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  • Open Access

Optimal switching strategies in multidrug therapies for chronic diseases

Juan Magalang1,2, Javier Aguilar3, Jose Perico Esguerra4, Édgar Roldán5,*, and Daniel Sanchez-Taltavull1,†

  • *Contact author: edgar@ictp.it
  • Contact author: daniel.sanchez@unibe.ch

Phys. Rev. E 112, 034408 – Published 10 September, 2025

DOI: https://doi.org/10.1103/htck-mcby

Abstract

Antimicrobial resistance is a threat to public health with millions of deaths linked to drug-resistant infections every year. To mitigate resistance, common strategies that are used are combination therapies and therapy switching. However, the stochastic nature of pathogenic mutation makes the optimization of these strategies challenging. Here, we propose a two-scale stochastic model that considers the effective evolution of therapies in a multidimensional efficacy space, where each dimension represents the efficacy of a specific drug in the therapy. The diffusion of therapies within this space is subject to stochastic resets, representing therapy switches. The boundaries of the space, inferred from coarser pathogen-host dynamics, can be either reflecting or absorbing. Reflecting boundaries impede full recovery of the host, while absorbing boundaries represent the development of antimicrobial resistance, leading to therapy failure. We derive analytical expressions for the average absorption times, accounting for both continuous and discrete genomic changes using the frameworks of Langevin and master equations, respectively. These expressions allow us to evaluate the relevance of times between drug switches and the number of simultaneous drugs in relation to typical timescales for drug resistance development. To study realistic therapy scenarios, we impose constraints on the number of administered therapies and/or their costs, which reveals nontrivial optimal drug-switching protocols that maximize the time before antimicrobial resistance develops while reducing therapy costs. Finally, we extend the model to consider single-cell heterogeneity to accurately capture the effects of individual mutations that result in drug resistance.

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References (84)

