhibit complete drug release. This study showed that PSE can be extracted from Product D and Product E.

Quality attributes and evaluation of pharmaceutical glass containers for parenterals.

Pharmaceutical containers for parenterals have been predominantly manufactured using glass as a packaging material of choice, especially Type-I glass, since it has been regarded as a chemically inert and an effective container closure system (CCS). Nevertheless, there have been reports and recalls related to glass quality issues, such as breakage, flakes, and particles observed in marketed products. The novelty of this research is based on the knowledge gathered from our previously conducted risk assessments and establishing a comprehensive testing platform focused on risk factors for glass container failure modes and applicability to other types of pharmaceutical containers. The evaluation of container quality attributes was performed for three model glass vials using a mechanical and chemical durability testing platform: freeze-thaw, lyophilization, compression, scratch tests; visual inspection, pH, particle size analyses, extractable, leachable and imaging studies that were conducted under normal (4 and 25 °C), and stress condition (60 °C), respectively. The performance between the glass containers tested under certain stress conditions (failure modes) were variable and differentiated. The systematic platform testing approach shows the importance of lab-based risk evaluation in assessing common failure modes of pharmaceutical containers, since the quality attributes for injectable products are complex and can impact final product quality.

Evaluation of Abuse-Deterrent Characteristics of Tablets Prepared via Hot-Melt Extrusion.

In this study, the effect of formulation variables and process parameters on the abuse-deterrent (AD) characteristics of a matrix tablet manufactured using hot-melt extrusion (HME) was investigated. The formulation variables included polyethylene oxide (PEO) grades and its input level, while the HME process parameters varied were barrel temperature profile and die diameter. Depending on the diameter of the extrudate (2.5 mm or 5.0 mm), two different downstream processes were used to prepare the tablets: cryo-milling followed by compression for the 2.5 mm extrudate, and cutting followed by compression for the 5.0 mm extrudate. A D-optimal statistical design was used to evaluate the impact of formulation and process parameters on various responses, including tablet physical strength, particle size after manipulation, syringeability and injectability, solution viscosity, extractability in solvents, and dissolution rates. It was found that the post-HME extrusion processing method played a critical role in affecting the AD characteristics of abuse-deterrent formulations, likely through changing the tablet compactability and porosity. When the extrudates were cryo-milled-compressed, the tablets could be readily manipulated by milling, which led to high degree of extractability. Under high alcohol concentration, burst drug release was observed for the tablets compressed from cryo-milled extrudates. Additionally, heat exposure during HME process caused significant drop in PEO solution viscosity, likely due to thermal degradation.

Application of Optical Coherence Tomography Freeze-Drying Microscopy for Designing Lyophilization Process and Its Impact on Process Efficiency and Product Quality.

Optical coherence tomography freeze-drying microscopy (OCT-FDM) is a novel technique that allows the three-dimensional imaging of a drug product during the entire lyophilization process. OCT-FDM consists of a single-vial freeze dryer (SVFD) affixed with an optical coherence tomography (OCT) imaging system. Unlike the conventional techniques, such as modulated differential scanning calorimetry (mDSC) and light transmission freeze-drying microscopy, used for predicting the product collapse temperature (Tc), the OCT-FDM approach seeks to mimic the actual product and process conditions during the lyophilization process. However, there is limited understanding on the application of this emerging technique to the design of the lyophilization process. In this study, we investigated the suitability of OCT-FDM technique in designing a lyophilization process. Moreover, we compared the product quality attributes of the resulting lyophilized product manufactured using Tc, a critical process control parameter, as determined by OCT-FDM versus as estimated by mDSC. OCT-FDM analysis revealed the absence of collapse even for the low protein concentration (5 mg/ml) and low solid content formulation (1%w/v) studied. This was confirmed by lab scale lyophilization. In addition, lyophilization cycles designed using Tc values obtained from OCT-FDM were more efficient with higher sublimation rate and mass flux than the conventional cycles, since drying was conducted at higher shelf temperature. Finally, the quality attributes of the products lyophilized using Tc determined by OCT-FDM and mDSC were similar, and product shrinkage and cracks were observed in all the batches of freeze-dried products irrespective of the technique employed in predicting Tc.

