Lewis J. Geffen

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  • Harvard Law School (JD)
  • University of Massachusetts - Amherst (BA)

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  • Massachusetts
  • New York

Lewis is co-chair of the firm’s Life Science and Venture Capital & Emerging Companies Practice Groups.  He has over 25 years of experience representing biotechnology, pharmaceutical, medical device and medtech companies in all aspects of their business and legal affairs.  Lewis serves as principal outside or general counsel to leading life science companies, advising management and directors as these companies raise capital, in-license and acquire technology and assets, and then collaborate or partner with others.  In addition to day-to-day corporate counseling and strategic advice to his clients, Lewis regularly advises on a variety of major domestic and international business transactions, including venture capital and other private financings, technology licensing, mergers and acquisitions, strategic alliances, and public offerings.

His recent client representations include work with:

Venture Financings

  • Aura Biosciences in its $30M financing to advance the clinical development of its Ocular Melanoma treatment
  • Spero Therapeutics in its $51.7M financing to advance its pipeline of antibacterials focused on drug-resistant bacterial infections
  • Synlogic in its $42M, $40M, $30M and $42M financings to develop “living therapeutics”
  • Ysios Capital and Sofinnova Ventures in the $30M Series B financing of BioClin Therapeutics, Inc.
  • Macrolide Pharmaceuticals in its $22M Series A financing to develop novel antibiotics
  • Opsonix in its $8M Series A financing to develop a broad spectrum pathogen-extracting therapy
  • Venture investors in the $21 Series B financing of Aura Biosciences, to treat ocular melanoma 
  • RA Capital in numerous venture financings, including Arvinas, Cidara Therapeutics, G1 Therapeutics and White Swell Medical
  • MVM Life Science Partners in numerous venture financings, including AccuVein, BioTheranostics, Zipline Medical, Cheetah Medical and Solx
  • Merck Research and Licensing (MRL) Ventures in several financings, including RaNA Therapeutics and miRagen Therapeutics

Strategic Alliances, M&A and Public Offerings

  • Spero Therapeutics in its $88M Initial Public Offering
  • Synlogic in its IPO by way of a reverse merger with Mirna Therapeutics, Inc.
  • Synlogic in its $50M follow on public offering
  • Synlogic in its global R&D collaboration with AbbVie to develop novel synthetic medicines to treat inflammatory bowel disease
  • Biogen Idec in its collaboration with Ataxion to develop drugs to treat hereditary ataxias
  • Macrolide Pharmaceuticals in its agreement with Cempra to develop a synthetic manufacturing  process for solithromycin
  • Amorsa Therapeutics in its research, option and license agreement with Janssen Pharmaceuticals, to develop novel ketamine-derived drugs for treatment-resistant depression
  • Spero Therapeutics in its acquisition of worldwide rights to VXc-486/VXc-100 and a portfolio of innovative antibacterial compounds from Vertex Pharmaceuticals
  • Solid Biosciences in numerous its collaborations and licenses, including its development partnership with Debiopharm
  • Spero Therapeutics in its acquisition of next generation antibacterial candidates from Pro Bono Bio Ltd
  • AFT Pharmaceuticals in its $33M Initial Public Offering
  • CareWell Urgent Care in its joint venture with UMass Memorial Health Care to develop urgent care centers in Central MA
  • Paratek Pharmaceuticals in its $485M global collaboration with Novartis
  • Beacon Endoscopic in its sale to Covidien



Recognitions & Awards

  • Recognized by The Legal 500 United States as “a well-known life sciences expert” for Venture Capital and Emerging Companies (2014)
  • Recommended by The Legal 500 United States for Venture Capital and Emerging Companies (2013 – 2017)
  • Martindale-Hubbell AV Preeminent

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