Final results from a major phase 3 clinical trial suggest that atrasentan, an endothelin receptor antagonist, may offer meaningful benefits for patients living with IgA nephropathy — one of the most common causes of chronic kidney disease worldwide. The findings, published in The Lancet, emerge from the ALIGN study, which tracked outcomes over a 2.5-year period.
About the ALIGN Trial
The ALIGN trial was structured as a randomised, double-blind, placebo-controlled investigation — a design considered the gold standard for evaluating therapeutic interventions. Participants were assigned to receive either atrasentan or a placebo, with neither patients nor investigators aware of the treatment allocation during the study period. This rigorous methodology was intended to minimise bias and strengthen the reliability of the conclusions drawn.
IgA nephropathy, also known as Berger's disease, is characterised by the accumulation of immunoglobulin A in the kidneys, leading to inflammation and progressive damage. Elevated proteinuria — the presence of excess protein in the urine — is a key marker of disease activity and a recognised predictor of long-term kidney decline. Slowing that decline remains a central goal of ongoing research in this area.
Key Findings on Proteinuria and Kidney Function
According to the trial results, atrasentan was associated with a measurable reduction in proteinuria among participants over the full 2.5-year duration. Alongside this, the drug appeared to support the preservation of kidney function compared with placebo — a finding that researchers described as clinically significant given the progressive nature of the condition.
The study also examined whether the concurrent use of SGLT2 inhibitors — a class of agents increasingly used in kidney and cardiovascular disease management — had any bearing on outcomes. The beneficial effects attributed to atrasentan were observed consistently, irrespective of whether patients were also taking SGLT2 inhibitors. This finding may carry practical relevance as combination therapy becomes more common in the management of chronic kidney conditions.
Tolerability Profile
Atrasentan was reported to be well tolerated across the trial population. Tolerability data are particularly important in the context of IgA nephropathy, where patients may already be managing multiple medications and where long-term adherence to any new treatment is essential for sustained benefit. The absence of significant safety signals over the 2.5-year period adds to the profile of the drug as a potential therapeutic option.
Context Within IgA Nephropathy Research
The ALIGN results arrive at a time of growing interest in targeted therapies for IgA nephropathy. For decades, treatment options were largely limited to supportive care and broad immunosuppressive strategies. In recent years, a clearer understanding of the disease's molecular pathways has opened the door to more specific interventions, of which atrasentan represents one example.
Endothelin receptor antagonists like atrasentan work by blocking the action of endothelin-1, a potent vasoconstrictor that contributes to kidney inflammation and fibrosis. By interrupting this pathway, the drug is thought to reduce the haemodynamic and inflammatory pressures that accelerate kidney damage in IgA nephropathy.
The phase 3 designation of the ALIGN trial places these findings at an advanced stage of clinical evaluation. Phase 3 trials are typically the final step before regulatory review, and their outcomes carry considerable weight in informing treatment guidelines and approval decisions.
Implications for Future Research
While the ALIGN results are being characterised as final for this particular trial phase, questions remain about longer-term outcomes beyond the 2.5-year window, optimal patient selection, and how atrasentan might be positioned alongside existing and emerging therapies. Researchers and clinicians working in nephrology are likely to scrutinise these data closely as the field continues to evolve.
The full findings are available in The Lancet.