Transcenta has dosed the first subject in Phase IIa clinical trial of its antibody TST001 plus cisplatin and gemcitabine as a first-line therapy for individuals with systemic treatment-naïve locally advanced or metastatic biliary tract cancer in China.

The single-arm, open-label, multicentre trial will analyse the safety, tolerability and anti-tumour efficacy of TST001 in these patients.

TST001 is a humanised anti-Claudin18.2 monoclonal antibody with greater affinity.

It possesses improved antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) activities as well as potent anti-tumour activities in tumour xenograft models. 

Transcenta is claimed to be the first firm to analyse Claudin 18.2 targeting agent’s potential to treat biliary tract cancer.

Transcenta Global R&D head, executive vice-president and CMO Dr Michael Shi said: “Using our proprietary IHC antibody, Transcenta has shown that Claudin18.2 is over-expressed in the tumour of a subset of biliary tract cancer patients.

“As the combination of Claudin18.2 targeting agent with chemo backbone has shown promising activity in first line gastric cancer, the addition of TST001 to the first line chemotherapy regimen may also provide better treatment benefit to biliary tract cancer patients with Claudin18.2-expressing tumour.”

Previously, the US Food and Drug Administration granted Orphan Drug Designation to TST001 for treating people with gastric cancer or gastroesophageal junction (GC/GEJ).

Trials of TST001 are currently underway in the US and China.

A rare malignancy, biliary tract cancer comprises cholangiocarcinoma and gallbladder carcinoma.

In the initial stages of biliary tract cancer, radical resection is the standard and only treatment option.

Majority of the patients, however, are unable to undergo surgical resection because their tumour has progressed into the metastatic stage by the time they are diagnosed.

In April last year, the company announced plans for the Phase I trial of its bi-functional anti-PD-L1/TGF-β antibody, TST005, to treat various kinds of tumours.