Clotrimazole-loaded PLGA microparticles for local drug delivery to the vagina: Shape does matter

Abstract

Background: Intravaginal drug administration is the most promising strategy for treating vaginal infections to protect women's health, such as vulvovaginal candidiasis (VVC). However, conventional vaginal formulations in the clinic face challenges such as drug leakage and low bioavailability due to the mucus barrier and vaginal self-cleaning behavior. To address these limitations, we designed and optimized clotrimazole-loaded PLGA non-spherical microparticles (CPNMs) for vaginal drug delivery.

Methods: CPNMs and clotrimazole-loaded PLGA porous microspheres (CPMs) were prepared by the double emulsion-solvent evaporation method. The physicochemical features and in vitro drug release kinetics were characterized, and the effect of shape on drug delivery were also investigated. After intravaginal administration of CPMs and CPNMs, the pharmacokinetics and biocompatibility in the vagina of mice were studied.

Results: Both CPMs and CPNMs exhibited sustained release features in vitro. Initially, there was a rapid release within the first 24 h and the cumulative release of CPMs and CPNMs was 46.55% and 56.89% over 7 days, respectively. Compared to CPMs, CPNMs demonstrated an extended drug release in vivo, maintaining a residence duration of at least 72 h, which was beneficial for clotrimazole delivery at a high concentration in the vagina of mice. Histological evaluation demonstrated the low cytotoxicity and good biocompatibility of CPNMs, with no obvious damage to vaginal epithelial cells.

Conclusion: This vaginal drug delivery system offers potential applications for managing VVC, along with other health concerns in women.

Keywords

clotrimazole / pharmacokinetics / PLGA microparticles / shape effect / vaginal drug delivery

References

[1] Sobel JD. Vulvovaginal candidosis. Lancet. 2007; 369(9577): 1961-1971.

[2] Workowski KA, Bachmann LH, Chan PA, et al. Sexually transmitted infections treatment guidelines, 2021. MMWR Recomm Rep. 2021; 70(4): 1-187.

[3] Denning DW, Kneale M, Sobel JD, Rautemaa-Richardson R. Global burden of recurrent vulvovaginal candidiasis: a systematic review. Lancet Infect Dis. 2018; 18(11): e339-e347.

[4] Swingle KL, Ricciardi AS, Peranteau WH, Mitchell MJ. Delivery technologies for women's health applications. Nat Rev Bioeng. 2023; 1(6): 408-425.

[5] Johal HS, Garg T, Rath G, Goyal AK. Advanced topical drug delivery system for the management of vaginal candidiasis. Drug Deliv. 2016; 23(2): 550-563.

[6] Nappi RE, Liekens G, Brandenburg U. Attitudes, perceptions and knowledge about the vagina: the International Vagina Dialogue Survey. Contraception. 2006; 73(5): 493-500.

[7] Hussain A, Ahsan F. The vagina as a route for systemic drug delivery. J Control Release. 2005; 103(2): 301-313.

[8] Jaworska-Krych D, Gosecka M, Gosecki M, et al. Enhanced solubility and bioavailability of clotrimazole in aqueous solutions with hydrophobized hyperbranched Polyglycidol for improved antifungal activity. ACS Appl Mater Interfaces. 2024; 16(15): 18434-18448.

[9] Das Neves J, Notario-Pérez F, Sarmento B. Women-specific routes of administration for drugs: a critical overview. Adv Drug Deliv Rev. 2021; 176:113865.

[10] Valamla B, Thakor P, Phuse R. Engineering drug delivery systems to overcome the vaginal mucosal barrier: current understanding and research agenda of mucoadhesive formulations of vaginal delivery. J Drug Deliv Sci Technol. 2022; 70:103162.

[11] Caramella CM, Rossi S, Ferrari F, Bonferoni MC, Sandri G. Mucoadhesive and thermogelling systems for vaginal drug delivery. Adv Drug Deliv Rev. 2015; 92: 39-52.

[12] Lai SK, O'Hanlon DE, Harrold S, et al. Rapid transport of large polymeric nanoparticles in fresh undiluted human mucus. Proc Natl Acad Sci U S A. 2007; 104(5): 1482-1487.

