Update on progress of planned resubmission of BLA of narsoplimab for stem cell transplant-associated thrombotic microangiopathy

In last week’s quarterly earnings release and associated call, Omeros stated that it was awaiting feedback from the  FDA on the company’s revised statistical analysis plan (“SAP”) for the BLA. Omeros has now received FDA’s response on the revised SAP, has no other pre-submission information requests pending and is not aware of any other impediment to resubmitting the narsoplimab BLA. Following data preparation, primary endpoint and other analyses will be conducted by an independent expert statistical group. If the analytical results support resubmission of the BLA, the company plans to finalize and resubmit the BLA as soon as possible.

As previously disclosed, as part of a September 2024 meeting with the FDA regarding Omeros’ proposed BLA resubmission, FDA provided minor feedback on the proposed SAP for the primary efficacy endpoint. The feedback was limited to requesting a few additional sensitivity analyses. Omeros accordingly revised and resubmitted the SAP and FDA has now responded with additional recommendations on the SAP, which are acceptable to Omeros. The independent statistical group will incorporate FDA’s additional recommendations into the final SAP, implement and validate all required modifications to the related statistical programs, and then conduct the prespecified efficacy analyses. Following validation of results, Omeros will share publicly the outcome of the primary analysis and, as completed, additional analyses.