0
0
TUCSON, AZ – April 19, 2025 – An inexpensive drug typically used to treat pinworm infections, pyrvinium pamoate, has shown promise in halting and potentially reversing the growth of Merkel cell carcinoma (MCC), a rare but particularly aggressive form of skin cancer, according to new research. The findings, led by scientists at the University of Arizona Cancer Center, were recently published in the Journal of Clinical Investigation.
Merkel cell carcinoma is a neuroendocrine cancer known for its rapid growth and high mortality rate, being three to five times more likely to be fatal than melanoma. Current treatment options, including surgery, radiation, and immunotherapy, have limited success rates, highlighting an urgent need for new therapeutic strategies.
“Merkel cell carcinoma is increasing in incidence,” stated senior author Dr. Megha Padi, a member of the U of A Cancer Center and an assistant professor in the U of A College of Science. “Even though it’s a rare cancer type, it mimics a lot of properties that other cancers have.”
Pyrvinium pamoate, approved by the U.S. Food and Drug Administration (FDA) back in 1955, has previously hinted at anti-tumor activity in studies involving breast, colorectal, pancreatic, and bladder cancers. However, this marks the first time its effects have been investigated specifically in models of Merkel cell carcinoma.
The research team discovered that pyrvinium pamoate effectively inhibited the growth of MCC cells in laboratory settings and also reversed the cancer’s characteristic neuroendocrine features. Furthermore, in mouse models designed to mimic human MCC, the drug significantly reduced tumor growth.
The researchers targeted pyrvinium pamoate after identifying the Wnt signaling pathway as a crucial molecular mechanism driving the transformation of normal cells into MCC. Pyrvinium pamoate is known to inhibit this specific pathway.
Dr. Padi offered a potential explanation for why an antiparasitic drug might combat cancer: “This is a hypothesis, but some people think the reason an antiparasitic agent could be effective against cancers is because tumors are a little bit like parasites in our body.” She elaborated that both tumors and parasites need to exploit the host’s resources to fuel their rapid multiplication. “If the pathways that they have hijacked to feed themselves are the same, then you get lucky, and you have a tumor type that could be amenable to killing by these antiparasitic drugs.”
While these initial results are encouraging, the researchers stress that significant further research is required. Optimizing treatment protocols and conducting clinical trials are necessary next steps before pyrvinium pamoate could potentially be developed into a standard treatment for patients with Merkel cell carcinoma.
Disclaimer: This article reports on early-stage research findings published in a peer-reviewed scientific journal. The information presented is not intended as medical advice. Individuals should consult with qualified healthcare professionals for any health concerns or before making any decisions related to their treatment or health. The findings require further investigation and clinical validation before this drug can be considered a treatment option for Merkel cell carcinoma.
