What happened

Shares of BeiGene (BGNE 6.00%), a biopharmaceutical company with a presence in the U.S. and China, are jumping in response to a new partnership with one of the world's largest biotech companies, Amgen (AMGN 0.76%). Investors looking forward to the deal have driven this Chinese biotech's stock price 34.1% higher as of 11:38 a.m. on Friday.

So what

While most of us were perfecting our Halloween costumes, executives at Amgen and BeiGene were busy hammering out details of a deal that could prove incredibly important for both companies. Amgen will spend $2.7 billion on a 20.5% stake in BeiGene at $174.85 per share, which was a 36% premium to the stock's average price over the past 30 days.

Upward-sloping chart drawn with chalk.

Image source: Getty Images.

In return, BeiGene will commercialize two of Amgen's cancer therapies, Kyprolis and Blincyto, plus the bone-density drug Xgeva. A couple of years ago, BeiGene began marketing three of Celgene's drugs -- Revlimid, Abraxane, and Vidaza -- in China. In the first half of 2019, BeiGene's share of the revenue from these three products reached $115.6 million, an 85% increase over the previous-year period.

Amgen agreed to more than just a marketing arrangement. BeiGene will also handle the Chinese side of development efforts for 20 cancer-related assets in Amgen's pipeline. BeiGene will also be responsible for commercializing these drugs in China if they earn approval.

Now what

Combined global sales of the three cancer drugs that BeiGene will commercialize for Amgen reached an annualized run rate of $3.3 billion in the third quarter, but investors probably shouldn't expect these drugs to generate nine-figure sales right away in China. Xgeva launched in China in September, but Kyprolis and Blincyto are still in phase 3 trials.

If approved as expected, BeiGene-generated sales of Amgen's treatments probably won't rise as far as sales of Celgene's. Global sales of Revlimid alone reached an annualized $11.1 billion run rate in the third quarter.

Investors probably don't need to worry about BeiGene's cash burn rate. Although operating expenses are rising, product sales and collaboration revenue have been rising even faster. The company finished June with around $1.5 billion in cash and securities, and another $2.7 billion from Amgen will go a long way.