New CAR T Therapy for ALL Earns FDA Orphan and Rare Pediatric Drug Designations

• The FDA has granted orphan drug designation (ODD) and rare pediatric disease designation (RPDD) statuses to UCART22 for the treatment of acute lymphoblastic leukemia (ALL).
• UCART22 is an allogeneic chimeric antigen receptor (CAR) T-cell therapy.
• The therapy is being investigated in the phase 1/2 BALLI-01 (NCT04150497) trial.

UCART22, an allogeneic CAR T cell therapy for ALL, has been granted ODD and RPDD by the FDA.¹

ODD is granted to agents that prevent, diagnose, or treat rare diseases or conditions. Drugs that have been granted ODD can be eligible for tax credits for qualified clinical trials, exemption from user fees, and a potential 7 years of market exclusivity.²

Similarly, the RPDD program incentivizes the development of drugs for rare pediatric diseases, and sponsors can be eligible for priority review vouchers.³

“We are excited that the FDA granted UCART22 both ODD and RPDD status in the treatment of acute lymphoblastic leukemia. This decision represents additional evidence of the potential of UCART22 to bring a much-needed therapeutic option to these patients with ALL. There is an urgent need to develop new therapies for ALL for patients who are not candidates for [hematopoietic stem cell transplant [HSCT] or relapse after CD19-directed CAR T-cell therapies and/or HSCT,” said Mark Frattini, MD, PhD, chief medical officer at Cellectis, in a press release.¹

About the BALLI-01 Trial of UCART22 in Patients with ALL

UCART22 is being investigated in the phase 1/2 BALLI-01 trial. Data were presented at the 2023 American Society of Hematology (ASH) Annual Meeting in December 2023 and showed a preliminary response rate of 67% at dose level 2 vs 50% at dose level 3. Updated data are expected by the end of the year.¹

The study’s primary end points are incidence of adverse events and occurrence of dose-limiting toxicities.⁴ Secondary end points include overall response rate, duration of response, progression-free survival, overall survival, and pharmacokinetics.

Following a lymphodepletion regimen, patients receive the CD22-targeting UCART22 with alemtuzumab (CLLS52), a CD52-targeting monoclonal antibody.

Patients aged 15 to 70 are eligible for enrollment in the study if they have B-cell ALL (B-ALL) blast cells expressing CD22, have been diagnosed with relapsed or refractory B-ALL, and have received at least 1 standard chemotherapy regimen and 1 salvage regimen. Those who have received cellular or gene therapy within 60 days of enrollment are not eligible for participation.

The study is enrolling across locations in California, Colorado, Illinois, Massachusetts, New York, Pennsylvania, Tennessee, Texas, and France and has an estimated completion date of January 31, 2026.

REFERENCES:

1. FDA grants orphan drug and rare pediatric disease designation status to Cellectis’ UCART22 product candidate for acute lymphoblastic leukemia (ALL) treatment. News release. Cellectis. July 25, 2024. Accessed July 26, 2024. https://tinyurl.com/bddextw8

2. Designating an orphan product: drugs and biological products. FDA. Updated July 8, 2022. Accessed July 26, 2024. https://tinyurl.com/24muw8am

3. Rare pediatric disease designation and priority review voucher programs. FDA. Updated May 28, 2024. Accessed July 26, 2024. https://tinyurl.com/yj6dxma7

4. Phase 1/​2 study of UCART22 in patients with relapsed or refractory CD22+ B-cell acute lymphoblastic leukemia (BALLI-01). ClinicalTrials.gov. Updated September 25, 2023. Accessed July 26, 2024. https://clinicaltrials.gov/study/NCT04150497