We are investigating possible breaches of fiduciary duty and other violations of law by the board of directors of Sierra Oncology, Inc. (“Sierra” or the “Company”) (NASDAQ: SRRA), in connection with the proposed acquisition of the Company by GlaxoSmithKline plc (NYSE: GSK). Under the terms of the merger agreement, the Company’s shareholders will receive $55.00 in cash for each share of Sierra common stock owned.  The transaction is valued at approximately $1.9 billion.

Weiss Law is investigating whether (i) Sierra’s board of directors acted in the best interests of Company shareholders in agreeing to the proposed transaction, (ii) the $55.00 per-share merger consideration adequately compensates Sierra’s shareholders, and (iii) all information regarding the sales process and valuation of the transaction will be fully and fairly disclosed.