Rather Than Directly Killing Tumors, CRG-150 Reprograms Immune Brake Cells and Enters Human Trials

Solid tumors have long been a difficult area for cell therapies to conquer. CoRegen’s CRG-150 has now received clearance from the U.S. Food and Drug Administration (FDA) for its investigational new drug application, allowing a Phase 1/2a first-in-human trial to begin. Rather than focusing on recognizing a specific tumor antigen, the therapy seeks to reprogram the immune “brakes” exploited by cancer, enabling the patient’s existing immune response to function again.

The trial is expected to enroll patients with metastatic triple-negative breast cancer, hormone receptor-positive/HER2-negative breast cancer, and metastatic prostate cancer. The study will first use dose escalation to assess safety, tolerability, and the cells’ behavior in the body, and to select a recommended Phase 2 dose; subsequent expansion cohorts will then further examine preliminary antitumor activity. CoRegen said it plans to begin enrollment in 2026, but has not yet disclosed the exact timing, number of participants, or list of trial sites.

CRG-150 targets regulatory T cells (Tregs). These cells normally suppress excessive immune responses and maintain self-tolerance, but they may also accumulate in the tumor microenvironment and suppress killer T cells and natural killer cells. According to information compiled by PackGene, the treatment involves isolating Tregs from a patient’s blood, using CRISPR to disrupt steroid receptor coactivator-3 (SRC-3) ex vivo, expanding the cells, and then infusing them back into the patient, making it an autologous cell therapy.

SRC-3 is a transcriptional coregulator involved in multiple gene-regulatory pathways. CoRegen maintains that intervening in SRC-3 within Tregs can weaken the immunosuppressive environment established by tumors and affect multiple immune checkpoint-related signals, including PD-1, PD-L1, CTLA-4, LAG-3, and CCR4. This differs from the approach of CAR-T cells, which directly track specific antigens: CRG-150 seeks to reconfigure the immune ecosystem surrounding tumors rather than build a standalone attack force that recognizes cancer cells.

Animal studies disclosed by the company showed that the modified Tregs could eliminate tumors in multiple mouse solid-tumor models and produced immune memory that resisted recurrence, with no signs of systemic autoimmunity observed. However, these results do not yet demonstrate efficacy in humans. Tregs themselves are important cells that prevent immune dysregulation, so the human trial will particularly need to clarify the persistence and distribution of the SRC-3-edited cells, as well as whether they cause inflammation or pose autoimmune risks.

Another difference that could affect the treatment burden is that patients are expected not to require lymphodepleting chemotherapy beforehand, as they do with many CAR-T regimens; this arrangement currently appears mainly in external reports and still needs to be confirmed in the formal trial protocol. Clinical manufacturing will be supported by Lonza. For an autologous, gene-edited cell product, factors ranging from cell isolation and editing efficiency to batch consistency could determine whether the therapy can progress from early-stage trials to larger-scale validation.

The FDA’s decision means that CRG-150 may begin clinical research; it does not amount to confirmation that the therapy is safe or effective, or to approval for marketing. The first question this trial must answer is also not whether it can transform solid-tumor treatment, but whether this strategy of reversing immunosuppression can achieve an acceptable safety range in humans and generate preliminary anticancer signals sufficient to support further research.