Article Text

Download PDFPDF

LSO-083 ‘Systemic lupus erythematosus women with lupus nephritis in pregnancy therapeutic challenge (SWITCH)’: the systemic lupus international collaborating clinics experience
  1. Joo-Young (Esther) Lee1,
  2. Arielle Mendel1,
  3. Anca Askanase2,
  4. Sang-Cheol Bae3,
  5. Jill Buyon4,
  6. Ann E Clarke5,
  7. Nathalie Costedoat-Chalumeau6,
  8. Paul R Fortin7,
  9. Dafna Gladman8,
  10. Rosalind Ramsey-Goldman9,
  11. John G Hanly10,
  12. Murat Inanç11,
  13. David Isenberg12,
  14. Anselm Mak13,
  15. Marta Mosca14,
  16. Michelle Petri15,
  17. Anisur Rahman12,
  18. Jorge Sanchez-Guerrero16,
  19. Murray Urowitz17,
  20. Daniel Wallace18,
  21. Sasha Bernatsky1 and
  22. Évelyne Vinet1
  1. 1Department of Medicine, Division of Rheumatology, Research Institute of McGill University Health Centre, Canada
  2. 2Department of Medicine, Division of Rheumatology, Columbia University Lupus Center, USA
  3. 3Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Republic of Korea
  4. 4Department of Medicine, Division of Rheumatology, New York University Medical Center, USA
  5. 5Department of Medicine, Division of Rheumatology, Cumming School of Medicine, University of Calgary, Canada
  6. 6Department of Medicine, Centre de Reference Maladies Auto-immunes et Systemiques Rares, Hospital Cochin, France
  7. 7Department of Medicine, Division of Rheumatology, Centre ARThrite, Centre Hospitalier Universitaire de Québec, Université Laval, Canada
  8. 8Department of Medicine, University Health Network, Toronto Western Research Institute, University of Toronto, Canada
  9. 9Department of Medicine, Division of Rheumatology, Feinberg School of Medicine, Northwestern University, USA
  10. 10Department of Medicine, Division of Rheumatology, Queen Elizabeth II Health Sciences Center, Nova Scotia Rehabilitation Site, Dalhousie University, Canada
  11. 11Department of Internal Medicine, Division of Rheumatology, Istanbul University, Turkey
  12. 12Department of Rheumatology, University College London, UK
  13. 13Department of Medicine, Division of Rheumatology, Yoo Loo Lin School of Medicine, National University of Singapore, Singapore
  14. 14Department of Rheumatology and Immunology, University of Pisa, Italy
  15. 15Department of Medicine, Division of Rheumatology, Johns Hopkins University School of Medicine, USA
  16. 16Department of Medicine, Division of Rheumatology, Mount Sinai Hospital, University Health Network, University of Toronto, Canada
  17. 17Department of Medicine, Division of Rheumatology, Toronto Western Hospital, University of Toronto, Canada
  18. 18Department of Medicine, Division of Rheumatology, Cedars-Sinai Medical Centre, David Geffen School of Medicine Center at UCLA, USA


Background Many SLE patients develop lupus nephritis (LN) and receive mycophenolate mofetil (MMF), a teratogenic drug. Guidelines recommend azathioprine (AZA) in SLE pregnancy without providing guidance on pharmacogenetic testing and therapeutic monitoring although these may help personalize therapy (e.g., identifying ‘shunters’, non-adherence). We evaluated practice patterns pertaining to SLE women with LN in preconception and gestational periods, focusing on pharmacogenetic testing and drug monitoring.

Methods In 02/2022, we distributed an electronic survey to 39 Systemic Lupus International Collaborating Clinics (SLICC) members. Physicians were queried about number of LN patients seen for pregnancy planning, wait time physicians recommend preconception after renal response, choice of pregnancy-compatible immunosuppressive when switching from MMF, pharmacogenetic testing before AZA initiation, and therapeutic monitoring.

Results Response rate was 74%. On average, respondents saw 7.2 (standard deviation 6.6) LN patients in the preceding year for pre-pregnancy counselling. Most (93%) recommended waiting for a minimal time after achieving renal response on MMF before transitioning to a pregnancy-compatible immunosuppressive (19% suggested ≤ 6 months, 44% 6–11 months, 30% 12–23 months). In patients with inactive LN for ≥ 2 years, 86% switched immunosuppressives, while 14% discontinued MMF without switching. First choice of pregnancy-compatible immunosuppressive was AZA (90%). Tacrolimus (TAC) was preferred over cyclosporine (CsA) by 96% as second option. When initiating AZA, 38% never assessed thiopurine methyltransferase (TPMT) genotype and/or phenotype and 97% never tested for nudix hydrolase 15 (NUDT15) gene. When switching MMF to AZA preconception, 14% measured 6-mercaptopurine (6-MP) levels. Most (56%) faced barriers to 6-MP testing related to access, cost, and wait times. When patients were on TAC or CsA, 48% monitored drug each trimester, while 44% never did.

Conclusions There is low use of pharmacogenetic testing and therapeutic monitoring when transitioning MMF to a pregnancy-compatible drug preconception. We identified potential care gaps, which could be addressed by future pragmatic trials.

  • Therapeutic monitoring
  • Personalized management
  • Systemic lupus erythematosus pregnancy

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See:

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.