Concerns about the effect of the trade war on the economy deepened Tuesday after new tariffs went in place over the weekend and a report showed that U.S. factory activity in August contracted for the first time in three years. The Dow Jones Industrial Average (DJINDICES:^DJI) and the S&P 500 (SNPINDEX:^GSPC) both fell, with trade-sensitive industrial and technology stocks taking the biggest hits.

Today's stock market

Index Percentage Change Point Change
Dow (1.08%) (285.26)
S&P 500 (0.69%) (20.19)

Data source: Yahoo! Finance.

As for individual stocks, shares of Medicines Company (NASDAQ:MDCO) rose on news of a successful drug trial and those of Boston Beer (NYSE:SAM) declined in the wake of an analyst downgrade.

Falling graph, columns of numbers, coins, and a skyline.

Image source: Getty Images.

New cholesterol drug boosts Medicines Company

Medicines Company presented details of a successful pivotal clinical trial of inclisiran, the biopharma's new cholesterol-lowering drug, and shares added to recent gains, popping 10.4%. On average, the 1,617 patients in the study, nearly all of which were already taking statins, achieved a 54% reduction in LDL-C at day 510 of the study and a time-averaged 50% reduction from days 90 through 540.

Inclisiran is the first of a new class of drugs called small-interfering RNA, and has the advantage over existing cholesterol-lowering drugs of being administered as an injection only twice a year. The company is conducting two other phase 3 trials that are expected to read out in the third quarter, followed by U.S. regulatory submission in Q4.

Shares of Medicines Company jumped 14% last week when the pharmaceutical company announced that the trial was a success, and investors added to those gains and boosted shares of partner Alnylam Pharmaceuticals after hearing new details today.

Boston Beer faces competition in hard seltzer, but is cannabis next?

Shares of Boston Beer Company fell 6.2% to $411.10 after an analyst downgraded the stock on concerns about competition in the hard seltzer category. Kevin Grundy of Jeffries downgraded Boston Beer from hold to underperform and lowered his target price from $360 to $332. Grundy cited a Jeffries consumer survey that indicated that seltzer drinkers have low brand loyalty and that Boston Beer's Truly brand is mentioned in only 3% of social media posts about hard seltzer.

The craft beer category has changed a lot recently, turning into more of a local phenomenon, with 1,000 new breweries popping up every year. Boston Beer has become more dependent on the hard seltzer category to keep up its double-digit growth. The company has been very successful with this strategy to this point, saying in its most recent conference call that growth of almost 17% was largely because of Truly and Twisted Tea brands.

In an interview with CNBC on Friday, CEO David Burwick noted that while the company is investing heavily in hard seltzer, it's watching developments in cannabis drinks closely, and said Boston Beer will "play ... some point down the road" in the category after it develops.

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