Nurix Therapeutics, Inc. (Nasdaq: NRIX) announced that the European Medicines Agency (EMA) has granted PRIME (PRIority MEdicines) designation to NX-5948 for the treatment of adult patients with relapsed or refractory chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL) after failure of both a BTK inhibitor and a BCL-2 inhibitor.
Significance of PRIME Designation
The EMA's PRIME initiative, launched in 2016, is designed to provide early and enhanced support to developers of promising medicines that target unmet medical needs. This designation aims to optimize development plans and accelerate the evaluation process, potentially bringing new therapies to patients more quickly. To be eligible for PRIME, medicines must demonstrate the potential to benefit patients based on early clinical data.
NX-5948: A Novel BTK Degrader
NX-5948 is an investigational, orally bioavailable, brain-penetrant, small molecule degrader of Bruton’s tyrosine kinase (BTK). It is designed to specifically eliminate BTK, a key growth signaling protein in B cells, through degradation via the ubiquitin proteasome system. This mechanism of action is particularly relevant for patients who have developed resistance to current BTK inhibitors.
Clinical Development and Early Data
NX-5948 is currently being evaluated in a Phase 1 clinical trial (NCT05131022) in patients with relapsed or refractory B-cell malignancies. Nurix has reported that NX-5948 demonstrates high potency against tumor cell lines resistant to current BTK inhibitors, which is a critical consideration for heavily pretreated CLL/SLL patient populations. Pivotal trials for NX-5948 are planned to begin in 2025.
Management Commentary
"PRIME designation for NX-5948 is an important recognition of the unmet patient need in CLL, particularly in the growing number of patients whose cancer has progressed following BTK inhibitor and BCL2 inhibitor therapy," said Arthur T. Sands, M.D., Ph.D., president and chief executive officer of Nurix. "This designation follows encouraging safety and efficacy data from our ongoing Phase 1 clinical trial, demonstrating early promise of clinical benefit as well as mechanistic data supporting the activity of NX-5948 independent of mutations that confer resistance to covalent and non-covalent BTK inhibitors."
