The relationship between the efficacy of methotrexate in rheumatoid arthritis and the achieved level of its polyglutamates in erythrocytes (pilot study)

Therapeutic control of the methotrexate (MT) polyglutamates (MTPG) level in erythrocytes can be an objective marker of the effective dose of MT prescribed for rheumatoid arthritis (RA).

Objective: to assess the relationship between the level of MTPG in red blood cells and efficacy of the MT dose used by RA patients.

Subjects and methods. The study included 60 patients with RA (44 women and 16 men over 18 years) who met the criteria of the American College of Rheumatology and the European League Against Rheumatism (ACR/EULAR) 2010 and received MT ≥20 mg/week subcutaneously for ≥12 weeks. The patients were divided into two groups of comparable age, sex, alcohol intake, number of smokers, body mass index (BMI), depending on the presence (group 1; n=30) or absence (group 2; n=30) of the effect of MT, according to the EULAR efficacy criteria (DAS28). The concentration of MTPG (total MTPG and metabolites of MTPG _{1, 2, 3, 4, 5}) was determined in erythrocytes by high-performance liquid chromatography with mass spectrometric detection.

Results and discussion. It was found that the levels of total MTPG and MTPG_{1, 2, 3, 5} in erythrocytes did not differ in groups of responders and nonresponders, and the dose of MT was comparable in both groups. At the same time, the level of MTPG₄ in the first group was significantly higher (26.4±6.1 nmol/l; p=0.023) than in the second one (22.1±6.8 nmol/l). Analysis of the ROC curve showed that the values of MTPG₄ <22.5 nmol/l corresponded to the absence of effect of MT. The area under the curve was 0.672 (95% confidence interval 0.536–0.808 (p=0.022), sensitivity 77%, specificity 53.3%.

Conclusion. For effective treatment of patients with RA MT dose should provide MTPG4 level in red blood cells ≥22.5 nmol/l.

1. Goodman S. Measuring methotrexate polyglutamates.Clin Exp Rheumatol. 2010 Sep-Oct;28(5 Suppl 61):S24-6. Epub 2010 Oct 28.

2. Tishler M, Caspi D, Graff E, et al. Synovial and serum levels of methotrexate during methotrexate therapy of rheumatoid arthritis. Br J Rheumatol. 1989 Oct;28(5):422-3. doi: 10.1093/rheumatology/28.5.422

3. Bannwarth B, Pehourcq F, Schaeverbeke T, Dehais J. Clinical pharmacokinetics of low-dose pulse methotrexate in rheumatoid arthritis. Clin Pharmacokinet. 1996 Mar;30(3):194-210. doi: 10.2165/00003088-199630030-00002

4. Westerhof G, Schornagel J, Kathmann I, et al. Carrier- and receptor-mediated transport of folate antagonists targeting folatedependent enzymes: correlates of molecular-structure and biological activity. Mol Pharmacol. 1995 Sep;48(3):459-71.

5. Hasko G, Cronstein B. Regulation of inflammation by adenosine. Frontiers Immunol. 2013;4:85. doi: 10.33389/fimmunu.2013.00085

6. Wessels JAM, Huizinga TWJ, Guchelaar H-J. Recent insights in the pharmacological actions of methotrexate in the treatment of rheumatoid arthritis. Rheumatology. 2008;47(3):249-55. doi: 10.1093/rheumatology/kem279

7. Chan ESL, Cronstein BN. Methotrexate – how does it really work. Nat Rev Rheumatol. 2010;6(3):175-8. doi: 10/1038/nrrheum.2010.5

8. Nasonov EL. Methotrexate in rheumatoid arthritis – 2015: New facts and ideas. Nauchno-prakticheskaya revmatologiya = Rheumatology Science and Practice. 2015;53(4):421-33 (In Russ.). doi: 10.14412/1995-4484-2015-421-433

9. Danila MI, Hughes LB, Brown EE, et al. Measurement of erythrocyte methotrexate polyglutamate levels: ready for clinical use in rheumatoid arthritis? Curr Rheumatol Rep. 2010;12(5):342-7. doi: 10.1007/s11926-010-0120-3

10. Dalrymple J, Stamp L, O'Donnell J. Pharmacokinetics of oral methotrexate in patients with rheumatoid arthritis. Arthritis Rheum. 2008 Nov;58(11):3299-308. doi: 10.1002/art.24034

11. De Rotte MCFJ, den Boer E, de Jong PHP, et al. Methotrexate polyglutamates in erythrocytes are associated with lower diseaseactivity in patients with rheumatoid arthritis. Ann Rheum Dis. 2015;74:408-14. doi: 10.1136/annrheumdis-2013-203725

12. Fransen J, Welsing PMJ, de Keijzer RMH, van Riel PLCM. Disease Activity Scores using C-reactive protein: CRP may replace ESR in the assessment of RA disease activity. Ann Rheum Dis. 2004;62:151.

13. Miroshnichenko I, Baymeeva N. Simultaneous Determination of Antipsychotic Drugs and Their Active Metabolites by LC-MSMS and its Application to Therapeutic Drug Monitoring. J Chromatogr Sci. 2018 Jul 1;56(6):510-7. doi: 10.1093/chromsci/bmy024

14. Fransen J, van Riel PL. The Disease Activity Score and the EULAR response criteria. Clin Exp Rheumatol. 2005;23:S93-9.

15. De Rotte MCFJ, den Boer E, Calasan B, et al. Personalized medicine of methotrexate therapy. Ned Tijdschr Klin Chem Labgeneesk. 2012;37:50-3.

16. Angelis-Stoforidis P, Vajda FJ, Christophidis N. Methotrexate polyglutamate levels in circulating erythrocytes and polymorphs correlate with clinical efficacy in rheumatoid arthritis. Clin Exp Rheumatol. 1999 May-Jun;17(3):313-20.

17. Dervieux T, Greenstein N, Kremer J. Pharmacogenomic and metabolic biomarkers in the folate pathway and their association with methotrexate effects during dosage escalation in rheumatoid arthritis. Arthritis Rheum. 2006 Oct;54(10):3095-103. doi: 10.1002/art.22129

18. Hobl EL, Jilma B, Erlacher L, et al. A short-chain methotrexate polyglutamate as outcome parameter in rheumatoid arthritis patients receiving methotrexate. Clin Exp Rheumatol. 2012;30:156-63.

19. Takahashi C, Kaneko Y, Okano Y, et al. Association of erythrocyte methotrexate-polyglutamate levels with the efficacy and hepatotoxicity of methotrexate in patients with rheumatoid arthritis: a 76-week prospective study. RMD Open. 2017;3:e000363 doi: 10.1136/rmdopen-2016-000363

20. Stamp L, O'Donnell J, Chapman P. Determinants of red blood cell methotrexate polyglutamate concentrations in rheumatoid arthritis patients receiving long-term methotrexate treatment. Arthritis Rheum. 2009 Aug;60(8):2248-56. doi: 10.1002/art.24653

21. Sandhu A, Dhir V, Bhatnagar A, et al. High methotrexate triglutamate level is an independent predictor of adverse effects in asian indian rheumatoid arthritis patients – A preliminary study. Ther Drug Monit. 2017 Apr;39(2):157-63. doi: 10.1097/FTD.0000000000000375