Intravesical Paclitaxel for the treatment of Upper Tract Urothelial Carcinoma ("UTUC")

UTUC is estimated to have a prevalence of 45,000 patients in the United States with four times higher prevalence rates in some Asian countries. There are currently no drugs approved for the treatment of UTUC, and the complexity of the upper urothelial tract presents significant challenges to reaching and surgically resecting all tumors.

TSD-005 as based on a similar formulation as TSD-001 and once initial TSD-001 Phase 1/2a studies have been completed,  it will enter its own Phase 2 trials.

It is likely that TSD-005 will receive Orphan Drug Designation for the treatment of UTUC in the United States and the European Union. Such designation will make TSD-005 eligible for seven years of exclusivity from approval in the United States, and ten years of exclusivity in the European Union.

Typically, patients with high or low grade UTUC exhibiting multiple tumors undergo kidney and upper urothelial tract removal (nephroureterectomy). If approved, TSD-005 could be the first formulated and approved treatment for UTUC that could provide an welcome alternative to these patients.

Orphan disease

UTUC is an uncommon disease with a prognosis worse than that of primary urothelial carcinoma of the bladder. It refers to malignant changes of the transitional urothelial cells lining the upper urothelial tract of the renal pelvis and ureter. UTUC typically exhibits high local recurrence and development of metastases in about 60% of all cases. Similar to NMIBC, the prognosis of patients with UTUC greatly depends on whether the tumor is in the muscle-invasive or non-muscle invasive stage at the time of diagnosis. Non-muscle invasive UTUC occurs roughly 40% of the time and is divided into two grades, low and high. Low grade typically represents 75% to 87% of patients diagnosed with non-muscle invasive UTUC.

UTUC accounts for approximately 5% to 10% of all new cases of urothelial cancer, which corresponds to an estimated annual incidence in the United States of up to 7,500 cases. The incidence rate in China is about four times higher than most Western countries. In 2012, the estimated prevalence of UTUC in the United States was approximately 45,000, of which approximately 14,500 had low-grade disease. UTUC is nearly three times more common in men than women and affects mostly the elderly.

Due to the small patient population, it is a considered an orphan disease in the USA.

Lack of effective treatments

There are currently no drugs approved by the FDA for the treatment of UTUC, representing a significant unmet medical need. Moreover, the complexity of the upper urothelial tract presents significant challenges to the proper identification and ability to reach and surgically resect all tumors.