November 28, 2018

Anti-malaria drugs such as hydroxychloroquine are common treatments for arthritis and heat rash in patients with lupus. A new study by Target Identification in Lupus grantee Keith Elkon, MD, of the University of Washington, Seattle, and colleagues suggests that a new drug they designed works better than the commonly prescribed hydroxychloroquine in an experimental model. Recently published in the well-respected journal Arthritis & Rheumatology, these results represent a promising step toward testing the drug in clinical trials.

Patients with lupus produce excess type I interferons, molecules that stimulate the immune system to attack the body’s own tissues rather than bacteria and viruses. Although hydroxychloroquine and other anti-malaria drugs can reduce the levels of type I interferons, they have limited effects on serious disease manifestations.  Dr. Elkon and his colleagues had developed a new drug known as X6 that may be safer and more powerful.

In their new study, Dr. Elkon’s team compared the drug X6 to hydroxychloroquine in mice that carry a mutation found in some patients with lupus. The researchers discovered that X6 diminished the amount of type I interferons in the animals, while hydroxychloroquine did not.  X6 was also better at reducing heart inflammation, a symptom that may occur in some patients with lupus. The results suggest that X6 is superior to hydroxychloroquine in this experimental model. Next scientists will need to perform further tests with mice and with human cells to determine if the drug is safe and effective enough to test in clinical trials with lupus patients.