By Ben Eisen

NEW YORK (MarketWatch) -- Shares of Tesla Motors Inc. rose in premarket trade Tuesday after the National Highway Traffic Safety Administration reaffirmed the car maker's five-star safety rating.

Gainers

Tesla's (TSLA) share price had been set back recently by reports of fires in the auto maker's electric vehicles. However, a federal review left the top safety rating intact. After the news, shares rose 2.8% in premarket trade on Tuesday.

Supernus Pharmaceuticals Inc. (SUPN) advanced 20% premarket after a drug that the company had worked on, called Orenitram, won approval from the Food and Drug Administration.

ImmunoCellular Therapeutics Ltd. (OPMO) surged 24% after the company reported encouraging results from tests of its cancer drug.

Decliners

CalAmp Corp. (CAMP) shares slid 8.4% after the maker of wireless and satellite communications technology gave an outlook below market expectations. CalAmp said it expects to earn between 19 and 23 cents per share in the current quarter, while Wall Street analysts had expected 24 cents per share, according to a Thomson Reuters survey. Nonetheless, last quarter's profit edged up 1.3%.

Trending tickers

Twitter Inc. (TWTR) shares rose 1.5% premarket, a day after gaining 7.6%.

Wunderlich Securities Analyst Blake Harper wrote about Twitter on Tuesday: "While the company is growing revenues faster than its fastest growing peers and we do recognize the potential for the company to capture larger portions of the mobile and TV advertising market, it appears valuation metrics are irrelevant and that investors are betting aggressively on Twitter being the next great media-technology platform."

The Walt Disney Co. (DIS) was down 0.1% in thin trading after one of Twitter's founders, Jack Dorsey, was elected to the Disney board.

Facebook Inc. (FB) shares were up 0.5% premarket. The Internet company gained 4.8% Monday on its first day of trading in the S&P 500 index (SPX).

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