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Professor Walkiria Schlindwein

Job: Professor of Pharmaceutics

Faculty: Health and Life Sciences

School/department: Leicester School of Pharmacy

Research group(s): Pharmaceutical Technologies

Address: 制服无码, The Gateway, Leicester, LE1 9BH.

T: +44 (0)116 257 7124

E: wss@dmu.ac.uk

W: /pharmacy

 

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Personal profile

Prof Schlindwein graduated as Chemical Engineer in 1984 from the Federal University of Rio de Janeiro, UFRJ, Brazil. She obtained her M.Sc. in Polymer Science and Technology from the Institute of Macromolecules of the UFRJ, Brazil in 1986, PhD in Chemistry from the Department of Chemistry of the University of Leicester, England, in 1990, and DSc in Chemistry from the UFRJ in 1992. 

She has over 25 years of experience in academia and is currently Professor of Pharmaceutics at the Leicester School of Pharmacy, 制服无码 (DMU). She has led the creation of the first MSc in Pharmaceutical Quality by Design (QbD) that has attracted national and international students since 2012. In the UK, education provision in the QbD area has been largely dominated by this programme. She has established a high-profile curriculum in this domain, through engagement with a number of multinational companies, including Astra Zeneca and GlaxoSmithKline, technology providers and the UK regulatory agency, MHRA. She has chaired several events and workshops to support and publicise the research and teaching excellence in pharmaceutical product development and manufacture. Her expertise is in the areas of polymer science and technology, advanced techniques for materials’ characterisation, pharmaceutical Quality by Design, and extrusion processes for early phase product development using in-line analytical tools

Research group affiliations

  • Leicester Institute for Pharmaceutical Health and Social Care Innovations

Publications and outputs


  • dc.title: Predicting the compressibility and compactibility profiles of pharmaceutical active ingredients for design of multi-component tablets dc.contributor.author: Cheng, Chuhong; Wang, Ke; Schlindwein, W. S.; Crean, Carol; Wu, Chuan-Yu; He, Zhonggui; Liu, Xiaohong; Li, Mingzhong dc.description.abstract: Digital design of multi-component pharmaceutical tablets based on the properties of individual constituents plays a critical role in the rational design and optimisation of pharmaceutical formulations. Most active pharmaceutical ingredients (APIs) used in tablet formulations are crystalline materials with diverse mechanical properties, including elastic, plastic, brittle, or combined deformation characteristics. These properties can lead to manufacturing challenges such as capping and sticking during the tableting process, or the formation of fragile tablets, making the direct compaction and testing of pure API tablets difficult or even impossible. In this study, we present an approach to predict the compressibility and compactibility profiles of APIs that cannot be directly compacted into tablets without the support of excipients. The method is based on the assumptions of additive volume fractions and the geometric mean mixing rule applied to the compactibility models of the individual components. API compressibility and compactibility models were derived from the analysis of 鈥渙ut-of-die鈥� compaction data obtained from binary powder mixtures containing 50% API and 50% microcrystalline cellulose, compressed at different compaction pressures. Five APIs with diverse mechanical properties, i.e., aspirin, carbamazepine, metronidazole, paracetamol, and theophylline, were investigated. The proposed approach successfully predicted tablet solid fractions and tensile strengths for both binary (API and filler) and ternary (API, filler and disintegrant) mixtures of the APIs. The predicted tablet solid fractions were within 卤 5% of the measured values, while tensile strength predictions showed errors typically ranging from 卤 20% to 卤 50%, depending on the API, formulation, and compaction pressure. Overall, the approach provides a practical digital design tool for the formulation of multi-component pharmaceutical tablets based on constituent material properties. dc.description: open access article

