Phase II clinical trial evaluating the effects of anti-inflammatory drug celecoxib as treatment for breast cancer patients

This phase II clinical trial evaluated the effect of the drug celecoxib (Celebrex) as treatment for patients with breast cancer. 

Inflammation is one of the body's natural responses to injury and may play a role in cancer formation. Inflammation is controlled in part by a type of hormone produced by cells called cyclooxygenase – derived prostaglandins (COX). At the present, there are 2 types of COX known: COX-1 and COX-2. COX-2, in particular, is linked to inflammation and has been associated with cancer formation. Recent studies have found that COX-2 is over-produced (over-expressed) in breast cancer tissue. Therefore, drugs that block COX-2 may represent a treatment option for patients with breast cancer. Celecoxib is an anti-inflammatory drug which blocks the production of COX-2 in the cells. It is usually given for the treatment of inflamed (swollen) joints, menstrual cramps and acute pain. This study examined the effect of the COX-2 inhibitor celecoxib as treatment for breast cancer.

This study included 37 women diagnosed with early stage breast cancer. Patients were randomly chosen to receive either celecoxib twice daily or a placebo (a substance with no medical effect used as a control when testing new drugs) for 2 to 3 weeks before surgery to remove the cancer. The authors of the study took samples of the cancer in the breast tissue and analyzed the proteins on the surface of the cancer cells as a way of determining whether celecoxib had an effect on cancer growth.

They found that after 2 to 3 weeks of treatment with celecoxib a large number of proteins in the cancer cells were affected by the drug. Moreover, the expression of Ki-67 (a protein associated with cells’ growth) in breast cancer cells decreased by 29.1% in patients who were given celecoxib, compared to patients who received placebo who only had an 8.2% decrease. 

In summary, in this study, patients treated with celecoxib showed a decrease in proteins that promote cancer growth expressed by breast cancer tissue, indicating that this drug could slow the growth of cancer cells.

This was a phase II clinical trial that included a very small number of patients. Also, patients were followed for a short period of time. Future larger clinical trial, with longer follow up periods are expected in order to confirm the results of this study and to determine the real benefits of celecoxib on breast cancer patients’ survival.

This study was funded by Pfizer, the manufacturer of Celebrex.