Have any completed human studies reported safety or pharmacokinetics of high‑dose ivermectin in cancer patients?
Executive summary
No completed human studies specifically reporting the safety or pharmacokinetics (PK) of high‑dose ivermectin in cancer patients have been published in the sources provided; the literature instead contains PK/safety data from healthy volunteers and non‑cancer patient groups and multiple preclinical cancer studies, with early-phase cancer trials registered or in progress but not reported as completed in these sources [1] [2] [3] [4] [5].
1. High‑dose ivermectin has been studied in humans, but in healthy volunteers, not cancer patients
A pivotal, double‑blind, placebo‑controlled, dose‑escalation study examined safety, tolerability, and pharmacokinetics of escalating high doses of ivermectin in healthy adult subjects and found the drug generally well tolerated at regimens up to single doses of ~120 mg (≈2 mg/kg) and multidose schedules described in that trial [1]; reviews and pharmacology papers repeatedly cite Guzzo et al. as the human PK source when projecting whether plasma concentrations needed for anticancer effects are “clinically reachable” [6] [2].
2. No published clinical trials report safety/PK in patients with cancer — reviews and clinical summaries concur
Multiple recent reviews and specialty updates examining ivermectin’s anticancer potential note that clinical data in cancer patients are absent and that existing human evidence is limited to volunteer or antiparasitic patient PK studies and to preclinical models (cell lines and animals) rather than completed oncology trials [7] [8] [4] [9]. Oncology commentators warn that the doses producing antitumor effects in mice may be toxic in humans and emphasize the lack of human efficacy or cancer‑patient safety data to support off‑label use [5] [10].
3. Early‑phase cancer trials exist but are not reported as completed in the supplied reporting
Clinical trial registries and conference abstracts indicate investigators have planned or opened phase I/II studies combining ivermectin with anticancer agents (for example, an NCI‑linked trial identifier and an ASCO abstract describing a phase I/II study of ivermectin plus balstilimab in metastatic triple‑negative breast cancer), signaling movement from bench to bedside, but the sources provided do not show completed, peer‑reviewed reports of safety or PK results from cancer patients in those trials [11] [3] [12]. Consequently, no cancer‑patient‑specific PK parameters (Cmax, AUC) or formal safety profiles at high doses in oncologic contexts are available in these materials [3] [4].
4. What can be cautiously inferred, and where the evidence gaps remain
Human PK and safety data from the volunteer studies establish that higher plasma ivermectin concentrations are achievable and were generally tolerated in healthy adults, and some cancer preclinical work cites those PK numbers when arguing translational plausibility (for example, reported detection of micromolar levels at ~2 mg/kg in volunteers) — but translating volunteer PK/safety into cancer patients (who often have organ dysfunction, polypharmacy, and altered tolerance) is not supported by completed patient studies in the provided sources [1] [6] [2]. The supplied literature repeatedly stresses that most anticancer findings remain in vitro or in animal models and that rigorous clinical trials are needed to define safe doses, drug interactions, and whether anticancer exposures are achievable without unacceptable toxicity in patients [8] [9] [5]. Given these limits, the responsible interpretation of the sources is: human high‑dose ivermectin PK and safety have been reported, but not in completed studies of cancer patients — ongoing trials may fill that gap, but no completed cancer‑patient safety/PK reports are shown in the reviewed material [1] [3] [4].