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Medical Excellence Capital

medexcelcap.com · New York, NY

“Discover disruptive life science technologies in gene therapy, cell therapy, synthetic biology, regenerative medicine, and AI/ML applied to drug discovery; deploy capital where MEC's network and expertise can accelerate value creation; develop world-class scientific and computational innovation.”

Leads & Follows
Lead Tendency
01Investment Thesis

Discover disruptive life science technologies in gene therapy, cell therapy, synthetic biology, regenerative medicine, and AI/ML applied to drug discovery; deploy capital where MEC's network and expertise can accelerate value creation; develop world-class scientific and computational innovation.

Exclusion Criteria

Does not appear to invest outside life sciences/precision health; no consumer, enterprise software, or non-healthcare deals observed in the portfolio.

02Investment Team
JP
John Prufeta
Founder, CEO & Managing Partner
EH
Eric Heil
Managing Partner
KK
Kim Kamdar
Managing Partner
BH
Brian Halak
Senior Advisor
JM
Joni Mancini
Managing Partner
MC
Max Colbert
Senior Associate
VL
Victoria Lewis
Research Associate
TM
Tess Marvin
Scientific Investment Strategist
OP
Olga Prufeta
MEC LP Liaison
JH
John Hornbostel
Counsel
AS
Annabel Stoddart
Chief of Staff
03F4 Research Brief

Medical Excellence Capital Research

Investment Thesis

Medical Excellence Capital (MEC) is an early-stage life sciences venture fund founded in 2020 by John Prufeta. MEC's stated thesis is a "Discover, Deploy, Develop" framework: discover disruptive life science technologies in gene therapy, cell therapy, synthetic biology, regenerative medicine, and AI/ML applied to drug discovery; deploy capital into high-potential companies where MEC's expertise and global network can accelerate value creation; and develop world-class innovation in medical scientific discovery, computational research applications, and transformational engineering. The firm describes itself as filling a "critical investment gap" in early-stage life science and health tech investing, positioned to discover, fund, and accelerate emerging deep-science precision health ventures. MEC's differentiator is a proprietary network of 1,100+ physician-scientists across 30+ academic medical centers, accessed through its affiliated global private health advisory firm, Medical Excellence Group (MedEx), founded by the same team in 2007.

Sector Focus

MEC's stated areas of focus are: AI to Advance Drug Discovery, Cell and Gene Therapy, Precision Medicine, Regenerative Medicine, and Synthetic Biology. The portfolio confirms this: iPSC-derived cell therapies (Aspen Neuroscience, GC Therapeutics), targeted protein degradation and RNA-binding protein drugs (Avilar Therapeutics, Trotana Therapeutics), metabolic disease small molecules (ClicBio), AI/ML-driven immuno-oncology and neuropsychiatric drug discovery (Immunitas Therapeutics, Synaptiq Therapeutics), diagnostics platforms (Pleno, Truvian), nonviral gene therapy delivery (SonoThera), ALS therapeutics (ProJenX), and novel peptide-based chemistry (Ladder Bio, TwoStep Therapeutics).

Stage Focus

MEC invests across company creation, seed, Series A, and Series B rounds. Portfolio stage-at-investment ranges from ground-up company creation (ProJenX, built with Project ALS) through Series C (Truvian), with the bulk concentrated in seed and Series A.

Check Size

MEC does not publish a specific check-size range. Round sizes MEC has participated in span from a $5.5M seed (Ladder Bio) to a $62.5M Series A (TwoStep Therapeutics, co-led with Insight Partners), suggesting a flexible ticket sized to round and ownership target rather than a fixed band.

Lead Tendency

MEC has both led and co-led rounds (Ladder Bio seed led solo; TwoStep Series A co-led with Insight Partners) and participated in larger syndicates as one of several investors (Immunitas Therapeutics' $97M raised from a syndicate including Alexandria Venture Investments, Novartis Venture Fund, Leaps by Bayer, and Longwood Fund). This points to a "both" lead/follow posture depending on deal size and syndicate composition.

Recent Activity

MEC's portfolio has been highly active through 2026: TwoStep Therapeutics closed an oversubscribed $62.5M Series A with FDA IND clearance (Sept 2026); Synaptiq Therapeutics launched via acquisition of Nobias Therapeutics' (MEC-majority-backed) SYN-001 asset (July 2026); GC Therapeutics appointed a new CSO (May 2026) and Board Chair (Jan 2026); Aspen Neuroscience reported positive 12-month ASPIRO trial data (March 2026); SonoThera presented new preclinical data and closed a $125M Series B (Jan–June 2026); and Ladder Bio (rebranded from ThirdLaw Molecular) raised a $5.5M seed led by MEC with MEC Managing Partner Eric Heil installed as CEO (Nov 2025).

