RS Oncology Data for Novel Treatment of Aggressive Cancers Selected for an Oral Presentation at ASCO Annual Meeting

– Data from phase 1 clinical trial of RSO-021 selected for the Developmental Therapeutics session on June 3rd, 2024

– Trial in progress for the ongoing expansion cohorts will be presented as a poster in the Lung Cancer session on June 3rd, 2024

CAMBRIDGE MA, May 1, 2024 – RS Oncology, a clinical-stage biopharmaceutical company focused on developing novel treatments for aggressive and rare cancers, today announced that it will present the complete Phase 1 dose escalation data as an oral presentation at the world’s largest oncology meeting, the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting.

The MITOPE phase 1 multicenter study, (clinical #NCT05278975) investigating the safety and tolerability of RSO-021, is a first-in-human trial. RSO-021 is a first-in-class therapy for treatment of mesothelioma and solid tumors in patients with malignant pleural effusion. Professor Dean Fennell from Leicester Hospitals Trust in the UK will present the complete dose escalation data as part of a rapid oral session and answer questions during a moderated panel discussion.

Aggressive cancers present tremendous challenges in treatment and management, primarily due to rapid growth and spread to other parts of the body. Malignant pleural effusion (MPE) develops as a direct extension of cancer into the pleural space and is associated with shorter life expectancies. Currently, the phase 2 expansion portion of MITOPE is underway in the UK, exploring RSO-021 as both a single agent and in combination therapy to treat stage IV metastatic cancers with MPE, including mesothelioma, lung, breast and ovarian cancers. Other causes of MPE include cancer that has spread from the stomach, kidney, ovaries, and colon. Dr. Sean Dulloo from University of Leicester will present an update of the MITOPE Phase 2 trial as a trial-in-progress poster presentation.

The data is embargoed until published by ASCO 5:00 PM (EDT) on Thursday, May 23, 2024.

Details of the Presentations

Rapid Oral Abstract

Title: First-in-human phase 1 clinical trial of RSO-021, a first-in-class covalent inhibitor of mitochondrial peroxiredoxin 3 (PRX3), in patients with malignant pleural effusion due to mesothelioma and other advanced solid tumors (MITOPE).

Presenter: Dean Fennell

Session Title: Developmental Therapeutics—Molecularly Targeted Agents and Tumor Biology

Day/Time: Monday June 3, 9:06 am (session from 8:00-9:30 am)

Abstract #3019

Poster Presentation

Title: Phase 2 study to evaluate the novel mitochondrial PRX3 inhibitor, RSO-021, as an intrapleural monotherapy and in combination with IV paclitaxel in patients with malignant pleural effusion due to mesothelioma or another advanced solid tumor.

Presenter: Sean Dulloo

Session Title: Lung Cancer—Non-Small Cell Local-Regional/Small Cell/Other Thoracic Cancers

Day/Time: Monday, June 3, from 1:30 – 4:30 PM CDT​​​​​​

Abstract: #TPS8124

Poster Bd: #381b

About RS Oncology

RS Oncology is a private, clinical-stage biopharmaceutical company leading scientific discoveries and global collaborations to improve the lives of patients with the aggressive cancers. Visit or follow us on LinkedIn and X.

Corporate Inquiries: Jarrett Duncan, CEO, RS