Genome & Co. posts survival data from phase 2 microbiome cancer trial, plans more studies

Genome & Co. has shared data from a midphase trial testing its bacterial strain in combination with a checkpoint inhibitor. The readout encouraged the biotech to plan further clinical studies to validate the combination as a third-line treatment.

The idea of modulating the microbiome to improve the effects of checkpoint inhibition was in fashion a few years back. Bristol Myers Squibb teamed up with Enterome, Johns Hopkins University and Vedanta Biosciences in quick succession in 2017 and 2018, only for clinical setbacks to dent enthusiasm in 2021. That year, Seres Therapeutics and Vedanta were respectively hit by slow enrollment and lackluster data.

Yet, while interest in the concept has waned at times, it has never gone away. Microbiotica struck a deal to test its live biotherapeutic product in combination with Merck & Co.’s Keytruda last year, and Genome & Co. has pushed ahead with a phase 2 trial of its candidate, GEN-001. 

The Korean biotech posted “positive” interim results of the study last year without sharing data to back up its enthusiasm. That changed at the American Society of Clinical Oncology (ASCO) Gastrointestinal Cancers Symposium, where Genome & Co. shared response and survival data in gastric cancer patients who received its single-strain bacteria in combination with the checkpoint inhibitor Bavencio.

In the ASCO abstract, Genome & Co. said five of the 42 patients had confirmed partial responses. There was also one unconfirmed partial response. Genome & Co.’s accompanying press release said seven of the 42 patients had partial responses. 

Three of the partial responses happened in the eight PD-L1-positive participants who had previously not responded to immunotherapy. Jeeyun Lee, M.D., a professor and co-author of the abstract, called the response rate in immunotherapy refractory subpopulation “particularly promising.” Median progression-free and overall survival were 1.7 months and 7.9 months, respectively.

The ASCO abstract went public last week but Genome & Co. only sent an English-language press release about the news Wednesday.