Effects of excipients and curing process on the abuse deterrent properties of directly compressed tablets.

The objective of the present investigation was to understand the effects of excipients and curing process on the abuse deterrent properties (ADP) of Polyox™ based directly compressible abuse deterrent tablet formulations (ADFs). The excipients investigated were lactose (monohydrate or anhydrous), microcrystalline cellulose and hydroxypropyl methylcellulose. The ADPs studied were tablet crush resistance or hardness, particle size distribution following mechanical manipulation, drug extraction in water and alcohol, syringeability and injectability. Other non-ADPs such as surface morphology and tablet dissolution were also studied. It was found that presence of 50% or more of water soluble or swellable excipient in the ADF tablets significantly affected the tablet hardness, particle size distribution following mechanical manipulation and drug extraction while small amount (5%) of excipients had either minimal or no effect on ADPs of these tablets. Addition of high molecular weight HPMC (K 100M) affected syringeability and injectability of ADF. Curing process was found to affect ADPs (hardness, particle size distribution, drug extraction and syringeability and injectability) when compared with uncured tablet. In conclusion, addition of large amount of excipients, especially water soluble ones in Polyox™ based ADF tablets increase the risk of abuse by various routes of administration.

Intra-tumoral delivery of functional ID4 protein via PCL/maltodextrin nano-particle inhibits prostate cancer growth.

ID4, a helix loop helix transcriptional regulator has emerged as a tumor suppressor in prostate cancer. Epigenetic silencing of ID4 promotes prostate cancer whereas ectopic expression in prostate cancer cell lines blocks cancer phenotype. To directly investigate the anti-tumor property, full length human recombinant ID4 encapsulated in biodegradable Polycaprolactone/Maltodextrin (PCL-MD) nano-carrier was delivered to LNCaP cells in which the native ID4 was stably silenced (LNCaP(-)ID4). The cellular uptake of ID4 resulted in increased apoptosis, decreased proliferation and colony formation. Intratumoral delivery of PCL-MD ID4 into growing LNCaP(-)ID4 tumors in SCID mice significantly reduced the tumor volume compared to the tumors treated with chemotherapeutic Docetaxel. The study supports the feasibility of using nano-carrier encapsulated ID4 protein as a therapeutic. Mechanistically, ID4 may assimilate multiple regulatory pathways for example epigenetic re-programming, integration of multiple AR co-regulators or signaling pathways resulting in tumor suppressor activity of ID4.

Assessing impact of formulation and process variables on in-vitro performance of directly compressed abuse deterrent formulations.

Prescription drug products abuse/misuse is epidemic in United States. Opioids drug forms major portion of prescription drug product abuse. Abuse deterrence formulation (ADF) is one of the many approaches taken by sponsors to tackle this problem. It involves formulating opioids into dosage forms that will be difficult to abuse/misuse. Current investigation focused on evaluating the abuse deterrent properties (ADP) of ADF manufactured by direct compression method. Effect of process and formulation variables on ADP was investigated by statistical design of experiment (fractional factorial design). Independent factors studied were molecular weight of polyethylene oxide (Polyox™), curing time, temperature and method, and antioxidant type. Sotalol hydrochloride was selected as a model drug. ADP investigated were hardness/crush resistance, syringeability and injectability, physical manipulation (reduction into powder) and drug extraction in water and alcohol. Hardness and syringeability are evaluated by newly developed quantitative procedure. Other properties were also investigated such as morphology, crystallinity, assay and dissolution. The hardness and drug extraction was significantly (p<0.05) affected by curing temperature. Formulations could be powdered in 3 min irrespective of their hardness. Syringeability and injectability were intrinsic properties of the polymer used in the formulation, and were not affected by the investigated factors. Crystallinity of the polymer and drug changed, and was dependent upon curing temperature and time. The dissolution and assay were independent of formulation and process parameters studied. In conclusion, the study indicated some advantages of ADF product compared to non-ADF prepared by direct compression. However, the ADF should not be viewed as abuse proof product rather as incrementally improved product.

