It was an up-and-down session on Wall Street Monday, with stocks opening higher but falling in the morning. The Dow Jones Industrial Average (DJINDICES:^DJI) and the S&P 500 (SNPINDEX:^GSPC) posted modest losses in a low-volume session.

Today's stock market

Index Percentage Change Point Change
Dow (0.79%) (206.67)
S&P 500 (0.39%) (10.88)

Data source: Yahoo! Finance.

Retail stocks slumped, with the SPDR S&P Retail ETF (NYSEMKT:XRT) falling 1.9%. Homebuilders were bright spots in the market; the iShares US Home Construction ETF (NYSEMKT:ITB) rose 1.3%.

As for individual stocks, Biogen (NASDAQ:BIIB) announced it's buying Nightstar Therapeutics (NASDAQ:NITE), and Village Farms International (NASDAQ:VFF) is launching an effort to enter the U.S. hemp market.

Downward stock graph and 1s and 0s

Image source: Getty Images.

Biogen pays up for gene therapy

Biogen is the latest biotech company to pursue gene therapy technology, snapping up U.K.-based Nightstar Therapeutics in an all-cash deal worth $800 million. Biogen will pay $25.50 for each Nightstar share, a 68% premium to Friday's closing price. Shares of Nightstar soared 66.1% and those of Biogen fell 2.1% on the news.

Nightstar's lead asset is a gene therapy treatment for choroideremia, a rare inherited retinal disorder that results in blindness and has no approved treatments. Results from a late-stage study of the therapy are expected in late 2020. The company also has earlier clinical testing underway for a treatment for X-linked retinitis pigmentosa, another rare disease that causes blindness.

The merger is the latest good news for gene therapy stocks, following last week's $4.8 billion deal by Roche to buy Spark Therapeutics, and last year's $8.7 billion purchase of AveXis by Novartis. Investors bid up other stocks in the space, speculating on what could be the next buyout target.

Check out the latest earnings call transcript for Biogen.

Village Farms joins the stampede into U.S. hemp

Canadian marijuana producer Village Farms International announced on Friday that it is teaming up with private U.S. company Nature Crisp for outdoor production of hemp and extraction of cannabidiol (CBD) oil. Shares initially jumped 12% on the news, but investors haven't been able to trade the recently listed stock since late Friday, after Nasdaq halted trading due to what the company called a "trading settlement mechanical matter."

The two companies have formed a joint venture called Village Fields Hemp, with 65% ownership by Village Farms, which will contribute $15 million in start-up costs. Investors know little about Nature Crisp, as its website has been taken down, but the press release says that parent company Jennings Group is a "pioneer in hemp cultivation," and that the joint venture will have 500 to 1,000 acres in hemp production this spring and oil extraction capabilities by the end of 2019.

Village Farms also hopes laws in Texas are changed to allow it to convert its greenhouses in that state from tomato to hemp production. If all of those were converted, they would make up the largest greenhouse hemp production footprint in North America.

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