The Rise of Cyclic Peptides: Bridging the Gap in Modern Medicine

These "Goldilocks" molecules are not too large like monoclonal antibodies, which require injection, nor too small like traditional oral drugs, which often struggle with complex protein-protein interactions. 

For instance, Merck's research highlights the potential of macrocyclic peptides to cover extensive surface areas, making them highly effective in disrupting protein interactions crucial to various diseases. 

Protagonist Therapeutics' recent success with JNJ-2113, the first oral IL-23 receptor antagonist, underscores the therapeutic promise of cyclic peptides in treating conditions like moderate-to-severe plaque psoriasis.

The positive results from the Phase 2b FRONTIER 1 trial indicate not only efficacy but also tolerability, paving the way for further development in other immune-mediated inflammatory diseases. 

These advancements reflect the growing importance of cyclic peptides in expanding the therapeutic landscape, offering new avenues for oral treatments previously dominated by injectable biologics. As research and development in this field progresses, cyclic peptides are poised to significantly enhance the range and accessibility of treatments for complex diseases.

There are a number of drug discovery startups developing second generation cyclic peptides of second generation, including modified peptides and peptidomimetics. Below we summarized 5 such companies.