San Diego, California, [May 3, 2022] – Plexium, Inc. (Plexium), a leading next-generation targeted protein degradation (TPD) company, today announced the appointment of Stephen Mullennix as Chief Financial Officer (CFO). Mr. Mullennix brings more than 20 years of financial and operational expertise in the biotechnology and private equity sectors to Plexium, with a strong background in developing and executing corporate and financial growth strategies.

“I am thrilled to welcome Stephen to Plexium as our Chief Financial Officer,” said Plexium President & CEO Percival Barretto-Ko. “Stephen’s extensive financial and operational leadership, coupled with his proven track record in creating long-term enterprise value, will strengthen our team as we grow into a premier, next-generation Targeted Protein Degradation company.  A seasoned CFO and leader, Stephen will undoubtedly contribute to Plexium’s aspirations to seek novel therapies to improve patients’ lives.”

Mr. Mullennix joins Plexium from ProSciento, Inc. where he served as Chief Financial Officer and played a critical role in advancing clinical methodologies for drugs and devices in the metabolic disease arena.  Prior to ProSciento, Mr. Mullennix was Chief Financial Officer and Chief Operating Officer of UroGen Pharma, Ltd (NYSE:URGN). During his tenure at UroGen, he helped the company build its management team and corporate infrastructure that successfully launched its first FDA-approved drug for urothelial cancer and progressed a pipeline of Uro-Oncology drug candidates. Before UroGen, Mr. Mullennix was Chief Financial Officer and Senior Vice President of Operations at SolarReserve, LLC, a solar energy technology company, where he supported the company’s global expansion and oversaw multiple corporate and project financings. Prior to SolarReserve, he served as a Managing Director at US Renewables Group, a private equity investment fund with more than $750 million of assets under management. Mr. Mullennix has been directly involved in $3.3 billion of public, private, equity, debt, and M&A transactions. He earned his MBA from the Anderson School at the University of California Los Angeles and BA in Economic Geography from Dartmouth College.

Mr. Mullennix commented, “Plexium’s best-in-class approach to identifying monovalent target protein degraders through its proprietary drug discovery platform is truly unique and unprecedented.  This has been recognized by top-tier investors and partners, as evidenced by the company’s recent $102 million Series B financing and partnerships with Amgen and AbbVie.  These advancements have created significant momentum in recent months, and I look forward to joining the team and contributing to the continued growth of Plexium.”

About Plexium

Plexium is the premier, next-generation Targeted Protein Degradation (TPD) company seeking to discover a wide range of monovalent target protein degraders that address the limitations of heterobifunctional degraders and cereblon IMiDs. The company is powered by its proprietary drug discovery platform designed to identify novel small molecules that induce selective degradation of drug target proteins through E3 ligase mediated proteasomal degradation. From molecular glues to monovalent degraders, Plexium is advancing a pipeline of novel targeted protein degraders for the treatment of cancer, neurodegeneration, and other diseases. Due to its expertise in TPD, Plexium has entered into strategic collaborations with Amgen and AbbVie to discover and develop a wide range of new therapies from cancer to neurological diseases. Supported by high quality investors, Plexium is well positioned to transform medicine.

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Plexium Investor and Media Contact:
Amy Conrad
Juniper Point