2017 • Startup

Spero Therapeutics

Through a series of acquisitions and other deals, SPERO THERAPEUTICS is building an armamentarium of weapons to kill drug-resistant bacteria. One, for instance, doesn’t destroy bacteria on its own, but instead disrupts the outer membrane of tough-to-drug Gram-negative bacteria so that they’re susceptible to antibiotics. Spero just raised $51.7 million this year, and $110 million in total since its 2014 inception. After that last raise, CEO Ankit Mahadevia mentioned Spero might seek an IPO in the future.

Ankit Mahadevia, Spero Therapeutics • Photography by Alex Gagne and Rythum Vinoben