Image source: Exelixis.

What: Exelixis (NASDAQ:EXEL) is up 10% as we approach the closing bell today after the biotech and its partners presented data at the American Society of Clinical Oncology (ASCO) meeting over the weekend.

So what: The biotech had multiple presentations at ASCO, and it seems to be a combination of those data with perhaps some relief that nothing bad cropped up that has investors hitting the buy button.

One presentation covered the overall survival data for Cabometyx from the METEOR trial in renal cell carcinoma, the most common form of kidney cancer, in patients who had already failed one drug. Patients on Cabometyx lived for a median of 21.4 months versus 16.5 months for patients on Novartis' (NYSE:NVS) Afinitor, and Cabometyx reduced the risk of death by 34%. Those data were already known since it's on the FDA approved label, but there were additional data presented, including that Cabometyx appears to work as well no matter what first-line drug the patient had received, and that the survival difference wasn't affected by subsequent treatments after the patients failed Cabometyx or Afinitor.

In a subgroup analysis, Exelixis showed that Cabometyx seems to be helping patients whose kidney cancer has moved through the blood stream and started to grow on the bone or other internal organs. The overall survival for that group was 20.1 months for patients who received Cabometyx, versus 10.7 months for patients on Novartis' Afinitor.

While Cabometyx has quickly become Exelixis' prized possession, the biotech also has Cotellic, which it licensed to Genentech, which was bought by Roche. The drug was approved in combination with Roche's Zelboraf for melanoma patients in November, but that's a tough market with lots of competition, and investors are rightfully taking a wait-and-see attitude toward potential sales of Cotellic.

Fortunately, it appears Cotellic is working well in colon cancer patients, too. In combination with Roche's Tecentriq, the drugs produced an objective response rate of 17% of the 23 patients in the phase 1b trial, with four confirmed partial responses and five patients with stable disease. Not bad for patients with few options remaining.

Now what: Exelixis is rightfully flying high on data from ASCO, but now it has to execute on the sales side. Cabometyx will clearly take market share from Novartis, but so will Bristol-Myers Squibb, which has a drug, Opdivo, that also beat Afinitor. We'll get a first look at sales for Cabometyx when the company releases second-quarter earnings in a couple of months.

For Cotellic, the potential in colon cancer could help boost sales, but we'll have to wait for data from a recently started phase 3 trial before we know for sure.

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