Nanomaterials have expanded the use of active pharmaceutical ingredients by improving efficacy, decreasing toxicity, and facilitating targeted delivery. To systematically achieve this goal, ...nanomaterial-containing drugs need to be manufactured with precision in attributes such as size, morphology, surface chemistry, and composition. Their physicochemical characterization is essential as their attributes govern pharmacokinetics yet can be challenging due to the nature of many nanomaterial-based formulations unless advanced sample fixation and in vitro characterization methods are utilized. Here, different cryogenic and other fixation strategies were assessed, and a novel physicochemical characterization method was developed using scanning electron Raman cryo-microscopy (SERCM). A complex nanoparticle albumin bound paclitaxel (nab-paclitaxel) formulation was chosen as a model drug. Plunge freezing (PF), high pressure freezing (HPF), freeze substitution (FS), and membrane filtration were compared for their influence on size and morphology measurements, and formulation-based variations were quantified. SERCM was introduced as a multiattribute physicochemical characterization platform, and the composition of nanoparticles was confirmed as albumin-paclitaxel complexes. By coupling image-based quantitative analysis with chemical analysis, SERCM has the potential to pave the way for the development of comprehensive tools for assessing injectable and ophthalmic nanomaterial-containing drugs in their native-like state.
Pregnenolone (PREG) is an endogenous steroid frequently sold as an over-the-counter dietary supplement touted to promote neurological and immunological health. While the PREG dietary supplement is ...added to the diet for health benefits, there are no FDA approved PREG drugs. However, compounded PREG drug products are available to U.S. patients. The FDA works with state regulatory authorities on the oversight of compounding activities, including developing 503A and 503B lists of bulk substances that compounders are permitted to use. PREG is one of the substances publicly nominated to be included on the 503B list. Compounded hormone therapies such as those using PREG are of interest given the lack of standardization in compounded drug products which may increase the possibility of underdosing, overdosing, or contamination. However, no USP monograph currently exists to evaluate the quality of PREG drug substance or product. To address knowledge gaps and assist in quality control, a simple and rapid quantitative proton nuclear magnetic resonance spectroscopy (qNMR) method for the identification and assay of PREG in different types of PREG products was developed and validated. PREG samples were characterized using 1D 1H and 2D 1H–13C HSQC NMR spectra. The qNMR assay method (taking approximately 10 min per NMR spectrum) was validated for precision, accuracy, specificity, robustness and linearity per ICH Q2(R1) guidance. The method was validated in a range from 0.032 to 3.2 mg/mL. As a proof of concept, seven PREG bulk substance samples, three tablet and two capsule PREG dietary supplements were assessed by the qNMR analytical procedure. NMR data from all tested samples met the expected criteria for identification and assay. The results demonstrate the potential of qNMR for the quality assessment of different types of PREG samples.
•Quantitative 1H NMR (qNMR) method was developed and validated to identify and assay pregnenolone.•Validation followed International Council for Harmonization Q2(R1) guidelines.•Precision and accuracy of the qNMR method were demonstrated at the analytical concentration 2.0 mg/mL.•The method was successfully applied to assay pregnenolone bulk substance and dietary supplement samples.
Abstract The homelessness and child protective services (CPS) systems are closely linked. This study examines the patterns and sequence of families’ involvement with homeless shelters and CPS, as ...well as whether involvement in each system predicts involvement in the other using linked administrative records for 258 families recruited in emergency shelters in Alameda County, California. More than half of families were reported to CPS at some point, but less than one-fifth ever had a report substantiated. Reports that were uninvestigated or unfounded increased in the months leading up to shelter entry and spiked immediately afterward, but substantiations and child removals increased only later. Shelter use before study entry was associated with CPS referrals and investigations after study entry, although not with substantiated cases or child removals. However, CPS involvement before study entry was not associated with returns to shelter after study entry. These results imply that an unsubstantiated report of neglect or abuse may serve as an early warning signal for homelessness and that preventive strategies aiming to affect both homeless and child protective systems should focus on reducing homelessness. CPS workers should evaluate families’ housing needs and attempt to link families to appropriate resources. Black families were disproportionately referred to CPS after shelter entry after controlling for other family characteristics, but race was not associated with substantiations of neglect or abuse or with child removals. Findings lend modest support to human decision-making and institutional explanations of racial disproportionalities in CPS involvement, especially for reporters outside of the CPS system.
Potential infiltration of counterfeit drug productscontaining the wrong or no active pharmaceutical ingredient (API)into the bona fide drug supply poses a significant threat to consumers worldwide. ...Raman spectroscopy offers a rapid, nondestructive avenue to screen a high throughput of samples. Traditional qualitative Raman identification is typically done with spectral correlation methods that compare the spectrum of a reference sample to an unknown. This is often effective for pure materials but is quite challenging when dealing with drug products that contain different formulations of active and inactive ingredients. Typically, reliable identification of drug products using common spectral correlation algorithms can only be made if the specific product under study is present in the library of reference spectra, thereby limiting the scope of products that can be screened. In this paper, we introduce the concept of the Raman barcode for identification of drug products by comparing the known peaks in the API reference spectrum to the peaks present in the finished drug product under study. This method requires the transformation of the Raman spectra of both API and finished drug products into a barcode representation by assigning zero intensity to every spectral frequency except the frequencies that correspond to Raman peaks. By comparing the percentage of nonzero overlap between the expected API barcode and finished drug product barcode, the identity of API present can be confirmed. In this study, 18 approved finished drug products and nine simulated counterfeits were successfully identified with 100% accuracy utilizing this method.
