Meeting With FDA Confirms Phase 3 Study of Soquelitinib in PTCL

An end-of-phase/pre-phase 3 meeting between the FDA and Corvus Pharmaceuticals, Inc. confirms plans to initiate a phase 3 registrational clinical trial of soquelitinib (formerly CPI-818) in relapsed peripheral T cell lymphoma (PTCL).¹

Soquelitinib is an interleukin-2-inducible T cell kinase (ITK) inhibitor that binds to ITK and modulates T cells. The investigational small molecule drug is given orally and has the potential to control differentiation of normal T helper cells and to enhance immune responses to tumors by augmenting the generation of cytotoxic killer T cells and the production of cytokines that inhibit cancer cell survival.

A registrational phase 3 trial is now anticipated to evaluate soquelitinib in patients with relapsed PTCL and plans to initiate in the first quarter of 2024.

“We are pleased with the outcome of our end-of-phase/pre-phase 3 meeting with FDA, allowing us to advance ITK inhibition with soquelitinib into a potentially registrational clinical trial for patients with relapsed peripheral T cell lymphoma,” said Richard A. Miller, co-founder, president, and chief executive officer of Corvus, in a press release. “We appreciate the FDA’s input and their confirmation on the key aspects of the trial design, including sample size, dosing, eligibility, comparator arm and endpoints. We are now focused on finalizing the study protocol, qualifying trial sites, and completing other standard steps required to initiate the trial. Based on current timelines, we anticipate that we can initiate the trial in the first quarter of 2024.”

Cancer t cells lymphocytes in human body © immimagery - stock.adobe.com

Preclinical data evaluating soquelitinib suggests that ITK inhibition can potentially treat a variety of solid and hematological cancers based on a novel immunotherapy mechanism of action.²

In prior research, soquelitinib has been able to prevent T-cell exhaustion, and optimal doses of soquelitinib have affected T-cell differentiation and induced the generation of Th1 helper cells. In addition, the agent has shown to block the development of both Th2 and Th17 cells and production of their secreted cytokines.

According to interim results from a phase 1/1b trial evaluating soquelitinib in patients with refractory T-cell lymphomas, the agent demonstrated tumor responses in very advanced, refractory, difficult to treat T-cell malignancies, including 1 complete response (CR), 1 nodal CR, and 2 partial responses among 11 evaluable patients treated at the optimal dose.³

Doses of soquelitinib up to 600 mg twice a day have been well-tolerated, and no dose-limiting toxicities were seen. Additionally, the study identified the dose that maximally affects T helper cell differentiation as 200 mg twice daily.

The phase 3 potentially registrational trial plans to enroll 150 patients with relapsed PTCL that have received up to 3 prior therapies. The study will randomize patients in a 1:1 fashion to receive soquelitinib 200 mg twice a day or standard-of-care chemotherapy.¹

The primary end point to be assessed is progression-free survival, with secondary end points of objective response rate and overall survival.

“Soquelitinib’s proposed mechanism of action, based on selective ITK inhibition, represents a platform opportunity with the potential to address a wide range of indications beyond hematologic cancers, including solid tumors and autoimmune/allergic diseases,” added Miller.

REFERENCES:

1. Corvus Pharmaceuticals confirms planned initiation of soquelitinib (CPI-818) phase 3 registrational clinical trial in peripheral T cell lymphoma following meeting with FDA. News release. Corvus Pharmaceuticals, Inc. September 6, 2023. Accessed September 11, 2023. https://tinyurl.com/bdcm5tx4

2. Pipeline. Corvus Pharmaceuticals, Inc. Accessed September 10, 2023 https://www.corvuspharma.com/our-science/our-pipeline/

3. Song Y, Ding N, Yoon DH, et al. ITK inhibitor induces dose-dependent Th1 skewing in normal T cells and is active in refractory T cell lymphomas. Presented at: 2022 ASH Annual Meeting; December 10-13, 2022; New Orleans, LA. Poster 3993.