Longwood Fund

Managing Partners Christoph Westphal, Rich Aldrich, and Michelle Dipp form the core investment committee. Each brought an exit track record prior to Longwood — Westphal and Aldrich from Sirtris Pharmaceuticals (sold to GSK in 2008), Dipp from Alnara Pharmaceuticals — and they collectively approve every new company creation. Partner David Steinberg handles operational aspects of portfolio company formation.

The firm does not source deals in the traditional sense — it invents them. Longwood identifies translational science from Harvard, MIT, and the Dana-Farber ecosystem, then builds a company around the intellectual property with a CEO from its own network. The academic founder typically retains a significant scientific stake while Longwood handles the capital and corporate infrastructure.

It operates as a hybrid. The firm raises limited-partner vehicles like a standard venture fund but deploys the capital through a venture-creation model — originating companies, installing management, and funding the initial preclinical program before introducing institutional co-investors at Series A or B. LPs are passive investors in the fund vehicle, not in individual portfolio companies.

Seed and Series A in therapeutically-focused biotech, often before a formal asset has been nominated. The model relies on creating companies at the point of IP licensing, funding the initial preclinical proof-of-concept work, and retaining a board seat through subsequent financing rounds. The firm does not typically lead crossover rounds or public-equity placements.

Longwood Fund and Longwood Healthcare Leaders are distinct entities. The fund is the venture-creation vehicle managed by Westphal, Aldrich, and Dipp. Longwood Healthcare Leaders operates as an invitation-only conference series for biopharma CEOs and institutional investors, sharing certain principals but not co-mingling capital.

The firm concentrates on prescription therapeutics — oncology, neurology, metabolic disorders, and genetic medicine account for the bulk of its portfolio. It systematically avoids medical devices, digital-health platforms, and diagnostics, preferring modalities where a well-defined clinical trial endpoint can unlock an acquisition or large Series B within three to four years of formation.

Prior to Fund I, the managing partners were responsible for Sirtris Pharmaceuticals (acq. GlaxoSmithKline, 2008) and Alnara Pharmaceuticals (acq. Eli Lilly, 2010). Since formalizing in 2010, Longwood has seeded companies including Avidity Biosciences (NASDAQ IPO 2020), Pyxis Oncology (NASDAQ IPO 2021), and Nimbus Therapeutics, whose TYK2 inhibitor program was licensed to Takeda in a multi-billion-dollar deal (per the firm's official communications).