  • dc.title: Hot-melt extruded ibuprofen ternary solid dispersions using in-line UV鈥揤is: Impact of an ionizable polymer on thermodynamics and dissolution dc.contributor.author: de Castro, Matheus; Almeida, Melissa; Luebbert, Christian; Madu, Shadrack Joel; Khurana, Jatin; Evans, Mark; Leivers, Matthew; Araujo, Gabriel; Li, Mingzhong; Schlindwein, W. S. dc.description.abstract: Amorphous solid dispersions (ASDs) remain a key strategy for enhancing the dissolution of poorly soluble APIs. Building on previous work with binary ibuprofen (IBU) blends, this study investigates the impact of incorporating poly(butyl methacrylate-co-(2-dimethylaminoethyl) methacrylate-co-methyl methacrylate), Eudragit EPO庐 (EPO), an ionizable third polymer into systems based on poly(vinylpyrrolidone-co-vinyl acetate), typically 60:40 VP:VA ratio, KOLVA64庐 (VA64), Polyvinylpyrrolidone, KOL17PF庐 (17PF) and hydroxypropyl methylcellulose acetate succinate, AQOAT AS-LMP (HPMCAS). Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) modeling was employed to predict solid鈥搇iquid (SLE) and liquid-liquid (LLE) phase equilibria using binary interaction parameters (kij). In comparison to Flory鈥揌uggins's theory, PC-SAFT predicted broader metastable regions, corresponding to up to threefold higher achievable ibuprofen loadings. ASDs (35 wt%) with increasing EPO concentration (0鈥�32.5 wt%) were successfully extruded using in-line UV鈥揤is spectroscopy for real-time monitoring, with samples grouped according to polymeric composition by principal component analysis (PCA). Solid-state analyses (FTIR, XRD, DSC) of extrudate samples confirmed no recrystallisation for up to six months (25 掳C/70% RH). Small-scale DSC experiments within the PC-SAFT-predicted unstable zone confirmed crystallinity (95 wt% for VA64-EPO and 17PF-EPO; 50 wt% for HPMCAS-EPO). Dissolution studies under acidic conditions revealed complete release of blends with 鈮�20 wt% EPO within 5 min, outperforming binary formulations and maintaining supersaturation for hours. At pH 6.8, no significant dissolution improvement was seen, providing additional evidence of a diffusion-controlled release dependent on pH and API-polymer interactions. Overall, this work presents a novel PC-SAFT-based, predict-first approach to ternary ASD design, enabling higher drug loadings and controlled pH-responsive release. dc.description: open access article

  • dc.title: Empowering digital innovation in CMC: A framework for regulatory readiness and confidence dc.contributor.author: Houson, Ian; Schlindwein, W. S.; Mustoe, Chantal L.; Markl, Daniel dc.description.abstract: Digital transformation in chemistry, manufacturing and controls (CMC) is advancing rapidly through technologies such as artificial intelligence (AI), machine learning, modelling and simulation. However, regulatory frameworks and expertise struggle to evolve at the same pace. The absence of harmonised terminology, evaluation methods and credibility standards creates uncertainty for industry and regulators, limiting the use of digital tools in regulated environments. Early regulatory engagement, consistent approaches to data provenance, and clear criteria for assessing model risk and reliability are needed to ensure confidence in digital methods. The Digital CMC Centre of Excellence in Regulatory Science and Innovation (CERSI) is addressing these gaps through the development of a practical framework, case studies and supporting tools to guide regulatory use of predictive models. This article aims to raise awareness of how realising the benefits of digital transformation in CMC depends on early alignment between innovators and regulators, underpinned by shared language and credible, risk-proportionate frameworks for evaluating predictive models across their lifecycle. It describes how the Digital CMC CERSI, through a harmonised framework, case studies, a sandbox and training, is establishing a practical, science-based approach to increase confidence and accelerate the safe regulatory adoption of digital tools. dc.description: This paper is one of the outputs of the UK Digital CMC CERSI project funded by the MHRA/UKRI/MRC in 2025-26. The project is led by the University of Strathclyde, CMAC in collaboration with DMU and CCDC