  1. C. J. L. Murray et al., Lancet 399, 629 (2022).
  2. D. Liebenberg, B. G. Gordhan, and B. D. Kana, Front. Cell. Infect. Microbiol. 12, 943545 (2022).
  3. A. N. Phillips, J. Stover, V. Cambiano, F. Nakagawa, M. R. Jordan, D. Pillay, M. Doherty, P. Revill, and S. Bertagnolio, J. Infect. Dis. 215, 1362 (2017).
  4. K. H. Mayer, H. Drechsler and W. G. Powderly, Clin. Infect. Dis. 35, 1219 (2002).
  5. N. Vasan, J. Baselga, and D. M. Hyman, Nature (London) 575, 299 (2019).
  6. A. Catalano, D. Iacopetta, J. Ceramella, D. Scumaci, F. Giuzio, C. Saturnino, S. Aquaro, C. Rosano, and M. S. Sinicropi, Molecules 27, 616 (2022).
  7. J. Maltas, D. S. Tadele, A. Durmaz, C. D. McFarland, M. Hinczewski, and J. G. Scott, PRX Life 2, 023010 (2024).
  8. Y. Wu, X. Shi, X. Yao, and X. Du, Immun. Inflammation Dis. 11, e850 (2023).
  9. N. R. Naylor, R. Atun, N. Zhu, K. Kulasabanathan, S. Silva, A. Chatterjee, G. M. Knight, and J. V. Robotham, Antimicrob. Resist. Infect. Control 7, 58 (2018).
  10. J. O'Neill, Tackling Drug-Resistant Infections Globally: Final Report and Recommendations (Government of the United Kingdom, Wellcome Trust, London, 2016).
  11. B. J. Langford, M. So, M. Simeonova, V. Leung, J. Lo, T. Kan, S. Raybardhan, M. E. Sapin, K. Mponponsuo, A. Farrell et al., Lancet Microbe 4, e179 (2023).
  12. M. Baym, L. K. Stone, and R. Kishony, Science 351, aad3292 (2016).
  13. M. Tyers and G. D. Wright, Nat. Rev. Microbiol. 17, 141 (2019).
  14. V. I. Band, D. A. Hufnagel, S. Jaggavarapu, E. X. Sherman, J. E. Wozniak, S. W. Satola, M. M. Farley, J. T. Jacob, E. M. Burd, and D. S. Weiss, Nat. Microbiol. 4, 1627 (2019).
  15. A. D. Haas, O. Keiser, E. Balestre, S. Brown, E. Bissagnene, C. Chimbetete, F. Dabis, M.-A. Davies, C. J. Hoffmann, P. Oyaro, R. Parkes-Ratanshi, S. J. Reynolds, I. Sikazwe, K. Wools-Kaloustian, D. M. Zannou, G. Wandeler, and M. Egger, Lancet HIV 2, e271 (2015).
  16. O. Keiser, P. MacPhail, A. Boulle, R. Wood, M. Schechter, F. Dabis, E. Sprinz, and M. Egger, Trop. Med. Int. Health 14, 1220 (2009).
  17. S. J. Reynolds, G. Nakigozi, K. Newell, A. Ndyanabo, R. Galiwongo, I. Boaz, T. C. Quinn, R. Gray, M. Wawer, and D. Serwadda, AIDS 23, 697 (2009).
  18. I. Davidson, H. Beardsell, B. Smith, S. Mandalia, M. Bower, B. Gazzard, M. Nelson, and J. Stebbing, Antiviral Res. 86, 227 (2010).
  19. M. G. Kirby, P. Allchorne, T. Appanna, P. Davey, R. Gledhill, J. S. A. Green, D. Greene, and D. J. Rosario, Int. J. Clin. Pract. 74, (2019).
  20. F. Pinheiro, O. Warsi, D. I. Andersson, and M. Lässig, Nat. Ecol. Evol. 5, 677 (2021).
  21. T. Lee, S. Bonhoeffer, and M. Penny, Results Phys. 34, 105181 (2022).
  22. L. Rong and A. S. Perelson, PLoS Comput. Biol. 5, e1000533 (2009).
  23. O. Sharomi and A. Gumel, J. Biol. Dyn. 2, 323 (2008).
  24. A. M. Niewiadomska, B. Jayabalasingham, J. C. Seidman, L. Willem, B. Grenfell, D. Spiro, and C. Viboud, BMC Med. 17, 81 (2019).
  25. H. Heesterbeek, R. M. Anderson, V. Andreasen, S. Bansal, D. De Angelis, C. Dye, K. T. D. Eames, W. J. Edmunds, S. D. W. Frost, S. Funk, T. D. Hollingsworth, T. House, V. Isham, P. Klepac, J. Lessler, J. O. Lloyd-Smith, C. J. E. Metcalf, D. Mollison, L. Pellis, J. R. C. Pulliam et al., Science 347, aaa4339 (2015).
  26. N. T. Hillock, T. L. Merlin, J. Turnidge, and J. Karnon, Appl. Health Econ. Health Policy 20, 479 (2022).
  27. S. C. Manrubia, Curr. Opin. Virol. 2, 531 (2012).
  28. A. Papkou, L. Garcia-Pastor, J. A. Escudero, and A. Wagner, Science 382, eadh3860 (2023).
  29. A. P. Duncan Callaway, Bull. Math. Biol. 64, 29 (2002).
  30. M. R. Evans and S. N. Majumdar, Phys. Rev. Lett. 106, 160601 (2011).
  31. M. R. Evans, S. N. Majumdar, and G. Schehr, J. Phys. A: Math. Theor. 53, 193001 (2020).
  32. T. Rotbart, S. Reuveni, and M. Urbakh, Phys. Rev. E 92, 060101(R) (2015).
  33. É. Roldán, A. Lisica, D. Sánchez-Taltavull, and S. W. Grill, Phys. Rev. E 93, 062411 (2016).
  34. A. Lisica, C. Engel, M. Jahnel, É. Roldán, E. A. Galburt, P. Cramer, and S. W. Grill, Proc. Natl. Acad. Sci. USA 113, 2946 (2016).
  35. P. C. Bressloff, J. Phys. A: Math. Theor. 53, 355001 (2020).
  36. J. Wang, K. Zhang, L. Xu, and E. Wang, Proc. Natl. Acad. Sci. USA 108, 8257 (2011).
  37. M. R. Evans and S. N. Majumdar, J. Phys. A: Math. Theor. 44, 435001 (2011).
  38. A. Pal and V. V. Prasad, Phys. Rev. E 99, 032123 (2019).
  39. L. Kuśmierz and E. Gudowska-Nowak, Phys. Rev. E 92, 052127 (2015).
  40. A. Pal and S. Reuveni, Phys. Rev. Lett. 118, 030603 (2017).
