Shares of Rigel Pharmaceuticals, Inc. (RIGL) jumped as much as 39% to $3.53 in Monday’s session on hefty volume of 8.80 million shares 28X its average volume.

Bristol-Myers Squibb (BMY) enters into a collaboration agreement with Rigal Pharmaceuticals (NASDAQ:RIGL) to discover, develop and commercialize cancer immunotherapies based on Rigal's small molecule TGF beta receptor kinase inhibitors.

The partnership will focus on developing immunotherapeutics as monotherapy or in combination with immune checkpoint inhibitors, including BMY's Opdivo (nivolumab) and Yervoy (ipilimumab). Under the terms of the agreement, BMY will have global rights to develop and commercialize small molecule therapeutics derived from Rigal's TGF beta library, including, but not limited to, those approved to treat cancer.

 Rigal will receive an upfront payment of $30M, potential milestones of more than $309M for a successful compound that is cleared for multiple indications and tiered royalties on net sales. Transforming growth factor (TGF) beta is a secreted protein that controls proliferation, differentiation and other functions in most cells. In the immune system, it plays an immunosuppressive role which can significantly dampen anti-tumor immune responses.

Rigel Pharmaceuticals, Inc. is a clinical-stage drug development company. The Company discovers and develops small-molecule drugs for the treatment of inflammatory and autoimmune diseases, as well as muscle disorders. Its research focuses on intracellular signaling pathways and related targets that are critical to disease mechanisms. The Company has five product candidates in development: fostamatinib, an oral spleen tyrosine kinase (SYK) inhibitor expected to enter Phase 3 clinical trials for immune thrombocytopenic purpura (ITP) and a Phase 2 clinical trial for immunoglobulin A nephropathy (IgAN) in the first half of 2014.