Ultimate Longevity Bible

Company

Sirtris Pharmaceuticals (Historic)

Last updated 2026-05-30· 1 min read

Reviewed by the Ultimate Longevity Bible editorial team. Educational reference — not medical advice. See disclaimer.

What it was

Sirtris Pharmaceuticals was founded in 2004 by David Sinclair and Christoph Westphal to develop sirtuin-activating compounds (STACs) based on the then-prevailing hypothesis that resveratrol activated SIRT1 and could deliver caloric-restriction-like benefits.

Acquired by GlaxoSmithKline in 2008 for $720M — one of the larger early-stage biotech acquisitions in the field’s history.

What happened

  • Subsequent biophysical work showed the original SIRT1 activation assay was an artifact of the fluorophore-labelled substrate used.
  • Clinical-stage programmes (SRT2104, others) failed to demonstrate meaningful disease benefit.
  • GSK closed Sirtris in 2013, spinning some assets back out.

What we learned

  • Hype-cycle effects in biotech: a high-profile mechanism can attract massive funding before the mechanism is well-validated.
  • Biophysical assay artifacts can sustain wrong mechanistic stories for years.
  • The "sirtuin theory of aging" required substantial refinement; AMPK activation may be a more honest description of what some "STACs" actually do.

Related entries

David Sinclair, Sirtuins, Resveratrol, resTORbio (historic).

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