  • dc.title: Advancing amorphous solid dispersions through empirical and hybrid modeling of drug鈥損olymer solubility and miscibility: A case study using Ibuprofen dc.contributor.author: de Castro, Matheus; Cordeiro, Ana Sara; Li, Mingzhong; Lubbert, Christian; McColl, Catherine; Khurana, Jatin; Evans, Mark; Schlindwein, W. S. dc.description.abstract: This study investigates the solubility and miscibility of ibuprofen (IBU) with four pharmaceutical polymers, KOLVA64庐, KOL17PF庐, HPMCAS, and Eudragit庐 EPO, using a combination of empirical and hybrid modeling approaches, supported by differential scanning calorimetry (DSC) experiments. Traditional group contribution methods based on Hildebrand and Hansen solubility parameters (Fedors, Hoftyzer鈥搗an Krevelen, and Just鈥揃reitkreutz) showed variability in solubility predictions but consistently classified all polymer鈥揂PI blends as miscible (螖未 < 7 MPa陆). Bagley plots reinforced these findings, although borderline miscibility was indicated for HPMCAS and EPO depending on the method used. A novel attempt to derive the Flory鈥揌uggins (FH) interaction parameter (蠂) from solubility parameters at near-melting temperatures showed poor agreement with experimental data, underscoring the limitations of such extrapolations and the semi-empirical nature of the FH model. Phase diagrams were constructed from DSC-based melting point depression data using three modeling strategies: FH theory, the empirical approach by Kyeremateng (with two fitting methods), and the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state, both in pure predictions and with fitted binary interaction parameters (kij). The glass transition temperature (Tg) of the mixtures was modeled using the Gordon鈥揟aylor and Kwei equations. All models provided a consistent polymer ranking based on their solubilizing capacity, with KOL17PF as the most compatible and HPMCAS as the least. Demixing zones (liquid-liquid equilibrium - LLE) predicted by FH and PC-SAFT models suggest that for HPMCAS-based ASDs only very low drug loadings (< 5 % w/w) could potentially be stable at room temperature. In contrast, higher drug loadings (> 10 % w/w) fall under a meta-stable zone with the other polymers, making them better candidates for IBU formulation. HPMCAS also exhibited consistently prediction errors across all Tg models, (AARD 鈭�4.5 %), indicating poorer agreement with experimental data. By integrating empirical and hybrid modeling approaches, this study highlights the strengths and limitations of commonly used solubility prediction methods and advocates for a shift toward a harmonized framework. dc.description: open access article

  • dc.title: Quality by digital design to accelerate sustainable medicines development dc.contributor.author: Mustoe, Chantal L.; Turner, Alice J.; Urwin, Stephanie J.; Houson, Ian; Feilden, Helen; Markl, Daniel; Al Qaraghuli, Mohammed M.; Chong, Magdalene W.S.; Robertson, Murray; Nordon, Alison; Johnston, Blair F.; Brown, Cameron J.; Robertson, John; Adjiman, Claire; Batchelor, Hannah; Benyahia, Brahim; Bresciani, Massimo; Burcham, Christopher L.; Cardona, Javier; Cottini, Ciro; Dunn, Andrew S.; Fradet, David; Halbert, Gavin W.; Henson, Mark; Hidber, Pirmin; Langston, Marianne; Lee, Ye Seol; Li, Wei; Mantanus, J茅r么me; McGinty, John; Mehta, Bhavik; Naz, Tabbasum; Ottoboni, Sara; Prasad, Elke; Quist, Per-Ola; Reynolds, Gavin K.; Rielly, Chris; Rowland, Martin; Schlindwein, W. S.; Schroeder, Sven L.M.; Sefcik, Jan; Settanni, Ettore; Siddique, Humera; Smith, Kenneth; Smith, Rachel; Srai, Jagjit Singh; Thorat, Alpana A.; Vassileiou, Antony; Florence, Alastair J. dc.description.abstract: We present a shared industry-academic perspective on the principles and opportunities for Quality by Digital Design (QbDD) as a framework to accelerate medicines development and enable regulatory innovation for new medicines approvals. This approach exploits emerging capabilities in industrial digital technologies to achieve robust control strategies assuring product quality and patient safety whilst reducing development time/costs, improving research and development efficiency, embedding sustainability into new products and processes, and promoting supply chain resilience. Key QbDD drivers include the opportunity for new scientific understanding and advanced simulation and model-driven, automated experimental approaches. QbDD accelerates the identification and exploration of more robust design spaces. Opportunities to optimise multiple objectives emerge in route selection, manufacturability and sustainability whilst assuring product quality. Challenges to QbDD adoption include siloed data and information sources across development stages, gaps in predictive capabilities, and the current extensive reliance on empirical knowledge and judgement. These challenges can be addressed via QbDD workflows; model-driven experimental design to collect and structure findable, accessible, interoperable and reusable (FAIR) data; and chemistry, manufacturing and control ontologies for shareable and reusable knowledge. Additionally, improved product, process, and performance predictive tools must be developed and exploited to provide a holistic end-to-end development approach. dc.description: open access article

