Which oncology trials tested ivermectin and what were their cancer types and phases?
Executive summary
Clinical testing of ivermectin in human oncology is extremely limited and concentrated in early-phase trials for metastatic triple‑negative breast cancer (mTNBC), notably a phase I/II (sometimes reported as phase 1/2) combination study of ivermectin with checkpoint inhibitors (balstilimab or pembrolizumab) — ClinicalTrials.gov identifier NCT05318469 — whose preliminary abstract reported 8 evaluable patients with one partial response, one stable disease and six progressions [1] [2]. Most other evidence is preclinical (cell lines, mouse models) and reviews note no large randomized trials to establish efficacy in cancer [3] [4].
1. A single identifiable human trial: mTNBC combination study
The clearest human study repeatedly cited in the literature is a phase I/II (reported also as phase 1/2) trial testing ivermectin given with immune checkpoint inhibitors in patients with metastatic triple‑negative breast cancer (NCT05318469). This trial was presented as an abstract at ASCO 2025 and listed on ClinicalTrials.gov; preliminary results described eight evaluable patients with one partial response, one stable disease and six progressions, and authors characterized the combination as “safe and well tolerated” while concluding further study was warranted [1] [2].
2. How journalists and oncology outlets describe the ASCO abstract
Coverage from specialty outlets and patient information sites interprets the ASCO abstract conservatively: several pieces note the trial showed “no real benefit” or only minimal signal in a tiny cohort, and emphasize that oncologists remain skeptical pending larger randomized studies [5] [6] [7]. OncologyNewsCentral and PatientPower both highlight the limited patient numbers and stress that preclinical promise has not translated into clear clinical benefit to date [5] [6].
3. Preclinical evidence is broad but not equivalent to clinical proof
Laboratory and animal studies are extensive across cancer types (breast, pancreatic, colorectal, glioblastoma and others). Preclinical papers show ivermectin can induce cancer cell death, modulate immune responses (e.g., “converts cold tumors hot” in breast models), and synergize with other agents in cell lines and mice — but these are not clinical results [8] [9] [10]. Reviews consistently warn that in vitro/in vivo doses and settings differ from safe, effective human dosing, and that clinical evidence remains scarce [11] [12] [3].
4. What systematic reviews and specialty papers report about clinical trials
Recent reviews and focused articles on gynecologic and other cancers state there are no other registered trials of ivermectin for cancer listed on NCI or similar registries beyond the mTNBC combination, and that clinical studies are mostly limited to cell-line work rather than human trials [13] [4]. A 2025 PubMed review explicitly calls out the absence of large randomized controlled trials confirming benefit and warns about risks from self-medication driven by social media [3].
5. Ongoing questions, timelines and what to watch for
The ASCO abstract is a first clinical signal and the trial was reported as continuing enrollment with expected completion timelines noted in coverage (some outlets cited an expected finish by 2026), but even optimistic reporting stresses that any positive signal would still require a phase 3 randomized test to change practice [7] [1]. Independent outlets and clinicians call attention to the dose, schedule, combination partner, and translation of murine dose–response to humans as critical unresolved issues [14] [8].
6. Alternative viewpoints and potential agendas
Advocates for drug repurposing highlight ivermectin’s low cost and substantial preclinical signal across tumor types as reasons to test it in cancer; critics and mainstream oncologists emphasize safety, pharmacokinetics and the historical lesson of ivermectin’s misplaced promotion during the COVID‑19 pandemic, cautioning against off‑label use outside trials [15] [16] [3]. Patient‑facing sites and some nonprofits push fundraising and preclinical programs that could lead to human trials; clinicians and peer reviewers stress the need for rigorous randomized data before recommending use [17] [18].
Limitations and final note: available sources identify one concrete human trial (the phase I/II combination in metastatic TNBC, NCT05318469) and numerous preclinical studies; they do not list other completed randomized oncology trials of ivermectin, nor do they provide detailed phase‑by‑phase registries beyond that TNBC study [13] [4] [1]. If you want, I can pull the ClinicalTrials.gov entry (NCT05318469) text and dates from the provided sources for a timeline and protocol summary [1].