Background and Importance According to the global recommendations for COVID-19 therapy, adult patients at risk of severe disease (including patients after organ transplantation) should be treated with antivirals: preferably nirmatrelvir/ritonavir (Paxlovid) or remdesivir (Veklury). Alternative choice is unlicensed use of molnupiravir (Lagevrio).

Aim and Objectives Our study focused on evaluating the effectiveness and safety of molnupiravir in patients with COVID-19 after successful kidney transplantation (KTx).

Material and Methods A cohort of 93 patients (62 males) was retrospectively evaluated, with 89.0% of patients having had a first KTx (the remainder having had a second KTx) and 39.0% with diabetes mellitus. The mean age of the patients at the time of molnupiravir therapy was 56 years (SD 12.9) and they received molnupiravir with mean of 2.24 days (SD 1.67) since confirmation of SARS-2-positivity. Immunosuppressive therapy was adjusted uniformly according to the site protocol and prednisone was increased for a maximum of two to three weeks. The safety of the proposed procedure concerning graft function and risk of rejection was evaluated based on the trend in creatininemia and urinary protein/creatinine index. Nonparametric Wilcoxon test was used.

Results The median serum creatinine value in the study population was 127 μmol/l (IQR 52) before COVID-19. Outpatient follow-up was within 1 month after quarantine with median 124 μmol/l post-disease creatinine (IQR 53,2). The difference in median creatinine values before and after molnupiravir therapy was not statistically significant (p = 0.8175). COVID-19 related hospitalisation occurred in 5.4% patients, one patient in the cohort died due to COVID-19 disease. Short-term discontinuation or modification of immunosuppression did not induce any rejection episode.

Conclusion and Relevance Our experience demonstrates that early initiation of molnupiravir may be an effective and safe therapy for COVID-19 disease in patients after kidney transplantation (where it is authorised in the Czech Republic until the end of 2023). Moreover, compared to Paxlovid, its use is not limited by drug-drug interactions and thus can be administered with calcineurin inhibitors.

References and/or Acknowledgements Supported by projects of the Ministry of Health of the Czech Republic – RVO; FNHK, 00179906 and the COOPERATIO programme, INDI scientific area and SVV 260 665.

Conflict of Interest No conflict of interest.