Pierre Fabre's Tabelecleucel Shows 47.7% Response Rate in Phase 3 Trial for Rare Post-Transplant Cancer
核心洞察
Pierre Fabre Pharmaceuticals (搜索) reported updated Phase 3 ALLELE study results showing tabelecleucel achieved a 47.7% objective response rate in patients with relapsed/refractory EBV+ PTLD (搜索) following transplant failure.
The allogeneic T-cell immunotherapy demonstrated consistent efficacy across both hematopoietic cell transplant and solid organ transplant patient populations, with median overall survival of 18.6 months in the HCT cohort.
A pediatric sub-analysis of 12 patients showed a 50% response rate with safety profiles consistent with the overall population, supporting potential treatment across age groups.
Pierre Fabre Pharmaceuticals (搜索) announced updated Phase 3 results for tabelecleucel at the American Society of Hematology Annual Meeting, demonstrating sustained efficacy in treating patients with relapsed/refractory Epstein-Barr virus positive post-transplant lymphoproliferative disease (搜索) (EBV+ PTLD (搜索)). The allogeneic T-cell immunotherapy achieved a 47.7% objective response rate across 86 patients in the ongoing ALLELE study, with consistent outcomes observed in both transplant populations.
Study Design and Patient Population
The ALLELE study is an ongoing multicenter, open-label Phase 3 trial that analyzed a cohort of 86 patients, including 29 hematopoietic cell transplant (HCT) patients and 57 solid organ transplant (SOT) patients. Patients received a median of two treatment cycles, with each cycle consisting of three infusions administered on days 1, 8, and 15, followed by imaging assessment on day 28.
"These two sub-analyses highlight the potential of tabelecleucel to improve outcomes for patients, both pediatric and adult, with R/R EBV+ PTLD (搜索) who after undergoing a potentially life-saving solid organ or hematopoietic cell transplant suddenly face yet another life-threatening illness," said Dr. Sarah Nikiforow, Assistant Professor of Stem Cell Transplantation at Dana-Farber Cancer Institute and study presenter.
Efficacy Results Across Patient Populations
The updated findings showed the HCT cohort achieved a 48.3% objective response rate, while the SOT cohort demonstrated a 47.4% response rate. Median overall survival from Kaplan-Meier estimates reached 18.6 months for the HCT cohort, while median overall survival for the SOT cohort was not estimable as more than half of patients remained in follow-up.
A sub-analysis examining treatment response by prior therapy in SOT patients revealed response rates of 52.4% for those who received rituximab and 44.4% for those who received rituximab plus chemotherapy.
Pediatric Population Shows Promising Results
A new analysis of 12 pediatric patients under 17 years of age demonstrated a 50% objective response rate, with complete responses reported in 4 patients and partial responses observed in 2 patients. The efficacy and safety profile in the pediatric subgroup remained consistent with the overall study population.
Six pediatric patients developed treatment-emergent adverse events, with 4 events in 2 patients considered treatment-related. Fatal serious adverse events occurred in 2 pediatric patients, though neither was considered related to treatment. No reports of tumor flare, infusion reactions, immune effector cell-associated neurotoxicity syndrome, graft versus host disease, transmission of infection, or transplant rejection were observed.
Safety Profile Remains Consistent
Safety findings aligned with previously published data across the study population. Serious adverse events were reported in 58.6% of HCT patients and 66.7% of SOT patients, with treatment-related events occurring in 1 HCT patient and 7 SOT patients. Fatal serious adverse events were reported in 5 HCT and 9 SOT patients, with none attributed to treatment by investigators.
One SOT patient experienced pyrexia, considered a potential sign of cytokine release syndrome possibly related to treatment. The updated data showed no reports of tumor flare, infusion reactions, immune effector cell-associated neurotoxicity syndrome, or transmission of infectious diseases. No graft versus host disease or organ rejection events were reported as tabelecleucel-related.
Regulatory Timeline and Unmet Medical Need
The FDA is currently reviewing tabelecleucel's biologics license application under priority review, with a target action date of January 10, 2026. The application seeks approval for tabelecleucel as monotherapy for adult and pediatric patients two years of age and older with EBV+ PTLD (搜索) who have received at least one prior therapy including an anti-CD20 (搜索) containing regimen.
"The updated data support the potential of tabelecleucel as an important advancement in addressing the significant unmet need for patients with EBV+ PTLD (搜索), who currently have no FDA-approved treatment options and may experience poor overall survival of only weeks to a few months following the failure of standard treatment," Dr. Nikiforow noted.
EBV+ PTLD (搜索) represents an ultra-rare, acute, and potentially deadly blood malignancy that occurs after transplantation when patient T-cell immune responses are compromised by immunosuppression. Poor median survival of 3 weeks and 4.1 months for HCT and SOT patients, respectively, is reported in EBV+ PTLD patients for whom standard of care failed.
Mechanism of Action and Development Program
Tabelecleucel is an allogeneic, off-the-shelf, EBV (搜索)-specific T-cell immunotherapy designed to selectively target and eliminate EBV-infected cells. Unlike autologous CAR-T therapies, the allogeneic T-cells are derived from third-party donors and are not genetically modified. T-cells are collected from healthy donor blood and activated through exposure to Epstein-Barr virus (搜索) antigens, enriching for T-cells that recognize EBV before expansion, characterization, and cryopreservation.
The biologics license application is supported by pivotal ALLELE study data and supportive evidence covering more than 430 patients treated with tabelecleucel. Adriana Herrera, Chief Executive Officer of Pierre Fabre Pharmaceuticals (搜索) Inc., emphasized the therapy's potential impact: "These patients have undergone a difficult journey to receive a life-saving transplant only to be diagnosed with this ultra rare form of cancer and they deserve an effective treatment option following failure of standard-of-care therapy."