The FDA has granted clearance for a phase 2 trial evaluating leronlimab in patients with relapsed/refractory microsatellite stable colorectal cancer (CRC). CytoDyn, the biotechnology company developing leronlimab, finalized the study protocol after productive feedback sessions with the FDA. The trial, conducted in partnership with Syneos Health, is scheduled to begin enrolling patients in early 2025, following a kickoff meeting in late November 2024. This trial aims to address the unmet need for effective treatments in this challenging patient population.
The phase 2, open-label, multicenter study will randomly assign approximately 60 patients with CCR5-positive MSS mCRC to receive either 350 mg or 700 mg of leronlimab. Patients will be divided into 2 cohorts, with an initial safety lead-in group receiving the 350 mg dose before advancing to the higher dose group. Leronlimab will be administered weekly, while TAS-102 and bevacizumab will be given on a 3- or 4-week schedule within a 4-week cycle.
Combination Therapy Details
The trial will evaluate leronlimab in combination with trifluridine plus tipiracil (Lonsurf; TAS-102) and bevacizumab (Avastin) in patients with CCR5+, microsatellite stable (MSS), relapsed/refractory metastatic colorectal cancer (mCRC). This combination is specifically designed for patients whose tumors express CCR5 and who have progressed after multiple lines of treatment, including fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapies, as well as anti-VEGF and anti-EGFR therapies when appropriate.
Key eligibility criteria include measurable disease and prior exposure to standard mCRC therapies. CCR5 expression will be assessed through immunohistochemistry testing, and MSS status will be confirmed through IHC or next-generation sequencing.
Previous Oncology Data
Leronlimab has demonstrated potential in oncology, particularly in metastatic triple-negative breast cancer (mTNBC). A pooled analysis of 3 clinical trials presented at the 2022 American Society of Clinical Oncology Annual Meeting highlighted the possible benefits of leronlimab in mTNBC. Among 28 mTNBC patients treated with leronlimab at doses of 350 mg, 525 mg, or 700 mg, patients experienced a median progression-free survival (PFS) of 3.8 months and an overall survival (OS) of 6.6 months. In the subset of patients who received higher doses (525 mg or 700 mg), the median PFS extended to 6.1 months, with OS exceeding 12 months. Leronlimab was generally well tolerated, with few grade 3 treatment-emergent adverse events.
