What randomized clinical trials are currently registered testing ivermectin, mebendazole or fenbendazole in cancer patients?

1. The hard fact: randomized trials are absent from the record

Multiple fact‑checks and reviews included in the reporting converge on the same conclusion: rigorous randomized clinical trials testing ivermectin or fenbendazole for cancer in humans are missing from the literature cited here ^{[4] [1]}. Factually and Anticancer Fund both flag the gap between promising laboratory data and the lack of randomized human evidence necessary to establish efficacy or safety for oncology indications ^{[1] [4]}.

2. What is registered and active: an early‑phase ivermectin + immunotherapy study

There is at least one active clinical trial evaluating ivermectin for cancer in humans: a phase 1/2 study combining ivermectin with two immunotherapy drugs for metastatic TNBC, which is described in the reporting and appears on ClinicalTrials.gov as NCT05318469 ^{[2] [3]}. The trial is early‑phase and, according to the coverage, designed to test safety and preliminary activity rather than to provide randomized efficacy data that would change practice immediately ^[2].

3. Mebendazole: the most human data among the benzimidazoles, but still not randomized

Among benzimidazole antiparasitics, mebendazole has generated the most human‑population data and interest for anticancer repurposing, yet the reporting emphasizes that human studies remain limited and that randomized trials are not established in the sources provided ^{[5] [6]}. Reviews and clinical commentaries portray mebendazole as the best‑studi ed candidate for translational work, but stop short of identifying ongoing randomized trials in patients ^{[5] [6]}.

4. Fenbendazole: preclinical promise, veterinary approval, and anecdote‑driven uptake

Fenbendazole, approved for veterinary use, shows anticancer activity in cell and animal models and has driven a wave of anecdotal case reports and compilations online, but the reporting stresses that rigorous human clinical trials—especially randomized trials—are lacking ^{[7] [8] [4]}. The prominence of case collections and celebrity anecdotes has increased public interest but does not substitute for controlled randomized trials ^{[8] [4]}.

5. Why the gap matters: biology vs. evidence

Laboratory data indicate multiple mechanisms by which ivermectin and benzimidazoles (including mebendazole and fenbendazole) could affect cancer cells—ranging from microtubule disruption to effects on signaling pathways—but translational hurdles remain, and reviewers caution that promising preclinical mechanisms do not equal proof of clinical benefit without randomized testing in humans ^{[9] [10] [5]}.

6. The research landscape and implicit agendas

The reporting shows a mixed ecosystem: peer‑reviewed preclinical work and small clinical efforts sit beside prolific case‑report compilations and popular promotion on social and alternative‑health sites; fact‑checkers and mainstream oncology outlets warn against conflating anecdote with evidence and point out ethical tensions when patients request unproven off‑label use ^{[8] [1] [11]}. Advocacy for repurposing inexpensive antiparasitics has a visible agenda—to accelerate affordable therapies—but that agenda can bias interpretation of sparse clinical evidence ^{[5] [8]}.

7. Bottom line for researchers and clinicians

Based on the supplied sources, the correct, evidence‑based statement is that no registered randomized clinical trials testing ivermectin, mebendazole, or fenbendazole in cancer patients are documented in the reporting; there is ongoing early‑phase investigation (notably the phase 1/2 ivermectin + immunotherapy trial) and a body of preclinical and anecdotal work that justifies further controlled study rather than clinical adoption today ^{[1] [2] [3] [4] [5]}.