Rubius Therapeutics Reports Updated Clinical Data at AACR from the Ongoing Monotherapy Phase 1 Arm of the Phase 1/2 Clinical Trial of RTX-240 in Advanced Solid Tumors Demonstrating Single-Agent Activity and Favorable Tolerability
Best Responses Include Partial Responses in Certain Patients with Non-Small Cell
Expanding Ongoing Phase 1 Arm of RTX-240 + Pembrolizumab to Focus on Non-Small Cell
Management to Host Conference Call Today at
“Recent advances in immuno-oncology have transformed the treatment of cancer and improved outcomes for certain patients. Yet, of the estimated 40 percent of patients eligible for immunotherapy, the majority do not have durable responses. In addition, combinations of immune checkpoint inhibitors have higher toxicity, underscoring the need for safer and more effective immunotherapy combination treatments,” said
“We believe the encouraging results of monotherapy RTX-240 reported provide clinical support of the RED PLATFORM® and the development of our entire oncology pipeline of Red Cell Therapeutics given the programmable nature of our platform,” said
Updated Data from the Phase 1 Trial of RTX-240 in Patients with Advanced Solid Tumors
Nine dose cohorts (n=34) were completed in the monotherapy solid tumor arm of the trial at the time of the data cutoff on
As of the cutoff date, disease control was observed in 10 patients (1 partial response, 2 unconfirmed partial responses and 7 with stable disease), 9 of whom had experienced disease progression on prior anti-PD-1/anti-PD-L1 therapy.
There were three best responses of partial response (PR) in non-small cell lung cancer (NSCLC), anal cancer and uveal melanoma patients:
- An unconfirmed PR (uPR) with 41% decrease of all target lesions and a notable decrease of an external protruding chest wall mass in a patient with non-small cell lung cancer (NSCLC) whose disease had progressed on prior anti-PD-L1 therapy;
- A confirmed PR with a 54% reduction in the target lesions in a patient with metastatic anal cancer whose disease had progressed on anti-PD-L1 therapy; and
- An uPR with 100% decrease of the target hepatic lesion and resolution of multiple non-target hepatic lesions in a patient with metastatic uveal melanoma whose disease had progressed on anti-PD-1 therapy.
Stable disease was observed in 5 patients, including 3 with metastatic NSCLC and 2 with renal cell carcinoma (RCC) across the 3e10 cohorts, supporting the Company’s decision to expand the Phase 1 arm of RTX-240 plus pembrolizumab to NSCLC and RCC patients. One patient each with NSCLC and RCC remained on monotherapy treatment with SD greater than 6 months as of the cutoff date.
As of the cutoff date, RTX-240 has been shown to have been generally well tolerated with no treatment-related or investigator-identified immune-related Grade 3/4 adverse events (AEs) and no dose-limiting toxicities.
Based on the totality of clinical, tolerability and pharmacodynamic data, a recommended monotherapy Phase 2 dose of 5e10 cells administered every 3 weeks was selected. This dose will be further explored in the combination expansion cohort of NSCLC and RCC patients.
“Immune agonists and cytokines have been the focus of oncology research given their known importance for immune activation. However, current approaches have been unable to overcome toxicity challenges, resulting in a narrow therapeutic index, particularly in combination with checkpoint inhibitors. With today’s updated clinical data showing that RTX-240 generated clinical responses with favorable tolerability results in patients whose tumors had progressed on therapy with anti-PD-1/PD-L1 antibodies, we believe these data support the potential of immune agonists for the treatment of cancer,” said
Final Phase 1 Clinical Results in Relapsed/Refractory AML
Rubius also announced final clinical results from the Phase 1 arm of monotherapy RTX-240 in relapsed/refractory AML. As of the cutoff date of
“In this study, RTX-240 has shown activation and expansion of NK and T cells with favorable safety results, which continues to support the proposed mechanism of action of RTX-240. Based on these data, we believe RTX-240 could improve outcomes for AML patients when used as maintenance therapy for patients in remission following high-dose chemotherapy and stem cell transplantation,” continued
Upcoming Anticipated Milestones
To evaluate the full potential of RTX-240, Rubius’ other oncology programs and the RED PLATFORM, Rubius plans to execute several critical milestones within the next 12 months and has sufficient cash runway into the second half of 2023:
- Report initial Phase 1 clinical results for RTX-321 for the treatment of HPV 16-positive cancers during the second half of 2022;
- Report initial Phase 1 clinical results for RTX-240 in combination with pembrolizumab in advanced solid tumors and data from the additional NSCLC and RCC patients in the second half of 2022;
- Select a clinical candidate for the first autoimmune program in type 1 diabetes during the second half of 2022; and
- Report initial Phase 1 clinical results for RTX-224 for the treatment of advanced solid tumors during the first quarter of 2023.
AACR Poster Presentation
Abstract Title: Phase 1 Trial of RTX-240, Allogeneic Red Blood Cells Engineered to Express 4-1BBL and Trans-Presented IL-15, in Patients with Advanced Solid Tumors
Session Title: Phase I Clinical Trials 2
Session Date and Time:
Location:
Poster Board Number: 12
Abstract Number: CT187
Conference Call
The Company will host a conference call and webcast at
About RTX-240
RTX-240, Rubius Therapeutics’ lead oncology program, is an allogeneic, off-the-shelf cellular therapy product candidate that is engineered to simultaneously present hundreds of thousands of copies of the costimulatory molecule 4-1BB ligand (4-1BBL) and IL-15TP (trans-presentation of IL-15 on IL-15Rα) in their native forms. RTX-240 is designed to broadly stimulate the immune system by activating and expanding both NK and memory T cells to generate a potent anti-tumor response.
About the RTX-240 Clinical Trial
The Phase 1/2 clinical trial of RTX-240 is an open label, multicenter, multidose, first-in-human dose-escalation and expansion study designed to evaluate the safety and tolerability, pharmacokinetics, maximum tolerated dose, a recommended Phase 2 dose and dosing regimen of RTX-240. The trial is also assessing the pharmacodynamics of RTX- 240 measured by changes in T and NK cell number and function relative to baseline and anti-tumor activity. The trial has three separate Phase 1 arms: a monotherapy dose escalation arm in adults with relapsed/refractory or locally advanced solid tumors, a monotherapy dose escalation arm in adults with relapsed/refractory acute myeloid leukemia, and a combination therapy dose escalation arm with pembrolizumab in adults with relapsed/refractory or locally advanced solid tumors.
About
Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our expectations with respect to the potential of our pipeline of Red Cell Therapeutics, our plans to announce results from our RTX-240 trial in patients with solid tumors and AML and to share expected next steps for the Phase 2 clinical development, our expectations regarding our timelines for reporting additional clinical data, our expectations for and beliefs about the initial results from the RTX-240 trial and its validation of the RED PLATFORM and its impact on the potential of our entire oncology platform, and the extent to which the COVID-19 pandemic may impact Rubius’ ability to enroll patients in the trial will depend on future developments and our expectations regarding our strategy, business plans and focus. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this press release are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation, those risks and uncertainties related to the development of our Red Cell Therapeutic product candidates and their therapeutic potential, our ability to execute on our plans and expectations, our analyses of clinical and preclinical data and other risks identified in our filings with the
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Source: Rubius Therapeutics