WASHINGTON — Results from the ATHENA trial presented at ASN Kidney Week suggested azathioprine conferred similar outcomes as mycophenolate mofetil for kidney transplant recipients. Azathioprine was also less expensive which, according to the researchers, makes the drug a worthy alternative for patients who are also on low-dose cyclosporine immunosuppression.
Paolo Cravedi, MD, PhD, of Icahn School of Medicine at Mount Sinai in New York, told attendees at a press conference that the study followed two large trials from the 1990s that found mycophenolate mofetil was associated with a significant reduction in acute cellular rejection compared to azathioprine in kidney transplant recipients. He said that, as a result of these trials, mycophenolate mofetil replaced azathioprine worldwide which had a major economic impact.
“Something that should be kept in mind,” he said, “is that an old formulation of cyclosporine was still being used when these trials were done. When we compared the drugs with the new formulation, we couldn’t find any benefit of mycophenolate mofetil over azathioprine. They were virtually identical in terms of patient survival and graft survival.”
As these results were found using standard levels of immunosuppressive agents, Cravedi said the ATHENA trial was designed to test the safety and efficacy of azathioprine compared to mycophenolate mofetil with today’s minimized doses of immunosuppression.
Therefore, researchers included 119 patients on mycophenolate mofetil and 114 patients on azathioprine in their study. At 3 years, they found 31.9% of those taking mycophenolate mofetil developed chronic allograft nephropathy vs. 32.4% taking azathioprine. Similar results were also seen between the two groups regarding biopsy-proven acute cellular rejection (18.5% on mycophenolate mofetil vs. 21.1% on azathioprine), subclinical acute cellular rejection (9.2% vs. 7%) and graft failure (5% vs. 6.1%). eGFR measured at 3 years was 53.8 mL/min/1.73m2 for those on mycophenolate mofetil vs. 51.4 mL/min/1.73m2 with azathioprine.
Cravedi said that while both drugs demonstrated nearly identical safety profiles, azathioprine was significantly less expensive than mycophenolate mofetil.
“Our cost analysis showed that putting a kidney transplant recipient on azathioprine instead of mycophenolate mofetil would save $3,500 over 1 year of treatment,” he said. “Due to the lower cost of azathioprine, we think it represents a valuable alternative to mycophenolate mofetil in patients who are also on low-dose immunosuppression.” – by Melissa J. Webb
Cravedi P, et al. Abstract FR-OR135. Presented at: ASN Kidney Week; Nov. 7-10, 2019; Washington, D.C.
Disclosure: Cravedi reports no relevant financial disclosures.