On July 27, 2021, Arena Pharmaceuticals, Inc. and Aristea Therapeutics, Inc. announced a strategic collaboration to advance the clinical development of RIST4721, an oral CXCR2 antagonist being developed for the treatment of palmoplantar pustulosis (PPP) and other neutrophil-mediated diseases. Wilson Sonsini advised Aristea Therapeutics on the transaction.

According the press release, Arena will provide a $60 million upfront payment to Aristea and a $10 million equity investment in Aristea’s Series B financing. Aristea also has granted Arena an exclusive option to acquire Aristea, including all rights to CXCR2 programs, upon completion of the Phase 2b study of RIST4721 in PPP.

In addition, Aristea announced separately the closing of a $63 million Series B financing led by Fidelity Management & Research Company, LLC. Existing investor Novo Holdings A/S and new investors Arena Pharmaceuticals also participated, with funds managed by Tekla Capital Management LLC.

The Wilson Sonsini team advising Aristea Therapeutics on the transaction includes the following attorneys:

Technology Transactions
Miranda Biven, Partner
Colin Bosch, Associate
Sai Upadhyayula, Associate

Corporate
Dan Koeppen, Partner
Jason Skolnik, Partner
Meghan Burton, Associate
Daniel Canavan, Associate
Kexi Wang, Associate

IP - Patents and Innovations
Michael Hostetler, Partner
Ingo Hardt, Associate

Regulatory
David Hoffmeister, Partner
Eva Yin, Associate

Employee Benefits and Compensation
Scott McCall, Partner
Michael Klippert, Associate

Antitrust
Baasil Shariff, Associate

Tax
Jonathan Zhu, Partner
Derek Wallace, Partner
Nika Antonikova, Associate

Please see the related press release for more information.