FDA Lifts Clinical Hold on Atara's EBVALLO Epstein-Barr T-cell Programme

The FDA lifted the clinical hold on Atara Biotherapeutics' EBVALLO (tabelecleucel) development programme on May 5, 20251
This decision allows Atara to resume clinical trials for the T-cell immunotherapy product2
The clinical hold was initially placed in January 2025 due to GMP compliance issues identified at a third-party manufacturing facility14
Atara can now restart enrollment in the Phase III ALLELE study of EBVALLO for treating Epstein-Barr Virus-associated post-transplant conditions2
The FDA has granted a Type A Meeting to discuss the path forward for the Biologics License Application (BLA)1
EBVALLO is an allogeneic T-cell immunotherapy targeting Epstein-Barr virus (EBV)1

## Background Information:

Atara Biotherapeutics is developing EBVALLO as part of its novel allogeneic Epstein-Barr virus T-cell platform aimed at creating transformative therapies for patients with cancer and autoimmune diseases1. The FDA previously accepted a biologics license application (BLA) for tabelecleucel as a treatment for EBV-positive PTLD in July 20245.

The clinical hold was directly linked to GMP compliance issues identified during the pre-license inspection of a third-party manufacturing facility, which was referenced in a Complete Response Letter (CRL) issued on January 16, 202514.

## Clinical Progress:

The Phase III ALLELE trial (NCT03394365) has shown promising results, with tabelecleucel producing an objective response rate of 50.7% across the overall population. The median duration of response was 23 months, and the median overall survival was 18.4 months5.

Atara is working closely with its partner Pierre Fabre Laboratories and clinical trial sites to resume enrollment and treatment of patients as soon as possible1. The company's president and CEO, Cokey Nguyen, emphasized that patient safety remains their priority while maintaining high standards for their programs5.

Sources:

1. https://investors.atarabio.com/news-events/press-releases/detail/371/atara-biotherapeutics-provides-regulatory-updates-on

2. https://firstwordpharma.com/story/5956749

4. https://www.cgtlive.com/view/all-atara-biotherapeutics-t-cell-immunotherapy-trials-placed-clinical-hold-fda

5. https://www.cancernetwork.com/view/fda-puts-clinical-hold-on-tabelecleucel-in-ebv-ptld-ata3219-in-lymphoma