A private testing laboratory reported in a Citizen Petition (CP) to FDA that 16 of 38 metformin drug products they tested had
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-nitrosodimethyl amine (NDMA) amounts above the allowable intake (AI) ...of 96 ng/day. Because the FDA had been monitoring drugs for nitrosamines, orthogonal analytical procedures had been developed, validated and applied to detect the following nitrosamines in metformin drug products (if present): (i) NDMA (with a dedicated method) or (ii) NDMA (with a second confirmatory method),
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-nitroso-diethylamine (NDEA),
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-ethyl-
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-nitroso-2-propanamine (NEIPA),
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-nitroso-diisopropylamine (NDIPA),
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-nitroso-di-n-propylamine (NDPA),
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-nitroso-methylphenylamine (NMPA),
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-nitroso-di-n-butylamine (NDBA) and
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-nitroso-
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-methyl-4-aminobutyric acid (NMBA). In contrast to the private laboratory results, FDA testing on the same set of 38 samples with orthogonal procedures observed amounts over the AI in only 8 of the 38 products and generally observed lower values than reported by the private testing laboratory. As described here, the investigation into the cause of the discrepancy revealed that
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-dimethylformamide (DMF) can interfere with NDMA measurements. The data showed that the use of sufficient mass accuracy in the data acquisition and appropriate mass tolerance setting in the data processing to assure the selectivity of mass spectrometry measurements of NDMA in the presence of co-eluting DMF was necessary to prevent overestimation of the level of NDMA in metformin drug products. Overall, care should be taken to assure the necessary specificity in analytical procedures for adequate assessment of the nitrosamine level in drug products that also contain DMF or other potential interfering substances.
In this study, an alternative method to compendial analytical procedures with enhanced detection and separation capabilities was validated for the quality assessment of glutathione (GSH) drug ...substance. The related impurities A, B, C, and D present in GSH drug substance were characterized using a one-dimension proton nuclear magnetic resonance (1D 1H NMR) method on a 600 MHz spectrometer equipped with a liquid nitrogen cryoprobe. Two sample preparations at different pH were optimized to ensure the unambiguous identification of different impurities in the GSH samples. Specifically, impurities A and C in a GSH sample can be tested at pH 3.0, while pH 7.4 is more suitable for testing impurities B and D. The quantitative NMR (qNMR) method was validated following International Council for Harmonisation (ICH) guidelines. The limit of detection (LOD) was less than 0.1% wt for an individual impurity, and the limit of quantitation (LOQ) ranged from 0.14 to 0.24% wt, using about 14 min experimental time per spectrum. Following validation, the qNMR method was applied to assess different commercial GSH bulk substance samples, an in-house compounded GSH drug product, and a GSH dietary supplement product. The method was also applied to monitor GSH degradation (hydrolysis and oxidation) over time to provide quantitative information on GSH degradation and stability. The results suggest that the qNMR method can serve as a highly specific and efficient orthogonal tool for assessing the quality of GSH pharmaceuticals, providing both qualitative and quantitative information on GSH and its related impurities A-D.
•Highly specific quantitative 1H NMR (qNMR) method was developed and validated to qualify and quantitate glutathione and its related impurities A, B, C, and D.•The qNMR method was successfully applied to assess the quality of different glutathione bulk substance, compounded drug and dietary supplement samples.
In vitro
dissolution testing is widely used to mimic and predict
in vivo
performance of oral drug products in the gastrointestinal (GI) tract. This literature review assesses the current
in vitro
...dissolution methodologies being employed to simulate and predict
in vivo
drug dissolution under fasted and fed conditions, with emphasis on immediate release (IR) solid oral dosage forms. Notable human GI physiological conditions under fasted and fed states have been reviewed and summarized. Literature results showed that dissolution media, mechanical forces, and transit times are key dissolution test parameters for simulating specific postprandial conditions. A number of biorelevant systems, including the fed stomach model (FSM), GastroDuo device, dynamic gastric model (DGM), simulated gastrointestinal tract models (TIM), and the human gastric simulator (HGS), have been developed to mimic the postprandial state of the stomach. While these models have assisted in expanding physiological relevance of
in vitro
dissolution tests, in general, these models lack the ability to fully replicate physiological conditions/processes. Furthermore, the translatability of
in vitro
data to an
in vivo
system remains challenging. Additionally, physiologically based pharmacokinetic (PBPK) modeling has been employed to evaluate the effect of food on drug bioavailability and bioequivalence. Here, we assess the current status of
in vitro
dissolution methodologies and absorption PBPK modeling approaches to identify knowledge gaps and facilitate further development of
in vitro
dissolution methods that factor in fasted and fed states. Prediction of
in vivo
drug performance under fasted and fed conditions
via in vitro
dissolution testing and modeling may potentially help efforts in harmonizing global regulatory recommendations regarding
in vivo
fasted and fed bioequivalence studies for solid oral IR products.
