ContraFect Corporation announced the database lock of its Phase 3 DISRUPT (Direct Lysis of Staph aureus Resistant Pathogen Trial) study of exebacase in patients with Staph aureus bacteremia, and a summary of the topline data and the preliminary findings from its own analysis of data from the interim futility analysis (the Futility Dataset). All patients in the DISRUPT study have now been independently adjudicated and the study database has been locked. The blinding and data integrity of the study was maintained throughout, enabling the company to not only share the Futility Dataset, but also to utilize the results of the study, including the safety data, in future regulatory filings for exebacase.

The interim futility analysis was conducted, as planned, when approximately 60% of the primary endpoint population, patients with methicillin-resistant S. aureus (MRSA) bacteremia, had been randomized and followed for 14 days after treatment. The results below from the Futility Dataset and the company's own analysis were generated based on the clinical response of the primary endpoint, at day 14 in 84 MRSA bacteremia patients, of which 55 patients were treated with exebacase plus standard of care (SOC) antibiotics (the Exebacase Arm) and 29 patients were treated with placebo plus SOC antibiotics (the SoCA Arm). Clinical response at day 14 was 52.7% in the Exebacase Arm (n=55) compared to 58.6% in the SoCA Arm (n=29).

The two arms were well balanced in most baseline factors including final diagnosis, primary source of infection, risk factors for bacteremia, SOC antibiotic used and age. There was an imbalance in the baseline disease severity of patients, as determined by the APACHE II score, with 34.8% of patients in the Exebacase Arm having an APACHE II score >15 at randomization, as compared to only 13.8% of patients in the SoCA Arm. A patient with an APACHE II score above 15 is considered to have an extremely poor prognosis and a significantly increased risk of mortality.

Subgroup analyses of clinical response were all as expected, based on the topline results, other than APACHE II subgroups. Proper study randomization and drug allocation was confirmed by pharmacokinetic data. The Phase 3 DISRUPT study of exebacase is a randomized, double-blind, placebo-controlled clinical study conducted in the United States in 259 of the planned 348 patients with S. aureus bacteremia, including right-sided endocarditis.

Enrollment in the trial was stopped following a review of the pre-specified, interim futility analysis by the independent Data Safety Monitoring Board (DSMB). The DSMB recommended the trial be stopped because the conditional power of the trial was below the pre-specified threshold for futility as per the DSMB charter. No safety concerns were noted by the DSMB.

All patients have completed all study visits, and all patient outcomes have been verified by the blinded adjudication committee. The full results and the clinical study report are expected in the first quarter of 2023. The company is planning a virtual fireside chat in the first quarter of 2023 for an in-depth review and discussion of the DISRUPT study.