Spectroscopic-Based Chemometric Models for Quantifying Low Levels of Solid-State Transitions in Extended Release Theophylline Formulations.

Variations in the solid state form of a pharmaceutical solid have profound impact on the product quality and clinical performance. Quantitative models that allow rapid and accurate determination of polymorphic changes in pharmaceutical products are essential in ensuring product quality throughout its lifecycle. This study reports the development and validation of chemometric models of Raman and near infrared spectroscopy (NIR) for quantifying the extent of pseudopolymorphic transitions of theophylline in extended release formulations. The chemometric models were developed using sample matrices consisting of the commonly used excipients and at the ratios in commercially available products. A combination of scatter removal (multiplicative signal correction and standard normal variate) and derivatization (Savitzky-Golay second derivative) algorithm were used for data pretreatment. Partial least squares and principal component regression models were developed and their performance assessed. Diagnostic statistics such as the root mean square error, correlation coefficient, bias and Q(2) were used as parameters to test the model fit and performance. The models developed had a good fit and performance as shown by the values of the diagnostic statistics. The model diagnostic statistics were similar for MSC-SG and SNV-SG treated spectra. Similarly, PLSR and PCR models had comparable performance. Raman chemometric models were slightly better than their corresponding NIR model. The Raman and NIR chemometric models developed had good accuracy and precision as demonstrated by closeness of the predicted values for the independent observations to the actual TMO content hence the developed models can serve as useful tools in quantifying and controlling solid state transitions in extended release theophylline products.

Application of NIR chemometric methods for quantification of the crystalline fraction of warfarin sodium in drug product.

Monitoring of the physical state of warfarin sodium (WS) in products is essential for minimizing product quality variability in order to ensure consistent clinical performance. This study reports the development of chemometric models for quantifying the crystalline and amorphous fractions of WS in commercial drug products using NIR spectroscopy. Formulations based on commercially available products with different API to excipient ratio were used for the study. For each content, two formulations containing either lactose monohydrate or lactose anhydrous as the predominant formulation excipient were prepared. Two formulations containing either 100% amorphous WS (AWS) or crystalline WS (CWS) were prepared and mixed in various ratios to obtain sample matrices containing AWS/CWS 0-100%. The uniformity of the samples was confirmed by near infrared chemical imaging. Data were mathematically pretreated by multiplicative signal correction and Savitzky-Golay second derivative. Principal component regression and partial least square regression models were developed from mathematically treated data. All the models showed linear trend for amorphous and crystalline fractions of the WS as indicated by correlation and R(2) > 0.99 and >0.98, respectively. The models demonstrated good performance parameters with a low-root mean squared error, standard error and bias. The model predicted CWS and AWS contents were in very close agreement with the actual values. The study indicated the utility of NIR chemometric methods in quantification of the crystalline and/or amorphous fraction of WS in its products.

Impact of formulation and process variables on solid-state stability of theophylline in controlled release formulations.

