Announcement of Rogocekib Dose-Escalation Cohort Data Presentation at the 2026 European Hematology Association (EHA)

Chordia Therapeutics Inc. (headquartered in Fujisawa, Kanagawa Prefecture, Japan; CEO: Hiroshi Miyake) has announced data from the Phase 1/2 trial (CTX-712-CL-02) of rogocekib (CTX-712), a CLK inhibitor, in patients with relapsed or refractory acute myeloid leukemia (AML) and high-risk myelodysplastic syndromes (MDS). Rogocekib is a first-in-class oral small molecule that selectively inhibits CLK, a key regulator of RNA splicing, and is anticipated as a novel therapeutic option in myeloid malignancies where approved targeted therapies are limited. In this trial, rogocekib demonstrated a manageable safety profile similar to that observed in the Japanese Phase 1 trial, and preliminary anti-tumor activity as monotherapy was confirmed even in a more heavily pretreated patient population compared to the Japanese study.

Key Highlights

In the Phase 1/2 trial targeting patients with relapsed or refractory AML and high-risk MDS, rogocekib demonstrated a manageable safety profile.

Among the 34 evaluable patients, including lower-dose cohorts, enrolled in this trial—characterized by elderly patients with extensive prior treatment histories—rogocekib showed four objective responses as monotherapy (three CRi in AML, one mCR in MDS), despite the challenging patient background.

〇 Overall response rate (ORR) was 11.8% (4/34 patients), achieving four objective responses

〇 In subgroup analyses, the 100mg (once-weekly) AML cohort achieved a CRi rate of 50% (2/4 patients), and the 80mg (twice-weekly) AML cohort achieved a CRi rate of 20% (1/5 patients). In MDS, the 80mg (once-weekly) cohort achieved an mCR rate of 25% (1/4 patients).

〇 Among 14 patients with splicing mutations, 5 achieved more than 50% reduction in bone marrow blasts compared to baseline.

CTX-712-CL-02 Trial Overview

This trial (NCT05732103) is a multicenter, Phase 1/2 study conducted by the company in the United States, enrolling patients with relapsed or refractory AML and high-risk MDS. In the dose-escalation cohort, rogocekib tablets were administered once weekly at doses from 20mg to 140mg, or twice weekly from 60mg to 100mg, to evaluate safety, pharmacokinetics, pharmacodynamics, and preliminary efficacy.

Detailed Dose-Escalation Cohort Data

Among 42 enrolled patients, 23 (54.8%) had AML, 16 (38.1%) had MDS, and 3 (7.1%) had chronic myelomonocytic leukemia. Patients aged 65 or older accounted for 78.6%, and 57.1% had received three or more prior different therapies, indicating that more than half of the population consisted of elderly, heavily pretreated patients.

This trial utilized a new tablet formulation. Pharmacokinetic analyses showed no significant differences from results observed in Japanese patients.

Regarding safety, adverse events were observed in all patients, but a manageable safety profile was confirmed overall. The main adverse events were hematologic toxicities and gastrointestinal symptoms, with a toxicity profile dependent on dose and dosing schedule. These findings were largely consistent with those from Japanese patients.

In terms of efficacy, among the 34 evaluable patients in the dose-escalation cohort, the ORR was 11.8% (4/34 patients), with a CRi rate of 16.7% (3/18 patients) in AML and one mCR in MDS. Subgroup analyses showed a CRi rate of 50% (2/4 patients) in the 100mg (once-weekly) AML cohort and 20% (1/5 patients) in the 80mg (twice-weekly) AML cohort—aligning with efficacy signals observed in Japanese patients. Additionally, an mCR rate of 25% (1/4 patients) was observed in the 80mg (once-weekly) MDS cohort. While complete responses (CR) were not confirmed in this dose-escalation cohort, the company believes this may be due to the availability of multiple treatment options in the U.S., leading to longer treatment histories, and bone marrow exhaustion from accumulated prior therapies. These points were discussed at the investigator meeting in December 2025, and based on these insights, the protocol has been revised to better enroll patients with higher potential for efficacy, and expansion cohorts are currently ongoing.

These results indicate that rogocekib has a manageable safety profile and demonstrates anti-tumor activity as monotherapy in high-risk, relapsed/refractory hematologic malignancy patients. Notably, promising efficacy signals were observed in AML, and to the company’s knowledge, rogocekib is the only CLK inhibitor monotherapy demonstrating this level of efficacy. These findings support the clinical utility and future development potential of rogocekib as a novel therapeutic approach targeting RNA splicing regulation.

Dr. Guillermo Garcia-Manero, Interim Department Head of Leukemia at The University of Texas MD Anderson Cancer Center and principal investigator of the CTX-712-CL-02 trial, commented: "CLK is an important therapeutic target in leukemia. In this clinical trial involving patients with advanced MDS and AML, the safety of rogocekib was confirmed, and signals of clinical benefit were observed even in highly advanced patients. Further studies are warranted."

Future Development

Building on these results, the company will continue to evaluate the recommended Phase 2 dose and dosing schedule in expansion cohorts, incorporating the revised protocol to appropriately assess patient populations with higher expected efficacy. Further clinical development will be advanced for relapsed or refractory AML and high-risk MDS, aiming to maximize the value of rogocekib and establish it as a new treatment option addressing high unmet medical needs.

Hiroshi Miyake, CEO of Chordia Therapeutics, stated: "We are greatly encouraged that in this U.S.-based trial, rogocekib demonstrated anti-tumor activity as monotherapy in a challenging patient population of elderly individuals with extensive prior treatment histories. Based on these results, we will continue to evaluate the optimal dosing and schedule of rogocekib in expansion cohorts and strive to deliver new treatment options to patients who currently lack sufficient therapeutic choices."

Rogocekib (CTX-712) CLK Inhibitor Presentation Overview

Abstract Number

EHA-3974

Presentation Title

SAFETY, TOLERABILITY, AND PRELIMINARY ACTIVITY OF ROGOCEKIB IN PATIENTS WITH RELAPSED/REFRACTORY MYELOID MALIGNANCIES: RESULTS FROM A PHASE 1/2 STUDY (CTX-712-CL-02)

Presentation Format

Poster

Date and Time

June 13, 2026, 18:45–19:45 (CEST)

Presentation Abstract

SAFETY, TOLERABILITY, AND PRELIMINARY ACTIVITY OF ROGOCEKIB IN.