Pre-Open Stock Movers:

Casa Systems, Inc. (Nasdaq: CASA) 47% HIGHER; awarded a multi-year purchase contract from Verizon (NYSE: VZ) and Verizon will take a 9.9% stake.

TG Therapeutics, Inc. (NASDAQ: TGTX) 33% LOWER; has voluntarily withdrawn the pending Biologics License Application (BLA)/supplemental New Drug Application (sNDA) for the combination of ublituximab and UKONIQ® (umbralisib) (combination referred to as U2) for the treatment of adult patients with chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL).

Nektar Therapeutics (NASDAQ: NKTR) 31% LOWER; The company and Bristol Myers Squibb (NYSE: BMY) ended the global clinical development program for bempegaldesleukin in combination with Opdivo after late-stage trials failed to yield results.

Natus Medical Incorporated (NASDAQ: NTUS) 28% HIGHER; to be acquired by an affiliate of ArchiMed for $33.50 in cash.

BitNile Holdings, Inc. (NYSE: NILE) 19% HIGHER: Revenue of $52.4 million, an increase of 120% from $23.9 million in the prior fiscal year.

Twitter, Inc. (NYSE: TWTR) 3% HIGHER; adopts a poison bill following Elon Musk's bid, other suitors could be interested.

Southwest Gas Holdings, Inc. (NYSE: SWX) 3% HIGHER; to explore strategic alternatives following an indication of interest well in excess of Carl Icahn's $82.50 per share offer.

Wendy's (NASDAQ: WEN) 2% LOWER; BMO Capital downgraded from Outperform to Market Perform with a price target of $22.00 (from $28.00).

Sirius XM Radio (NASDAQ: SIRI) 2% LOWER; Morgan Stanley downgraded to Underweight

Gap (NYSE: GPS) 2% HIGHER; Morgan Stanley upgrades to Equal Weight, saying headwinds are mostly priced in.

Synchrony Financial (NYSE: SYF) 2% HIGHER; reported Q1 EPS of $1.77, $0.23 better than the analyst estimate of $1.54. Raises dividend and buyback.

Mullen Automotive, Inc. (NASDAQ: MULN) 1% HIGHER; to start EV battery pack production out of its high voltage battery R&D facility located in Monrovia, California.