Rhizen Pharmaceuticals and TG Therapeutics Sign Joint Venture Collaboration Agreement

Rhizen Pharmaceuticals and TG Therapeutics Sign Joint Venture Collaboration Agreement for Worldwide Development and Commercialization of Novel Selective PI3Kδ Kinase Inhibitors - IND Filing Expected Fourth Quarter 2012 - Collaboration and Licensing Payments Could Exceed $250MM La Chaux-de-Fonds, Switzerland (August 16, 2012)-- Rhizen Pharmaceuticals (Rhizen), a biopharmaceutical company focused on the discovery and development of novel therapeutics for the treatment of cancer, inflammation, autoimmune diseases and metabolic disorders, and TG Therapeutics (OTCC: TGTX, TG), focused on developing and commercializing therapeutic products for cancer, today announced a Joint Venture Collaboration for global development and commercialization of Rhizen’s Novel Selective PI3Kδ Kinase Inhibitors. The selected lead RP5264 (hereafter, to be developed as TGR-1202) is an orally available, small molecule, PI3Kδ specific inhibitor currently being positioned for the treatment of haematological malignancies. Beyond RP5264, Rhizen would contribute backup molecules providing multiple opportunities for TG to develop differentiated therapies against haematological cancers and autoimmune diseases while, retaining joint governance role in the JV. Under the terms of the current JV agreement, TG will pay Rhizen an execution fee and predetermined milestone payments linked to clinical development of products till Phase II. The JV has a built-in option for both TG and Rhizen to convert into a licensing agreement during development whereby, TG would in-licence and assume entire responsibility for developing and commercializing RP5264 globally. Rhizen would then be entitled to an up-front payment and other milestone payments of circa $250M plus royalties and profits on sublicensing. In addition, Rhizen retains global manufacturing and supply rights for API and formulation for clinical and commercial purposes. About PI3K and RP5264 The phosphoinositide-3-kinases (PI3Ks) are a family of enzymes involved in cellular functions, including cell proliferation and survival, cell differentiation, intracellular trafficking and immunity. The delta isoform of PI3K is strongly implicated in B-cell related lymphomas. Rhizen has developed novel selective inhibitors of PI3Kδ pathway, believed to be important in the proliferation and survival of B-cell lymphocytes. The lead candidate RP5264 has demonstrated activity in preclinical xenograft models and primary cells from patients for haematological cancers. About Rhizen Pharmaceuticals Rhizen is a biopharmaceutical company dedicated to the discovery and development of novel therapeutics to treat cancer and immune disorders. Rhizen has to date created a diverse portfolio of proprietary drug candidates targeting several cancers and immune associated cellular pathways. Rhizen Pharmaceuticals is a privately held company founded in 2008 and headquartered in La Chaux-de-fonds, Switzerland. (www.rhizen.com) Contact: Haripriya Addepalli Email: [email protected] About TG Therapeutics, Inc. TG Therapeutics is an innovative, clinical-stage biopharmaceutical company focused on the acquisition, development and commercialization of innovative and medically important pharmaceutical products for the treatment of cancer and other underserved therapeutic needs. Currently TG is developing Ublituximab (TGTX-1101), a novel, third generation monoclonal antibody that targets a specific and unique epitope on the CD20 antigen found on mature B-lymphocytes. (www.tgtxinc.com) Contact: Jenna Bosco Director – Investor Relations TG Therapeutics, Inc. Telephone: 212-554-4484 Email: [email protected]

Launch Readiness

Optimize cross-functional collaboration and engage with key stakeholders for the successful launch of a product

Join the Launch Readiness for Medical Affairs & Communications Teams Summit to learn best practices in taking a structured approach to enhance medical affairs activities surrounding a launch and increase knowledge and communication with thought leaders.