Janux Therapeutics (JANX) Announces Doses Selected for Phase 1b Expansion Trials Supported by Encouraging Efficacy and Safety Profile Observed in Phase 1a Dose Escalation for JANX007 in mCRPC
Janux Therapeutics, Inc. (Nasdaq: JANX) (Janux), a clinical-stage biopharmaceutical company developing a broad pipeline of novel immunotherapies by applying its proprietary technology to its Tumor Activated T Cell Engager (TRACTr) and Tumor Activated Immunomodulator (TRACIr) platforms, today announced positive updated interim clinical data for its JANX007 clinical program. Janux will host a virtual event today at 4:30 PM ET. To register for the event, please click here.
“These clinical data show substantial activity with JANX007 in 5L metastatic castration-resistant prostate cancer patients and provide compelling support for the doses we’ve selected for expansion trials directed at pre-PLUVICTO® 2L and 3L patients,” said David Campbell, Ph.D., President and CEO, Janux Therapeutics. “We look forward to rapidly advancing JANX007 into second and third-line therapy where a substantial unmet need remains and where we believe JANX007’s highly differentiated profile could allow for broad usage, if approved. This is an exciting day for Janux, but more importantly the prostate cancer patients we serve.”
Updated interim, clinical data for PSMA-TRACTr JANX007 in mCRPC as of November 15, 2024
JANX007 is in a Phase 1a clinical trial in patients with advanced or metastatic prostate cancer (mCRPC). The patients enrolled in the trial were heavily pre-treated with a median of four prior lines of therapy. As of the November 15, 2024 data cutoff, 16 pre-PLUVICTO® patients have been treated once-weekly at a target dose ranging from 2 mg to 9 mg in the Phase 1a clinical trial. High prostate-specific antigen (PSA) response rates and deep PSA declines were observed across all doses; 100% of patients achieved best PSA50 declines, 63% of patients achieved best PSA90 declines, and 31% of patients achieved best PSA99 declines. Durability of PSA declines at a target dose ≥ 2 mg were observed; 75% of patients maintained PSA50 declines at ≥ 12 weeks and 50% of patients maintained PSA90 declines at ≥ 12 weeks. Deep and durable PSA responses were observed irrespective of resistance driver aberration status, or prior treatments with a taxane or ARPi. In RECIST-evaluable patients, anti-tumor activity was observed with confirmed and unconfirmed partial responses in 50% (4/8) of patients.
JANX007 was well-tolerated with cytokine release syndrome (CRS) and CRS-related adverse events primarily limited to cycle 1 and grades 1 and 2. Similarly, treatment-related adverse events (TRAEs) not associated with CRS were primarily limited to cycle 1 and grades 1 and 2. The maximum tolerable dose for JANX007 has not yet been reached.
Based on these efficacy and safety results, two once-weekly step dose regimens have been identified for Phase 1b expansion trials directed at pre-PLUVICTO® 2L and 3L patients. Janux anticipates providing another update on JANX007 in 2025.
Webcast Information
Janux will host a live webcast today at 4:30 PM ET. A live question and answer session will follow the formal presentation. To register for the event, please click here.
Participant Dial-In Details
USA & Canada: (800) 715-9871
International: 1 (646) 307-1963
Conference ID: 2229349
To access the live webcast, please visit the Investors section of the Company's website. A replay of the webcast presentation will be available on the Company's website at https://investors.januxrx.com for at least 30 days.
Janux’s TRACTr and TRACIr Pipeline
Janux’s first clinical candidate, JANX007, is a TRACTr that targets prostate-specific membrane antigen (PSMA) and is being investigated in a Phase 1 clinical trial in adult patients with mCRPC. Janux’s second clinical candidate, JANX008, is a TRACTr that targets epidermal growth factor receptor (EGFR) and is being studied in a Phase 1 clinical trial for the treatment of multiple solid cancers including colorectal carcinoma, squamous cell carcinoma of the head and neck, non-small cell lung cancer, renal cell carcinoma, small cell lung cancer, pancreatic ductal adenocarcinoma and triple-negative breast cancer. We are also generating a number of additional TRACTr and TRACIr programs for potential future development, some of which are at development candidate stage or later. We are currently assessing priorities in our preclinical pipeline.