Understanding the impact of pharmaceutical processing, formulation excipients and their interactions on the solid-state transitions of pharmaceutical solids during use and in storage is critical in ensuring consistent product performance. This study reports the effect of polymer viscosity, diluent type, granulation and granulating fluid (water and isopropanol) on the pseudopolymorphic transition of theophylline anhydrous (THA) in controlled release formulations as well as the implications of this transition on critical quality attributes of the tablets. Accordingly, 12 formulations were prepared using a full factorial screening design and monitored over a 3 month period at 40 °C and 75%. Physicochemical characterization revealed a drastic drop in tablet hardness accompanied by a very significant increase in moisture content and swelling of all formulations. Spectroscopic analysis (ssNMR, Raman, NIR and PXRD) indicated conversion of THA to theophylline monohydrate (TMO) in all formulations prepared by aqueous wet granulation in as early as two weeks. Although all freshly prepared formulations contained THA, the hydration-dehydration process induced during aqueous wet granulation hastened the pseudopolymorphic conversion of theophylline during storage through a cascade of events. On the other hand, no solid state transformation was observed in directly compressed formulations and formulations in which isopropanol was employed as a granulating fluid even after the twelve weeks study period. The transition of THA to TMO resulted in a decrease in dissolution while an increase in dissolution was observed in directly compressed and IPA granulated formulation. Consequently, the impact of pseudopolymorphic transition of theophylline on dissolution in controlled release formulations may be the net result of two opposing factors: swelling and softening of the tablets which tend to favor an increase in drug dissolution and hydration of theophylline which decreases the drug dissolution.

Evaluation of In-Use Stability of Anticoagulant Drug Products: Warfarin Sodium.

The objective of the study was to evaluate the stability of warfarin products during use by patients or caregivers. For evaluation, three commercial products manufactured by different processes were selected and placed at 30°C/75%RH to simulate in use condition. Samples were withdrawn up to 12 weeks and analyzed for the physicochemical changes. Scanning electron microscopy demonstrated increasing holes and craters in the tablets over the timeframe. Near-infrared chemical imaging and powder X-ray powder diffraction corroborated the change arising from conversion of crystalline to amorphous forms of the drug. Hardness and disintegration time of the tablets were found to increase progressively. With increasing time, moisture contents of the products were found to increase and consequent decrease in isopropyl alcohol content of the product. Dissolution of the tablets in media at pH 4.5 demonstrated discrimination between crystalline and amorphous drug products. Overall, percent drug dissolved in each product at 30 min was found to decrease with increasing exposure time. Dissolution of drug decreased from 54% to 38% and 82% to 54% for the two products while the third product maintained consistently high level of dissolution. These results suggest that the drug product quality attributes can change during use.

Understanding effect of formulation and manufacturing variables on the critical quality attributes of warfarin sodium product.

Warfarin sodium (WS) is a narrow therapeutic index drug and its product quality should be thoroughly understood and monitored in order to avoid clinical performance issues. This study was focused on understanding the effect of manufacturing and formulation variables on WS product critical quality attributes (CQAs). Eight formulations were developed with lactose monohydrate (LM) or lactose anhydrous (LA), and were either wet granulated or directly compressed. Formulations were granulated either with ethanol, isopropyl alcohol (IPA) and IPA-water mixture (50:50). Formulations were characterized for IPA, water content, hardness, disintegration time (DT), assay, dissolution and drug physical forms (scanning electron microscopy (SEM), near infrared chemical imaging (NIR-CI), X-ray powder diffraction (XRPD) and solid state nuclear magnetic resonance (ssNMR)), and performed accelerated stability studies at 40°C/75% RH for three days. The DT and dissolution of directly compressed formulations were faster than wet granulated formulations. This was due to phase transformation of crystalline drug into its amorphous form as indicated by SEM, NIR-CI, XRPD and ssNMR data which itself act as a binder. Similarly, LM showed faster disintegration and dissolution than LA containing formulations. Stability results indicated an increase in hardness and DT, and a decrease in dissolution rate and extent. This was due to phase transformation of the drug and consolidation with particles' bonding. In conclusion, the CQAs of WS product were significantly affected by manufacturing and formulation variables.

Polycaprolactone/maltodextrin nanocarrier for intracellular drug delivery: formulation, uptake mechanism, internalization kinetics, and subcellular localization.

