Rigel Pharmaceuticals, Inc. announced that the U.S. Food and Drug Administration (FDA) has conditionally accepted the proprietary name Tavalisse™ for the company's investigational product candidate, fostamatinib disodium, an oral spleen tyrosine kinase (SYK) inhibitor. In addition, Rigel has applied to the U.S. Patent and Trademark Office to obtain federal registration of the Tavalisse mark. The name Tavalisse (pronounced - ta vah lees') was developed based on the FDA's Guidance for Industry, Contents of a Complete Submission for the Evaluation of Proprietary Names. Created with the help of experts in this field, the proprietary name development included input from prescribers, pharmacists, linguists and employees to create a unique and approachable name. Earlier this month, the company announced that it submitted a New Drug Application (NDA) to the FDA for Tavalisse in patients with chronic and persistent immune thrombocytopenia (ITP). The FDA previously granted Orphan Drug designation to Tavalisse for the treatment of patients with ITP. The NDA is supported by data from the Phase 3 clinical program for Tavalisse in ITP, which was comprised of three studies, two randomized placebo-controlled studies (Studies 047 and 048) and an open-label extension study (Study 049). In total, 163 ITP patients have been treated with Tavalisse and included in the NDA submission. Across all indications, Tavalisse has been evaluated in over 4,600 subjects.