Rarebird makes Px coffee.


Total Raised
$3.4 million
Latest Round


AgFunder, First Round Capital.


Rarebird is creating jitter-free coffee using Paraxanthine (Px) instead of caffeine. Paraxanthine offers the benefits of caffeine—like increased alertness and productivity—without causing anxiety or jitters. Px is less toxic and has a shorter half-life than caffeine. With 70% of Americans drinking coffee and a third sensitive to caffeine, Rarebird targets a substantial market.

Why we invested

  • An original wedge into a high margin $450b market
  • Sexy market: coffee isn't a vitamin, it's a narcotic. 
  • N-of-1 type company
  • Strong patent of Px use in coffee.
  • Great founding team.



Contact Rarebird

[email protected]




Jeffrey Dietrich

Before founding Rarebird, Jeffrey co-founded Lygos, a biotech startup targeting the petroleum-derived chemicals industry with bio-based alternatives. He served as Lygos’ CTO for nearly nine years (2011 - 2019), during which time the startup raised $44M. His role involved producing metric tons of biochemicals, serving as the principal investigator on $10M in federal contracts, and being the lead inventor on 17 patents. Jeffrey has a BS in Bioengineering from Rice University and a PhD in Bioengineering from Berkeley. Jeffrey


Before co-founding Rarebird, AD worked at RBI in various capacities, including lead, development, real estate, architecture, and design for Popeyes America. She was also an Area Franchise Lead with Burger King’s West Division and a Category Manager for Beef, Desserts, and Sides at Burger King North America and was instrumental in bringing the Impossible Whopper to Burger King.