Dual-strategy; complexation-based solid dispersion for enhancing the solubility and dissolution rate of candesartan cilexetil
Copyright (c) 2026 Saya Latif Abdullah , Huner Kamal Omer (Author)

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
- Articles
- Submited: June 2, 2025
-
Published: August 12, 2026
Abstract
Background and objective: Candesartan cilexetil (CC), an angiotensin II receptor blocker indicated for hypertension and heart failure, is classified as a BCS Class II drug which is characterized by low aqueous solubility (0.963 ± 0.062 µg/mL) and limited oral bioavailability (14%–40%). Both factors significantly undermine its therapeutic efficacy and present challenges in formulation development. This study aimed to improve the solubility and dissolution properties of CC through two formulation techniques of solid dispersion with PVPK30 by rotavapor and inclusion complex with HPβCD by kneading.
Methods: In this study, solid dispersions and inclusion complexes were formulated at drug to polymer ratios of 1:1, 1:3, and 1:6, with corresponding physical mixtures at a 1:6 ratio. A study on saturated solubility was performed in distilled water. The best formulations—SD3 (solid dispersion with PVP K30) and IC3 (inclusion complex with HPβCD)—were subjected to further characterization. The characterizations consisting of percent drug content, in vitro drug release, Fourier Transform Infrared Spectroscopy, and Powder X-ray Diffraction were performed.
Results: SD3 and IC3 improved the solubility of CC by 21.19-fold (20.40 ± 0.139 µg/mL) and 12.22-fold (11.76 ± 0.202 µg/mL), respectively. Both exhibited high drug content—98.47% (SD3) and 98.21% (IC3)—and accomplished over 90% drug release within 15 minutes. FTIR confirmed hydrogen bonding and non-covalent interactions, however PXRD revealed diminished crystallinity and enhanced amorphization.
Conclusion: Both PVP K30-based solid dispersion via rotavapor and HPβCD-based inclusion complexation through kneading significantly improved the solubility and dissolution rate of Candesartan cilexetil, with solid dispersion demonstrating superior efficacy for enhancing oral bioavailability.
Metrics
References
- Homayun B, Lin X, Choi HJ. Challenges and recent progress in oral drug delivery systems for biopharmaceuticals. Pharmaceutics. 2019;11(3):129. https://doi.org/10.3390/pharmaceutics11030129
- Singh N, Sharma L. Enhancement in solubility of Glibenclamide and Clofibrate drugs using carbohydrate based non-ionic surfactants by micellization. Indo Am J Pharm Sci. 2017;4(2):186–92. https://doi.org/10.5281/zenodo.322915
- Abdullah Ali H, Kamal Omer H. Solubility enhancement of a poorly water‐soluble drug using hydrotropy and mixed hydrotropy‐based solid dispersion techniques. Adv Pharmacol Pharm Sci. 2022;2022(1):7161660. https://doi.org/10.1155/2022/7161660
- Kumari L, Choudhari Y, Patel P, Gupta GD, Singh D, Rosenholm JM, et al. Advancement in solubilization approaches: a step towards bioavailability enhancement of poorly soluble drugs. Life (Basel). 2023;13(5):1099. https://doi.org/10.3390/life13051099
- Kale P, Shaikh I, Bavage S, NbjjhwicI B. Review on techniques for solubility enhancement. Int J Curr Res Rev. 2021;13(17):2582. https://doi.org/10.56726/irjmets43891
- Zhang X, Xing H, Zhao Y, Ma Z. Pharmaceutical dispersion techniques for dissolution and bioavailability enhancement of poorly water-soluble drugs. Pharmaceutics. 2018;10(3):74. https://doi.org/10.3390/pharmaceutics10030074
- Singh A, Van den Mooter G. Spray drying formulation of amorphous solid dispersions. Adv Drug Deliv Rev. 2016; 100:27–50. https://doi.org/10.1016/j.addr.2015.12.009
- Yousaf AM, Qadeer A, Raza SA, Chohan TA, Shahzad Y, Din FU, et al. Influence of levodropropizine and hydroxypropyl-β-cyclodextrin association on the physicochemical characteristics of levodropropizine loaded in hydroxypropyl-β-cyclodextrin microcontainers: formulation and in vitro characterization. Polim Med. 2019;49(1):35–43. https://doi.org/10.17219/pim/111887
- Aly UF, Sarhan HAM, Ali TF, Sharkawy HAEB. Applying different techniques to improve the bioavailability of candesartan cilexetil antihypertensive drug. Drug Des Devel Ther. 2020;14:1851–65. https://doi.org/10.2147/DDDT.S248511
- Poudel S, Kim DW. Developing pH-modulated spray dried amorphous solid dispersion of candesartan cilexetil with enhanced in vitro and in vivo performance. Pharmaceutics. 2021;13(4):497. https://doi.org/10.3390/pharmaceutics13040497
- Sunkara SP, Suryadevara V, Bathula SL, Doppalapudi S, Padarthi PK, Kunam V. Formulation and evaluation of candesartan cilexetil fast dissolving tablets using inclusion complexes. Res J Pharm Technol. 2020;13(2):751–7. https://doi.org/10.5958/0974-360X.2020.00142.0
- Hamadameen HA, Qader HL, Abdullah AH. Improvement of solubility and dissolution rate of biopharmaceutical class II drug atorvastatin calcium by using an essential amino acid L-leucine. Zanco J Med Sci. 2022;26(1):67–77. https://doi.org/10.15218/zjms.2022.008