  • dc.title: Enhancing Process Control and Quality in Amorphous Solid Dispersions Using In-Line UV鈥揤is Monitoring of L* as a Real-Time Response dc.contributor.author: Bezerra, Mariana; Almeida, Juan; de Castro, Matheus; Grootveld, Martin; Schlindwein, W. S. dc.description.abstract: Background: This study demonstrates the application of the sequential design of experiments (DoE) approach within the quality by design (QbD) framework to optimize extrusion processes through screening, optimization, and robustness testing. Methods: An in-line UV鈥揤is process analytical technology (PAT) system was successfully employed to monitor critical quality attributes (CQAs) of piroxicam amorphous solid dispersion (ASD) extrusion products, specifically lightness (L*). Results: L* measurement proved highly effective for ensuring the quality and uniformity of ASDs, offering real-time insights into their physical appearance and process stability. Small variations in L* acted as early indicators of processing issues, such as phase separation or bubble formation, enabling timely intervention. This straightforward and rapid technique supports real-time process monitoring and control, allowing automated adjustments to maintain product consistency and quality. By adopting this strategy, manufacturers can minimize variability, reduce waste, and ensure adherence to quality target product profiles (QTPPs). Conclusions: Overall, this study highlights the value of in-line UV鈥揤is spectroscopy as a PAT tool in hot melt extrusion, enhancing CQA assessment and advancing the efficiency and reliability of ASD manufacturing. dc.description: open access article

  • dc.title: Optimizing extrusion processes and understanding conformational changes in itraconazole amorphous solid dispersions using in-line UV鈥揤is spectroscopy and QbD principles dc.contributor.author: Triboandas, Hetvi; Bezerra, M.; Almeida, J.; De Castro, M.; Santos, B.; Schlindwein, W. S. dc.description.abstract: This paper presents a comprehensive investigation of the manufacturing of itraconazole (ITZ) amorphous solid dispersions (ASDs) with Kolllidon庐 VA64 (KVA64) using hot-melt extrusion (HME) and in-line process monitoring, employing a Quality by Design (QbD) approach. A sequential Design of Experiments (DoE) strategy was utilized to optimize the manufacturing process, with in-line UV鈥揤is spectroscopy providing real-time monitoring. The first DoE used a fractional factorial screening design to evaluate critical process parameters (CPPs), revealing that ITZ concentration had the most significant impact on the product quality attributes. The second DoE, employing a central composite design, explored the interactions between feed rate and screw speed, using torque and absorbance at 370 nm as responses to develop a design space. Validation studies confirmed process robustness across multiple days, with stable in-line UV鈥揤is spectra and consistent product quality using 30 % ITZ, 300 rpm, 150 掳C and 7 g/min as the optimized process conditions. Theoretical and experimental analyses indicated that shifts in UV鈥揤is spectra at different ITZ concentrations were due to conformational changes in ITZ, which were confirmed through density functional theory (DFT) calculations and infrared spectroscopy. This work offers novel insights into the production and monitoring of ITZ-KVA64-ASDs, demonstrating that in-line UV鈥揤is spectroscopy is a powerful tool for real-time process monitoring and/or control. dc.description: open access article

  • dc.title: Itraconazole Amorphous Solid Dispersion Tablets: Formulation and Compaction Process Optimization Using Quality by Design Principles and Tools dc.contributor.author: Triboandas, Hetvi; Pitt, Kendal; Bezerra, Mariana; Ach-Hubert, Delphine; Schlindwein, W. S. dc.description.abstract: BCS Class II drugs, such as itraconazole (ITZ), exhibit poor solubility (1鈥�4 ng/mL) and so require solubility enhancement. Therefore, ITZ and Kollidon庐 VA64 (KOL) amorphous solid dispersions (ASDs) were produced using hot-melt extrusion (HME) to improve ITZ鈥檚 poor solubility. A novel strategy for tablet formulations using five inorganic salts was investigated (KCl, NaCl, KBr, KHCO3 and KH2PO4 ). These kosmotopric salts are thought to compete for water hydration near the polymer chain, hence, preventing polymer gelation and, therefore, facilitating disintegration and dissolution. Out of all the formulations, the KCl containing one demonstrated acceptable tensile strength (above 1.7 MPa), whilst providing a quick disintegration time (less than 15 min) and so was selected for further formulation development through a design of the experiment approach. Seven ITZ-KOL-ASD formulations with KCl were compacted using round and oblong punches. Round tablets were found to disintegrate under 20 min, whereas oblong tablets disintegrated within 10 min. The round tablets achieved over 80% ITZ release within 15 min, with six out of seven formulations achieving 100% ITZ release by 30 min. It was found that tablets comprising high levels of Avicel庐 pH 102 (30%) and low levels of KCl (5%) tend to fail the disintegration target due to the strong bonding capacity of Avicel庐 pH 102. The disintegration time and tensile strength responses were modeled to obtain design spaces (DSs) relevant to both round and oblong tablets. Within the DS, several formulations can be chosen, which meet the Quality Target Product Profile (QTPP) requirements for immediate-release round and oblong tablets and allow for flexibility to compact in different tablet shape to accommodate patients鈥� needs. It was concluded that the use of inorganic salts, such as KCl, is the key to producing tablets of ITZ ASDs with fast disintegration and enhanced dissolution. Overall, ITZ-KOL-ASD tablet formulations, which meet the QTPP, were achieved in this study with the aid of Quality by Design (QbD) principles for formulation and compaction process development and optimization. dc.description: open access article

