Shares of Mylan N.V. sank 2.7% in morning trade toward a 7 1/2-year low, after Fitch Ratings revised its outlook on the generic drug maker's credit rating to negative from stable, putting the rating in danger of a downgrade to "junk" status. Mylan's long-term issuer default rating at Fitch is BBB-, the lowest investment-grade rating. Fitch said the revised outlook reflects its expectation that gross leverage may remain elevated over the near term because of slower-than-expected revenue growth, cash generation and debt reduction. Fitch's rating and outlook is similar to S&P Global Ratings' BBB- rating with a negative outlook, while Moody's Investors Service has a Baa3 rating--one notch above "junk"--with a stable outlook. Generic drug maker stocks have been under pressure in recent weeks, and took another header on Monday after more than 40 state attorneys general filed suit against 20 makers of generic medications, alleging a conspiracy to artificially inflate prices and reduce competition. Shares of fellow generic drug maker Teva Pharmaceutical Industries Ltd. slid 6.1% in morning trade to a 1 1/2-year low. Year to date, Mylan's stock has tumbled 27.6% and Teva shares have plunged 26.2%, while the SPDR Health Care Select Sector ETF has gained 1.3% and the S&P 500 has tacked on 13.3%.