Prostate cancer (PCa) disease progression is associated with significant changes in intracellular and extracellular proteins, intracellular signaling mechanism, and cancer cell phenotype. These changes may have direct impact on the cellular interactions with nanocarriers; hence, there is the need for a much-detailed understanding, as nanocarrier cellular internalization and intracellular sorting mechanism correlate directly with bioavailability and clinical efficacy. In this study, we report the differences in the rate and mechanism of cellular internalization of a biocompatible polycaprolactone (PCL)/maltodextrin (MD) nanocarrier system for intracellular drug delivery in LNCaP, PC3, and DU145 PCa cell lines. PCL/MD nanocarriers were designed and characterized. PCL/MD nanocarriers significantly increased the intracellular concentration of coumarin-6 and fluorescein isothiocyanate-labeled bovine serum albumin, a model hydrophobic and large molecule, respectively. Fluorescence microscopy and flow cytometry analysis revealed rapid internalization of the nanocarrier. The extent of nanocarrier cellular internalization correlated directly with cell line aggressiveness. PCL/MD internalization was highest in PC3 followed by DU145 and LNCaP, respectively. Uptake in all PCa cell lines was metabolically dependent. Extraction of endogenous cholesterol by methyl-ß-cyclodextrin reduced uptake by 75%±4.53% in PC3, 64%±6.01% in LNCaP, and 50%±4.50% in DU145, indicating the involvement of endogenous cholesterol in cellular internalization. Internalization of the nanocarrier in LNCaP was mediated mainly by macropinocytosis and clathrin-independent pathways, while internalization in PC3 and DU145 involved clathrin-mediated endocytosis, clathrin-independent pathways, and macropinocytosis. Fluorescence microscopy showed a very diffused and non-compartmentalized subcellular localization of the PCL/MD nanocarriers with possible intranuclear localization and minor colocalization in the lysosomes with time.

Development and validation of X-ray diffraction method for quantitative determination of crystallinity in warfarin sodium products.

The objective of this study was to develop and validate XRPD analytical method for the estimation of percent crystalline warfarin sodium present in drug products. Warfarin sodium (WS) is a clathrate containing Isopropyl alcohol entrapped in the crystalline structure. Four types of WS-excipient mixtures were prepared and used to make four formulations: M1 containing lactose monohydrate (WS: excipient 1:9), M2 containing anhydrous lactose (WS: excipient 1:9), M3 containing lactose monohydrate (WS: excipient 1:21.5), M4 containing lactose anhydrous (WS: excipient 1:21.5). Thoroughly mixed powders were packed in the XRD sample holders and diffractogram were collected. Diffractogram in the 7-9 2θ were found to be distinctive as the peak intensity grows with increasing percent crystalline WS. This peak region was, therefore, used to validate the XRPD method. Validation parameters were evaluated for accuracy, precision, linearity, limit of detection (LOD), and limit of quantitation (LOQ). LOD and LOQ for M1, M2, M3, and M4 were 3.04, 3.17, 4.17, 4.49% and 9.21, 9.62, 12.65, 13.30%, respectively. The method was found to be linear with R(2)>0.99. With changing scan speed, X-ray power output, and type of sample holder, the method was found to be robust. Prediction of the % crystalline content of the WS sample with known crystallinity showed close agreement between actual and predicted value. In summary, XRPD method was validated, which can be used as a quantitative method for the estimation of % crystalline WS present in a drug product.

Chemometric Model Development and Comparison of Raman and (13)C Solid-State Nuclear Magnetic Resonance-Chemometric Methods for Quantification of Crystalline/Amorphous Warfarin Sodium Fraction in the Formulations.

Warfarin sodium (WS) exists in multiple solid-state forms. The solid-state forms differ in physicochemical properties, and crystalline changes in the drug formulation may influence on the drug product quality and/or clinical performance. It is, therefore, critically important to have a good and reliable analytical method to monitor and quantitate this transformation during stability studies. The aim of the present research was to investigate Raman spectroscopy and solid-state nuclear magnetic resonance ((13)C ssNMR) methods in conjunction with chemometry to quantitate the amorphous and crystalline WS fractions in the drug products. Compositionally identical formulations of amorphous and crystalline WS were prepared, and mixed in various proportions to make 0%-100% amorphous/crystalline sample matrices. Raman and (13)C ssNMR spectra were collected and subjected to partial-least-squares and principle component regressions after mathematical treatment of the data. The model performance parameters such as root-mean-square error of prediction, standard error of prediction, and bias were low for Raman models in comparison to (13)C ssNMR models. Models predicted values of the independent sample matrices match closely with the actual values at high level of crystalline WS. Thus, the developed methods provide means to control and quantitate the WS forms fraction in the drug product.

