Cellenkos is advancing its pipeline of cell-based immunotherapies following FDA clearance of an investigational new drug application for CK0802.

The agency’s clearance enables the initiation of a mid-stage clinical trial in steroid-refractory graft-versus-host disease (GVHD), a setting with limited treatment options and poor survival outcomes.¹

What are the next steps?

On the heels of FDA’s clearance, the company plans to begin a Phase Ib/IIa trial evaluating CK0802 in patients who have failed to respond to systemic corticosteroids following allogeneic stem cell transplantation.¹ The study, expected to start in the second half of 2026, will assess safety, tolerability, and early efficacy, with overall response rate at Day 29 serving as the primary endpoint. Initial data readout is anticipated in early 2027.

Steroid-refractory GVHD remains a significant unmet need in post-transplant care. While allogeneic stem cell transplantation can be curative for certain hematologic malignancies, up to half of patients develop GVHD, in which donor immune cells attack healthy tissues.¹

Standard first-line treatment with high-dose steroids is effective in only about 50% of cases, and subsequent options are often limited by toxicity and lack of durable responses. Two-year survival rates for steroid-refractory patients remain around 30%, underscoring the need for new therapeutic approaches.

“FDA clearance to advance CK0802 into a Phase 1b/ 2a trial marks a hopeful step forward for patients facing the dire prognosis of steroid-refractory GVHD,” said Simrit Parmar, MD, MSCI, founder of Cellenkos. “CK0802 is uniquely qualified to function under intense inflammatory stress, resetting the patient's immune system, and de-escalating donor T-cell attack without the toxicities typically associated with broad-spectrum immunosuppression.”

What is CK0802?

CK0802 is an allogeneic, off-the-shelf regulatory T cell (Treg) therapy derived from cord blood.¹ Unlike traditional immunosuppressive treatments, which broadly dampen immune activity, Treg therapies are designed to restore immune balance by selectively suppressing pathological immune responses. The therapy is engineered to remain functional in highly inflammatory environments and to home to affected tissues, where it can modulate immune activity.

Mechanistically, CK0802 is designed to address multiple drivers of GVHD. The cells release anti-inflammatory cytokines such as IL-10 to inhibit pro-inflammatory signaling, act as “cytokine sinks” to reduce availability of IL-2 required for pathogenic T cell survival, and target antigen-presenting cells that amplify immune activation.¹ The approach also aims to induce longer-term immune tolerance by reprogramming the patient’s endogenous immune system.

“Clearance of our IND application is a major milestone for Cellenkos and confirms that the FDA is satisfied with the clinical, preclinical and manufacturing data submitted in support of CK0802, further validating our Crane manufacturing platform,” said Tara Sadeghi, chief operating officer of Cellenkos. “This trial will provide critical data to guide the design of future, pivotal studies.”

Why is FDA’s clearance of CK0802’s application important?

CK0802’s off-the-shelf design may offer logistical advantages compared to autologous cell therapies, particularly in acute settings where rapid intervention is required. CK0802 can be administered without the need for HLA matching and has a shelf life of up to three years, which could support broader accessibility if clinical efficacy is confirmed.

Earlier clinical data from a randomized, placebo-controlled study in severe Covid-19 acute respiratory distress syndrome suggested potential activity in controlling hyperinflammatory states, with high probabilities of improved survival and recovery outcomes. While these findings are from a different indication, they provide preliminary support for the platform’s ability to modulate immune-driven pathology.²

Sources

1. Cellenkos Announces FDA Clearance of Investigational New Drug (IND) Application for Phase 1b/ 2a Trial of CK0802 in Steroid-Refractory Graft-versus-Host Disease (GVHD) Cellenkos Inc. May 5, 2026 https://www.prnewswire.com/in/news-releases/cellenkos-announces-fda-clearance-of-investigational-new-drug-ind-application-for-phase-1b-2a-trial-of-ck0802-in-steroid-refractory-graft-versus-host-disease-gvhd-302761869.html
2. A Study to Evaluate the Safety and Pharmacokinetics of OC-001 in Patients With Locally Advanced or Metastatic Cancers National Library of Medicine January 12, 2026 https://clinicaltrials.gov/study/NCT04260802