In FDA double header, regulators also offer a green light to Rigel's fostamatinib
Fast on the heels of Ultragenyx’s big FDA win, Rigel $RIGL came through with an FDA approval for fostamatinib, a new second-line therapy for thrombocytopenia in adult patients with chronic immune thrombocytopenia. The therapy will be sold as Tavalisse.
The news spread fast on Twitter after the FDA posted the label for the drug, which arrived just days after someone at the company accidentally posted a notice of the OK ahead of the official word.
So let’s say this wasn’t entirely unexpected at Rigel.
Nevertheless, it was celebrated by investors, who have seen the stock go on a roller coaster ride on good and bad news over the years. The stock was up 12% Wednesday morning in pre-market trading.
One earlier plunge in the stock price was triggered by a positive but unimpressive 18% response rate for immune thrombocytopenia patients who achieved a stable platelet response. That was exactly the same rate seen in the second Phase III, except that one patient on a placebo also achieved a stable platelet response, and that scuttled any shot at hitting the primary endpoint. For analysts who had been looking for a response rate at least in the low 20s with clear signs of efficacy, the stumble did not play well.
The FDA, though, was willing to give it a green light for marketing without a panel review, perhaps underscoring a sense that regulators are quick these days to overlook the gold standard on approvals.
“Chronic ITP is challenging to treat because the heterogeneity of the disease makes it difficult to predict how an individual patient will respond to available treatments and not all patients can find a treatment that works well for them,” said James Bussel, professor emeritus of pediatrics at Weill Cornell Medicine and the principal study investigator. “The FDA approval of fostamatinib arms physicians with a new treatment option, which works via a novel mechanism.”