[13] Ensign LM, Tang BC, Wang YY, et al. Mucus-penetrating nanoparticles for vaginal drug delivery protect against herpes simplex virus. Sci Transl Med. 2012; 4(138):138ra79.

[14] Wang YY, Lai SK, Suk JS, Pace A, Cone R, Hanes J. Addressing the PEG mucoadhesivity paradox to engineer nanoparticles that “slip” through the human mucus barrier. Angew Chem Int Ed Engl. 2008; 47(50): 9726-9729.

[15] Lai SK, Wang YY, Hida K, Cone R, Hanes J. Nanoparticles reveal that human cervicovaginal mucus is riddled with pores larger than viruses. Proc Natl Acad Sci U S A. 2010; 107(2): 598-603.

[16] Bao C, Liu B, Li B, et al. Enhanced transport of shape and rigidity-tuned α-lactalbumin nanotubes across intestinal mucus and cellular barriers. Nano Lett. 2020; 20(2): 1352-1361.

[17] Melo CM, Cardoso JF, Perassoli FB, et al. Amphotericin B-loaded Eudragit RL100 nanoparticles coated with hyaluronic acid for the treatment of vulvovaginal candidiasis. Carbohydr Polym. 2020; 230:115608.

[18] Araujo VHS, de Souza MPC, Carvalho GC, Duarte JL, Chorilli M. Chitosan-based systems aimed at local application for vaginal infections. Carbohydr Polym. 2021; 261:117919.

[19] Campaña-Seoane M, Pérez-Gago A, Vázquez G, et al. Vaginal residence and pharmacokinetic preclinical study of topical vaginal mucoadhesive W/S emulsions containing ciprofloxacin. Int J Pharm. 2019; 554: 276-283.

[20] Wang Y, Wang Z, Li Q, et al. A “three-in-one” thermosensitive gel system that enhances mucus and biofilm penetration for the treatment of vulvovaginal candidiasis. J Control Release. 2025; 382:113666.

[21] Martín-Villena MJ, Fernández-Campos F, Calpena-Campmany AC, Bozal-de Febrer N, Ruiz-Martínez MA, Clares-Naveros B. Novel microparticulate systems for the vaginal delivery of nystatin: development and characterization. Carbohydr Polym. 2013; 94(1): 1-11.

[22] Souza RO, Henrique de Lima T, Oréfice RL, et al. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers: an alternative therapy scheme for local treatment of vulvovaginal candidiasis. J Pharm Sci. 2018; 107(10): 2674-2685.

[23] Jordan C, Shuvaev VV, Bailey M, Muzykantov VR, Dziubla TD. The role of carrier geometry in overcoming biological barriers to drug delivery. Curr Pharm des. 2016; 22(9): 1259-1273.

[24] Etter EL, Mei KC, Nguyen J. Delivering more for less: nanosized, minimal-carrier and pharmacoactive drug delivery systems. Adv Drug Deliv Rev. 2021; 179:113994.

[25] Champion JA, Mitragotri S. Role of target geometry in phagocytosis. Proc Natl Acad Sci U S A. 2006; 103(13): 4930-4934.

[26] Li M, Ai M, Yang Y, et al. Silk-coated dexamethasone non-spherical microcrystals for local drug delivery to inner ear. Eur J Pharm Sci. 2020; 150:105336.

[27] Wang D, Zhang X, Wang Z, et al. Intratympanic dexamethasone microcrystals/lidocaine-loaded PLGA non-spherical microparticles for local drug delivery to the inner ear. Animal Model Exp Med. 2025; 8(10): 1813-1823.

[28] Jiang Z, Tang H, Xiong Q, Li M, Dai Y, Zhou Z. Placental cell translocation of folate-conjugated pullulan acetate non-spherical nanoparticles. Colloids Surf B Biointerfaces. 2022; 216:112553.

