Novel T-Cell Therapy May Show PFS Benefit in Stage IV Metastatic NSCLC

In the open-label, phase 1 Deltacel-01 trial, patients with stage IV NSCLC will receive 2 intravenous doses of KB-GDT-01 in combination with 4 courses of low-dose, localized radiotherapy over 10 days.

Treatment with the investigational, allogeneic, off-the-shelf Gamma Delta T-cell (GDT) therapy KB-GDT-01 (Deltacel™) may elicit a progression-free survival (PFS) benefit among patients with stage IV metastatic non–small cell lung cancer (NSCLC), according to interim results from part 1 of the phase 1 Deltacel-01 trial (NCT06069570).¹

Among 5 evaluable patients, the average PFS following treatment with KB-GDT-01 was 4.8 months, with outcomes ranging from 2 to 8 months.

Investigators reported no dose-limiting toxicities among patients who completed all doses of study treatment. One patient withdrew from the study before completing all doses due to an adverse effect (AE) associated with a pre-existing comorbidity; this toxicity was not related to KB-GDT-01, and the patient was not evaluated for PFS.

Developers anticipate early safety and tolerability findings from the Deltacel-01 trial in September. Additionally, further efficacy results are expected in October. Investigators are on track to launch part 2 of the trial in September.

“We are pleased to have completed enrollment in part 1 of our clinical trial,” Pietro Bersani, chief executive officer at Kiromic BioPharma, the developer of KB-GDT-01, said in the press release.¹ “The favorable results of our GDT therapy, particularly with respect to PFS, in the first two cohorts that comprise Part 1 underscore the potential of [KB-GDT-01] to treat solid tumors, and we look forward to launching part 2 of this study.”

Investigators designed KB-GDT-01 to exploit GDT-cell potency and target solid cancers. The agent contains unmodified gamma delta T cells derived from donors. Based on preclinical data from 2 studies, combining KB-GDT-01 with low-dose radiotherapy appeared to demonstrate favorable efficacy and safety.

In the open-label, phase 1 Deltacel-01 trial, patients with stage IV NSCLC will receive 2 intravenous doses of KB-GDT-01 in combination with 4 courses of low-dose, localized radiotherapy over 10 days. Patients will receive the investigational GDT therapy at 400 x 10⁶, 800 x 10⁶, or 1600 x 10⁶ cells plus radiation at 1.0 Gy per fraction.²

The trial’s primary end point will be AEs and dose-limiting toxicities. Secondary end points include objective response rate, PFS, overall survival, time to progression, time to treatment response, and disease control rate.

Patients 18 years and older with histologically or cytologically confirmed stage IV metastatic NSCLC, an ECOG performance status of 0 or 1, and disease progression on at least 2 lines of standard-of-care treatment including platinum-containing chemotherapy and immune checkpoint inhibitors are eligible for enrollment on the trial. Other requirements for study entry include having 1 or more measurable target lesions per RECIST v1.1 guidelines, and a minimum life expectancy of 6 months. Having adequate hematopoietic, hepatic, and renal function was another requirement for enrollment.

Those who have received chemotherapy, investigational, and/or checkpoint inhibitor therapy within 30 days of study entry are ineligible for enrollment on the trial. Patients are also excluded if they have active autoimmune disease requiring management with immunosuppressive therapy, infection requiring systemic treatment within 30 days of study entry, a history of peritoneal effusion, uncontrolled hypertension, human immunodeficiency virus, Hepatitis B, or Hepatitis C.

Investigators reported 6-month follow-up results for the first patient enrolled on the Deltacel-01 trial in June 2024.³ Scans at 6 months after initiating therapy showed a 13% reduction in the patient’s tumor size with KB-GDT-01; there were no new tumor lesions observed. These outcomes translated to a PFS of 6 months.

References

1. Kiromic BioPharma provides update on part 1 of the Deltacel-01 trial. News release. Kiromic BioPharma. August 9, 2024. Accessed August 12, 2024. https://tinyurl.com/22uavyxc
2. Safety study for a gamma delta T cell product used with low dose radiotherapy in patients with stage 4 metastatic NSCLC. ClinicalTrials.gov. Accessed August 12, 2024. https://tinyurl.com/49p25ckr
3. Kiromic BioPharma reports six-month results from first patient enrolled in Deltacel-01 clinical trial. News release. Kiromic BioPharma. June 6, 2024. Accessed August 12, 2024. https://tinyurl.com/28et29hk