ERA 2022 – Chinook’s second bird could also fly

Investors in Chinook Therapeutics will be focused on next year’s pivotal data with the group’s lead project, atrasentan, in the rare kidney disease IgA nephropathy. But early results released today suggest that the group’s follow-up asset, BION-1301, could also have promise. True, the data, reported at the European Renal Association meeting, come from just eight patients in the first cohort of a phase 1/2 trial. But a proteinuria reduction of nearly 50% at six months, if it holds up, would make BION-1301 look competitive with Calliditas’s Tarpeyo and Travere’s sparsentan. Chinook, whose stock climbed 11% this morning, plans a phase 3 study next year. The table below shows that there could soon be plenty of competition in IgAN, a disease that affects just 150,000 people in the US, Chinook estimates. But there were also positive signs yesterday from the first drug launched in the indication, with Calliditas reporting first-quarter Tarpeyo sales of $1.9m, a number well received by investors. Stifel analysts estimate first-year Tarpeyo revenues of $40m, though, so Calliditas still has a long way to go.