Protara cell therapy gets breakthrough, fast track tags for pediatric lymphatic malformations

The U.S. FDA has granted Protara Therapeutics’ investigational cell-based therapy, TARA-002, both breakthrough therapy and fast track designations for the treatment of pediatric patients with macrocystic and mixed cystic lymphatic malformations (LMs).

In addition, the FDA has selected TARA-002 to participate in the chemistry, manufacturing and controls development and readiness pilot (CDRP) program, which aims to support CMC development of products with expedited clinical development timeframes and provide patients with earlier access. The initiative is designed to promote earlier and more structured engagement between sponsors and the FDA on CMC development strategies. The agency began accepting requests from sponsors who wish to participate in year four of the CDRP in October 2025.

LMs are rare, congenital malformations of lymphatic vessels resulting in the failure of these structures to connect or drain into the venous system. Most LMs are present in the head and neck region and are diagnosed in early childhood during the period of active lymphatic growth, with more than 50% detected at birth and 90% diagnosed before the age of three years.

TARA-002 is an investigational cell therapy in development for the treatment of LMs aand non-muscle invasive bladder cancer (NMIBC). The therapy was developed from the same master cell bank of genetically distinct group A Streptococcus pyogenes as OK-432, a broad immunopotentiator marketed as Picibanil in Japan by Chugai Pharmaceutical.

In December 2024, Protara announced positive results from its ongoing phase 2 assessing intravesical TARA-002 in high-risk NMIBC in patients with carcinoma in situ or CIS who are Bacillus Calmette-Guérin (BCG)-unresponsive or BCG-naïve. TARA-002 elicited a 72% complete response rate across BCG exposures at six months and 70% at any time with 100% (9/9) of patients maintaining a complete response from three months to six months. In addition, two of three patients maintained a complete response at nine months.