Redx slumps after it abandons trial of lead cancer drug
Dr Jane Robertson, Redx
Shares in Redx Pharma were under pressure today following the announcement that it would not be advancing its cancer drug candidate RXC004 into phase 3 testing in biliary tract cancer, after it failed to show efficacy in a proof-of-concept trial.
The first readout from its phase 2 programme for the porcupine inhibitor, in Wnt-ligand dependent BTC that had progressed after standard first-line care, missed the mark.
Data from 16 subjects with BTC enrolled into the PORCUPINE2 study showed “durable clinical benefit” in some patients and a good tolerability profile for RXC004, but Redx said that overall the results “are not sufficient to support the further development of RXC004 as a monotherapy in this treatment setting.”
It is not necessarily the end for RXC004, as phase 2 assessments in pancreatic cancer and colorectal cancer as a monotherrapy are ongoing, and Redx is also looking at the drug in combination with Merck & Co’s immune checkpoint inhibitor Keytruda (pembrolizumab) in Wnt-ligand dependent BTC and pancreatic cancer.
There’s no disguising that the initial results with RCX004 are a disappointment, however, and shares in Redx were down almost 16% this morning as investors digested the news.
The UK-based company’s chief medical officer, Dr Jane Robertson, said the results did not affect the working hypothesis that, when used in combination with checkpoint inhibitors, it may be able to overcome resistance mechanisms that reduce the activity of the immunotherapy.
“While today’s results do not support further clinical development of RXC004 as monotherapy in recurrent BTC, where very few drugs have received regulatory approval as single agents in this hard-to-treat disease, they are nonetheless consistent with the overall hypothesis that RXC004 has potential as an active component of combination therapy,” she said.
“We look forward to the data read out from the combination module with pembrolizumab that is expected in the second half of this year.”
BTC has an annual incidence of 51,000 patients and has an extremely poor prognosis, with only a 2% five-year survival rate and a treatment response rate of less than 5% with standard second-line chemotherapy, according to Redx.
The news comes shortly after Redx announced a merger with US biotech Jounce Therapeutics to create a biotech focused on cancer and fibrotic diseases. Once that goes through, the combined company’s pipeline will be led by RXC007, a selective ROCK2 inhibitor currently in a phase 2a trial in idiopathic pulmonary fibrosis (IPF).
