Redx Reports encouraging Zamaporvint (RXC004) Phase 2 combination data in MSS mCRC at ESMO GI Congress supporting genetic selection hypothesis in hard-to-treat GI Cancers

Zamaporvint in combination with anti-PD-1, in genetically-selected MSS mCRC patients led to partial responses being observed in ~30% patients, potentially higher than current SOC and in a setting where anti-PD-1 therapy alone is not effective

Data supports genetic selection of patients in hard-to-treat GI cancers

Alderley Park, UK, 28 June 2024 Redx Pharma (JPJ:REDX), the clinical-stage, small molecule biotechnology company,
announced data from all Phase 2 clinical trial modules of zamaporvint (RXC004), a potent, selective, orally-active Porcupine
inhibitor in development for Wnt-ligand dependent, hard-to-treat GI cancers at the European Society for Medical Oncology
Gastrointestinal Cancers (ESMO GI) Congress.

These data were from small, signal searching patient cohorts in the PORCUPINE study, investigating genetically-selected
patients (RNF43_mutant/RSPO-fusion subgroup) with microsatellite stable metastatic colorectal cancer (MSS mCRC) as
monotherapy and in combination with anti-PD-1 (NCT04907539); and the PORCUPINE2 study investigating all-comers
biliary tract cancer (BTC) as monotherapy and anti-PD-1 combination, as well as genetically-selected pancreatic cancer as
monotherapy (NCT04907851).

Natalie Cook, Chief Investigator for the zamaporvint Study Programme commented: "It is very encouraging to see the
data returned from this signal-searching study. The indications targeted are in populations with a particularly poor prognosis
and limited treatment options. Wnt inhibition has long held promise for this genetically-selected patient group and a tolerable, clinically active Porcupine inhibitor in combination with anti-PD-1 could potentially offer a new treatment option for patients with these particularly hard to treat cancers."

Dr. Helen Timmis, Interim Chief Medical Officer, Redx Pharma commented: "We are delighted to report the Phase 2 data
from our zamaporvint study programme which shows a disease control rate of 57% including partial responses in ~30% of the
patients treated with zamaporvint in combination with nivolumab in MSS mCRC. Real world evidence shows that the prognosis for the RNF43/RSPO mutant subgroup of MSS mCRC is significantly worse than in MSS mCRC patients without these Wnt aberrations, where outcomes are already poor. This early signal indicates that, in the right patient groups, the combination of Porcupine and immune checkpoint inhibition has the potential to provide a much-needed improvement on the current standard of care."

Read the full press release here