Usually cancer drugs go after patients with no other options first before moving on to a first-line indication, so it's curious that Pfizer's (NYSE: PFE ) Torisel, which is approved as a first-line treatment for kidney cancer patients, was being tested as a second-line treatment. Even more curious is that it failed the phase 3 trial.
Of course, like most things in drug development, this isn't that clear-cut. Torisel is approved as a first-line treatment, but only for patients who have at least three of six prognostic risk factors. Wyeth, which Pfizer bought, went after the in-need group first.
Pfizer's Sutent is also approved as first-line treatment without the need for the poor prognosis, but some 40% to 65% of kidney cancer patients require another treatment. In the trial released yesterday, Pfizer was trying to capture those patients by testing the drug in patients who had failed Sutent.
The trial failed, but it's important to point out that the negative result doesn't mean that Torisel doesn't work in these second-line patients. Rather, the data just says that Torisel isn't any better than Bayer and Onyx Pharmaceuticals' (Nasdaq: ONXX ) Nexavar, which it was being compared to. There's even a possibility that it might even be better; Pfizer said the delay before the tumor started growing again was longer for the Torisel-treated patients, but the difference wasn't statistically significant.
The data will be presented at an upcoming medical meeting, where we'll get to put some numbers with the top-line result, but it really doesn't matter all that much. The marginal difference will make it hard to justify running another larger trial to show a statistically significant difference. Pfizer would be better off putting the second-line indication on the shelf, especially after AVEO Pharmaceuticals' (Nasdaq: AVEO ) tivozanib beat Nexavar in a head-to-head trial in kidney cancer patients.
The kidney cancer market is fairly crowded; Roche's Avastin, GlaxoSmithKline's (NYSE: GSK ) Votrient, and Novartis' (NYSE: NVS ) Afinitor are all approved to treat the cancer at varying stages. Add in Pfizer's recent approval of its third kidney cancer drug, Inlyta, and there's a whopping seven drugs approved with tivozanib potentially making it eight.
Finding a niche for Torisel beyond poor-prognosis patients would help increase sales, but it doesn't look like a second-line indication is it.