AMBIGUOUS RESULTS

Curis's emavusertib shows responses in BTKi-resistant brain lymphoma, no ORR given

Updated TakeAim Lymphoma data covered 46 PCNSL patients and reported objective responses in BTK-inhibitor-experienced cases, but Curis withheld a numeric response rate or formal endpoint result.

Curis disclosed updated TakeAim Lymphoma data on 46 relapsed/refractory PCNSL patients, including 7 BTK-naive and 39 BTKi-experienced cases, and reported objective responses in the BTKi-experienced group without a numeric ORR.

By AppliedXLJuly 22, 2026Trial NCT03328078

Executive Summary

Curis disclosed updated data from its Phase 1/2 TakeAim Lymphoma study in relapsed or refractory primary CNS lymphoma, reporting objective responses in patients who had already progressed on a BTK inhibitor, a population it says otherwise lacks approved options.
The company described the result qualitatively rather than with a formal response rate, confidence interval, or durability figure, so the clinical magnitude of the claimed benefit cannot yet be sized.
The update landed well after the window the company had originally guided, following a trial that has already seen its enrollment target and primary completion date revised multiple times since 2017.
No other industry trial is currently testing an IRAK4 inhibitor in primary CNS lymphoma, leaving emavusertib's combination approach as the only entrant on that specific axis even as BTK inhibitors broadly remain the established backbone therapy.
Curis says its FDA and EMA meetings from 2025 support the study's potential to back an accelerated approval filing, a plan that still depends on data maturity the company has not yet disclosed in full.

The disclosure

Curis, Inc. hosted a webcast on July 22, 2026 to present updated clinical data from CA-4948-101, the open-label TakeAim Lymphoma study of emavusertib (CA-4948) in relapsed or refractory primary CNS lymphoma. The update covered 7 BTK-naive patients and 39 BTKi-experienced patients as of the disclosure date. Curis Chief Executive Officer James Dentzer said the company is "especially excited by the results in the BTKi-experienced patients for whom there are no approved therapies, where emavusertib has shown it can reverse disease progression in patients currently progressing on a BTK inhibitor and enable them to achieve objective responses". The release did not attach a numeric objective response rate, confidence interval, or p-value to that claim. NCT03328078+1

The trial and its timing

The study first posted in November 2017 and has since carried an enrollment target of 152 patients, most recently set in January 2025 after moving through 110, 96, 181, 221, and 80 over prior amendments. Its primary completion date has shifted three times, from December 2020 to December 2022, then November 2023, then August 2026. The trial remains listed as Recruiting, with a primary completion date of August 1, 2026 and a full completion date of October 1, 2026. The company had guided a data readout for the second half of 2025; the update arrived 203 days after that window closed, following a run of enrollment and timeline revisions that predate this specific catalyst. NCT03328078

What the disclosure does and does not establish

The 46-patient cohort described in the update is open-label with no control arm, so it can show whether responses occur but cannot establish a comparative treatment effect against BTK-inhibitor monotherapy alone. The company frames BTK inhibitors as the established standard of care in relapsed or refractory PCNSL, citing response rates of 40% to 70% in BTKi-naive patients and generally poor outcomes, including progression to hospice or best supportive care, once patients progress on a BTK inhibitor. Against that backdrop, a qualitative claim of reversed disease progression in BTKi-experienced patients addresses a real unmet-need population, but the underlying counts and durability of those responses were not disclosed in the release. NCT03328078+1

The competitive field

No other industry trial currently tests an IRAK4 inhibitor in primary CNS lymphoma, leaving emavusertib's combination approach without a direct target-and-indication competitor to benchmark against. Field activity for IRAK4-targeted trials overall has declined, with 468 recent trials against 828 older ones. This leaves the disclosed responses standing largely on their own evidentiary terms rather than against a rival readout.

Regulatory framing and what remains open

Curis reiterated that it completed meetings with the FDA and EMA in 2025 and said the ongoing study "could support an application for accelerated approval in R/R PCNSL". Emavusertib holds orphan drug designation from both the FDA and the European Commission for PCNSL, granted in 2024 and 2025. An accelerated approval pathway typically rests on a surrogate endpoint such as response rate, which the company has not yet quantified in this disclosure, leaving the regulatory framing ahead of the data needed to support it. Curis+1

This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.