T-Cell Therapy Gets Orphan Drug Designation for AML

This content originally appeared on our sister site, OncLive.

The FDA has granted orphan drug designation to TC Biopharm's T-cell therapy TCB-002 (OmnImmune) for the potential treatment of relapsed/refractory acute myeloid leukemia (AML).¹

The decision was based off data from a phase 1a/2b trial (NCT03790072) that demonstrated the therapy's safety and tolerability in participants with AML.²

“This is another milestone achieved by TCBiopharm, further strengthening our leadership position in Gamma Delta therapies for oncology,” Bryan Kobel, chief executive officer, TC Biopharm PLC, stated in a press release¹. “The granting of orphan drug status provides us a 7-year window post approval of exclusive marketing rights for allogeneic gamma delta use in AML, another added layer of protection around our lead product in a commercial setting beyond our existing strong IP.”

Data came from 7 participants in the study were dosed with a low (n = 3) and high (n = 4) dose of the investigational allogeneic unmodified gamma delta T-cell product. All participants were given conditioning chemotherapy comprised of fludarabine at 25 mg/m2 from day -6 until day -2, and cyclophosphamide at 500 mg/m2 on days -6 and -5. Patients were dosed with TCB-002 on day 0.

One participant in the lowest-dose cohort achieved a morphologic leukemia-free state (MLFS) and 1 had stable disease described as a near complete response (CR). The last participant met all safety end points but was ultimately lost to follow-up due to a bilateral pneumonia comorbidity determined to be unrelated to study treatment.

Half the participants in the higher dose cohort acheived CRs. One patient had a significant reduction in cancer blast count at day 14 and another experienced disease progression.

Two patients who achieved a CR and stable disease were re-dosed with TCB-002. The patient with MLFS went on to receive 2 additional infusions of the agent. No adverse evenets (AEs) were observed following these infusions.

Participants were eligible for the trial if they relapsed after intensive chemotherapy or allogeneic hematopoietic cell transplant (HCT), experienced no response to at least 4 cycles of low-intensity therapy, had disease that was refractory to 2 cycles of induction therapy, or have experienced disease progression on low-intensity therapy with cytarabine, 5-azacitidine, or decitabine.

Participants had to be betwen 18 and 70 years of age, have more than 5% blasts in the bone marrow or peripheral blood, be candidates for lymphodepleting chemotherapy, a life expectancy of at least 3 months, and have a Karnofsky performance status of 50% or higher. Patients could not be candidates to receive high-dose salvage chemotherapy and/or allogeneic HCT.

Participants could not have uncontrolled infections, renal insufficiency, heart failure, respiratory insufficiency, significant liver impairment, received treatment with bisphosphonates, or had active autoimmune disease or graft-vs-host disease (GVHD).

The trial primarily assessed incidences of treatment-emergent AEs and dose-limiting toxicitites. Secondary outcomes included assessing CRs, overall survival, and quality of life.

Investigators also examined allogeneic gamma delta T-cell persistence in 2 treated patients. In a patient who received 3 infusions, the product continued to be detectable after 100 days. The second patient experienced hematological recovery and had sustained elevation in important immune cells more than 100 days following initial infusion.

The therapy was foudn to be well-tolerated by investigators and the Saefty Review Committee. No treated participants experienced GVHD, immune effector cell–associated neurotoxicity syndrome, or cytokine release syndrome.

“We look forward to the advancement of OmnImmune in the phase 2b/3 trial and to helping patients in AML in the near future,” Kobel added.

References

1. TC BioPharm announces FDA orphan drug status granted for OmnImmune. News release. TC BioPharm PLC; March 17, 2022. Accessed March 17, 2022. https://prn.to/3ttbelP

2. TC BioPharm announces positive phase 1b/2a data in late-stage acute myeloid leukemia patients treated with allogeneic gamma delta T cells. News release. TC Biopharm PLC; March 8, 2022. Accessed March 17, 2022. https://prn.to/3tjBGy5

3. Ex-vivo expanded γδ T-lymphocytes (OmnImmune) in patients with acute myeloid leukameia (AML). ClinicalTrials.gov. Updated March 30, 2021. Accessed March 17, 2022. https://clinicaltrials.gov/ct2/show/NCT03790072