Graphical abstract
Tandem mass spectrometry (MS/MS) can provide direct and accurate sequence characterization of synthetic oligonucleotide drugs, including modified oligonucleotides. Multiple factors can affect ...oligonucleotide MS/MS sequencing, including the intrinsic properties of oligonucleotides (i.e., nucleotide composition and structural modifications) and instrument parameters associated with the ion activation for fragmentation. In this study, MS/MS sequencing of a thymidine (T)‐rich and phosphorothioate (PS)‐modified DNA oligonucleotide was investigated using two fragmentation techniques: trap‐type collision‐induced dissociation (“CID”) and beam‐type CID also termed as higher‐energy collisional dissociation (“HCD”), preceded by a hydrophilic interaction liquid chromatography (HILIC) separation. A low to moderate charge state (−4), which predominated under the optimized HILIC‐MS conditions, was selected as the precursor ion for MS/MS analysis. Comparison of the two distinctive ion activation mechanisms on the same precursor demonstrated that HCD was superior to CID in promoting higher sequence coverage and analytical sensitivity in sequence elucidation of T‐rich DNA oligonucleotides. Specifically, HCD provided more sequence‐defining fragments with higher fragment intensities than CID. Furthermore, the direct comparison between unmodified and PS‐modified DNA oligonucleotides demonstrated a loss of MS/MS fragmentation efficiency by PS modification in both CID and HCD approaches, and a resultant reduction in sequence coverage. The deficiency in PS DNA sequence coverage observed with single collision energy HCD, however, was partially recovered by applying HCD with multiple collision energies. Collectively, this work demonstrated that HCD is advantageous to MS/MS sequencing of T‐rich PS‐modified DNA oligonucleotides.
Analyzing coeluting impurities with similar masses in synthetic oligonucleotides by liquid chromatography–mass spectrometry (LC-MS) poses challenges due to inadequate separation in either dimension. ...Herein, we present a direct method employing fully resolved isotopic envelopes, enabled by high resolution mass spectrometry (HRMS), to identify and quantify isobaric impurity ions resulting from the deletion or addition of a uracil (U) or cytosine (C) nucleotide from or to the full-length sequence. These impurities may each encompass multiple sequence variants arising from various deletion or addition sites. The method utilizes a full or targeted MS analysis to measure accurate isotopic distributions that are chemical formula dependent but nucleotide sequence independent. This characteristic enables the quantification of isobaric impurity ions involving sequence variants, a capability typically unavailable in sequence-dependent MS/MS methods. Notably, this approach does not rely on standard curves to determine isobaric impurity compositions in test samples; instead, it utilizes the individual isotopic distributions measured for each impurity standard. Moreover, in cases where specific impurity standards are unavailable, the measured isotopic distributions can be adequately replaced with the theoretical distributions (calculated based on chemical formulas of standards) adjusted using experiment-specific correction factors. In summary, this streamlined approach overcomes the limitations of LC-MS analysis for coeluting isobaric impurity ions, offering a promising solution for the in-depth profiling of complex impurity mixtures in synthetic oligonucleotide therapeutics.
Two decades ago, postmarket discovery of a second crystal form of ritonavir with lower solubility had major implications for drug manufacturers and patients. Since then, ritonavir has been ...reformulated via the hot–melt–extrusion process in an amorphous form. Here, quantitative low- and mid-frequency Raman spectroscopy methods were developed to characterize polymorphs, form I and form II, in commercial ritonavir 100 mg oral tablets as an alternate analysis approach compared to X-ray powder diffraction (XRPD). Crystallization in three lots of ritonavir products obtained from four separate manufacturers was assessed after storage under accelerated conditions at 40 °C and 75% relative humidity (RH). Results were compared with quantitative XRPD methods developed and validated according to ICH Q2 (R1) guidelines. In a four-week open-dish study, form I crystallization occurred in two of the four products and form II crystallization was detected in another ritonavir product. The limits of detection for XRPD, low-frequency Raman (LFR), and mid-frequency Raman (MFR) were determined to be 0.7, 0.8, and 0.5% for form I and 0.6, 0.6, and 1% for form II, respectively. Root-mean-squared-error of predictions were 0.6–1.0 and 0.6–2.5% for LFR- and MFR-based partial least-squares models. Further, ritonavir polymorphs could also be identified and detected directly from ritonavir tablets using transmission LFR. In summary, LFR was applied for the assessment of polymorphism in real-world samples. While providing analytical performance similar to conventional techniques, LFR reduced the single measurement time from 66 min (XRPD) to 10 s (LFR) without the need for tedious sample preparation procedures.
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