  • dc.title: Development and Validation of an In鈥怢ine API Quantification Method Using AQbD Principles Based on UV鈥怴is Spectroscopy to Monitor and Optimise Continuous Hot Melt Extrusion Process dc.contributor.author: Almeida, Juan; Bezerra, Mariana; Markl, Daniel; Berghaus, Andreas; Borman, Phil; Schlindwein, W. S. dc.description.abstract: A key principle of developing a new medicine is that quality should be built in, with a thorough understanding of the product and the manufacturing process supported by appropriate process controls. Quality by design principles that have been established for the development of drug products/substances can equally be applied to the development of analytical procedures. This paper presents the development and validation of a quantitative method to predict the concentration of piroxicam in Kollidon庐 VA 64 during hot melt extrusion using analytical quality by design principles. An analytical target profile was established for the piroxicam content and a novel in鈥恖ine analytical procedure was developed using predictive models based on UV鈥怴is absorbance spectra collected during hot melt extrusion. Risks that impact the ability of the analytical procedure to measure piroxicam consistently were assessed using failure mode and effect analysis. The critical analytical attributes measured were colour (L* lightness, b* yellow to blue colour parameters鈥攊n鈥恜rocess critical quality attributes) that are linked to the ability to measure the API content and transmittance. The method validation was based on the accuracy profile strategy and ICH Q2(R1) validation criteria. The accuracy profile obtained with two validation sets showed that the 95% 尾鈥恊xpectation tolerance limits for all piroxicam concentration levels analysed were within the combined trueness and precision acceptance limits set at 卤5%. The method robustness was tested by evaluating the effects of screw speed (150鈥�250 rpm) and feed rate (5鈥�9 g/min) on piroxicam content around 15% w/w. In鈥恖ine UV鈥怴is spectroscopy was shown to be a robust and practical PAT tool for monitoring the piroxicam content, a critical quality attribute in a pharmaceutical HME process. dc.description: open access journal

  • dc.title: Modelling the Effect of Process Parameters on the Wet Extrusion and Spheronisation of High-Loaded Nicotinamide Pellets Using a Quality by Design Approach dc.contributor.author: Theismann, Eva-Maria; Keppler, Julia K; Owen, Martin; Schwarz, Karin; Schlindwein, W. S. dc.description.abstract: The aim of the present study was to develop an alternative process to spray granulation in order to prepare high loaded spherical nicotinamide (NAM) pellets by wet extrusion and spheronisation. Therefore, a quality by design approach was implemented to model the effect of the process parameters of the extrusion-spheronisation process on the roundness, roughness and useable yield of the obtained pellets. The obtained results were compared to spray granulated NAM particles regarding their characteristics and their release profile in vitro after the application of an ileocolon targeted shellac coating. The wet extrusion-spheronisation process was able to form highly loaded NAM pellets (80%) with a spherical shape and a high useable yield of about 90%. However, the water content range was rather narrow between 24.7% and 21.3%. The design of experiments (DoE), showed that the spheronisation conditions speed, time and load had a greater impact on the quality attributes of the pellets than the extrusion conditions screw design, screw speed and solid feed rate (hopper speed). The best results were obtained using a low load (15 g) combined with a high rotation speed (900 m/min) and a low time (3鈥�3.5 min). In comparison to spray granulated NAM pellets, the extruded NAM pellets resulted in a higher roughness and a higher useable yield (63% vs. 92%). Finally, the coating and dissolution test showed that the extruded and spheronised pellets are also suitable for a protective coating with an ileocolonic release profile. Due to its lower specific surface area, the required shellac concentration could be reduced while maintaining the release profile dc.description: Open access article

