What happened

Clovis Oncology Inc. (NASDAQ:CLVS) stock soared 69.6% in June, according to data from S&P Global Market Intelligence. Clinical-trial results showed the company's lead drug Rubraca provided a significant long-term survival benefit.

So what 

Late last year, the Food and Drug Administration (FDA) granted Rubraca an accelerated approval for the treatment of a genetically defined group of ovarian-cancer patients, following treatment with two or more chemotherapies. The approval was based on the drug's ability to shrink tumors. Although the FDA is increasingly willing to speed potentially life-saving drugs to the market based on tumor shrinkage, such approvals are generally contingent upon their ability to prove a significant survival benefit over the long term.

Man pointing to stock chart on the rise.

Image source: Getty Images.

Rubraca is a member of a relatively new class of cancer therapies known as PARP inhibitors, and proof of a significant survival benefit should encourage more oncologists to add it to their treatment arsenals. The proof is pretty strong: According to an independent review, median progression-free survival among all patients treated with Rubraca was 13.7 months versus just 5.4 months among those given a placebo.

Now what

Clovis Oncology recorded just $7.0 million in Rubraca sales during its first full quarter post approval, and lost $58.5 million during the three-month period. Now that the company's sales force can tout compelling survival data, investors can reasonably expect a serious acceleration in sales of the drug and a less disturbing gap between sales and expenses this year.

Further ahead, the company intends to file another application to move Rubraca up a step in the ovarian-cancer treatment paradigm. At the moment, patients need to have been treated with two or more chemotherapies to become eligible for the drug.

A planned submission to expand its addressable patient population to patients with just one round of treatment could be a huge step on the company's path to profitability, if approved. Given the results announced last month, the company's chances of earning a label-expanding approval look pretty good.

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