Which cancer types have been investigated in clinical trials of ivermectin and what phases were those trials?
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Executive summary
Clinical investigation of ivermectin in human cancer patients is extremely limited: the only clearly documented clinical trial testing ivermectin in cancer patients is a phase I/II study for metastatic triple‑negative breast cancer (mTNBC) (ClinicalTrials.gov NCT05318469 / ASCO abstract) [1][2]. Several reviews and older papers emphasize that, outside of that registered study, clinical evidence is scarce and most data remain preclinical (cell lines and animal studies) [3][4][5].
1. The single active human trial: metastatic triple‑negative breast cancer (Phase I/II)
The principal—and most frequently cited—clinical effort is a phase I/II, open‑label study combining oral ivermectin with an anti‑PD‑1 immunotherapy agent (balstilimab or pembrolizumab) in patients with metastatic triple‑negative breast cancer, registered as NCT05318469 and reported by Gateway for Cancer Research and in an ASCO 2025 abstract [1][2]. Protocol descriptions and coverage indicate the trial tests safety, tolerability and preliminary efficacy (tumor shrinkage, progression‑free survival, overall survival) and includes expansion cohorts such as PD‑L1‑negative TNBC; it is explicitly described as Phase I/II in the trial listing and meeting abstract [1][2].
2. Conflicting claims and other registry mentions: sparse additional registrations
Some secondary reporting identified two registered studies when searching ClinicalTrials.gov, mentioning NCT05318469 and another entry (NCT02366884) described as a phase II trial in a different context, but primary registry pages and peer‑reviewed reviews emphasize that only the phase I/II TNBC trial is active and prominent in the literature [6][1]. Reviews and systematic discussions caution that earlier literature mainly documents preclinical anticancer effects and explicitly state that clinical trials of ivermectin as an anticancer agent have been largely absent until very recently, underscoring a persistent gap between lab findings and human testing [5][4].
3. What cancer types have appeared in preclinical vs clinical records
A large body of preclinical work has explored ivermectin effects across many cancer cell lines—breast cancer, glioblastoma, pancreatic, cervical, ovarian, colon and others—but these remain in vitro or animal studies rather than randomized human trials [3][7][5]. The only cancer type moved into formal human testing, based on available reporting, is triple‑negative breast cancer (mTNBC) via the phase I/II trial; references to other cancer types in human trials are not substantiated by primary trial reports in the provided sources [1][2][5].
4. Trial phase context and expert caveats
Authors of reviews and clinical commentators stress that even promising phase I/II results would still require larger randomized phase III trials to establish efficacy and safety for routine oncology use, and they warn against extrapolating in vitro potency to clinical benefit because effective in‑lab concentrations often exceed achievable human plasma levels [4][8]. Medical commentary and news pieces further note oncologists’ concern about patients self‑medicating based on preclinical hype; the community frames current clinical work as exploratory rather than practice‑changing [4][9].
5. Bottom line and reporting limitations
Based on the documents reviewed, metastatic triple‑negative breast cancer (mTNBC) is the only cancer type clearly enrolled in a registered human ivermectin trial and that trial is Phase I/II (NCT05318469) [1][2]. Multiple high‑quality reviews state that, until recently, no human anticancer trials existed and that most evidence remains preclinical—there is no large‑scale randomized clinical evidence supporting ivermectin as a cancer treatment at this time [5][4]. The reporting examined does not provide published phase I/II outcomes or confirm additional completed human trials for other cancer types, so assertions beyond the cited TNBC study would exceed the available sources [1][2][5].