Shares of Express Scripts (ESRX) are dropping near noon following comments from its CEO Tim Wentworth, who said he believes scrutiny into drug pricing "is not going to go way." The company also announced updated guidance for 2016 and 2017.

TRUMP IMPACT: During Express Scripts' 2017 financial guidance conference call, CEO Tim Wentworth signaled that scrutiny into drug pricing will continue. "There's no question in my mind that the conversation is not going to go away, and we have to demonstrate, by using both our tools and our clients' voices as well, that there are solutions out there that can be very workable," he said. Nonetheless, commenting on the potential impact of the Trump administration, Wentworth noted that "It's so early... I've not seen anything that causes me to be hugely concerned." Additionally, the company's top executive noted that drug price inflation will unlikely represent a "significant headwind" in 2017.

CITRON CAUTIOUS COMMENTS: Last week, Andrew Left's Citron Research posted cautious comments on Twitter, comparing the pharmacy benefit manager to Philidor, the specialty pharmacy at the center a scandal involving Valeant Pharmaceuticals (VRX). Speaking in a CNBC interview, Citron's Left said he is "simply connecting some dots" after Donald Trump's interview in Time magazine, where the President-elect reiterated that he wants to "bring down drug prices." Left reiterated that Express Scripts and other pharmacy benefit managers are keeping drug prices high: "It is about rebates. It is amazing how many different hands a drug has to touch before it gets used."

GUIDANCE: Earlier today, Express Scripts reaffirmed its previously issued 2016 full year adjusted earnings per share guidance of $6.36 to $6.42 per share, with consensus at $6.39. Additionally, the company said it sees 2017 adjusted earnings per share of $6.82-$7.02, with consensus at $6.93. Express Scripts also announced that it is revising its methodology for reporting network claims for its 2017 financial guidance and for reporting periods beginning with the year ending December 31, 2016. Following the announcement, William Blair analyst John Kreger told investors in a research note that he sees Express Scripts' initial 2017 guidance as generally in-line with market expectations and "slightly above" his own forecast. Nonetheless, the analyst noted that he would prefer to see a return of claims growth, rather than reliance on better profitability per claim and buybacks to drive the high-single-digit earnings per share growth. The analyst, citing the stock's low valuation, reiterated an Outperform rating on Express Scripts.

PRICE ACTION: Near noon, shares of Express Scripts have dropped nearly 5% to $69.79. CVS Health (CVS), which also operates a pharmacy benefit management business, is down 0.4% to $79.81.