Corvus Pharmaceuticals, Inc. announced new interim data from its Phase 1/1b clinical trial of soquelitinib in patients with relapsed PTCL. Soquelitinib demonstrated durable anti-tumor activity, evidenced by progression free survival, duration of response and overall survival rates that exceed current standard of care therapies for patients with relapsed PTCL. The data continues to support the advancement of soquelitinib into a Phase 3 registrational clinical trial in PTCL.

New Soquelitinib Interim Data from the Phase 1/1b Clinical Trial: Updated interim data as of November 27, 2023: A total of 36 patients were enrolled in the Phase 1/1b trial at the optimum 200 mg two-times a day dose, including 21 evaluable patients who would be eligible in the planned registrational Phase 3 clinical trial based on =1 and =3 prior therapies (eligible patient population) and 11 evaluable in the corresponding ineligible population based on ?3 prior therapies (ineligible patient population). In the Phase 1/1b clinical trial, the median number of prior therapies was 2 for the eligible patient population and 6 for the ineligible patient population. The rationale for enrolling these patient populations and the stratification analysis was to confirm the eligibility requirements planned for the company's Phase 3 clinical trial.

For the eligible patient population, objective responses (complete response, CR plus partial response, PR) were seen in 7 of 21 patients with disease control (CR, PR and stable disease) in 12 of 21 patients. The stable disease group included 5 patients who achieved tumor reductions that did not meet the criteria for a PR, with two of these patients continuing on therapy. For the eligible patient population, the median duration of response (DOR) for the seven patients with objective response by Lugano criteria was 14.5+ months (ranged from 6.9-25.2 months); three of these patients continued on therapy.

A total of five patients in the eligible patient population remained on therapy, including one patient with a CR at 21+ months, two patients with a PR at 3+ and 8+ months, and 2 with stable disease at 3+ and 5+ months. Kaplan Meier estimated median progression free survival was 6 months for the eligible patient population. Kaplan Meier estimated overall survival at 2 years was 77% for all 36 patients.

One additional eligible patient, not shown here, was treated at a higher dose and achieved a PR. While in PR, this patient went on to receive a bone marrow transplant and achieved a CR, which has continued as of the data cutoff without any further therapy for 2+ years. For the ineligible patient population, no objective responses were seen in 11 evaluable patients.

Molecular Studies on Patient Tumors Support Soquelitinib?s Novel Mechanism of Action Additional new interim data from the Phase 1/1b clinical trial of soquelitinib will be presented December 9, 2023 Ning Ding, Ph.D. from Peking University Cancer Hospital & Institute in Beijing, China, in a poster session (abstract #1442) at the 65th American Society of Hematology (ASH) Annual Meeting & Exposition, which is taking place in-person and virtually from December 9-12, 2023. The poster reports on the evaluation of blood samples and tumor biopsies from eight patients who participated in the trial, taken at baseline and during treatment (one patient was sampled during stable disease and again during response, and therefore was counted twice as reflected in the data below). The results support soquelitinib?s novel mechanism of action, and demonstrated increases in cytotoxic killer T cells and reductions in markers of T cell exhaustion: Responding patients (N=2) showed a sustained increase in CD4+ Th1 cells in the blood and an increase in CD8+ TEMRA cells (T effector memory cells).

TEMRA cells are T cells that have responded to an antigen and are able to mediate effector functions, such as the destruction of tumor cells; Patients with stable disease (N=4) showed increases in these cell populations that were transient; Patients who progress (N=3) showed no increase in these cells; Single cell RNA sequencing of tumor biopsies showed soquelitinib treatment increased expression of cytolytic effector molecules and led to a reduction of T cell exhaustion markers.