The following is a summary of “Posoleucel in Kidney Transplant Recipients with BK Viremia: Multicenter, Randomized, Double-Blind, Placebo-Controlled Phase 2 Trial,” published in the March 2024 issue of Nephrology by Chandraker et al.

Researchers conducted a retrospective study to evaluate the efficacy of Posoleucel, a multivirus-specific T-cell therapy, in treating BK virus infection among kidney transplant recipients. The aim was to mitigate the risks of BK virus-associated nephropathy, allograft rejection, and graft loss, with the added benefit of targeting five other opportunistic viruses.

They conducted a phase 2, double-blind study in which kidney transplant recipients with BK viremia were randomly assigned in a 1:1:1 ratio to receive posoleucel either weekly for 3 weeks followed by bi-weekly or monthly dosing or placebo for 12 weeks. Participants were then monitored for an additional 12 weeks post-treatment. The primary aim was to assess safety, while the secondary aim was to evaluate the plasma BK viral load reduction.

The results showed that 61 participants underwent randomization and dosing. Baseline characteristics were comparable across all groups. No deaths, graft-versus-host disease cases, or cytokine release syndrome incidents were reported. The percentage of patients experiencing adverse events judged by investigators as related to treatment was marginally lower in posoleucel recipients at 20% (4/20 patients) and 18% (4/22) for those receiving infusions bi-weekly and monthly, and 26% (5/19) in placebo recipients. No severe grade 3-4 adverse events or serious events in any group were attributed to treatment. No deaths, graft-versus-host disease cases, or cytokine release syndrome events were observed. Allograft rejection occurred in three participants, but investigators did not consider any treatment-related cases. In posoleucel recipients, a decrease in BK viremia was linked to an elevation in the circulating frequency of BK virus-specific T cells, with the presence and persistence of posoleucel confirmed through T cell receptor sequencing.

Investigators concluded that Posoleucel showed promise for reducing BK virus in kidney transplant recipients, but longer studies are needed to confirm its impact on long-term health.

Source: journals.lww.com/jasn/abstract/9900/posoleucel_in_kidney_transplant_recipients_with_bk.268.aspx