Key research outputs

 

Research interests/expertise

Her current research focuses on material sciences, especially polymers used in pharmaceutical applications. She supervises PhD students on projects related to improving the formulation of poorly soluble drugs and conducting studies using various methods for amorphisation of crystalline drug actives like hot melt extrusion. She has extensive knowledge in Pharmaceutical Quality by Design practices applied to product development and manufacture.

Areas of teaching

  • Quality by Design Principles and Tools

  •  Pharmaceutical Materials Sciences

  • Process Analytical Technology

  • Hot Melt ExtrusionPharmaceutical Product Development and Manufacture

Qualifications

  • PhD, MSc, ChemEng

制服无码 taught

  •  BSc Pharmaceutical and Cosmetic Science,
  •  Full time MSc Pharmaceutical Quality by Design,
  •  Distance learning in MSc Quality by Design for the Pharmaceutical Industry

Honours and awards

 

Membership of external committees

Member of the CMAC Advisory Board at University of Strathclyde

Membership of professional associations and societies

  •  Member of the Academy of Pharmaceutical Sciences and Regulatory Focus Group
  •  Member of the International Society of Pharmaceutical Engineering and Modelling Focus Group

Projects

 Contimuous manufacture of amorphous dispersions of porrly soluble drugs (2017 to date)

In-line process analytical technology for process monitoring (2028 to date)

Amorphous solid dispersion solubility predictions (2020 to date)

Forthcoming events

Tabletting School 2025 meeting at Leicester, 17-18th June 2025

A Hands-On Approach to Mastering Tablet Production

Conference attendance

Bezerra, M.; Muirhead, G.; Berghaus, A.; Schlindwein, W., Enabling Rapid Product Development with in-line UV-Vis Spectroscopy as PAT tool for Hot Melt Extrusion: A case study, The Ninth pan-European Conference on PAT and QbD Sciences, EuFEPS, Manchester, May 2018

Almeida, J.; Bezerra, M.; Berghaus, A.; Markl, D.; Zeitler, A.; Muirhead, G., and Schlindwein, W., Building Predictive Models for in-line UV-Vis Spectroscopy to Monitor Continuous Pharmaceutical Hot Melt Extrusion Processes, 3rd International Symposium on Continuous Manufacturing Processes, London October 2018.

 Triboandas, H.; Schlindwein, W., Continuous manufacture and monitoring of itraconazole amorphous solid dispersions by hot melt extrusion using in-line UV-Vis spectroscopy, UkPharm Sci, APS meeting, Greenwich, 11-13 Sep 2019.

 Bezerra, M., Almeida, J., Triboandas, H., Berghaus, A., Parekh, R., Whitaker, D., Mack, J, and Schlindwein, W., HME process optimisation with in-line UV-Vis spectroscopy and machine learning algorithm, PBP world meeting, Austria, 23-26 March 2020.

Bezerra, M., Almeida, J., de Castro, M., Grootveld, M., and Schlindwein, W. Hot-Melt extrusion monitoring through In-line UV-Vis spectroscopy: challenging the framework using QbD, APS Annual Conference, Huddersfield, Sep 2024.

 de Castro, M, Smith, S., Khurana, J., Cordeiro, S. and Schlindwein, W., New Insights into Ibuprofen Polymorph Interconversion: Addressing Unresolved Dynamics, APS Annual Conference, Huddersfield, Sep 2024.

