RRx-001 + Irinotecan Significantly Improved Progression Free Survival (PFS) Versus Regorafenib in the Randomized Phase 2 ROCKET Trial in Advanced Colorectal Cancer

Dec 14, 2022

Results from the ROCKET trial, published in the journal Clinical Colorectal Cancer, demonstrate the potential chemoprotective effects of RRx-001

San Diego, Calif., Dec. 14, 2022 – EpicentRx Inc. (“EpicentRx”), a leading-edge, clinical stage biopharmaceutical company that uses groundbreaking science to treat cancer and inflammatory-driven diseases, announced today the publication of a randomized, Phase 2 trial which demonstrated a statistically significant and clinically meaningful progression-free survival (PFS) benefit for the small molecule NLRP3 inhibitor, RRx-001, plus irinotecan versus standard of care regorafenib in patients with advanced colorectal cancer. The trial, ROCKET, included patients with third- or fourth-line colorectal cancer that previously received the irinotecan-containing chemotherapy regimen, FOLFIRI.

The ROCKET data was published in the December 2022 issue of the journal Clinical Colorectal Cancer.

Regorafenib, a poorly tolerated multi-kinase inhibitor, was FDA-approved in third- or fourth-line colorectal cancer based on a Phase 3 study, which demonstrated a 6.4-month overall survival and a 1.9-month progression free survival.[1]

In the ROCKET trial, 34 patients were randomized 2:1 to receive a priming dose of RRx-001 4 mg IV weekly for two months followed by irinotecan, a chemotherapy agent, associated with a 40% rate of severe diarrhea, which they had previously received and failed, at a dose of 180 mg per meter squared given every two weeks until progression versus regorafenib 160 mg given by mouth, three weeks on/one week off until progression.

The median overall survival was 8.6 months for RRx-001 plus irinotecan and 4.7 months for regorafenib. Median progression free survival was 6.1 months for RRx-001 plus irinotecan vs. 1.7 months for regorafenib, a statistically significant result (two-sided log-rank test, p = 0.0030). Overall response rate was 20.8% for RRx-001 plus irinotecan vs. no response for regorafenib. Moreover, the toxicity profile of RRx-001 plus irinotecan was substantially improved compared with regorafenib. Also, there were no observed cases of severe diarrhea with irinotecan, likely due to protection of the gastrointestinal (GI) tract from RRx-001. Reduction or prevention of side effects from chemotherapy, like severe diarrhea, leads to less dose delays or dose reductions and consequently improves antitumor outcomes.

The prognosis for patients with CRC has historically been poor in later lines of therapy with response rates of approximately 1-2% and median PFS of approximately two months. [2]

According to EpicentRx CEO and practicing gastrointestinal oncologist, Dr. Tony Reid MD, PhD, “Granted, ROCKET was a small trial; however, as a GI oncologist, treatment with regorafenib is commonly associated with significant skin irritation and fatigue, among other symptoms.  I think oncologists would welcome a better-tolerated, more active alternative for colorectal cancer patients that have progressed on front-line therapy. Hence, these results from ROCKET, if confirmed in a Phase 3 trial, would likely lead to additional options for third line colorectal cancer and beyond treatment.”

About RRx-001
RRx-001 is a highly selective NLRP3 inhibitor with vascular normalization and tumor associated macrophage polarization properties that resensitizes tumors to previously administered therapies. RRx-001 is under investigation in a Phase 3 trial for the treatment of small cell lung cancer (SCLC), and in a Phase 2 trial for protection against oral mucositis in first line head and neck cancer. It is also under development as a medical countermeasure for nuclear and radiological emergencies and as a treatment for neurodegenerative diseases like Parkinson’s and ALS/MND. For more information visit www.epicentrx.com.

About EpicentRx, Inc.
EpicentRx is a leading-edge clinical-stage biopharmaceutical company with a complementary pipeline of small molecules, novel drug delivery devices, and cancer selective virus platforms that target inflammatory diseases of significant unmet need.


[1] Grothey A, Van Cutsem E, Sobrero A, et al. Regorafenib monotherapy for previously treated metastatic colorectal cancer (CORRECT): an international, multicentre, randomised, placebo-controlled, phase 3 trial. Lancet. 2013;381:303–312.

[2] Grothey A, Van Cutsem E, Sobrero A, et al. Regorafenib monotherapy for previously treated metastatic colorectal cancer (CORRECT): an international, multicentre, randomised, placebo-controlled, phase 3 trial. Lancet. 2013;381:303–312.