Aprea Therapeutics, Inc. announced results of the primary data cut from its Phase 3 clinical trial evaluating the safety and efficacy of eprenetapopt with azacitidine (AZA) versus AZA alone in TP53 mutant myelodysplastic syndromes (MDS). The trial did not meet the predefined primary endpoint of complete remission (CR) rate. Analysis of the primary endpoint at this data cut demonstrated a higher CR rate in the experimental arm receiving eprenetapopt with AZA versus the control arm receiving AZA alone, but did not reach statistical significance. In the intention-to-treat population of 154 patients, the CR rate in the eprenetapopt with AZA arm was 33.3% (95% CI: 23.1% - 44.9%) compared to 22.4% (95% CI: 13.6% - 33.4%) in the AZA alone arm (P = 0.13). While analysis of certain secondary endpoints (ORR and duration of responses) appears to favor the experimental arm at this data cut, they are not significantly different. The median duration of overall survival at the primary data cut was similar between the arms. Additional patients in the study who have not achieved a CR remain on study treatment and the data will be analyzed at future pre-specified timepoints as set forth in the statistical analysis plan. The combination of eprenetapopt with AZA appeared well-tolerated, with an adverse event profile that was similar to the Company’s prior Phase 2 clinical trials. Subsequent analyses of the trial data, including secondary endpoints, will be conducted as the duration of patient follow-up increases. The Company expects to present the data at a future scientific conference. The Phase 3 trial enrolled 154 TP53 mutant MDS patients, randomized 1:1 to either the eprenetapopt with AZA arm or the AZA alone arm. Response criteria are those defined by International Working Group 2006 (IWG 2006) and include measures of peripheral blood counts and bone marrow blasts.