Shares of Mylan NV (MYL) - Get Report were down 1.13% to $31.43 in midday trading on Wednesday, Aug. 9, after the company reported second-quarter results and reduced its expected performance for the rest of the year.

Mylan reported adjusted diluted earnings per ordinary share of $1.10, down 5% from the year-ago period. Revenue rose 16% year-over-year to $2.96 billion.

Analysts had forecast, on average, non-GAAP EPS of $1.16 on revenue of $3.02 billion, according to FactSet Research Systems.

"Given the region's ongoing challenges and the uncertain U.S. regulatory environment, we have elected to defer all major U.S. launches from our full year 2017 financial guidance to 2018, including generic Advair and generic Copaxone," said Mylan CEO Heather Bresch in a statement. "As a result, we now expect to deliver total revenues this year of between $11.5 billion and $12.5 billion, and adjusted EPS of between $4.30 and $4.70."

Previously, Mylan expected 2017 revenue to be in the range of $12.25 billion to $13.75 billion and adjusted EPS to be in the range of $5.15 to $5.55.

Meanwhile, shares of Achillion Pharmaceuticals Inc. (ACHN) - Get Report rose 21% to $4.86. The New Haven, Conn.-based firm reported second-quarter results and discussed interim results from a Phase 2 study of ACH-4471 for patients with untreated paroxysmal nocturnal hemoglobinuria.

Achillion had a  net loss of $22.5 million or $0.16 per share, compared with a net loss of $18.5 million, or $0.14 a share, in the year-ago period.

"Our focus in early clinical development with ACH-4471 has been on achieving proof-of-concept via factor D inhibition, and we are pleased to report that we believe we have achieved this goal," said  Achillion president and CEO Milind S. Deshpande in a statement. "The emerging interim results from our phase 2 PNH trial have demonstrated a dose response to treatment with what we believe to be meaningful improvements in LDH, hemoglobin, fatigue score and other markers of response."

Other biotech movers include  Cempra Inc. (CEMP) , whose shares rose 1.32% to $3.85 on the heels of its merger agreement with privately held Melinta Therapeutics.

"The combined company's extensive pipeline, including commercial, clinical and preclinical stage anti-infective programs with multiple products in development across several indications, provides an exceptional platform to deliver potential long-term growth and value for shareholders," said Cempra acting CEO David Zaccardelli in a statement.

Current Cempra stockholders will own about 48% and current Melinta shareholders will own about 52% of the combined firm, which will take the Melinta Therapeutics name.

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