Pimozide, a fairly common antipsychotic drug developed in the ‘60s, has shown to be surprisingly effective in fighting triple negative breast cancer, the most difficult to treat a form of the disease. Part of the diphenylbutylpiperidine class, it was primarily meant for patients suffering from schizophrenia or Tourette syndrome.
“Triple-negative breast cancer has lower survival rates and increased risk of recurrence. It is the only type of breast cancer for which only limited targeted treatments are available. Our research has shown that Pimozide could potentially fill this gap. And because this drug is already in clinical use, it could move quickly into clinical trials”, said Professor Mohamed El-Tanani, the lead investigator.
While there have been previous claims that certain neuroleptics could have an influence over cancer, there has never been any actual data to support them, until now.
The team comprised of doctors from the University of Bradford, Queen’s University Belfast and the University of Salamanca, tested Pimozide on samples of triple negative breast cancer, non-small cell lung cancer and normal breast cells. In high doses, the drug was able to eradicate up to 90% of all abnormal cells, leaving most of the healthy tissue unaffected.
Tests conducted on mice that had implanted cancerous cells performed similarly. Their tumors were 65% smaller and fewer in number, by 61%. Pimozide also helped to prevent metastasis in 94% of cases.
The reason for choosing this particular product was the effect it has on the Ran-GTP protein. Dr. El-Tanani explained: “Our study shows that by acting as a Ran-GTP inhibitor, Pimozide was able to block a number of key pathways that contribute to triple negative breast cancer growing and spreading”.
Additionally, the researchers observed another interaction, the drug also suppresses the VEGFR2 protein which is responsible for supplying blood to the tumors, promotes its growth and is linked with metastasis.
The next step would be human trials, though no specific time frame has been set.