Why Clovis Oncology Shares More Than Doubled

Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Clovis Oncology , a biopharmaceutical company that's developing anti-cancer therapies, vaulted higher by as much as 136% (that's not a typo!) after reporting positive data on two early stage experimental treatments -- CO-1686 in EGFR-mutant non-small cell lung cancer (NSCLC) and Rucaparib in a monotherapy study of solid tumors -- at the American Society of Clinical Oncology's annual meeting.

So what: In the 37 patient Rucaparib trial, 21 patients had breast cancer, 10 ovarian cancer, and six others had different types of solid tumors. The data showed that Rucaparib provided an 89% clinical benefit to patients with ovarian cancer. Clovis is still in the process of determining the recommended dosage but plans on initiating late-stage trials in the drug as soon as the second half of this year.

For CO-1686, Clovis noted that three of the four patients with the dominant resistance mutation T790M had achieved a partial response in phase 1 studies, although maximum tolerated dosing studies are still ongoing. Thus far, 42 patients have been enrolled, and the treatment appears to be well-tolerated.

Now what: While the data on Clovis' NSCLC drug is encouraging, today's move is all about the potential of Rucaparib -- especially with how effective it was in delivering a clinical benefit with regard to ovarian cancer. The drug is a PARP inhibitor with an affinity for being effective in patients with BRCA gene mutations and, assuming this data stays positive, could be in front of the FDA by as soon as the second half of 2014, by my best guess.

Personally, though, I think today's move is way overdone. Clovis' lead drug candidate in November was metastatic pancreatic cancer drug CO-101, and its development was halted following unsuccessful mid-stage trials. Clovis hasn't succeeding in bringing a drug to market yet, so it's burning cash and still has nothing more than a handful of early stage drug hopefuls to show for its now $2.1 billion valuation. If you've been lucky enough to catch a ride on this rocket, I would certainly suggest cashing in your chips and heading for the hills.

Craving more input? Start by adding Clovis Oncology to your free and personalized Watchlist so you can keep up on the latest news with the company.

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The article Why Clovis Oncology Shares More Than Doubled originally appeared on Fool.com.

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