Plexium
San Diego, US · Founded 2018 · 33 employees on LinkedIn · 8 known investors
Find your way into Plexium
Plexium is a targeted protein degradation company developing small molecule therapeutics for treating diseases with high unmet medical needs using their proprietary DELTA Discovery platform.
Founders & leadership
MM
Michael Martin, Ph.D.Chief Executive Officer, President
JF

Jorge F. DiMartinoinJorge F. DiMartino is a physician scientist with over 18 years of experience in oncology drug development, including strategic involvement in the early development of marketed cancer therapeutics such as vismodegib, venetoclax, and enasidenib. He is founder of Plexium, which develops targeted protein degradation therapies.
MM

SM

Stephen MullennixinChief Financial OfficerHe previously served as Chief Financial Officer and Chief Operating Officer at public and private companies in life sciences, biotechnology, and infrastructure, with experience leading public financings, M&A, and international teams.
Board
Investors · 8
CRV (Charles River Ventures)Bay Area · $250K – $5M
DCVC (Data Collective)Palo Alto · $5M – $25M
M VenturesLos Angeles · $10.8M
Neotribe VenturesMenlo Park · $250K – $2M
SoftBank Vision FundLondon
TCG CrossoverPalo Alto
The Column GroupSan Francisco · $30M
Pivotal Life SciencesreportedSan Franciscovia Rob Hopfner · board
Reported raises · per SEC filings
Form D private placements$60.1M disclosed across 1 round · 2025
▶$60.1MraisedAug 2025 · 20 investors · BiotechnologyRule 506(b)
▶$60.1MraisedAug 2025 · 20 investors · Biotechnology
Rule 506(b)Officers, directors & promoters on the filing
- Serge MesserlianDirector
- Cariad ChesterDirector
- Patrick RiversDirector
- Leon ChenDirector
- Rob HopfnerDirector
- Michael MartinExecutive Officer, Director
- Michael GreyDirector
- Stephen MullennixExecutive Officer
- Gorjan HrustanovicDirector
- Offering amount
- $60.1M
- Amount sold
- $60.1M
- First sale
- Jul 2025
- Incorporated
- Corporation, Delaware
- Federal exemptions
- 06b
Source: SEC EDGAR Form D. Amounts as filed; amended filings shown once at their latest values.
Founder mafia
2 people who came through Plexium went on to found or lead other companies.
Competitors · 1
by search overlapCompanies competing with Plexium for the same Google search keywords, organic and paid, via search-intersection analysis.
Frequently asked questions
- What does Plexium do?
- Plexium is a targeted protein degradation company developing small molecule therapeutics for treating diseases with high unmet medical needs using their proprietary DELTA Discovery platform.
- Who are Plexium's investors?
- Plexium's investors include CRV (Charles River Ventures), DCVC (Data Collective), M Ventures, Neotribe Ventures, SoftBank Vision Fund, TCG Crossover, The Column Group, Pivotal Life Sciences.
- How much funding has Plexium raised?
- Plexium has disclosed $60.1M raised across 1 round.
- Where is Plexium headquartered?
- Plexium is headquartered in San Diego, US.