[29] Tonglairoum P, Ngawhirunpat T, Rojanarata T, Panomsuk S, Kaomongkolgit R, Opanasopit P. Fabrication of mucoadhesive chitosan coated polyvinylpyrrolidone/cyclodextrin/clotrimazole sandwich patches for oral candidiasis. Carbohydr Polym. 2015; 132: 173-179.

[30] Crowley PD, Gallagher HC. Clotrimazole as a pharmaceutical: past, present and future. J Appl Microbiol. 2014; 117(3): 611-617.

[31] Tonglairoum P, Ngawhirunpat T, Rojanarata T, Kaomongkolgit R, Opanasopit P. Fast-acting clotrimazole composited PVP/HPβCD nanofibers for oral candidiasis application. Pharm Res. 2014; 31(8): 1893-1906.

[32] Danhier F, Ansorena E, Silva JM, Coco R, Le Breton A, Préat V. PLGA-based nanoparticles: an overview of biomedical applications. J Control Release. 2012; 161(2): 505-522.

[33] Li R, Li X, Liu L, Zhou Z, Tang H, Zhang Q. High-yield fabrication of PLGA non-spherical microarchitectures by emulsion-solvent evaporation method. Macromol Rapid Commun. 2010; 31(22): 1981-1986.

[34] Zhang J, Wang J, Qiao F, et al. Polymeric non-spherical coarse microparticles fabricated by double emulsion-solvent evaporation for simvastatin delivery. Colloids Surf B Biointerfaces. 2021; 199:111560.

[35] Tiboni M, Campana R, Frangipani E, Casettari L. 3D printed clotrimazole intravaginal ring for the treatment of recurrent vaginal candidiasis. Int J Pharm. 2021; 596:120290.

[36] Gao C, Yuan W, Wang D, Zhang X, Zhang T, Zhou Z. Adipose-derived mesenchymal stem cell-incorporated PLLA porous microspheres for cartilage regeneration. Animal Model Exp Med. 2024; 7(5): 685-695.

[37] Das Neves J, Araújo F, Andrade F, Amiji M, Bahia MF, Sarmento B. Biodistribution and pharmacokinetics of dapivirine-loaded nanoparticles after vaginal delivery in mice. Pharm Res. 2014; 31(7): 1834-1845.

[38] Wang P, Wang M, Wei X, et al. In vitro and in vivo degradation profile, biocompatibility of poly-L-lactic acid porous microspheres. Int J Biol Macromol. 2024; 272(pt 2):132876.

[39] Guo C, Zhang T, Tang J, Gao C, Zhou Z, Li C. Construction of PLGA porous microsphere-based artificial pancreatic islets assisted by the cell centrifugation perfusion technique. ACS Omega. 2023; 8(17): 15288-15297.

[40] Liu Y, Zhang T, Li M, et al. PLGA hybrid porous microspheres as human periodontal ligament stem cell delivery carriers for periodontal regeneration. Chem Eng J. 2021; 420:129703.

[41] Zhang P, Wang D, Zhang X, et al. Intratympanic dexamethasone microcrystal-loaded porous PLGA microspheres containing lipoic acid for combined delivery to the inner ear. J Otol. 2025; 20(3): 190-197.

[42] Martínez-Pérez B, Quintanar-Guerrero D, Tapia-Tapia M, et al. Controlled-release biodegradable nanoparticles: from preparation to vaginal applications. Eur J Pharm Sci. 2018; 115: 185-195.

[43] Ritger PL, Peppas NA. A simple equation for description of solute release II. Fickian and anomalous release from swellable devices. J Control Release. 1987; 5: 37-42.

[44] Fotouh B, Kyser AJ, Frieboes HB. Drug and therapeutic intravaginal delivery targeting diseases in the female reproductive tract: a mathematical modeling perspective. J Control Release. 2025; 384:113924.

[45] Zolnik BS, Burgess DJ. Effect of acidic pH on PLGA microsphere degradation and release. J Control Release. 2007; 122(3): 338-344.

[46] Yoo JW, Mitragotri S. Polymer particles that switch shape in response to a stimulus. Proc Natl Acad Sci U S A. 2010; 107(25): 11205-11210.

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2026 The Author(s). Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.