SAM - Hot Stocks: OTIS SAM fall on downgrades; CTMX plunges on clinical data; SPCE rockets

Analyst comments provided a significant catalyst for midday trading on Thursday. Otis Worldwide ( NYSE: OTIS ) and Boston Beer ( SAM ) both lost ground on separate downgrades.

Elsewhere in the market, CytomX Therapeutics ( CTMX ) shed almost a third of its value following the release of clinical trial results for a potential breast cancer treatment.

On the other side of the spectrum, Virgin Galactic ( SPCE ) rocketed after announcing a deal with a division of Boeing ( BA ).

Decliners

Otis Worldwide ( OTIS ) showed midday weakness after an analyst removed their bullish stance on the elevator maker. Citing valuation concerns, JP Morgan lowered its rating on the stock to Neutral from Overweight .

The firm said many of the upside arguments for OTIS have already been priced into the stock. Following the downgrade, shares retreated 2% in intraday action.

A downgrade also put pressure on Boston Beer ( SAM ). Shares of the beer maker slipped more than 1% after RBC cut its rating to Sector Perform from Outperform .

Spotlighting long-standing woes in the firm's hard seltzer category, RBC said the stock has had trouble finding a bottom. As a result, analyst Nik Modi said it was time to "sit on the sidelines" until volume trends improve.

In other news, CytomX Therapeutics ( CTMX ) plunged 32% following the release of clinical trial results . While the company's investigative breast cancer drug met the primary endpoint, one arm of the study showed an overall response rate of less than 10%.

Gainer

Virgin Galactic ( SPCE ) received a major boost after it announced a contract for new spacecraft from a division of Boeing ( BA ). Shares jumped 12% after the space tourism company revealed a deal for BA division Aurora Flight Sciences to design and make next-generation motherships.

The tie-up calls for the delivery of two vehicles, which are each designed to handle up to 200 launches per year. The first delivery is slated to enter service in 2025.

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