  41. D. Das and L. Giuggioli, J. Phys. A: Math. Theor. 55, 424004 (2022).
  42. A. Ramoso, J. Magalang, D. Sánchez-Taltavull, J. Esguerra, and E. Roldán, Europhys. Lett. 132, 50003 (2020).
  43. R. Solé, J. Sardanyés, and S. F. Elena, Rep. Prog. Phys. 84, 115901 (2021).
  44. M. A. Nowak and R. M. May, Math. Biosci. 106, 1 (1991).
  45. M. A. Nowak, R. M. Anderson, M. C. Boerlijst, S. Bonhoeffer, R. M. May, A. J. McMichael, S. M. Wolinsky, K. J. Kunstman, J. T. Safrit, R. A. Koup, A. U. Neumann, and B. T. M. Korber, Science 274, 1008 (1996).
  46. W. R. Greco, G. Bravo, and J. C. Parsons, Pharmacol. Rev. 47, 331 (1995).
  47. C. I. Bliss, Ann. Appl. Biol. 26, 585 (1939).
  48. R. Roemhild, T. Bollenbach, and D. I. Andersson, Nat. Rev. Microbiol. 20, 478 (2022).
  49. S. Redner, A Guide to First-Passage Processes (Cambridge University Press, Cambridge, UK, 2001).
  50. D. L. Dy and J. P. Esguerra, Phys. Rev. E 88, 012121 (2013).
  51. C. Gardiner, in Stochastic Methods, Springer series in synergetics (Springer, Berlin, 2008), pp. 1–22.
  52. L. Giuggioli, S. Sarvaharman, D. Das, D. Marris, and T. Kay, Multi-target search in bounded and heterogeneous environments: A lattice random walk perspective, Target Search Problems (Springer, 2024), pp. 107–133.
  53. N. G. V. Kampen, Stochastic Processes in Physics and Chemistry (Elsevier, Amsterdam, 2007).
  54. D. T. Gillespie, J. Phys. Chem. 81, 2340 (1977).
  55. D. T. Gillespie, J. Chem. Phys. 72, 5363 (1980).
  56. P. E. Harunari, A. Dutta, M. Polettini, and E. Roldán, Phys. Rev. X 12, 041026 (2022).
  57. J. van der Meer, B. Ertel, and U. Seifert, Phys. Rev. X 12, 031025 (2022).
  58. K. Sekimoto, arXiv:2110.02216.
  59. P. Jolakoski, A. Pal, T. Sandev, L. Kocarev, R. Metzler, and V. Stojkoski, Chaos Solitons Fractals 175, 113921 (2023).
  60. R. Toral and P. Colet, Stochastic Numerical Methods, edited by R. Toral and P. Colet (Wiley, New York, 2014), Vol. 111, pp. 1009–1010.
  61. J. C. Sunil, R. A. Blythe, M. R. Evans, and S. N. Majumdar, J. Phys. A: Math. Theor. 56, 395001 (2023).
  62. B. De Bruyne and F. Mori, Phys. Rev. Res. 5, 013122 (2023).
  63. J. Magalang, R. Turin, J. Aguilar, L. Colombani, D. Sanchez-Taltavull, and R. Gatto, Phys. Rev. E 111, 054117 (2025).
  64. S. Baral, R. Raja, P. Sen, and N. M. Dixit, WIREs Syst. Biol. Med. 11, e1446 (2019).
  65. M. C. F. Prosperi, R. D'Autilia, F. Incardona, A. De Luca, M. Zazzi, and G. Ulivi, Bioinformatics 25, 1040 (2009).
  66. D. I. Andersson, H. Nicoloff, and K. Hjort, Nat. Rev. Microbiol. 17, 479 (2019).
  67. H. Nicoloff, K. Hjort, B. R. Levin, and D. I. Andersson, Nat. Microbiol. 4, 504 (2019).
  68. R. Roemhild and H. Schulenburg, Evol. Med. Public Health 2019, 37 (2019).
  69. C. E. H. Rosenkilde, C. Munck, A. Porse, M. Linkevicius, D. I. Andersson, and M. O. A. Sommer, Nat. Commun. 10, 618 (2019).
  70. L. Imamovic and M. O. A. Sommer, Sci. Transl. Med. 5, 204ra132 (2013).
  71. A. Batra, R. Roemhild, E. Rousseau, S. Franzenburg, S. Niemann, and H. Schulenburg, eLife 10, e68876 (2021).
  72. M. Oette, E. Schülter, M. Rosen-Zvi, Y. Peres, M. Zazzi, A. Sönnerborg, D. Struck, A. Altmann, R. Kaiser, and the EuResist Network Study Group, Intervirology 55, 160 (2012) .
  73. J. Sochman and M. Podzimkova, Int. J. Cardiol. 99, 145 (2005).
  74. A. L. Avanceña and D. W. Hutton, Value Health 23, 1509 (2020).
  75. M. L. Brandeau and G. S. Zaric, Health Care Manage. Sci. 12, 27 (2009).
  76. S. Duwal, S. Winkelmann, C. Schütte, and M. von Kleist, PLoS Comput. Biol. 11, e1004200 (2015).
  77. D. Chen, G. Liu, H. Du, J. Wee, R. Wang, J. Chen, J. Shen, and G.-W. Wei, ArXiv (2024).
  78. P. Lamirande, E. A. Gaffney, M. Gertz, P. K. Maini, J. R. Crawshaw, and A. Caruso, Invest. Ophthalmol. Vis. Sci. 65 (2024).
  79. H. E. Lebovitz and M. A. Banerji, Eur. J. Pharmacol. 490, 135 (2004).
  80. F. Braido, F. Lavorini, F. Blasi, I. Baiardini, and G. W. Canonica, Int. J. Chronic Obstruct. Pulm. Dis. 2015, 2601 (2015).
  81. M. C. S. Wong, W. W. S. Tam, C. S. K. Cheung, E. L. H. Tong, A. C. H. Sek, G. John, N. T. Cheung, B. P. Y. Yan, C. M. Yu, S. Leeder, and S. Griffiths, PLoS One 8, e53625 (2013).
  82. J. Václavík, P. Vysočanová, J. Seidlerová, P. Zajíček, O. Petrák, J. Dlask, and J. Krýza, Medicine 93, e168 (2014).
  83. V. G. Athyros, K. Tziomalos, A. Karagiannis, and D. P. Mikhailidis, Expert Opin. Pharmacother. 11, 2943 (2010).
  84. https://github.com/jarmsmagalang/optimal_therapy_switching.

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