CaRe Prostate Study of INKmune in Metastatic CRPC Hits Primary, Secondary End Points

The phase 1/2 CaRe Prostate trial (NCT06056791) of INKmune for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC) has met its primary and secondary end points.1 The study is now closed to further enrollment.

Topline data from CaRe Prostate revealed that INKmune was well tolerated at all 3 dose levels that were evaluated in the study. Moreover, patients with low natural killer cell activation experienced the greatest improvement in terms of biomarkers of natural killer cell activation.

“INKmune was safe and effective at activating natural killer cells in a subset of more than half of these patients with advanced disease,” Mark Lowdell, PhD, MSc, the chief strategy officer and cofounder of INmune Bio, stated in a news release. “Excitingly, we did see, in some patients, individual tumor lesions either reducing in size or completely disappearing during treatment, so we believe this could be evidence of a direct effect on tumor cell killing.”

INKmune is a replication-incompetent human tumor cell line that conjugates to resting which is designed to conjugate to patients’ resting natural killer cells. This mechanism of action leads to the delivery of multiple essential priming signals to convert the patient’s resting natural killer cells into tumor-killing memory-line natural killer cells.

CaRe Prostate was an open-label dose escalation and expansion trial of INKmune for the treatment of patients with metastatic CRPC.2 Eligible patients needed to have blood prostate specific antigen (PSA) levels above 1 ng/mL at the time of screening, an ECOG performance status of 0 or 1, have experienced disease progression following treatment with androgen deprivation therapy (ADT) and at least 1 androgen receptor inhibitor, have not received more than 3 therapies beyond ADT, and have a castrate level of testosterone of less than 50 ng/dL and adequate organ function.

Those with a diagnosis of small cell or neuroendocrine prostate cancer; a history of concurrent malignancies within the previous 3 years, except in situ carcinomas and nonmelanoma skin cancer; and uncontrolled autoimmune disease, were not included on the study.

During the dose escalation phase, eligible patients received intravenous INKmune at 1 x 108, 3 x 108, or 5 x 108 cells. Patients received 3 weekly doses of INKmune on days 1, 8, and 15. During the dose expansion phase, patients received INKmune at up to 2 optimal dose levels no higher than the maximum tolerated dose (MTD).

The primary outcomes of CaRe Prostate consisted of the percentage of blood activated natural killer cells, the rate of PSA response of at least 30% (PSA30), prostate-specific membrane antigen levels, changes in circulating tumor DNA, determining the MTD, and safety and tolerability. Secondary outcomes included the overall clinical efficacy of INKmune, the rate of PSA responses of at least 50%, the time period of PSA30, progression-free survival (PFS), radiologic PFS, objective response rate, disease control rate, and overall survival.

In light of the positive findings from CaRe Prostate, INmune Bio announced in the news release that it plans to design a randomized phase 2b trial that will examine INKmune in patients with castration-resistant prostate cancer with less severe disease.1

References

1. INmune Bio’s CaRe PC trial of INKmune™ in metastatic castration-resistant prostate cancer meets endpoints and is closed to enrollment. News release. INmune Bio. August 4, 2025. Accessed August 4, 2025. https://www.inmunebio.com/index.php/newsroom/2025-news/muneiosaerialofmuneinetastaticas20250804050503
2. Study of INKmune in patients with mCRPC (CaRe Prostate) (CaRe). ClinicalTrials.gov. Updated May 13, 2025. Accessed August 4, 2025. https://clinicaltrials.gov/study/NCT06056791