Recent research outputs

  1. Almeida, J., Bezerra, M., Markl, D., Berghaus, A., Borman, P. and Schlindwein, W., Development and Validation of an in-line API Quantification Method using AQbD Principles based on UV-Vis Spectroscopy to Monitor and Optimise Continuous Hot Melt Extrusion Process, Pharmaceutics, 12(2), 150 (2020) .
  2. Triboandas, Hetvi; Pitt, Kendal; Bezerra, Mariana; Ach-Hubert, Delphine; Schlindwein, Walkiria, (2022), Itraconazole Amorphous Solid Dispersion Tablets: Formulation and Compaction Process Optimization Using Quality by Design Principles and Tools, Pharmaceutics, 14(11) 2398,
  3. Triboandas, H., Bezerra, M., Almeida, J., de Castro, M., Santos, B.A.M.C. and Schlindwein, W. (2024) Optimizing extrusion processes and understanding conformational changes in itraconazole amorphous solid dispersions using in-line UV–Vis spectroscopy and QbD principles. International Journal of Pharmaceutics: X, 8, pp. 100308.
  4. Bezerra, M.; Almeida, J.; de Castro, M.; Grootveld, M.; Schlindwein,W. Enhancing Process Control and Quality in Amorphous Solid Dispersions Using In-Line UV–Vis Monitoring of L* as a Real-Time Response. Pharmaceutics (2025), 17, 151. .

 

Key articles information

The development of amorphous solid dispersions (ASDs) via hot melt extrusion (HME) has made significant progress and is increasingly recognized as a valuable technique inpharmaceutical formulation. ASDs improve the solubility and bioavailability ofpoorly water-soluble drugs by transforming them into an amorphous state, which is generallymore soluble than their crystalline counterparts. HME is especially useful inthis area because it efficiently disperses active pharmaceutical ingredients (APIs) withina polymer matrix through the application of heat and mechanical shear. Its versatility allows for continuous processing, the creation of various dosage forms (like films,tablets, and granules), solvent free process, and enhanced scalability. 

Over the past two decades, regulatory authorities have collaborated with industry toadvance changes in the quality paradigm, aiming to understand pharmaceutical processesand product quality more comprehensively. This new approach, often referred to as the’enhanced’ approach or pharmaceutical quality by design (QbD), encourages innovation across the pharmaceutical lifecycle.

The research carried out in the last 5 years show the potential of QbD approaches using continuous extrusion to advance the field of process analytical technology by offering a robust, real-time solution for ensuring product quality and optimizing manufacturing processes.

Consultancy work

  Product Development – company RB (2022)

The project aimed to create solid dispersions in the form of powders and pellets using the hot melt extrusion method. It involved six different workstreams, each focused on a different active ingredient.

In-line PAT for cleaning validation – company Kindeva (2022/23)

The project aimed to investigate the feasibility of UV-Vis spectrophotometry in transmission configuration for the process control of pharmaceutical cleaning, batching and manufacturing.

Fast screening methods to develop amorphous drug products via hot melt extrusion – company RB (2021/22)

The project focused on developing methods for formulation optimisation and scall up manufacturing methods.

Current research students

  • Matheus de Castro – PhD student, 1st supervisor (2024/27)
  • Chuhong Cheng – PhD student, 2nd supervisor (2024/27)

Externally funded research grants information

Industry funded project: Smart manufacturing platform for innovative oral delivery of amorphous drug substances (£120 k, PI – 2024/27)

This PhD project focuses on creating a new type of ibuprofen tablet that dissolves quickly in your mouth. The main goal is to explore how using a special form of ibuprofen (called "amorphous") can help solve problems with current medicines. This could lead to better manufacturing processes (like easier handling of the powder) and improved results for patients, such as better absorption of the drug and a better taste.

EPSRC grant: Mechanistic Multiscale Modelling of Drug Release from Immediate Release Tablets (£1.1 M, Co-I – 2024/27)

This is an EPSRC project lead by DMU in collaboration with University of Surrey. The aim of the project is to develop first principles model to predict drug release profile from an IR tablet.

Innovate UK grant: A Regulatory Science Network for the Digital Transformation of Medicines Development and Manufacturing (£1 M CoI – 2024/25)

The proposed project aims to generate research and insights to help modernize the way medicines are developed and made in the pharmaceutical industry. It focuses on using data science, including artificial intelligence (AI) and predictive models, to improve the processes of creating and manufacturing medicines, especially in the health and life sciences fields. This project is in collaboration with University of Strathclyde, and CCDC Cambridge.

Published patents

Novel Composition 2022 - International Publication number W O 2022/185073 Al

This invention is directed to a novel pharmaceutically active ingredient-containing composition. In particular, the present invention is directed to an NSAID-containing 5 composition in which the NSAID is in an amorphous form.

 

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