Tapeworm Drug Shows Promise for Endometriosis Treatment in Early Studies
Researchers are investigating a repurposed drug, niclosamide, modified for targeted delivery, as a potential new treatment for the debilitating condition.
A decades-old drug used to treat tapeworm infections is showing potential as a new therapeutic option for endometriosis, a painful condition affecting millions of women. Scientists have developed a highly targeted version of the drug, niclosamide, which in animal tests has demonstrated an ability to shrink the lesions associated with the disease.
Endometriosis occurs when tissue similar to the lining of the uterus, the endometrium, grows outside the uterus. This tissue can spread to organs such as the ovaries, bowel, bladder, and in some rare cases, even the lungs or brain. It behaves like uterine tissue, swelling and bleeding during menstruation, leading to inflammation, pain, and scar tissue formation. The condition is also a significant contributor to female infertility, and diagnosis often takes over nine years due to low awareness.
Current treatments for endometriosis range from over-the-counter pain relievers and hormonal contraceptives to surgery for tissue removal, and in severe cases, hysterectomy. Niclosamide has emerged as a candidate for a new treatment because research suggests it can inhibit key signaling pathways involved in cell growth, making it a subject of investigation for various diseases, including COVID-19, diabetes, and several types of cancer.
A Novel Delivery Method
Oral forms of niclosamide are not easily absorbed into the bloodstream and primarily remain in the gut, limiting their effectiveness for reaching endometriosis lesions. To overcome this, researchers at Washington State University created a water-soluble, dendrimer-based structure designed to carry the drug. This scaffolding, impregnated with niclosamide and folic acid, targets immune cells expressing FR-beta, a protein that congregates in areas of inflammation and is found in high concentrations within endometrial lesions.
When injected into the abdomen of mice genetically engineered to have endometriosis, the drug-laden dendrimers successfully delivered the niclosamide payload directly into the FR-beta-expressing immune cells. The study, published in Advanced Healthcare Materials, found that a significant number of mice treated with the drug showed no detectable lesions and exhibited reduced pain sensitivity within two weeks. The effects persisted for at least two weeks post-treatment.
Anjali Sharma, an associate professor of pharmaceutical sciences at the University of Michigan and a member of the research team, stated, "One of the major challenges has been developing treatments that are both effective and safe for long-term use. Our goal is to address the underlying disease pathology and ultimately improve the quality of life for millions of women."
Early Stage Research
While these results are promising, experts caution that this research is in its initial stages. Andrew Horne, a professor of gynaecology and reproductive sciences at the University of Edinburgh, noted that targeting the immune system is a promising approach and that repurposing an existing drug could accelerate development. However, he emphasized that the study was conducted on mice, which do not naturally develop endometriosis or experience menstruation, meaning human responses may differ.
Further research is needed to assess the long-term safety and efficacy of this treatment in humans, including determining optimal dosage and frequency of administration. The researchers hope that if successful, the injectable niclosamide could eventually be administered as a bi-weekly injection.
