​​​Early results from an ongoing clinical trial suggest that a new drug being explored for treating IgA nephropathy, called atacicept, is safe and very beneficial for patients. The results, published in the New England Journal of Medicine, show the novel treatment can reduce the amount of protein leaking from patients' kidneys by nearly half after just 36 weeks of treatment. 

IgA nephropathy occurs when a person's immune system creates abnormal protein complexes, which can build up in the kidneys. In at least 50% of people with the condition, this accumulation of abnormal immune proteins can lead to kidney failure. 

Dr. Sean Barbour is a researcher at the University of British Columbia's Division of Nephrology who has led a number of studies exploring novel treatments for IgA nephropathy. He notes that conventional therapies, such as prednisone, work by generally suppressing the immune system, but these come with many side effects. “You might use it for six or nine months, but the disease tends to relapse afterwards," he adds. 

Fortunately, more targeted medications for IgA nephropathy are being explored, including atacicept. Atacicept works by only modifying a particular part of the immune system, called B cells, which play a role in creating the large, kidney-damaging protein complexes associated with IgA nephropathy. 

As part of an international study across 31 countries, Barbour and his colleagues launched a phase III clinical trial to test the efficacy of atacicept. They recruited more than 200 patients with IgA nephropathy, roughly half of whom received an injection of atacicept once a week, while the other half received a placebo. 

Notably, the researchers found that patients given atacicept showed decreased levels of the harmful proteins associated with IgA nephropathy after just four weeks of treatment. “Those [proteins] decreased quite substantially in the treatment group, which gives you some idea that the drug is targeting the underlying drivers of the disease," Barbour explains.

After 36 weeks of treatment, the amount of protein leaking into patients' urine – a symptom called proteinuria and which indicates kidney damage – was reduced by 46% in people given atacicept, but only 7% in the placebo group. What's more, the people who received atacicept experienced few side effects. The most common side effect was a reaction at the injection site. 

Barbour cautions that these results are only from the first 36 weeks of the study, which is ongoing. Whereas proteinuria is used to estimate kidney damage, the researchers will need to follow study participants for two years to confirm whether atacicept truly helps protect kidney function over time. Barbour says these longer-term data can be used to approve atacicept for IgA nephropathy patients in Canada and globally who would benefit from more targeted therapies. 

Study: A Phase 3 Trial of Atacicept in Patients with IgA Nephropathy