US stock indexes drift higher in afternoon trading

Stocks moved slightly higher in afternoon trading Monday, on pace to build modestly on gains from last week. The market has closed higher over the past three trading days. Discouraging data on U.S. home sales and a deepening slide in oil prices held back the rally.

KEEPING SCORE: The Dow Jones industrial average rose 103 points, or 0.5 percent, to 17,908 as of 1:14 p.m. Eastern time. The Standard & Poor’s 500 index gained two points at 2,072. The Nasdaq composite added 11 points, or 0.2 percent, to 4,776.

SANTA RALLY: Stocks are continuing a pre-Christmas advance, which traders often refer to as a “Santa” rally. Major indexes ended last week on a strong note, finishing higher three days in a row. The Dow and S&P 500 are both up for the month, while the Nasdaq is down.

THE QUOTE: “With the Dow being up substantially more than the S&P 500, I would tend to say what’s holding back the S&P is more related to its makeup than it is a problem related to investors’ perception or concerns,” said Sam Stovall, U.S. equity strategist at S&P Capital IQ. “We’re firmly in a Santa Claus rally.”

SECTOR WATCH: Six of the 10 sectors in the S&P 500 index rose, led by technology stocks. Energy stocks declined. The sector is down about 10 percent this year.

PROMISING PHARMA: Achillion Pharmaceuticals’ shares gained 13.5 percent after the biotechnology company reported positive results from two studies focusing on a treatment regimen for hepatitis C patients. The stock rose $1.94 to $16.15. Meanwhile, Enanta Pharmaceuticals vaulted 9 percent after it received regulatory approval for a hepatitis C treatment. Enanta added $3.53 to $50.15.

TASE ME, BRO: Electronic weapons and body camera maker Taser International says it received nearly 1,900 product orders and expects to ship during the fourth quarter. The stock surged $2.17, or 9 percent, to $26.15.

SHELL GAME: Shares in Caesar’s Entertainment jumped 15 percent on news the casino operator will buy an affiliate in a bid to smooth the reorganization of another struggling division and balance its debt load. The stock gained $2.02 to $15.51.

HOUSING SPUTTERS: The National Association of Realtors reported that sales of previously occupied homes fell 6.1 percent last month to a seasonally adjusted annual rate of 4.93 million. That’s the slowest pace in six months. Over the past 12 months, sales have risen 2.1 percent. The disappointing data initially sent shares in most homebuilders lower. The sector bounced back by afternoon, led by William Lyon Homes. The stock added 61 cents, or 3.3 percent, to $19.47.

PUSHING BACK: Shares in drugmaker Gilead Sciences fell 12 percent after pharmacy benefits manager Express Scripts said it will no longer cover two of Gilead’s hepatitis C drugs as part of an effort to battle the high cost of treatment for the disease. Gilead slid $35.06 to $95.39.

PAID OUT: Ocwen Financial slid 27.4 percent on news that the subprime mortgage servicer’s executive chairman will resign in a settlement that also provides $150 million to homeowners. The stock shed $6.01 to $15.89.

EYE ON OIL: Benchmark U.S. crude fell $1.76, or 3.1 percent, to $55.38 a barrel. Oil peaked at $107 a barrel in June but has plunged since then due to weak demand and abundant supplies, especially after Saudi Arabia and other OPEC members agreed to maintain production levels.

ENERGY SLUMP: Several oil production and exploration companies tumbled as the slide in oil prices deepened. Nabors Industries fell 71 cents, or 5.2 percent, to $12.92, while Chesapeake Energy slid $1.26, or 6.3 percent, to $18.60. Range Resources shed $2.90, or 4.8 percent, to $56.97. Southwestern Energy dropped $1.78, or 5.7 percent, to $29.22.

EUROPEAN MARKETS: Britain’s FTSE 100 rose 0.5 percent, while Germany’s DAX rose 0.8 percent. France’s CAC 40 gained 0.3 percent.

BONDS: U.S. government bond prices fell. The yield on the 10-year Treasury note rose to 2.18 percent from 2.17 percent late Friday.