Solutions Ecosystems Reports Resources Data Pricing Login Book a demo
Power Law company profile

Plexxikon

Biotech & Life Sciences · Berkeley, United States · Founded 2000

Plexxikon was a biopharmaceutical company focused on the discovery and development of small molecule drugs to treat various human diseases. The company was founded in 2001 by Joseph Schlessinger, a professor of pharmacology at Yale University, and Sung-Hou Kim, a professor at the University of California, Berkeley. The firm operated with a distinct research and development model centered on its proprietary Scaffold-Based Drug Discovery™ platform. This platform utilized structural biology to guide the chemical design process, enabling the creation of targeted pharmaceuticals. The company's business model was centered on building a pipeline of pharmaceutical products and forming strategic partnerships for development and commercialization. A key collaboration was with Roche for the co-development and co-promotion of its lead drug candidate. Plexxikon's primary therapeutic focus areas included oncology, central nervous system disorders, and autoimmune diseases. One of its most notable achievements was the development of Zelboraf® (vemurafenib), a targeted therapy for melanoma patients with a specific gene mutation. This drug, co-developed with Roche, gained FDA approval in 2011. Another significant product developed by the company is Turalio (pexidartinib), for treating tenosynovial giant cell tumors. In a significant milestone, the Japanese pharmaceutical giant Daiichi Sankyo acquired Plexxikon in April 2011 for approximately $805 million, with an additional $130 million in potential milestone payments. Following the acquisition, Plexxikon continued to operate as an independent unit, retaining its name and facilities in Berkeley, California. However, in a strategic shift to focus on its antibody-drug conjugate (ADC) portfolio, Daiichi Sankyo announced the closure of the Plexxikon subsidiary, which took effect on March 31, 2022. The research pipeline and some employees transitioned, with some former assets and leadership forming a new company, Opna Bio, to continue the development of Plexxikon's research. Keywords: Plexxikon, biopharmaceutical, small molecule drugs, drug discovery, Scaffold-Based Drug Discovery, oncology, Zelboraf, vemurafenib, Turalio, pexidartinib, Daiichi Sankyo, Roche, Joseph Schlessinger, Sung-Hou Kim, melanoma treatment, tenosynovial giant cell tumor, targeted therapy, kinase inhibitors, structure-guided discovery, pharmaceutical development, Opna Bio

Valuation
$0–100M
Latest valuation · 2005
Unlock exact value
Headcount
<100
Current team size
Unlock exact value
Total funding Pre-IPO
$50–100M
Unlock exact value

Investors

8 investors on Plexxikon's cap table

Sourced from Dealroom's funding history. Investor profile links are shown where available.

Series A 8 investors entered at this stage
Plexxikon
Gimv
Pappas Capital
Alta Partners
CW Ventures
Walden International
Advanced Technology Ventures
NIF Ventures

Global footprint

Where Plexxikon has talent and traffic

Workforce by country
🇺🇸 United States · Berkeley HQ
Book a demo for the full country breakdown

Talent graph

The shape of Plexxikon's talent

Dealroom maps Plexxikon's team person by person — pinpointing the standout operators and scoring them across the six dimensions investors underwrite. The counts and shape below are a public preview; the named individuals and exact scores live in the platform.

7 team members profilednamed & role-tagged by Dealroom
14 employeestotal headcount
DimensionScore
AI Talent Score hidden — book a demo
Engineering Score hidden — book a demo
Product Score hidden — book a demo
Go-to-market Score hidden — book a demo
Leadership Score hidden — book a demo
Research Score hidden — book a demo
Book a demo to unlock Plexxikon's exact scores

Source: Dealroom Talent Intelligence. Public profiles show counts and the team's shape only — request a demo for the named individuals, per-person seniority and tenure, and team benchmarks vs peers.

Market sentiment

What the market is saying about Plexxikon

An AI-synthesized read of the highest-engagement posts about Plexxikon on X over the past 7 days. We rank by likes & retweets, ignore corporate channels, and surface the themes that broke out from real people.

Reading the room on X — pulling top posts and synthesizing themes…

Source: X recent search ranked by engagement (likes + retweets) · Synthesis by Claude · Cached for 1 hour

See Plexxikon on the full Dealroom platform

Live deal flow, founder pedigree, hiring signals, revenue trajectory, and the full cap table.