Arena inks deal with Aristea for RIST4721 and acquisition option

US companies Arena Pharmaceuticals (Nasdaq: ARNA) and Aristea Therapeutics have entered into a strategic collaboration to advance the clinical development of RIST4721, an oral CXCR2 antagonist being developed by Aristea for the treatment of palmoplantar pustulosis (PPP) and other neutrophil-mediated diseases. Arena’s shares closed down nearly 4% at $61.32 on the news yesterday.

Under the terms of the accord, Arena will provide a $60 million upfront payment to Aristea and a $10 million equity investment in Aristea’s Series B financing. In return, Aristea has granted Arena an exclusive option to acquire Aristea, including rights to all CXCR2 programs, on completion of the Phase IIb study of RIST4721 in PPP.

The agreement also provides a framework during the option period for the companies to jointly explore the development of additional neutrophil-mediated diseases, including hidradenitis suppurativa (HS) and inflammatory bowel disease (IBD), potentially generating multiple data readouts during the option period.