Wall Street Today | US Stocks End Weekly Winning Streak

The $S&P 500 Index(.SPX.US)$ rose 0.2% to close at 4,697.24 Friday, while the $Nasdaq Composite Index(.IXIC.US)$ rose less than 0.1% to 14,524.07. The $Dow Jones Industrial Average(.DJI.US)$ was up 0.07%, to 37,466.11.

$Apple(AAPL.US)$ shed 5.9% this week after two analysts downgraded their ratings on the stock. The slump in the valuation of the company with the biggest market cap, weighed down the major indices.

Shares of $Palantir(PLTR.US)$, a data analytics company, traded lower on Friday after Barron's reported that Jefferies analyst Brent Thilla downgraded the stock to Underperform from Neutral. The analyst also cut the price target on the stock to $13 from $18, suggesting a 20% downside from current levels, according to Barron's.

$Applied Therapeutics(APLT.US)$ shares tanked 41% after the clinical-stage biopharmaceutical company said a Phase 3 study showed that the difference in results between patients treated with its AT-001 treatment for diabetic cardiomyopathy and those that got the placebo was "not statistically significant. "

$Omega Therapeutics(OMGA.US)$ tumbled 17%, giving back some of its meteoric gains on Thursday that were driven by optimism over the clinical-stage biotechnology company's research collaboration pact with Novo Nordisk. Omega shares almost doubled Thursday after the company said its flagship’s Pioneering Medicines initiative, and Novo Nordisk will jointly advance an obesity management program through preclinical development and conduct foundational activities.

$Wheels Up Experience(UP.US)$ shares climbed 17% in another volatile day as the provider of on-demand private aviation in the U.S. attempts to recoup losses posted in the past few days. On Dec. 27, the stock lost about 30% to $4.02 as trading volume shrank toward the end of the year. While it has risen for a fourth straight day, it hasn't recouped the amount it lost on the second trading day after Christmas.