NEW YORK (

TheStreet

) -- Shares of health care companies

Express Scripts

(ESRX)

,

Medco Health Solutions

(MHS)

and

Watson Pharmaceuticals

(WPI)

were among the best performers on the

S&P 500

midday Tuesday.

The index dropped 5.64 points to 1,346.17 midday Tuesday.

Shares of Express Scripts rose 2.73% to $51.15. The pharmacy benefit manager, which has been trying to merge with Medco Health Solutions, another PBM, since the two signed a definitive merger agreement in July, presented more information to American antitrust regulators recently, according to

Reuters

. The $29 billion deal has received significant antitrust scrutiny.

Express Scripts has an estimated price-to-earnings ratio for next year of 14.08; the average for health care providers is 20.90. For comparison, Medco,

WellPoint

(WLP)

and

Aetna

(AET)

all have lower forward P/Es of 13.83, 7.69 and 8.34, respectively.

Twenty-two of the 25 analysts who cover Express Scripts rated it a buy. Three analysts gave it a hold rating.

TheStreet Ratings

gives Express Scripts a B grade with a buy rating and a

$58.07

price target. The stock has risen 14.3% year to date.

Medco shares increased 1.77% to $62.02.

Of the 23 analysts who cover Medco, 12 rated it a buy and 11 rated it a hold.

Medco gets a B grade from

TheStreet Ratings

and a

$69.87

price target. The stock has increased 10.88% year to date.

Shares of Watson Pharmaceuticals rose 2.77% to $59.31. The company on Tuesday reported fourth-quarter earnings of $94.8 million, or 75 cents a share, which rose from year-earlier earnings of $18.3 million, or 15 cents.

The pharmaceutical company said it expects 2012 earnings of between $5.50 and $5.80 a share. Analysts were anticipating $5.60 a share.

Watson has a forward P/E of 9.96; the average among pharmaceutical companies is 17.8. For comparison,

Perrigo

(PRGO) - Get Report

and

Salix Pharmaceuticals

(SLXP)

have forward P/Es of 9.77 and 18.47, respectively.

Sixteen of the 25 analysts who cover Watson rated it a buy. Nine analysts gave it a hold rating.

TheStreet Ratings

gives Watson a B+ grade with a buy rating and a

$76.45

price target. The stock has fallen 1.71% year to date.

-- Written by Alexandra Zendrian

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