- Loh GOK, Tan YTF, Peh KK. Enhancement of norfloxacin solubility via inclusion complexation with β-cyclodextrin and its derivative hydroxypropyl-β-cyclodextrin. Asian J Pharm Sci. 2016;11(4):536–46. https://doi.org/10.1016/j.ajps.2016.02.009
- Agrawal G. Preparation of solid dispersions of ornidazole using mixed hydrotropic solubilization technique and their characterization. Int J Green Pharm. 2017;11(4). https://doi.org/10.22377/ijgp.v11i04.1349
- Sharma P, Kaur T, Singh AP. Solubility and dissolution enhancement of water insoluble drug by using different hydrophilic carriers and formulated into tablet dosage form. J Drug Deliv Ther. 2017;7(5):86–93. https://doi.org/10.22270/jddt.v7i5.1491
- Aziz GM, Al-Khedairy EBH. Solubility and dissolution enhancement of candesartan cilexetil by complexation with cyclodextrin. Int J Drug Deliv Technol. 2024;14(1):257–64. https://doi.org/10.25258/ijddt.14.1.37
- Amer AM, Allam AN, Abdallah OY. Evaluation of the discriminatory power of USP dissolution method for candesartan cilexetil tablets through testing of marketed products in Egypt. Dissolution Technol. 2018;25(4):40–6. https://doi.org/10.14227/DT250418P40
- Hussein LS, Al-Khedairy EB. Solubility and dissolution enhancement of ebastine by surface solid dispersion technique. Iraqi J Pharm Sci. 2021;30(1):122–32. https://doi.org/10.31351/vol30iss1pp122-132
- González R, Peña MÁ, Torres NS, Torrado G. Design, development, and characterization of amorphous rosuvastatin calcium tablets. PLoS One. 2022;17(3):e0265263. https://doi.org/10.1371/journal.pone.0265263
- Kamble R, Sharma S, Mehta P. Norfloxacin mixed solvency based solid dispersions: an in-vitro and in-vivo investigation. J Taibah Univ Sci. 2017;11(3):512–22. https://doi.org/10.1016/j.jtusci.2016.11.003
- Seftian M, Laksitorini MD, Sulaiman TNS. Enhancement of valsartan solubility by amorphous solid dispersion ternary system: an optimization and characterization. Res J Pharm Technol. 2024;17(8):3717–24. https://doi.org/10.52711/0974-360X.2024.00578
- Jagdale SK, Dehghan MH, Nilesh SP. Enhancement of dissolution of fenofibrate using complexation with hydroxy propyl β-cyclodextrin. Turk J Pharm Sci. 2018;16(1):48. https://doi.org/10.4274/tjps.60490
- Munir R, Hadi A, Khan SUD, Asghar S, Irfan M, Khan IU, et al. Solubility and dissolution enhancement of dexibuprofen with hydroxypropylbetacyclodextrin (HPβCD) and poloxamers (188/407) inclusion complexes: preparation and in vitro characterization. Polymers (Basel). 2022;14(3):579. https://doi.org/10.3390/polym14030579
- Ali ISM, Sajad UA, Abdul Rasool BK. Solid dispersion systems for enhanced dissolution of poorly water-soluble candesartan cilexetil: in vitro evaluation and simulated pharmacokinetics studies. PLoS One. 2024;19(6):e0303900. https://doi.org/10.1371/journal.pone.0303900
- Sankari T, Al-Hariri S. Preparation and characterization of cefuroxime axetil solid dispersions using poloxamer 188. Braz J Pharm Sci. 2019;54(4):e17644. https://doi.org/10.1590/s2175-97902018000417644
- Jakubowska E, Ciepluch N. Blend segregation in tablets manufacturing and its effect on drug content uniformity—a review. Pharmaceutics. 2021;13(11):1909. https://doi.org/10.3390/pharmaceutics13111909
- Ramadhan SA, Omer HK. The development of ternary and quaternary solid dispersion based hydrotropic blends of atorvastatin calcium: solid dispersion based hydrotropic blends. Zanco J Med Sci. 2024;28(1):95–110. https://doi.org/10.15218/zjms.2024.010
- Tran TT, Tran PH. Molecular interactions in solid dispersions of poorly water-soluble drugs. Pharmaceutics. 2020;12(8):745. https://doi.org/10.3390/pharmaceutics12080745
- Chabane A, Bouchal F, Hentabli M, Ayachi N, Slama HE, Rezgui F, et al. Investigation of the candesartan cilexetil antihypertensive drug microencapsulation by PLA‐PVP K30 biodegradable polymers: experimental optimization and release kinetics modelling. Can J Chem Eng. 2023;101(8):4446–59. https://doi.org/10.1002/cjce.24811
- Bhatia M, Devi S. Development, characterisation and evaluation of PVP K-30/PEG solid dispersion containing ketoprofen. Acta Pharm Sci. 2020;58(1). https://doi.org/10.23893/1307-2080.APS.05806
- Salih OS, Hamoddi ZM, Taher SS. Development and characterization of controlled release tablets of candesartan cilexetil/β-cyclodextrin inclusion complex. Int J Drug Deliv Technol. 2020;10(2):273–83. https://doi.org/10.25258/ijddt.10.2.15
- Gurunath S, Nanjwade BK, Patila P. Enhanced solubility and intestinal absorption of candesartan cilexetil solid dispersions using everted rat intestinal sacs. Saudi Pharm J. 2014;22(3):246. https://doi.org/10.1016/j.jsps.2013.03.006
- Madan JR, Kamate VJ, Dua K, Awasthi R. Improving the solubility of nevirapine using a hydrotropy and mixed hydrotropy based solid dispersion approach. Polym Med. 2017;47(2):83–90. https://doi.org/10.17219/pim/77093