Vertex preps FDA filing for IgAN drug after phase 3 readout
Vertex's chief executive, Reshma Kewalramani.
Vertex Pharma's bid to expand beyond its cystic fibrosis franchise has taken a big step forward, thanks to positive late-stage clinical data for povetacicept in kidney disorder immunoglobulin A nephropathy (IgAN).
The readout from the RAINIER trial means that Vertex is now preparing to file the dual BAFF/APRIL inhibitor for accelerated approval in the US before the end of this month.
Vertex acquired povetacicept as part of its largest-ever acquisition, the $4.9 billion takeover of Alpine Immune Sciences in 2024. The drug was the showpiece of the deal, and Vertex has described it as a 'pipeline-in-a-product' with potential in other indications, including lupus nephritis and autoimmune cytopenias, that could lead to multibillion-dollar sales.
Treatment options are expanding for IgAN – a rare autoimmune kidney disorder and a leading cause of kidney failure, in which antibodies accumulate in the kidneys, causing inflammation and scarring – but Vertex reckons povetacicept's monthly, self-administered dosing could give it an edge in the market.
Interim results from RAINIER reveal that an 80 mg dose of povetacicept every four weeks delivered a 52% reduction in protein in urine – a biomarker for kidney damage – from baseline over 36 weeks, which compared to a 4.3% fall in patients who received a placebo.
There was also a 79% reduction in serum levels of an antibody linked to IgAN (Gd-IgA1) compared to placebo, a key secondary endpoint, while resolution of blood in the urine was seen in 85% of patients treated with the drug, a 61% improvement over placebo.
The data was deemed "remarkable" by Vertex chief executive Reshma Kewalramani, and investors in the company appeared to agree, driving its share price up more than 8% to nearly $500 and pushing its valuation towards $127 billion.
"As a nephrologist, I am struck by the rapid, deep, and sustained response to povetacicept, as well as the consistency of benefit across all subgroups," she added.
Analysts at BMO Capital Markets, reported by Reuters, said the results "firmly place povetacicept as a clear competitor and potential leader in IgAN," with efficacy that is competitive against Otsuka's recently approved anti-APRIL antibody Voyxact (sibeprenlimab) and Vera Therapeutics' dual BAFF/APRIL inhibitor ataticept, which has been submitted to the FDA with a decision due by 7th July.
Vertex recorded revenues of $12 billion in 2025, mainly from its CF products, and is expecting to see growth to around $13 billion this year, with a $500 million-plus contribution from non-CF products, which include sickle cell disease (SCD) and transfusion-dependent beta thalassaemia (TDT) gene therapy Casgevy (exagamglogene autotemcel).