Portfolio Highlights

Thirteen active portfolio companies span the full precision-health thesis, including Truvian (Series C point-of-care diagnostics), Aspen Neuroscience (Series B, Parkinson's cell therapy, Fast Track FDA designation), Immunitas Therapeutics (Series B, $97M raised, immuno-oncology), GC Therapeutics (Series A, iPSC programming platform, $75M raised), SonoThera ($125M Series B, nonviral genetic medicine), and TwoStep Therapeutics (Series A, $71.2M total raised, oncology peptide-drug conjugates).

Team

MEC's leadership team includes:

  • John Prufeta — Founder, CEO & Managing Partner; also Chairman of Medical Excellence Group and The Medical Excellence Foundation
  • Eric Heil, MBA — Managing Partner; ex-Domain Associates, cofounder/CEO of two prior venture-backed companies, now CEO of Ladder Bio
  • Kim Kamdar, PhD — Managing Partner; Domain Associates Partner since 2010, founding CEO roles at Truvian and Obalon, board experience across a dozen+ biotech exits
  • Brian Halak, PhD — Senior Advisor (formerly Managing Partner); Domain Associates Partner, co-founder of Tobira Therapeutics (acquired by Allergan) and WindMIL Therapeutics
  • Joni Mancini, CPA — Managing Partner, finance and operations
  • Max Colbert, MD, MBA — Senior Associate
  • Victoria Lewis, MD, MS — Research Associate
  • Tess Marvin, PhD — Scientific Investment Strategist, AI/ML and computational genomics background
  • Olga Prufeta — MEC LP Liaison, also Medical Excellence Group Vice Chairman
  • John Hornbostel, Esq. — Counsel
  • Annabel Stoddart — Chief of Staff

MEC also maintains a Scientific Advisory Board including Nobel laureate Gregg Semenza, MD, PhD (Johns Hopkins), Brad Ringeisen, PhD (Innovative Genomics Institute), Olga Troyanskaya, PhD (Princeton), Stephen Tsang, MD, PhD (Columbia), and Douglas Wallace, PhD (CHOP/UPenn).

Decision Process

MEC operates as a multi-partner team (Prufeta, Heil, Kamdar, Mancini as Managing Partners), consistent with a partnership-style decision process rather than a solo GP or formal investment committee structure.

Founder Preferences

MEC gravitates toward technical, often physician-scientist founders tackling large unmet medical needs with deep-science approaches (gene/cell therapy, synthetic biology, AI-driven drug discovery), frequently backing academic spinouts (CHOP, Stanford, Temple) and company-creation efforts alongside domain-expert operators.

Geographic Focus

The active portfolio is entirely US-based, concentrated in San Diego, the Boston/Cambridge biotech corridor, the Philadelphia area, the San Francisco Bay Area, and New York City — the classic US life-sciences hubs.

04Selected Portfolio
Biotech & Life Sciences
Aspen Neuroscience·Avilar Therapeutics·ClicBio·GC Therapeutics·Immunitas Therapeutics·Synaptiq Therapeutics·Pleno·ProJenX·SonoThera·Trotana Therapeutics·TwoStep Therapeutics·Ladder Bio
Healthcare & Digital Health
Truvian Health
Open the full portfolio→
05Recent Updates

Fresh signals from public announcements, essays, and portfolio activity.

See full activity (8) →
Co-led TwoStep Therapeutics' oversubscribed $62.5M Series A alongside Insight Partners, coinciding with FDA IND clearance for lead program TS-104.
INVESTMENT·twosteptx.com
SEP 9, 2026
Synaptiq Therapeutics launched via acquisition of SYN-001 from Nobias Therapeutics, an MEC-majority-backed company; Nobias retains an equity stake in Synaptiq.
MILESTONE·prnewswire.com
JUL 23, 2026
Portfolio company GC Therapeutics appointed Stefan Irion, MD, formerly of BlueRock Therapeutics, as Chief Scientific Officer.
MILESTONE·gc-tx.com
MAY 5, 2026
Portfolio company Aspen Neuroscience reported positive 12-month safety and efficacy data from its ASPIRO Phase 1/2a Parkinson's cell therapy trial.
MILESTONE·aspenneuroscience.com
MAR 18, 2026
Portfolio company SonoThera presented new preclinical data on its RIPPLE nonviral gene-therapy delivery platform for Duchenne Muscular Dystrophy at MDA 2026.
MILESTONE·sonothera.com
MAR 5, 2026
06Frequent co-investors
LB
Leaps by Bayer
Both backed 2 of the same companies
SonoThera, Immunitas Therapeutics
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Quick Reference
Stages
Seed · Series A · Series B
Decision
Partnership
Involvement
Board Seat
Location
New York, NY
Sector Focus
Biotech & Life SciencesHealthcare & Digital Health
Technology
AI/ML Drug DiscoveryCell And Gene TherapyPrecision MedicineRegenerative MedicineSynthetic Biology
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F4 Intelligence Report · Last Researched September 12, 2026F4 Research Engine