Stability characterization and appearance of particulates in a lyophilized formulation of a model peptide hormone-human secretin.

Drug shortages and recalls are often caused due to particulate growth in parenteral products and can have serious clinical implications. Root cause analysis of such recalls and shortages may arise due to insufficient understanding of process, formulations issues and environmental effects than often reported filtration and inadequate personnel training. Therefore, the goal of this study was to use a model peptide hormone, secretin that is currently under drug shortage, and investigate the effect of excipients on the lyophilized secretin formulation and evaluate the effect of storage and excursion temperatures. Lyophilized formulation was assayed for secretin by reverse phase HPLC. Solid state characteristics of lyophilized formulation were determined by X-ray powder diffraction (XRPD), thermal and spectroscopic methods. Dynamic light scattering (DLS) was used to detect particulates in the formulation after reconstitution. To assess the environmental impact, the lyophilized samples were stored at -20°C, 4°C, 25°C and 25°C/60%RH and analyzed at time 0, 1, 4, and 8 weeks. HPLC analyses exhibited a decrease in secretin concentration by 8 week (20-27% fold decrease). Visual observation and DLS showed particulates and increased reconstitution time (e.g., at 25°C/60%RH, particle size of ∼390 nm at day 0 to >2 µm as early as week 1; reconstitution time of ∼20s at day 0 to ∼67s at week 8). XRPD, thermal and spectroscopic methods demonstrated polymorphic transitions of mannitol and increased crystallinity in the lyophilized formulations with time. These studies potentially address the effect of product excursions outside the proposed label storage conditions which is -20°C for secretin formulation and this is the first time it has been investigated. These observations indicate that both environmental factor and excipient may have an impact on the stability of secretin formulation and appearance of particles in the product.

Inhibitor of differentiation 4 (ID4) inactivation promotes de novo steroidogenesis and castration-resistant prostate cancer.

Prostate cancer (PCa) is the most commonly diagnosed cancer in men in the Western world. The transition of androgen-dependent PCa to castration-resistant (CRPC) is a major clinical manifestation during disease progression and presents a therapeutic challenge. Our studies have shown that genetic ablation of inhibitor of differentiation 4 (Id4), a dominant-negative helix loop helix protein, in mice results in prostatic intraepithelial neoplasia lesions and decreased Nkx3.1 expression without the loss of androgen receptor (Ar) expression. ID4 is also epigenetically silenced in the majority of PCa. However, the clinical relevance and molecular pathways altered by ID4 inactivation in PCa are not known. This study investigates the effect of loss of ID4 in PCa cell lines on tumorigenicity and addresses the underlying mechanism. Stable silencing of ID4 in LNCaP cells (L-ID4) resulted in increased proliferation, migration, invasion, and anchorage-independent growth. An increase in the rate of tumor growth, weight, and volume was observed in L-ID4 xenografts compared with that in the LNCaP cells transfected with nonspecific short hairpin RNA (L+ns) in noncastrated mice. Interestingly, tumors were also observed in castrated mice, suggesting that loss of ID4 promotes CRPC. RNA sequence analysis revealed a gene signature mimicking that of constitutively active AR in L-ID4, which was consistent with gain of de novo steroidogenesis. Prostate-specific antigen expression as a result of persistent AR activation was observed in L-ID4 cells but not in L+ns cells. The results demonstrate that ID4 acts as a tumor suppressor in PCa, and its loss, frequently observed in PCa, promotes CRPC through constitutive AR activation.