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What happened

Investors in Array Biopharma (ARRY) are having a great start to the trading week. Shares of the clinical-stage biotech are up more than 55% as of 11:30 a.m. EDT Monday in response to reporting positive clinical data from a phase 3 trial.

So what

Array and its partner Pierre Fabre released top-line results from Part 1 of their two-part phase 3 COLUMBUS trial on Monday. This trial was evaluating two of Array's experimental compounds -- encorafenib and binimetinib -- as a combination therapy in treating patients with BRAF-mutant advanced, unresectable, or metastatic melanoma, which is a deadly form of skin cancer.

The data showed that the combination therapy significantly improved progression-free survival (PFS) when compared to using Roche's Zelboraf (vemurafenib) alone. Specifically, the combination of encorafenib plus binimetinib demonstrated a PFS of 14.9 months, which was far ahead of the 7.3 months showed in patients who only received Zelboraf. In addition, the combination therapy was generally well-tolerated and adverse events were consistent with previous studies.

On the downside, Array came up a bit short in its attempts to hit the study's secondary endpoint. The goal was to compare the PFS of patients treated with the combination therapy to just using encorafenib as a monotherapy. While the combination demonstrated a median PFS of 14.9 months versus only 9.6 months using encorafenib as a monotherapy, its p-value of 0.051 was slightly above of the 0.05 that is required to prove statistical significance.

Still, that's a relatively small miss, and since the combination therapy had no problem meeting the study's primary endpoint traders are happily bidding up the share price on Monday.

Now what

More than 76,000 new cases of BRAF-Mutant Melanoma are recorded ever year in the U.S., and more than 10,000 patients are expected to die from this awful diseases. That represents a large unmet medical need, so bringing a new therapy to market that could extend those patient's lives may turn into a blockbuster.

Data from Part 2 of the COLUMBUS trials is expected to be available by the middle of 2017. If that data looks good then Array plans on moving forward with the regulatory approval process soon after.

All in all, this report was filled with good news, so it is easy to understand why shares are gaining ground on Monday.